UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, DC 20549

FORM 10-Q

(Mark One)

For the quarterly period ended March 31, 2021

OR

For the transition period from_______________ to _______________

Commission File Number: 001-39103

CABALETTA BIO, INC.

(Exact Name of Registrant as Specified in its Charter)

Registrant’s telephone number, including area code: (267) 759-3100

Securities registered pursuant to Section 12(b) of the Act:

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.     Yes ☒    No  ☐

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files).     Yes  ☒    No  ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).     Yes  ☐    No  ☒

As of April 29, 2021, the registrant had 24,928,333 shares of common stock, $0.00001 par value per share, outstanding.

Table of Contents

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Summary of the Material and Other Risks Associated with Our Business

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SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS

This Quarterly Report on Form 10-Q, including the sections entitled “Risk Factors” and “Management’s Discussion and Analysis of Financial Condition and Results of Operations,” contains express or implied forward-looking statements that are based on our management’s belief and assumptions and on information currently available to our management. Although we believe that the expectations reflected in these forward-looking statements are reasonable, these statements relate to future events or our future operational or financial performance, and involve known and unknown risks, uncertainties and other factors, including, without limitation, risks, uncertainties and assumptions regarding the impact of the COVID-19 pandemic on our business, operations, strategy, goals and anticipated timelines, our ongoing and planned preclinical activities, our ability to initiate, enroll, conduct or complete ongoing and planned clinical trials, our timelines for regulatory submissions and our financial position that may cause our actual results, performance or achievements to be materially different from any future results, performance or achievements expressed or implied by these forward-looking statements. Forward-looking statements in this Quarterly Report on Form 10-Q include, but are not limited to, statements about:

These factors should not be construed as exhaustive and should be read in conjunction with the other cautionary statements that are included in this Quarterly Report on Form 10-Q. The forward-looking statements contained in this Quarterly Report on Form 10-Q are made as of the date of this Quarterly Report on Form 10-Q, and we undertake no obligations to publicly update or review any forward-looking statement, whether as a result of new information, future developments or otherwise.

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PART I—FINANCIAL INFORMATION

Item 1. Financial Statements.

CABALETTA BIO, INC.

Condensed Balance Sheets

(in thousands, except share and per share amounts)

The accompanying notes are an integral part of these financial statements.

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CABALETTA BIO, INC.

Condensed Statements of Operations and Comprehensive Loss

(in thousands, except share and per share amounts)

(unaudited)

The accompanying notes are an integral part of these financial statements.

4

CABALETTA BIO, INC.

Condensed Statements of Stockholders’ Equity

(in thousands, except share amounts)

(unaudited)

The accompanying notes are an integral part of these financial statements.

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CABALETTA BIO, INC.

Condensed Statements of Cash Flows

(in thousands)

(unaudited)

The accompanying notes are an integral part of these financial statements.

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CABALETTA BIO, INC.

Notes to Unaudited Condensed Financial Statements

(in thousands, except share and per share amounts)

1. Basis of Presentation

Cabaletta Bio, Inc. (the Company or Cabaletta) was incorporated in April 2017 in the State of Delaware as Tycho Therapeutics, Inc. and, in August 2018, changed its name to Cabaletta Bio, Inc. The Company is headquartered in Philadelphia, Pennsylvania. Cabaletta is a clinical-stage biotechnology company focused on the discovery and development of engineered T cell therapies for B cell-mediated autoimmune diseases.

Principal operations commenced in April 2018, when the Company executed sponsored research agreements with the Trustees of the University of Pennsylvania (Penn).

On October 29, 2019, the Company completed its initial public offering (IPO) of 6,800,000 shares of common stock at an offering price of $11.00 per share. The Company received net proceeds of $66,156 after deducting underwriting discounts, commissions and estimated offering expenses. In connection with the IPO, the Company’s outstanding shares of Convertible Preferred Stock were automatically converted into 12,904,534 shares of common stock. In November 2019, the underwriters partially exercised their option and purchased an additional 475,501 shares of common stock resulting in net proceeds to the Company of approximately $4,864, after deducting underwriting discounts and commissions.

Risks and Uncertainties

The Company does not expect to generate revenue from sales of engineered T cell therapies for B cell-mediated autoimmune diseases or any other revenue unless and until the Company completes preclinical and clinical development and obtains regulatory approval for one or more product candidates. If the Company seeks to obtain regulatory approval for any of its product candidates, the Company expects to incur significant commercialization expenses.

The Company is subject to risks common to companies in the biotechnology industry including, but not limited to, new technological innovations, protection of proprietary technology, dependence on key personnel, compliance with government regulations and the need to obtain additional financing. As a result, the Company is unable to predict the timing or amount of increased expenses or when or if the Company will be able to achieve or maintain profitability. Further, the Company is currently dependent on the University of Pennsylvania (Penn) for much of its preclinical research, clinical research and development activities and initial manufacturing activities (Note 5). Product candidates currently under development will require significant additional research and development efforts, including extensive preclinical and clinical testing and regulatory approval, prior to commercialization. Even if the Company is able to generate revenues from the sale of its product candidates, if approved, it may not become profitable. If the Company fails to become profitable or is unable to sustain profitability on a continuing basis, then it may be unable to continue its operations at planned levels and be forced to reduce its operations.

In December 2019, a novel strain of coronavirus (COVID-19) surfaced in Wuhan, China and has since reached multiple other regions and countries. The COVID-19 pandemic is evolving and to date has led to the implementation of various responses, including government-imposed quarantines, travel restrictions and other public health safety measures, which have delayed the commencement of non-COVID-19-related clinical trials, among other restrictions. The extent to which COVID-19 impacts the Company’s operations or those of its third party partners will depend on future developments, which are highly uncertain and cannot be predicted with confidence, including new information that may emerge concerning the severity of COVID-19, the impact of new strains of the virus, the effectiveness and availability of vaccines and the actions to contain COVID-19 or treat its impact, among others. The Company’s financial results to date have not been significantly impacted by COVID-19, however, the Company cannot at this time predict the specific extent, duration, or full impact that the COVID-19 pandemic will have on its financial condition, operations, and business plans, including its ability to raise additional capital, the timing and enrollment of patients in its ongoing and planned clinical trials, future financings and other expected milestones of its product candidates.

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Liquidity

The Company has sustained annual operating losses since inception and expects to continue to generate operating losses for the foreseeable future. The Company’s ultimate success depends on the outcome of its research and development activities. The Company had cash and cash equivalents and investments of $102,028 as of March 31, 2021. Through March 31, 2021, the Company has incurred an accumulated deficit of $76,000. Management expects to incur additional losses in the future as it continues its research and development and will need to raise additional capital to fully implement its business plan and to fund its operations.

The Company intends to raise such additional capital through a combination of equity offerings, debt financings, government funding arrangements, strategic alliances or other sources. However, if such financing is not available at adequate levels and on a timely basis, or such agreements are not available on favorable terms, or at all, as and when needed, the Company will need to reevaluate its operating plan and may be required to delay or discontinue the development of one or more of its product candidates or operational initiatives. The Company expects that its cash and cash equivalents as of March 31, 2021, will be sufficient to fund its projected operations for at least 12 months following the date the Company files this Quarterly Report on Form 10-Q with the Securities and Exchange Commission (SEC).

2. Summary of Significant Accounting Policies

Unaudited Interim Financial Information

The accompanying unaudited interim financial statements have been prepared in conformity with generally accepted accounting principles (GAAP) and the applicable rules and regulations of the SEC regarding interim financial reporting. Any reference in these notes to applicable guidance is meant to refer to GAAP as found in the Accounting Standards Codification and Accounting Standards Updates (ASU) of the Financial Accounting Standards Board (FASB). As permitted under these rules, certain footnotes and other financial information that are normally required by GAAP have been condensed or omitted.

In the opinion of management, the accompanying unaudited interim financial statements include all normal and recurring adjustments (which consist primarily of accruals and estimates that impact the financial statements) considered necessary to present fairly the Company’s financial position as of March 31, 2021 and the results of its operations and its cash flows for the three months ended March 31, 2021 and 2020. The results for the three months ended March 31, 2021 are not necessarily indicative of results to be expected for the year ending December 31, 2021, any other interim periods, or any future year or period. The balance sheet as of December 31, 2020 included herein was derived from the audited financial statements as of that date. The unaudited interim financial statements, presented herein, do not contain the required disclosures under GAAP for annual financial statements. These unaudited financial statements should be read in conjunction with the Company’s audited financial statements, which are included in the Company’s 2020 Annual Report on Form 10-K, filed with the SEC on March 16, 2021 (2020 Annual Report).

Use of Estimates

The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities as of the date of the financial statements and the reported amounts of expenses during the reporting period. Significant estimates and assumptions made in the accompanying financial statements include, but are not limited to, the fair value of stock-based compensation, the valuation allowance on the Company’s deferred tax assets and certain accruals. The Company evaluates its estimates and assumptions on an ongoing basis using historical experience and other factors and adjusts those estimates and assumptions when facts and circumstances dictate. Actual results could differ from those estimates.

Off-Balance Sheet Risk and Concentrations of Credit Risk

Financial instruments, which potentially subject the Company to significant concentrations of credit risk, consist primarily of cash and cash equivalents, which are primarily invested in U.S. treasury-based money market funds, and available-for-sale debt securities, which are invested in investment grade corporate bonds with high credit quality issuers. These investments have maturities in 2021. A portion of the Company’s cash is maintained at a federally insured financial institution. The deposits held at this institution are in excess of federally insured limits. The Company has not experienced any losses in such accounts and management believes that the Company is not exposed to significant credit risk due to the financial position of the depository institution in which those deposits are held. The cash in this account is swept daily into U.S. treasury-based and U.S. government-based money market funds. The Company has no off‑balance sheet risk, such as foreign exchange contracts, option contracts, or other foreign hedging arrangements.

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Significant Accounting Policies

There have been no significant changes to the Company’s accounting policies during the three months ended March 31, 2021, as compared to the significant accounting policies described in Note 2 of the “Notes to the Financial Statements” in the Company’s audited financial statements included in its 2020 Annual Report.

Fair Value Measurement

Assets and liabilities recorded at fair value on a recurring basis in the balance sheets are categorized based upon the level of judgment associated with the inputs used to measure their fair values. Fair value is defined as the exchange price that would be received for an asset or an exit price that would be paid to transfer a liability in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. The authoritative guidance on fair value measurements establishes a three-tier fair value hierarchy for disclosure of fair value measurements as follows:

Level 1—Observable inputs such as unadjusted, quoted prices in active markets for identical assets or liabilities at the measurement date.

Level 2—Inputs (other than quoted prices included in Level 1) that are either directly or indirectly observable for the asset or liability. These include quoted prices for similar assets or liabilities in active markets and quoted prices for identical or similar assets or liabilities in markets that are not active.

Level 3—Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities.

Emerging Growth Company Status

The Company is an emerging growth company, as defined in the Jumpstart Our Business Startups Act of 2012 (the JOBS Act). Under the JOBS Act, emerging growth companies can delay adopting new or revised accounting standards issued subsequent to the enactment of the JOBS Act, until such time as those standards apply to private companies. The Company has elected to use this extended transition period for complying with new or revised accounting standards that have different effective dates for public and private companies until the earlier of the date that it (i) is no longer an emerging growth company or (ii) affirmatively and irrevocably opts out of the extended transition period provided in the JOBS Act. As a result, these financial statements may not be comparable to companies that comply with the new or revised accounting pronouncements as of public company effective dates.

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Recently Issued Accounting Pronouncements

In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842), with guidance regarding the accounting for and disclosure of leases. The update requires lessees to recognize the liabilities related all leases, including operating leases, with a term greater than 12 months on the balance sheet. This update also requires lessees and lessors to disclose key information about their leasing transactions. This guidance is effective for public companies for annual and interim periods beginning after December 15, 2018. In June 2020, the FASB issued ASU 2020-05, Revenue from Contracts with Customers (Topic 606) and Leases (Topic 842), which granted a one-year effective date delay for certain companies to fiscal years beginning after December 15, 2021, and interim periods within fiscal years beginning after December 15, 2022. Early adoption is permitted. As an Emerging Growth Company, the Company expects to adopt Topic 842 in 2022 and has not yet finalized the assessment of the impact that Topic 842 will have on its financial statements or financial statement disclosures.

3. Fair Value Measurements

Fair value of financial instruments

At March 31, 2021 and December 31, 2020, the Company’s financial instruments included cash and cash equivalents, accounts payable and accrued expenses. The carrying amounts reported in the Company's financial statements for these instruments approximate their respective fair values because of the short-term nature of these instruments.

The following tables present financial information about the Company’s financial assets measured at fair value on a recurring basis and indicate the level of the fair value hierarchy utilized to determine such fair values:

Money market funds are measured at fair value on a recurring basis using quoted prices and are classified as Level 1 inputs. Investments are measured at fair value based on inputs other than quoted prices that are derived from observable market data and are classified as Level 2 inputs. There were no transfers of assets between the fair value measurement levels during the three months ended March 31, 2021 or 2020.

For debt securities classified as available-for-sale investments, the Company records unrealized gains or losses resulting from changes in fair value between measurement dates as a component of other comprehensive income.

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4. Accrued and Other Current Liabilities

Accrued and other current liabilities consist of the following:

5. Collaborations, Licensing Agreements and Other Agreements

Research Service Agreement

In February 2021, the Company entered into a research service agreement with the Children’s Hospital of Philadelphia (CHOP) for vector manufacturing. Research and development expense related to this research service agreement with CHOP recognized in the accompanying statements of operations was $222 and $0 for the three months ended March 31, 2021 and 2020, respectively. There was $222 due under this agreement as of March 31, 2021. This agreement has a remaining cost of $448, expected to be incurred in 2021.

Amended and Restated License Agreement with the Trustees of the University of Pennsylvania and Children’s Hospital of Philadelphia

In August 2018, the Company entered into a license agreement with Penn, as amended and restated in July 2019 to include CHOP as a party, and as amended in May 2020 (the License Agreement) pursuant to which the Company obtained (a) a non-exclusive, non-sublicensable worldwide license to certain of Penn’s intellectual property to conduct research, product development, clinical trials, cell manufacturing and other activities, and (b) an exclusive, worldwide, royalty-bearing right and license, with a right to sublicense, on a target-by-target basis, under certain of Penn’s intellectual property to make, use, sell, offer for sale, import, and otherwise commercialize products for the treatment of autoimmune and alloimmune diseases.

Unless earlier terminated, the License Agreement expires on the expiration or abandonment or other termination of the last valid claim in Penn’s intellectual property licensed by the Company. The Company may terminate the License Agreement at any time

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for convenience upon 60 days written notice. In the event of an uncured, material breach, Penn may terminate the License Agreement upon 60 days written notice.

Under the terms of the License Agreement, the Company was obligated to pay $2,000 annually for three years beginning August 2018 for funding to the laboratories of each of Drs. Milone and Payne (see Sponsored Research Agreements). During the term of the License Agreement until the first commercial sale of the first product, the Company is obligated to pay Penn a non-refundable, non-creditable annual license maintenance fee of $10.

The Company is required to pay certain milestone payments upon the achievement of specified clinical and commercial milestones. Milestone payments are reduced by a certain percentage for the second product that achieves a milestone, by an additional percentage for the third product that achieves a milestone, and so on, for each subsequent product that achieves a milestone. In the event that the Company is able to successfully develop and launch multiple products under the License Agreement, total milestone payments could be approximately $21,000. Penn is also eligible to receive tiered royalties at percentage rates in the low single-digits, subject to an annual minimum royalty, on annual worldwide net sales of any products that are commercialized by the Company or its sublicensees that contain or incorporate, or are covered by, the intellectual property licensed by the Company. To the extent the Company sublicenses its license rights under the License Agreement, Penn would be eligible to receive tiered sublicense income at percentage rates in the mid-single to low double-digits. There were no amounts due under the License Agreement as of March 31, 2021. 

Sponsored Research Agreements

The Company has sponsored research agreements with two faculty members at Penn, who are also scientific co-founders of the Company and members of the Company’s scientific advisory board. In May 2020, one of the agreements was amended to expand the scope of sponsored research. In August 2020, this agreement was further amended to extend the term of the original research plan. In April 2021, the other sponsored research agreement was amended to extend the term of the original research plan.

Under the amended agreements, the Company has committed to funding a defined research plan through February 2023. The total estimated cost of $11,781 under the agreements satisfies the Company’s annual obligation under the License Agreement (see Amended and Restated License Agreement with the Trustees of the University of Pennsylvania above). As of March 31, 2021, $7,927 of cost has been incurred pursuant to these agreements. Research and development expense related to these research agreements recognized in the accompanying statements of operations was $837 and $603 for the three months ended March 31, 2021 and 2020, respectively. Advance payments under these research agreements included in prepaid expenses and other current assets in the accompanying balance sheets were $1,379 and $1,851 as of March 31, 2021 and December 31, 2020, respectively. There was $0 and $217 included in Accrued and other current liabilities in the accompanying balance sheets as of March 31, 2021 and December 31, 2020, respectively.

Master Translational Research Services Agreement

In October 2018, the Company entered into a services agreement (the Services Agreement) with Penn for additional research and development services from various laboratories within Penn. The research and development activities are detailed in separately executed Penn organization-specific addenda. In May 2020, the Company amended its Addendum with the Center for Advanced Retinal and Ocular Therapeutics (CAROT) to expand access to vector manufacturing.

Research and development expense related to executed addenda under the master translational research service agreement with Penn recognized in the accompanying statements of operations for the three months ended March 31, 2021 and 2020 was $395 and $711, respectively. The Company may incur additional expenses up to $1,360 through the remaining term of the CAROT Amended Addendum.

Subscription and Technology Transfer Agreement

In July 2019, the Company entered into a subscription and technology transfer agreement pursuant to which the Company owed Penn an upfront subscription fee, which was paid in the third quarter of 2019, and a nominal non-refundable royalty on the net sales of products, a portion of which will be credited toward milestone payments and royalties, respectively, under the Amended License Agreement. Technology transfer activities will be at the Company’s cost and subject to agreement as to the technology to be transferred. Expense recognized under this agreement was $150 and $0 during the three months ended March 31, 2021 and March 31, 2020, respectively.

Collaboration and License Agreement

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In July 2020, the Company entered into a collaboration and license agreement with Artisan Bio, Inc. (Artisan), wherein the Company and Artisan agreed to collaborate to potentially enhance certain pipeline products of the Company at specific targets using Artisan’s gene editing and engineering technology. If the Artisan technology is applied to any of the Company’s products, the Company will be responsible for the development, manufacturing, and commercialization of any such products. Under the terms of the agreement, the Company was required to pay Artisan a nominal upfront fee, as well as costs associated with research and development activities. Artisan is eligible to receive future research, development and regulatory milestones, and is also eligible to receive sales milestones and tiered royalties on net sales of products that incorporate the Artisan technology. The Company can terminate the agreement at will upon advance written notice with payment of a nominal cancellation fee.

Manufacturing Agreement

In January 2021, the Company entered into a Development and Manufacturing Services Agreement (WuXi Agreement) with WuXi Advanced Therapies, Inc. (WuXi) to serve as the Company’s cell processing manufacturing partner for the anticipated MuSK-CAART Phase 1 clinical trial. The Company has the right to terminate the WuXi Agreement for convenience or other reasons specified in the WuXi Agreement upon prior written notice. If the Company terminates the WuXi Agreement, it will be obligated to pay an early termination fee of $1,500.

6. Commitments and Contingencies

Operating Lease Agreement

In February 2019, the Company entered into an operating lease agreement for new office space in Philadelphia, Pennsylvania. The lease term commenced in May 2019 and will expire in July 2022. The initial annual base rent is $261, and such amount will increase by 2% annually on each anniversary of the commencement date. The Company records rent expense on a straight-line basis over the lease term. Rent expense related to this lease agreement recognized in the accompanying statements of operations was $68 and $67 for the three months ended March 31, 2021 and 2020, respectively.

As of March 31, 2021, the future minimum payments for operating leases are as follows:

Other Purchase Commitments

In the normal course of business, the Company enters into various purchase commitments with third-party contract manufacturers for the manufacture and processing of its product candidates and related raw materials, contracts with contract research organizations for clinical trials and agreements with vendors for other services and products for operating purposes. These agreements generally provide for termination or cancellation, other than for costs already incurred.  

Indemnification

The Company enters into certain types of contracts that contingently require the Company to indemnify various parties against claims from third parties. These contracts primarily relate to (i) the Company’s Amended and Restated Bylaws (bylaws) under which the Company must indemnify directors and executive officers, and may indemnify other officers and employees, for liabilities arising out of their relationship, (ii) contracts under which the Company must indemnify directors and certain officers and consultants for liabilities arising out of their relationship, (iii) contracts under which the Company may be required to indemnify partners against certain claims, including claims from third parties asserting, among other things, infringement of their intellectual property rights, and (iv) procurement, consulting, or license agreements under which the Company may be required to indemnify vendors, consultants or licensors for certain claims, including claims that may be brought against them arising from the Company’s acts or omissions with respect to the supplied products, technology or services. From time to time, the Company may receive indemnification claims under these contracts in the normal course of business. In addition, under these contracts, the Company may have to modify the accused infringing intellectual property and/or refund amounts received.

In the event that one or more of these matters were to result in a claim against the Company, an adverse outcome, including a judgment or settlement, may have a material adverse effect on the Company’s future business, operating results or financial condition.

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It is not possible to determine the maximum potential amount under these contracts due to the limited history of prior indemnification claims and the unique facts and circumstances involved in each particular agreement. 

7. Common Stock

Common Stock

Pursuant to the Company’s Third Amended and Restated Certificate of Incorporation (the amended and restated certificate of incorporation) filed in October 2019, the Company is authorized to issue 143,590,481 shares of voting common stock and 6,409,519 shares of non-voting common stock. Holders of voting common stock shall have the exclusive right to vote for the election of directors of the Company and on all other matters requiring stockholder action. Each share of the Company’s non-voting common stock may be converted at any time into one share of common stock at the option of its holder by providing 61 days written notice to the Company, subject to certain limitations, as described in the amended and restated certificate of incorporation.

2018 Stock Option and Grant Plan

In September 2018, the Company adopted the 2018 Stock Option and Grant Plan (the 2018 Plan), which provided for the Company to sell or issue common stock, or other stock-based awards, to employees, members of the board of directors and consultants of the Company. The Company generally granted stock-based awards with service conditions only (service-based awards), although there was one grant with performance conditions. As of March 31, 2021, there were no unvested options with performance conditions. Stock options granted under the 2018 Plan generally vest over three to four years. There were 1,959,411 options granted under the 2018 Plan prior to the Company’s IPO in October 2019. No further grants may be made under the 2018 Plan subsequent to the IPO.

2019 Stock Option and Incentive Plan

 The 2019 Stock Option and Incentive Plan (2019 Plan) was approved by the Company’s board of directors on October 14, 2019, and became effective on October 23, 2019. The 2019 Plan provides for the grant of incentive stock options, nonqualified stock options, stock appreciation rights, restricted stock units, restricted stock awards, unrestricted stock awards, cash-based awards and dividend equivalent rights to the Company’s officers, employees, directors and consultants. The number of shares initially reserved for issuance under the 2019 Plan was 2,342,288, and such number of shares will be increased each January 1 thereafter by 4% of the number of shares of the Company’s common stock outstanding on the immediately preceding December 31 or such lesser number of shares determined by the Company’s board of directors or compensation committee of the board of directors. On January 1, 2021, the total number of shares under the 2019 Plan was increased by 962,511 shares. As of March 31, 2021, there were 2,173,804 shares remaining available for issuance.

A summary of stock option activity is presented below:

The aggregate intrinsic value of options granted is calculated as the difference between the exercise price of the options and the estimated fair value of the Company’s common stock. The weighted average grant-date fair value of stock options granted during the three months ended March 31, 2021 and 2020 was $7.93 and $9.44, respectively.

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The fair value of each award is estimated using Black-Scholes based on the following assumptions:

Black-Scholes requires the use of subjective assumptions which determine the fair value of stock-based awards. These assumptions include:

Fair value of common stock—Prior to the Company’s IPO in October 2019, the fair value of the Company’s common stock underlying stock-based awards was estimated on each grant date by the Company’s board of directors. In order to determine the fair value of the Company’s common stock underlying stock-based awards, the Company’s board of directors considered, among other things, a valuation of the Company’s common stock prepared by an unrelated third-party valuation firm in accordance with the guidance provided by the American Institute of Certified Public Accountants Practice Guide, Valuation of Privately-Held-Company Equity Securities Issued as Compensation.

Expected term—The expected term represents the period that stock-based awards are expected to be outstanding. The expected term for option grants is determined using the simplified method, which is the midpoint between the vesting period and the contractual term of the option.

Expected volatility—As a privately held company prior to the Company’s IPO in October 2019, the Company has limited trading history for its common stock and, as such, the expected volatility is estimated based on the average volatility for comparable publicly traded biotechnology companies over a period equal to the expected term of the stock-based awards. The comparable companies were chosen based on their similar size, stage in the life cycle or area of specialty. The Company will continue to apply this process until a sufficient amount of historical information regarding the volatility of its own stock price becomes available.

Risk-free interest rate—The risk-free interest rate is based on the U.S. Treasury zero coupon issues in effect at the time of grant for periods corresponding with the expected term of a stock-based award.

Expected dividend—The Company has never paid dividends on its common stock and has no plans to pay dividends on its common stock. Therefore, the Company used an expected dividend yield of zero.

Stock-based Compensation

The Company has recorded stock-based compensation in the accompanying statements of operations as follows:

As of March 31, 2021, there was $17,450 of unrecognized compensation cost related to unvested option awards, which is expected to be recognized over a weighted-average period of 3.2 years.

2019 Employee Stock Purchase Plan

The 2019 Employee Stock Purchase Plan (2019 ESPP) was approved by the Company’s board of directors on October 14, 2019, and became effective on October 23, 2019. A total of 234,229 shares of common stock were initially reserved for issuance under the 2019 ESPP, and such number of shares will be increased each January 1 thereafter through January 1, 2029 by the least of (i) 234,229 shares of common stock, (ii) 1% of the number of shares of the Company’s common stock outstanding on the immediately preceding December 31 or (iii) such lesser number of shares determined by the 2019 ESPP’s administrator. On January 1, 2021, the total number of shares under the 2019 ESPP was increased by 234,229 shares.

Employee contributions are made through payroll deductions of up to 15% of eligible compensation over the offering period. A participant may not accrue rights to purchase more than $25 worth of the Company’s common stock for each calendar year in which

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such right is outstanding. At the end of each offering period, shares of the Company’s common stock may be purchased at 85% of the lesser of the Company’s common stock on (i) the first trading day of the relevant offering period and (ii) the last trading day of the relevant offering period. The first offering period commenced on July 1, 2020 and ended on November 30, 2020. Thereafter, offerings will be six months in duration and will commence on each December 1 and June 1.

8. Income Taxes

The Company did not record an income tax benefit in its statements of operations for the three months ended March 31, 2021 and 2020 as it is more likely than not that the Company will not recognize the federal and state deferred tax benefits generated by its losses. The Company has provided a valuation allowance for the full amount of its net deferred tax assets and liabilities as of March 31, 2021 and December 31, 2020, as management has determined it is more likely than not that any future benefit from deductible temporary differences and net operating loss and tax credit carryforwards would not be realized. The Company has not recorded any amounts for unrecognized tax benefits as of March 31, 2021 and December 31, 2020.

9. Net Loss Per Share

The Company calculates basic and diluted net loss per share attributable to common stockholders in conformity with the two-class method required for participating securities. As of March 31, 2021 and 2020, the Company had voting and non-voting common stock outstanding. Since the rights of the voting and non-voting common stock are identical, except with respect to voting, the undistributed losses of the Company have been allocated on a proportionate basis to the two classes. Diluted net loss per share is calculated using the if-converted method, which assumes conversion of all non-voting common stock to voting common stock.

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The following outstanding potentially dilutive shares have been excluded from the calculation of diluted net loss per share, as their effect is anti-dilutive:

10. Subsequent Event

In April 2021, the Company sold 671,369 shares under its at-the-market offering program (the ATM Program) for gross proceeds of $7,557, or net proceeds of $7,330, after deducting sales commissions of $227. In 2021, the Company has sold a total of 865,558 shares for gross proceeds of $9,789, or net proceeds of $9,495, after deducting sales commissions of $294 under the ATM Program.

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Item 2. Management’s Discussion and Analysis of Financial Condition and Results of Operations.

You should read the following discussion and analysis of our financial condition and results of operations together with the section entitled “Risk Factors” and our unaudited interim condensed financial statements and related notes appearing elsewhere in this Quarterly Report on Form 10-Q and with our audited financial statements and the notes thereto for the year ended December 31, 2020 included in our Annual Report on Form 10-K filed with the Securities and Exchange Commission. Some of the information contained in this discussion and analysis or set forth elsewhere in this Quarterly Report, including information with respect to our plans and strategy for our business and related financing, includes forward-looking statements that involve risks and uncertainties. As a result of many factors, including those factors set forth in the section entitled “Risk Factors,” our actual results could differ materially from the results described in or implied by the forward-looking statements contained in the following discussion and analysis. You should carefully read the section entitled “Risk Factors” to gain an understanding of the important factors that could cause actual results to differ materially from our forward-looking statements.

Overview

We are a clinical-stage biotechnology company focused on the discovery and development of engineered T cell therapies, and aiming to provide a deep and durable, perhaps curative, treatment, for patients with B cell-mediated autoimmune diseases. Our proprietary technology utilizes Chimeric AutoAntibody Receptor, or CAAR, T cells that are designed to selectively bind and eliminate only specific B cells that produce disease-causing autoantibodies, or pathogenic B cells, while sparing normal B cells. Our lead CAAR T cell product candidate was designed based on the clinically validated and commercially approved Chimeric Antigen Receptor, or CAR, T cell technology that is marketed for the treatment of B cell cancers. By harnessing the power of targeted cell therapy, we believe our CAAR T product candidates have the potential to provide responses that may be a safer and more effective option than current treatments. We believe our technology, in combination with our proprietary Cabaletta Approach for selective B cell Ablation platform, called our CABA^TM platform, has applicability across over two dozen B cell-mediated autoimmune diseases that we have identified, evaluated and prioritized. In order to accelerate product development for our lead program and to access a proven cell therapy manufacturing platform, we have entered into a collaboration with the University of Pennsylvania, or Penn. We hold multiple agreements with Penn to develop CAAR T cell therapies for the treatment of these diseases. Our goal is to leverage our team’s expertise in autoimmunity and engineered T cell therapy and our collaboration with Penn to rapidly discover and develop our portfolio of CAAR T product candidates. Our initial focus is mucosal pemphigus vulgaris, or mPV, which is an autoimmune blistering disease. We submitted an Investigational New Drug, or IND, application for our lead product candidate, DSG3-CAART, to the U.S. Food and Drug Administration, or the FDA, in August 2019 and our IND was cleared in September 2019. The FDA granted DSG3-CAART orphan drug designation for the treatment of PV in January 2020, and fast track designation for improving healing of mucosal blisters in patients with mucosal pemphigus vulgaris, or mPV, in May 2020. DSG3-CAART is being evaluated in a Phase 1 trial, or the DesCAARTes^TM trial, that is currently enrolling patients. In May 2021, we reported the acute safety data from the first cohort of patients in the DesCAARTes^TM trial, where no dose-limiting toxicities had been observed eight days after infusion in the first three patients who received DSG3-CAART. We expect to report acute safety data for the second and third cohorts during the third and fourth quarters of 2021, respectively. We also plan to announce topline target engagement data on the first patient cohort in the second half of 2021. Our lead preclinical product candidate is designed for the treatment of muscle-specific kinase myasthenia gravis, or MuSK MG, and is currently in IND enabling studies, with an IND submission planned in the second half of 2021. We are also advancing additional product candidates currently in discovery-stage or preclinical development for the treatment of mucocutaneous PV, or mcPV, PLA2R-associated membranous nephropathy, or PLA2R MN, and Hemophilia A with Factor VIII, or FVIII, alloantibodies in addition to two undisclosed targets.

We were incorporated in April 2017. In August 2018, we entered into multiple agreements with Penn to develop the CAAR T technology to treat B cell-mediated autoimmune diseases. Our operations to date have been financed primarily by net proceeds of $86.4 million from the sale of convertible notes and convertible preferred stock and net proceeds of $71.0 million from the sale of common stock in our initial public offering, or IPO, in October 2019. As of March 31, 2021, we had $102.0 million in cash and cash equivalents and investments.

Impact of the COVID-19 Pandemic

In December 2019, a novel strain of coronavirus (COVID-19) surfaced in Wuhan, China and has since reached multiple other regions and countries. The COVID-19 pandemic is evolving, and to date has led to the implementation of various responses, including government-imposed quarantines, travel restrictions and other public health safety measures, which have delayed the commencement of non-COVID-19-related clinical trials, among other restrictions.

We have been carefully monitoring the COVID-19 pandemic and its potential impact on our business and have taken important steps to help ensure the safety of employees and their families and to reduce the spread of COVID-19 community-wide. We have established a work-from-home policy for all employees, other than those performing or supporting business-critical operations, such as certain members of our laboratory staff. For those employees, we have implemented stringent safety measures designed to comply with applicable federal, state and local guidelines instituted in response to the COVID-19 pandemic. We have also maintained

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efficient communication with our partners and potential clinical sites as the COVID-19 situation has progressed. We have taken these precautionary steps while maintaining business continuity so that we can continue to progress our programs.

The extent to which COVID-19 impacts our operations or those of our third party partners will depend on future developments, which are highly uncertain and cannot be predicted with confidence, including new information that may emerge concerning the severity of COVID-19, the impact of new strains of the virus, the effectiveness and availability of vaccines and the actions to contain COVID-19 or treat its impact, among others. Our financial results through the period ending March 31, 2021 have not been significantly impacted by COVID-19, however, we cannot at this time predict the specific extent, duration, or full impact that the COVID-19 pandemic will have on our financial condition, operations, and business plans, including our ability to raise additional capital, the timing and enrollment of patients in our ongoing and planned clinical trials, future financings and other expected milestones of our product candidates.

Key Agreements

Amended and Restated License Agreement with the Trustees of the University of Pennsylvania and the Children’s Hospital of Philadelphia

In August 2018, we entered into a license agreement with Penn, which was amended and restated in July 2019 to include the Children’s Hospital of Philadelphia, or CHOP, collectively, the Institutions, and collectively with such amendment, as amended in May 2020, the License Agreement, pursuant to which we obtained (a) a non-exclusive, non-sublicensable, worldwide research license to make, have made and use products in two subfields of use, (b) effective as of October 2018, an exclusive, worldwide, royalty-bearing license, with the right to sublicense, under certain of the Institutions’ intellectual property to make, use, sell, offer for sale and import products in the same two subfields of use, and (c) effective as of October 2018, a non-exclusive, worldwide, royalty-bearing license, with limited rights to sublicense, under certain of Penn’s know-how to make, have made, use, sell, offer for sale, import and have imported products in the same two subfields of use. Our rights are subject to the rights of the U.S. government and certain rights retained by the Institutions.

Unless earlier terminated, the License Agreement expires on the expiration or abandonment or other termination of the last valid claim in Penn’s intellectual property licensed by us. We may terminate the License Agreement at any time for convenience upon 60 days written notice. In the event of an uncured, material breach, Penn may terminate the License Agreement upon 60 days written notice.

Sponsored Research Agreements

We have two sponsored research agreements, or SRAs, with Penn for the laboratories of Drs. Payne and Milone, who are also our scientific co-founders and members of our scientific advisory board. In May 2020, the agreement with Dr. Payne, or the Payne SRA, was expanded to include CAAR design and optimization efforts in three additional B cell-mediated autoimmune diseases. In August 2020, the Payne SRA was further amended to extend the term of the original research plan. In April 2021, the agreement with Dr. Milone was amended to extend the term of the original research plan. Under the amended agreements, we are committed to funding a defined research plan through February 2023. The total estimated cost of the agreements is $11.8 million, which satisfies the $2.0 million annual obligation under the License Agreement. As of March 31, 2021, $7.9 million of cost has been incurred pursuant to these agreements.

Master Translational Research Services Agreement

In October 2018, we entered into a Master Translational Services Agreement with Penn, or the Services Agreement, pursuant to which Penn agreed to perform certain services related to the research and development of the technology licensed to us under the License Agreement, as well as certain clinical, regulatory and manufacturing services.  The Services Agreement will expire on the later of (i) October 19, 2021 or (ii) completion of the services for which we have engaged Penn under the Services Agreement. Either party may terminate this agreement with or without cause upon a certain number of days’ prior written notice.  The services encompassed by the Services Agreement are performed by different organizations at Penn pursuant to certain addenda to the Services Agreement, including the Center for Advanced Retinal and Ocular Therapeutics, or CAROT, Addendum, as amended in May 2020, and the CVPF Addendum.

Components of Operating Results

Revenue

To date, we have not generated any revenue from product sales and do not expect to generate any revenue from the sales of products for several years, if at all. If our development efforts for our current or future product candidates are successful and result in

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marketing approval, we may generate revenue in the future from product sales. We cannot predict if, when or to what extent we will generate revenue from the commercialization and sale of our product candidates. We may never succeed in obtaining regulatory approval for any of our product candidates.

We may also in the future enter into license or collaboration agreements for our product candidates or intellectual property, and we may generate revenue in the future from payments as a result of such license or collaboration agreements.

Operating Expenses

Research and Development

Our research and development expenses include:

We have not reported program costs since inception because historically we have not tracked or recorded our research and development expenses on a pre-clinical program-by-program basis. We use our personnel and infrastructure resources across the breadth of our research and development activities, which are directed toward identifying and developing product candidates.

We expense all research and development costs in the periods in which they are incurred. Costs for certain research and development activities are recognized based on an evaluation of the progress to completion of specific tasks using information and data provided to us by our vendors and third-party service providers.

We expect our research and development expenses to increase substantially for the foreseeable future as we continue to invest in research and development activities related to developing our product candidates, including investments in manufacturing, as our programs advance and we conduct clinical trials. The process of conducting the necessary clinical research to obtain regulatory approval is costly and time-consuming, and the successful development of our product candidates is highly uncertain. As a result, we are unable to determine the duration and completion costs of our research and development projects or when and to what extent we will generate revenue from the commercialization and sale of any of our product candidates.

Because of the numerous risks and uncertainties associated with product development, we cannot determine with certainty the duration and completion costs of the current or future preclinical studies and clinical trials or if, when, or to what extent we will generate revenues from the commercialization and sale of our product candidates. We may never succeed in achieving regulatory approval for our product candidates. The duration, costs and timing of preclinical studies and clinical trials and development of our product candidates will depend on a variety of factors, including:

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We may never succeed in achieving regulatory approval for any of our product candidates. We may obtain unexpected results from our preclinical studies and clinical trials. We may elect to discontinue, delay or modify clinical trials of some product candidates or focus on others. A change in the outcome of any of these factors could mean a significant change in the costs and timing associated with the development of our current and future preclinical and clinical product candidates. For example, if the FDA or another regulatory authority, were to require us to conduct clinical trials beyond those that we currently anticipate will be required for the completion of clinical development, or if we experience significant delays in execution of or enrollment in any of our preclinical studies or clinical trials, we could be required to expend significant additional financial resources and time on the completion of preclinical and clinical development. We expect our research and development expenses to increase for the foreseeable future as we continue the development of product candidates.

General and Administrative Expenses

Our general and administrative expenses consist primarily of personnel costs, costs related to maintenance and filing of intellectual property, depreciation expense and other expenses for outside professional services, including legal, human resources, audit and accounting services. Personnel costs consist of salaries, benefits and stock-based compensation expense. We expect our general and administrative expenses to increase over the next several years to support our continued research and development activities, manufacturing activities, increased costs of operating as a public company and the potential commercialization of our product candidates. We anticipate our general and administrative costs will increase with respect to the hiring of additional personnel, developing commercial infrastructure, fees to outside consultants, lawyers and accountants, and increased costs associated with being a public company such as expenses related to services associated with maintaining compliance with Nasdaq listing rules and SEC requirements, insurance and investor relations costs.

Other Income

Other income consists of interest earned on our cash equivalents, amortization of bond discount or premium and investment gains and losses realized during the period.

Results of Operations for the Three Months ended March 31, 2021 and 2020

The following sets forth our results of operations for the three months ended March 31, 2021 and 2020:

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Research and Development

Research and development expenses were $6.6 million for the three months ended March 31, 2021 as compared to $4.6 million for the three months ended March 31, 2020. The table below summarizes our research and development expenses:

Specific changes in our research and development expenses year over year include a:

General and Administrative

General and administrative expenses were $3.2 million for the three months ended March 31, 2021 compared to $3.3 million for the three months ended March 31, 2020. The decrease of $0.1 million in our general and administrative expenses includes:

Other Income

Interest income decreased $0.4 million for the three months ended March 31, 2021 compared to the three months ended March 31, 2020, primarily as a result of a significant decrease in interest rates beginning in March 2020.

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Liquidity and Capital Resources

Since our inception in April 2017 through December 31, 2020, our operations have been financed by proceeds of $86.4 million from the sale of convertible notes and our convertible preferred stock and proceeds of $71.0 million from the sale of common stock in our initial public offering. As of March 31, 2021, we had $102.0 million in cash, cash equivalents and investments. Cash in excess of immediate requirements is invested in accordance with our investment policy, primarily with a view to liquidity and capital preservation.

We have incurred losses since our inception and, as of March 31, 2021, we had an accumulated deficit of $76.0 million. Our primary use of cash is to fund operating expenses, which consist primarily of research and development expenditures, and to a lesser extent, general and administrative expenditures. Cash used to fund operating expenses is impacted by the timing of when we pay these expenses, as reflected in the change in our outstanding prepaid expenses and other current assets, accounts payable and accrued expenses.

Any product candidates we may develop may never achieve commercialization and we anticipate that we will continue to incur losses for the foreseeable future. We expect that our research and development expenses, general and administrative expenses, and capital expenditures will continue to increase. As a result, until such time, if ever, as we can generate substantial product revenue, we expect to finance our cash needs through a combination of equity offerings, debt financings or other capital sources, including potentially collaborations, licenses and other similar arrangements. Our primary uses of capital are, and we expect will continue to be, compensation and related expenses, third-party clinical research, manufacturing and development services, costs relating to the build-out of our headquarters, laboratories and manufacturing facility, license payments or milestone obligations that may arise, laboratory and related supplies, clinical costs, manufacturing costs, legal and other regulatory expenses and general overhead costs.

Based upon our current operating plan, we believe that our existing cash, cash equivalents and investments as of March 31, 2021, along with proceeds from sales under our ATM Program in April 2021, will enable us to fund our operating expenses and capital expenditure requirements through at least the fourth quarter of 2022. We have based this estimate on assumptions that may prove to be wrong, and we could utilize our available capital resources sooner than we currently expect. We will continue to require additional financing to advance our current product candidates through clinical development, to develop, acquire or in-license other potential product candidates and to fund operations for the foreseeable future. We will continue to seek funds through equity offerings, debt financings or other capital sources, including potentially collaborations, licenses and other similar arrangements. However, we may be unable to raise additional funds or enter into such other arrangements when needed on favorable terms or at all. If we do raise additional capital through public or private equity offerings, the ownership interest of our existing stockholders will be diluted, and the terms of these securities may include liquidation or other preferences that adversely affect our stockholders’ rights. If we raise additional capital through debt financing, we may be subject to covenants limiting or restricting our ability to take specific actions, such as incurring additional debt, making capital expenditures or declaring dividends. Any failure to raise capital as and when needed could have a negative impact on our financial condition and on our ability to pursue our business plans and strategies. If we are unable to raise capital, we will need to delay, reduce or terminate planned activities to reduce costs.

At-The-Market Offering Sales Agreement

On November 10, 2020, we filed a registration statement on Form S-3 (File No. 333-250006) with the SEC, which was declared effective on November 18, 2020 (the Shelf Registration Statement), in relation to the registration of common stock, preferred stock, debt securities, warrants and/or units of any combination thereof for the purposes of selling, from time to time, our common stock, debt securities or other equity securities in one or more offerings. We also simultaneously entered into a Sales Agreement with Cowen and Company, LLC, to provide for the offering, issuance and sale of up to an aggregate amount of $75.0 million of our common stock from time to time in “at-the-market” offerings (the ATM Program) under the Shelf Registration Statement and subject to the limitations thereof. We will pay to the Sales Agent cash commissions of 3.0 percent of the aggregate gross proceeds of sales of common stock under the Sales Agreement. During the first quarter of 2021, we sold 194,189 shares pursuant to the ATM Program for net proceeds of $2.2 million. In April 2021, we sold an additional 671,369 shares pursuant to the ATM Program for net proceeds of $7.3 million. To date in 2021, we have sold a total of 865,558 shares pursuant to the ATM Program for gross proceeds of $9.8 million, or net proceeds of $9.5 million, after deducting sales commissions of $0.3 million.

Because of the numerous risks and uncertainties associated with research, development and commercialization of pharmaceutical products, we are unable to estimate the exact amount of our operating capital requirements. Our future funding requirements will depend on many factors, including, but not limited to:

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Further, our operating plans may change, and we may need additional funds to meet operational needs and capital requirements for clinical trials and other research and development activities. We currently have no credit facility or committed sources of capital. Because of the numerous risks and uncertainties associated with the development and commercialization of our product candidates, we are unable to estimate the amounts of increased capital outlays and operating expenditures associated with our current and anticipated product development programs.

Cash Flows

The following table summarizes our cash flows for the periods indicated:

Operating Activities

During the three months ended March 31, 2021, cash used in operating activities of $8.7 million was attributable to a net loss of $9.7 million and a net change of $0.4 million in our net operating assets and liabilities, partially offset by non-cash charges of $1.4 million from stock-based compensation and depreciation.

During the three months ended March 31, 2020, cash used in operating activities of $4.9 million was attributable to a net loss of $7.5 million partially offset by a net change of $1.7 million in our net operating assets and liabilities and non-cash charges of $0.9 million from stock-based compensation and depreciation.

Investing Activities

During the three months ended March 31, 2021, cash provided by investing activities of $2.4 million was attributable to $2.5 million of proceeds from maturities of investments, partially offset by $0.1 million of purchases of property and equipment.

During the three months ended March 31, 2020, we used $0.2 million of cash and cash equivalents in investing activities consisting of purchases of property and equipment.

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Financing Activities

During the three months ended March 31, 2021, cash provided by financing activities of $2.2 million was from sales of common stock, net of issuance costs.

During the three months ended March 31, 2020, cash used in financing activities was less than $0.1 million for payments of common stock issuance costs from our IPO in October 2019.

Contractual Obligations and Commitments

For a discussion of contractual obligations and other commitments affecting us, see the discussion under the heading “Management Discussion and Analysis of Financial Condition and Results of Operations – Contractual obligations and other commitments” included in our Annual Report on Form 10-K for the year ended December 31, 2020, as filed with the SEC on March 16, 2021.

There have been no material changes to the Company’s contractual obligations and other commitments since December 31, 2020.

Off-Balance Sheet Arrangements

During the period presented, we did not have, nor do we currently have, any off-balance sheet arrangements as defined under SEC rules.

Critical Accounting Policies and Significant Judgments and Estimates

The Critical Accounting Policies and Significant Judgments and Estimates included in our Annual Report on Form 10-K for the year ended December 31, 2020, as filed with the SEC on March 16, 2021, have not materially changed.

Emerging Growth Company Status

We are an emerging growth company, as defined in the JOBS Act. Under the JOBS Act, emerging growth companies can delay adopting new or revised accounting standards issued subsequent to the enactment of the JOBS Act until such time as those standards apply to private companies. Section 107 of the JOBS Act provides that an emerging growth company may take advantage of the extended transition period provided in Section 7(a)(2)(B) of the Securities Act of 1933 for complying with new or revised accounting standards issued subsequent to the enactment of the JOBS Act until such time as those standards apply to private companies. Section 107 of the JOBS Act provides that we can elect to opt out of the extended transition period at any time, which election is irrevocable. We have elected to use this extended transition period for complying with new or revised accounting standards that have different effective dates for public and private companies until the earlier of the date we (i) are no longer an emerging growth company or (ii) affirmatively and irrevocably opt out of the extended transition period provided in the JOBS Act. As a result, our financial statements may not be comparable to companies that comply with new or revised accounting pronouncements as of public company effective dates.

Subject to certain conditions, as an emerging growth company, we may rely on certain other exemptions and reduced reporting requirements, including without limitation (i) providing an auditor’s attestation report on our system of internal controls over financial reporting pursuant to Section 404(b) of the Sarbanes-Oxley Act and (ii) complying with any requirement that may be adopted by the Public Company Accounting Oversight Board regarding mandatory audit firm rotation or a supplement to the auditor’s report providing additional information about the audit and the consolidated financial statements, known as the auditor discussion and analysis. We will remain an emerging growth company until the earlier of (a) the last day of the fiscal year in which we have total annual gross revenue of $1.07 billion or more; (b) the last day of the fiscal year following the fifth anniversary of the date of the completion of our initial public offering; (c) the date on which we have issued more than $1.0 billion in nonconvertible debt during the previous three years; or (d) the date on which we are deemed to be a large accelerated filer under the rules of the SEC.

Recently Issued Accounting Pronouncements

In February 2016, the Financial Accounting Standards Board, or the FASB, issued ASU 2016-02, Leases (Topic 842), with guidance regarding the accounting for and disclosure of leases. The update requires lessees to recognize the liabilities related all leases, including operating leases, with a term greater than 12 months on the balance sheet. This update also requires lessees and lessors to disclose key information about their leasing transactions. This guidance was effective for public companies for annual and interim periods beginning after December 15, 2018. In June 2020, the FASB issued ASU 2020-05, Revenue from Contracts with

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Customers (Topic 606) and Leases (Topic 842), which granted a one-year effective date delay for certain companies with fiscal years beginning after December 15, 2021, and with interim periods within fiscal years beginning after December 15, 2022. Early adoption is permitted. As an Emerging Growth Company, we expect to adopt Topic 842 in 2022 and have not yet finalized the assessment of the impact that Topic 842 will have on our financial statements or financial statement disclosures.

Item 3. Quantitative and Qualitative Disclosures About Market Risk.

We are exposed to market risks in the ordinary course of our business. These risks primarily include interest rate sensitivities. We held cash and cash equivalents and investments of $102.0 million as of March 31, 2021. We generally hold our cash in interest-bearing money market treasury fund accounts and our investments are investment grade corporate bonds with high credit quality issuers. Our primary exposure to market risk is interest rate sensitivity, which is affected by changes in the general level of U.S. interest rates. Due to the short-term maturities of our cash equivalents and the low risk profile of our investments, an immediate 100 basis point change in interest rates would not have a material effect on the fair market value of our cash equivalents. Declines in interest rates, however, would reduce future investment income.

We do not have any foreign currency or derivative financial instruments. Inflation generally affects us by increasing our cost of labor and program costs. We do not believe that inflation had a material effect on our results of operations during the quarter ended March 31, 2021.

Item 4. Controls and Procedures.

Evaluation of Disclosure Controls and Procedures

Our management, with the participation of our Chief Executive Officer and Chief Financial Officer, evaluated the effectiveness of our disclosure controls and procedures (as defined in Rule 13a-15(e) and 15d-15(e) of the Securities Exchange Act of 1934, as amended, or the Exchange Act) as of the end of the period covered by this report. Based on that evaluation, our Chief Executive Officer and Chief Financial Officer concluded that our disclosure controls and procedures as of the end of the period covered by this report were effective at a reasonable assurance level in ensuring that information required to be disclosed by us in reports that we file or submit under the Exchange Act (i) is recorded, processed, summarized and reported within the time periods specified in the SEC’s rules and forms and (ii) accumulated and communicated to management, including our Chief Executive Officer and Chief Financial Officer, as appropriate, to allow timely discussions regarding required disclosure. We believe that a control system, no matter how well designed and operated, cannot provide absolute assurance that the objectives of the control system are met, and no evaluation of controls can provide absolute assurance that all control issues and instances of fraud, if any, within a company have been detected.

Changes in Internal Control over Financial Reporting

There was no change in our internal control over financial reporting (as defined in Rule 13a-15(f) and 15d-15(f) of the Exchange Act) that occurred during the fiscal quarter ended March 31, 2021 that has materially affected, or is reasonably likely to materially affect, our internal control over financial reporting. As a result of the COVID-19 pandemic, in March 2020, most of our employees began working remotely. We have not identified any material changes in our internal control over financial reporting as a result of these changes to the working environment. We are continually monitoring and assessing the COVID-19 situation to determine any potential impacts on the design and operating effectiveness of our internal controls over financial reporting.

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PART II—OTHER INFORMATION

Item 1. Legal Proceedings.

From time to time, our company may become involved in litigation or legal proceedings. While the outcome of any such proceedings cannot be predicted with certainty, as of March 31, 2021, we are not involved in any material litigation or legal proceedings that we would expect to have a material adverse impact on our financial position, results of operations, or cash flow.

Item 1A. Risk Factors.

Our business involves material and other risks, some of which are summarized and described below. You should carefully consider the risks and uncertainties described below, together with all of the other information contained in this Quarterly Report on Form 10-Q, including "Management's Discussion and Analysis of Financial Condition and Results of Operations" and the condensed financial statements and the related notes. If any of the following risks actually occur, it could harm our business, prospects, operating results and financial condition and future prospects. In such event, the market price of our common stock could decline and you could lose all or part of your investment. Additional risks and uncertainties not presently known to us or that we currently deem immaterial may also impair our business operations. This Quarterly Report on Form 10-Q also contains forward-looking statements that involve risks and uncertainties. Our actual results could differ materially from those anticipated in the forward-looking statements as a result of factors that are described below and elsewhere in this Quarterly Report.

Risks Related to Our Business, Technology and Industry

Risks Related to Clinical Development

We are early in our development efforts. If we are unable to advance our product candidates through clinical development, obtain regulatory approval and ultimately commercialize our product candidates, or experience significant delays in doing so, our business will be materially harmed.

We are early in our development efforts and we have only initiated one clinical trial to date: our DesCAARTes^TM trial in June 2020. Our ability to generate product revenues, which we do not expect will occur for many years, if ever, will depend heavily on the successful development and eventual commercialization of one or more of our product candidates. Even if we are able to develop and commercialize a marketable product, we may face challenges generating revenue from product sales. The success of our product candidates will depend on several factors, including the following:

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If we do not achieve one or more of these factors in a timely manner or at all, we could experience significant delays or be unable to successfully commercialize our product candidates, which would materially harm our business. If we do not receive regulatory approvals for our product candidates, we may not be able to continue our operations.

Cellular therapies, including our engineered CAAR T product candidates, represent a novel approach to the treatment of B cell-mediated autoimmune diseases, which creates significant challenges for us. Negative perception or increased regulatory scrutiny of any product candidates that we develop could adversely affect our ability to conduct our business or obtain regulatory approvals for such product candidates.

Cellular therapies are a novel approach and negative perception or increased regulatory scrutiny of any product candidates that we develop could adversely affect our ability to conduct our business or obtain regulatory approvals for such product candidates. Cellular therapies in general, and CAAR T cell therapies in particular, remain novel therapies, with no cellular immunotherapies licensed to date in the United States or the European Union to treat autoimmune diseases or alloimmune responses. CAAR T cell therapies may not gain the acceptance of the public or the medical community. For example, CAR Ts and other cellular therapies have in some cases caused severe side effects, including death, and their broader use may therefore be limited. Even if CAR Ts and other cellular therapies are accepted by the public and medical community in the short term, long-term adverse events observed in these therapies may increase negative perception and regulatory scrutiny. Although our CAAR Ts are different from CAR Ts and other cellular therapies, they may be viewed in the same vein, limiting their market acceptance. Public perception may be influenced by claims that gene therapy, including the insertion of a transgene, is unsafe, and products incorporating gene therapy may not gain the acceptance of the public or the medical community. The patient populations targeted by our product candidates are also typically not at risk of near-term death, even if they may suffer life-threatening symptoms, so patients will need to deem the benefits of cell therapy to be worth the risk of unknown potential adverse side effects. Our success will depend upon physicians who specialize in the treatment of B cell-mediated autoimmune diseases targeted by our product candidates prescribing treatments that involve the use of our product candidates in lieu of, or in addition to, existing treatments with which they are more familiar and for which greater clinical data may be available. Adverse events in clinical trials of our product candidates or in clinical trials of others developing similar products and the resulting publicity, as well as any other adverse events in the field of cellular therapies, could result in a decrease in demand for any product that we may develop.

We are developing a pipeline of CAAR T product candidates that are intended for use in treating individuals with B cell-mediated autoimmune disease. Advancing these novel product candidates creates significant challenges for us, including:

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In addition, preclinical murine and other animal models may not exist or be adequate for some or all of the B cell-mediated autoimmune diseases we choose to pursue in our programs, and because we are early in the clinical development process, we are unable to predict whether there may be short-term or long-term effects from treatment with any product candidates that we develop. In developing our product candidates, we have not exhaustively explored different options in the method for manufacturing CAAR T cells. We may find our existing manufacturing process may be substantially improved with future design or process changes, necessitating further clinical testing, delaying commercial launch of our first products, and causing us to incur additional expenses. For example, while we have used a lentiviral vector in our manufacturing process, we may in the future find that another viral vector or non-viral vector-based process offers advantages. Switching from one lentiviral vector to another or switching from lentiviral to another delivery system would necessitate additional process development and clinical testing, and this may delay the development of existing product candidates.

In addition, we do not know the doses to be evaluated in pivotal trials or, if licensed, commercially. Finding a suitable dose may delay our anticipated clinical development timelines. Our expectations with regard to our scalability and costs of manufacturing may vary significantly as we develop our product candidates and understand these critical factors. We may experience delays in developing a sustainable, reproducible and scalable manufacturing process or transferring that process to commercial partners, which may prevent us from completing our clinical studies or commercializing our product candidates on a timely or profitable basis, if at all.

Moreover, our product candidates may not perform successfully in clinical trials or may be associated with adverse events that distinguish them from the chimeric antigen receptor T, or CAR T, therapies that have previously been licensed. For instance, subjects in our clinical trials will be infused with our proposed therapies, and may possess strongly activating soluble antibodies, which, are not present in oncology patients and when they interact with our infused product candidates, could result in potential adverse side effects, such as CRS. Unexpected side effects or clinical outcomes would significantly impact our business. Adverse side effects caused by even one of our product candidates could negatively affect our ability to develop future product candidates based on our CABA^TM platform.

In addition, two of our current product candidates, DSG3/1-CAART and FVIII-CAART, and certain of our future product candidates may require introducing large transgenes into T cells, and lentiviral vectors may have too limited a genome capacity to accomplish this process. We currently use lentiviral vector transduction for transgene delivery. However, lentiviral vectors have a limited genome capacity that restricts the size of the transgene that can be delivered using this vector system. For example, designing a lentiviral vector that will have sufficient capacity to introduce DSG3 CAAR and DSG1 CAAR together into T cells may not be possible. In addition to reducing lentiviral vector titers that may substantially increase the cost of gene transfer, it may be entirely unsuccessful, thus necessitating use of alternative strategies for transfer of these larger transgenes into T cells.

Further, the clinical study requirements of the FDA and other regulatory agencies and the criteria they use to determine the safety, potency and purity of a product candidate are determined according to the type, complexity, novelty and intended use and market of the potential products. The regulatory approval process for novel product candidates such as ours is less clear, and can be more complex and consequently have higher development risk, be more expensive and take longer than for other, better known or extensively studied pharmaceutical or other product candidates. Approvals by the FDA for existing cell therapies treating B cell-mediated diseases, such as Kymriah (Novartis Pharmaceuticals Corporation) and Yescarta (Gilead Sciences, Inc.), may not be indicative of what the FDA may require for approval of our therapies. Approvals by any regulatory agency may not be indicative of what any other regulatory agency may require for approval or what such regulatory agencies may require for approval in connection with new product candidates. As we advance our product candidates, we will be required to consult with these regulatory agencies and comply with applicable requirements and guidelines. If we fail to do so, we may be required to delay or discontinue development of such product candidates. These additional processes may result in a review and approval process that is longer than we otherwise would have expected. More restrictive statutory regimes, government regulations or negative public opinion would have an adverse effect on our business, financial condition, results of operations and prospects and may delay or impair the development and commercialization of our product candidates or demand for any products we may develop.

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In addition, responses by agencies at the federal and state level to negative public perception or ethical concerns may result in new legislation or regulations that could limit our ability to develop or commercialize any product candidates, obtain or maintain regulatory approval or otherwise achieve profitability. The FDA has expressed interest in further regulating biotechnology products, such as cellular therapies. Agencies at both the federal and state level in the United States, as well as the U.S. Congressional committees and other government entities or governing agencies have also expressed interest in further regulating the biotechnology industry. Such action may delay or prevent commercialization of some or all of our product candidates. Adverse developments in clinical trials of cellular therapy products conducted by others may cause the FDA or other oversight bodies to change the requirements for approval of any of our product candidates. These regulatory review agencies and committees and the new requirements or guidelines they promulgate may lengthen the regulatory review process, require us to perform additional studies or trials, increase our development costs, lead to changes in regulatory positions and interpretations, delay or prevent approval and commercialization of our product candidates or lead to significant post-approval limitations or restrictions.

Patients receiving T cell-based immunotherapies, such as our product candidates, may experience serious adverse events, including neurotoxicity, CRS and killing of cells other than the intended B cells that express the autoantibodies. If our product candidates are revealed to have high and unacceptable severity and/or prevalence of side effects or unexpected characteristics, their clinical development, regulatory approval, and commercial potential will be negatively impacted, which will significantly harm our business, financial condition and prospects.

Our product candidates are CAAR T cell-based immunotherapies. There is a possibility that our product candidates could have adverse side effects, such as neurotoxicity and CRS. In other similarly designed cellular immunotherapies to treat cancer, there have been life threatening events related to severe neurotoxicity and CRS requiring intense medical intervention, such as intubation or medications to support blood pressure, and in several cases, resulted in death. Severe neurotoxicity is a condition that is currently defined clinically by cerebral edema, confusion, drowsiness, speech impairment, tremors, seizures or other central nervous system side effects, when such side effects are serious enough to lead to intensive care. CRS is a condition that is currently defined clinically by certain symptoms related to the release of cytokines, which can include fever, chills and low blood pressure, when such side effects are serious enough to lead to intensive care with mechanical ventilation or significant medications to support blood pressure.

Our product candidates may have serious and potentially fatal consequences due to the targeting of cells within the body due to unexpected protein interactions with the CAAR. Although we have completed multiple preclinical studies designed to screen for toxicity caused by unintended off-target recognition by the cell binding domain of the DSG3 CAAR, our product candidates may still recognize and react with one or more proteins unrelated to the intended surface immunoglobin target protein to which it is designed to link. If unexpected binding occurs in normal tissue, our product candidates may target and kill the normal tissue in a patient, leading to serious and potentially fatal adverse events, undesirable side effects, toxicities or unexpected characteristics. Detection of any unexpected targeting may halt or delay any ongoing clinical trials for our product candidates and prevent or delay regulatory approval. While we have developed a preclinical screening process to identify cross-reactivity of our product candidates, we cannot be certain that this process will identify all potential tissue that our product candidates may target. For example, a membrane protein array with DSG3-CAART yielded one weak signal against a protein that is designed to bind to glycoproteins and which was detected in both the test and control conditions. Further analysis of this protein in confirmatory cell-based assays repeatedly demonstrated that DSG3-CAART does not recognize nor activate against this protein. However, this further analysis may prove to be inaccurate. Any unexpected targeting that impacts patient safety could materially impact our ability to advance our product candidates into clinical trials or to proceed to marketing approval and commercialization.

Results of our studies could reveal a high and unacceptable severity and prevalence of side effects or unexpected characteristics. Undesirable side effects caused by our product candidates could cause us or regulatory authorities to interrupt, delay or halt clinical trials and could result in a more restrictive label or the delay or denial of regulatory approval by the FDA. The FDA has requested and we have agreed to provide data on the subjects dosed in Part A of our DesCAARTes^TM trial prior to dosing subjects in Part B. The FDA has communicated that the dosing of patients in Part B1 is not dependent on the review of Part A data and that they will provide feedback, if any, in a timely manner. In some cases, side effects such as neurotoxicity or CRS have resulted in clinical holds of ongoing clinical trials and/or discontinuation of the development of the product candidate. Given that the autoimmune and alloimmune diseases we are seeking to treat are, in some cases, less serious than the later stage cancers being treated with other immunotherapy products, we believe the FDA and other regulatory authorities likely will apply a different benefit-risk assessment thresholds such that even if our product candidate demonstrated a similar safety profile as current CAR T therapies, the FDA may ultimately determine that the harmful side effects outweigh the benefits and require us to cease clinical trials or deny approval of our product candidates. We believe tolerance for adverse events in the patient population being pursued with CAAR T cell therapies will be lower than it is in oncology, and the risks of negative impact from these toxicities may therefore be higher for us than for CAR T programs in oncology.

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Furthermore, treatment-related side effects could also affect patient recruitment or the ability of enrolled patients to complete the studies or result in potential product liability claims. In addition, these side effects may not be appropriately recognized or managed by the treating medical staff, as toxicities resulting from T cell-based immunotherapies are not normally encountered in routine medical care. Medical personnel may need additional training regarding T cell-based immunotherapy product candidates to understand their side effects. Inadequate training in recognizing or failure to effectively manage the potential side effects of T cell-based immunotherapy product candidates could result in patient deaths. Any of these occurrences may harm our business, financial condition and prospects significantly.

In addition to side effects caused by our product candidates, any preconditioning, administration process or related procedures, which we evaluate from time to time as part of our process improvement and optimization efforts, may also cause adverse side effects. For example, severe neurotoxicity has been noted to be associated with the use of certain lymphodepleting regimens. While we believe there are sufficient data from other CAR T programs to suggest that it is reasonable for us to initiate our first clinical trial of DSG3-CAART without a preconditioning regimen, we cannot be certain that a preconditioning regimen, with or without lymphodepleting agents, will not be required.

Although we plan to infuse DSG3-CAART without preconditioning initially in our DesCAARTes^TM trial, we may in the future use a preconditioning regimen for our CAAR T cell product candidates, which may increase the risk of adverse side effects and impact our ability to accurately assess the efficacy of our product candidates.

In oncology patients receiving CAR T cell therapy, a lymphodepleting preconditioning regimen is typically used to condition the patient prior to CAR T cell infusion in order to improve tumor immunogenicity and to promote the expansion of the infused CAR T cells. Together, these effects have been shown to enhance the clinical activity of CAR T cells in oncology patients. These regimens often include cyclophosphamide and fludarabine and are usually administered within the week prior to infusion of CAR T cells. Serious adverse events have been observed in some patients following CAR T cell infusion, and these include infection, cytokine release syndrome and neurotoxicity. The preconditioning regimen may contribute to the occurrence and severity of these adverse events due to its role in inducing lymphopenia, or low levels of lymphocytes in the blood, and enhanced CAR T cell activity.

Lymphodepleting preconditioning may not be required in all oncology settings for CAR T cell activity. A recent clinical trial in multiple myeloma patients published in 2019 in The Journal of Clinical Investigation showed similar clinical activity of CAR T cell infusions in patients with or without a lymphodepleting preconditioning regimen. Furthermore, the requirement for lymphodepleting preconditioning for potentiating engineered T cell therapy outside of oncology has not been well established. Specifically, the effect on tumor immunogenicity is not relevant in settings outside oncology, and therefore the contribution of this aspect to the potential enhancing effect of preconditioning would not apply.

In addition, a lymphodepleting regimen may eliminate pathogenic B cells targeted by our CAAR T cell product candidates. As a result, any lymphodepleting regimen for preconditioning that we use may adversely affect our ability to use DSG3 autoantibody titers, a standard clinical assay, to assess the activity of DSG3-CAART. An inability to use DSG3 autoantibody levels to demonstrate the specific activity of our CAAR T cell product candidates may require us to rely on the subjective measurement of blister formation in patients, which can be a less sensitive and accurate measurement of CAAR T cell activity. This therefore could delay efficient clinical development. As a result of these factors, including the concern that lymphodepletion may confer a potential increased safety risk to an autoimmune patient population, we believe the inclusion of such a regimen must be justified by clinical data demonstrating the need for it in the setting of autoimmune patients and is therefore difficult to justify in our first-in-human studies.

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We initiated our DesCAARTes^TM trial without a preconditioning regimen. If clinical data suggest that a preconditioning regimen is advisable, or if FDA requires that we employ a preconditioning regimen, we may employ such a regimen. If we ultimately use a preconditioning regimen, with or without lymphodepleting agents, prior to infusing patients with our CAAR T cell product candidates, our clinical patients may experience increased or more severe adverse effects specifically related to the preconditioning regimen, some of which may result in death. These undesirable side effects, whether associated with the preconditioning regimen alone or in combination with our CAAR T cell product candidates, could cause delays in patient enrollment in our clinical trials, could cause us or regulatory authorities to interrupt, delay or halt clinical trials and could result in a change to our clinical trial design, a more restrictive label or the delay or denial of regulatory approval by the FDA. Any of the foregoing may increase the duration and expense of the clinical development of our product candidates or limit market acceptance of such product candidates, if approved, any of which could have a material adverse effect on our business and financial condition. Even if we do not use a preconditioning regimen, patients may experience adverse effects related to our CAAR T cell product candidates, and our decision to design our clinical trials without preconditioning does not eliminate the risk of those side effects.

Our business is highly dependent on the success of our initial product candidates targeting B cell-mediated autoimmune diseases, particularly DSG3-CAART. All of our product candidates will require significant additional preclinical and/or clinical development before we can seek regulatory approval for and launch a product commercially.

Our business and future success depend on our ability to obtain regulatory approval of, and then successfully launch and commercialize our initial product candidates targeting B cell-mediated autoimmune diseases, including DSG3-CAART, MuSK-CAART, DSG3/1-CAART, PLA2R-CAART and others that may be selected from preclinical programs. Our product candidates are in the early stages of development and will require additional preclinical studies, clinical trials, regulatory review and licensure, substantial investment, access to sufficient commercial manufacturing capacity and significant marketing efforts before we can generate any revenue from product sales. There is no guarantee that we will be able to advance our product candidates through clinical development or obtain marketing approval for any of our product candidates. The process for obtaining marketing approval for any product candidate is very long and risky and there will be significant challenges for us to address in order to obtain marketing approval as planned, if at all.

Our IND was cleared in September 2019, and we initiated our DesCAARTes^TM trial in June 2020. We announced dosing of the first patient in this trial in December 2020. Until dosing of this patient, DSG3-CAART had only been administered in murine models, and the preclinical results we have observed may not be predictive of the results of our clinical trial or any future clinical trials. In May 2021, we announced safety data from the first three patients dosed in our clinical trial. However, the initial clinical results we have observed may not be predictive of results of subsequent cohorts in this clinical trial, or of any future clinical trials. Because DSG3-CAART is the first product candidate that we are testing in the clinic, we may experience preliminary complications surrounding trial design, protocol establishment and execution, establishing trial protocols, patient recruitment and enrollment, quality and supply of clinical doses, or safety issues. For example, while the majority of oncology CAR T clinical trials have been conducted with a lymphodepleting or other preconditioning regimen prior to infusion, we do not intend to use pre-infusion lymphodepletion or other preconditioning regimen initially in our Phase 1 trial. However, we may determine that use of a lymphodepleting or other preconditioning regimen is necessary for our product candidates to be successful, which could result in delays in clinical development and will expose patients to the associated risks.

Additionally, a failure of our clinical trial of DSG3-CAART could influence physicians’ and regulators’ opinions with regard to the viability of our CABA^TM platform more broadly, particularly if treatment-related side effects are observed. The occurrence of any of these risks could significantly harm our development plans and business prospects. If treatment-related side effects are observed with the administration of DSG3-CAART, or if it is viewed as less safe, potent or pure than other therapies, our ability to develop other CAAR T cell therapies may be significantly harmed.

We have never successfully completed any clinical trials, and we may be unable to do so for any product candidates we develop.

We have not yet demonstrated our ability to successfully complete any clinical trials, including large-scale, pivotal clinical trials, obtain regulatory approvals, manufacture a commercial scale product, or arrange for a third party to do so on our behalf, or conduct sales and marketing activities necessary for successful commercialization. Although our key employees have significant experience in leading clinical development programs, we have no experience as a company in conducting clinical trials beyond our current DesCAARTes^TM trial initiated in June 2020. Otherwise, we currently have ongoing IND-enabling studies for our MuSK-CAART program, with a planned IND submission anticipated in the second half of 2021. We may not be able to file such IND or INDs for any of our other product candidates on the timelines we expect, if at all. For example, we may experience manufacturing delays with IND-enabling studies. Moreover, we cannot be sure that submission of an IND will result in the FDA allowing further clinical trials to begin, or that, once begun, issues will not arise that require us to suspend or terminate clinical trials. Commencing each of these clinical trials is subject to finalizing the trial design based on discussions with the FDA and other regulatory authorities. Any guidance we receive from the FDA or other regulatory authorities is subject to change. These regulatory authorities could change their position, including, on the acceptability of our trial designs or the clinical endpoints selected, which may require us to complete additional clinical trials or impose stricter approval conditions than we currently expect.

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If we are required to conduct additional clinical trials or other testing of our product candidates beyond those that we currently contemplate, if we are unable to successfully complete clinical trials of our product candidates or other testing, if the results of these trials or tests are not positive or are only modestly positive or if there are safety concerns, we may:

We may not be able to file INDs to commence clinical trials on the timelines we expect, and even if we are able to, the FDA may not permit us to proceed.

We currently plan to submit our IND for our MuSK MG in the second half of 2021. This program is currently in IND-enabling studies and we are validating the manufacturing process for this program. We cannot be certain that these IND-enabling studies will be completed in a timely manner or be successful or that the manufacturing process will be validated in a timely manner. Even if we submit the IND for the MuSK MG program, the FDA may not clear the IND and allow us to begin clinical trials in a timely manner or at all. The timing of submissions on future product candidates will be dependent on further preclinical and manufacturing success. We cannot be sure that submission of an IND or IND amendment will result in the FDA allowing testing and clinical trials to begin, or that, once begun, issues will not arise that would cause us or the FDA to suspend or terminate such clinical trials. Additionally, even if such regulatory authorities agree with the design and implementation of the clinical trials set forth in an IND or clinical trial application, we cannot guarantee that such regulatory authorities will not change their requirements in the future.

Risks Related to the Current Novel Coronavirus (COVID-19) Pandemic

The COVID-19 pandemic and the future outbreak of other highly infectious or contagious diseases could seriously harm our research, development and potential future commercialization efforts, increase our costs and expenses and have a material adverse effect on our business, financial condition and results of operations.

Public health crises such as pandemics or similar outbreaks could adversely impact our business, the business operations of third parties on whom we rely and our ongoing or planned research and development activities. In December 2019, a novel strain of coronavirus surfaced in Wuhan, China and has since reached multiple other regions and countries, including Philadelphia, Pennsylvania where our primary office and laboratory space, as well as certain of our CMO partners, are located. The COVID-19 pandemic is evolving, and to date has led to the implementation of various responses, including government-imposed quarantines, travel restrictions and other public health safety measures. The extent to which COVID-19 impacts our operations or those of our third party partners will depend on future developments, which are highly uncertain and cannot be predicted with confidence, including the duration of the pandemic, new information that may emerge concerning the severity of COVID-19, the impact of new strains of the virus, the effectiveness and availability of vaccines and the actions to contain COVID-19 or treat its impact, among others.

Additionally, timely enrollment in our ongoing and planned clinical trials is dependent upon clinical trial sites which will be adversely affected by global health matters, such as COVID-19. We plan to conduct clinical trials for our product candidates in geographies which are currently being affected by COVID-19. Some factors from the COVID-19 pandemic that have delayed and could further delay or otherwise adversely affect enrollment in the clinical trials of our product candidates, as well as our business generally, include:

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These and other factors arising from the coronavirus could continue to worsen. Any of these factors, and other factors related to any such disruptions that are unforeseen, could have a material adverse effect on our business and our results of operation and financial condition. Further, uncertainty around these and related issues could lead to adverse effects on the economy of the United States and other economies, which could impact our ability to raise the necessary capital needed to develop and commercialize our product candidates.

Risks Related to the Industry

Our product candidates may cause undesirable side effects or have other properties that could halt their clinical development, prevent their regulatory approval, limit their commercial potential or result in significant negative consequences.

Undesirable or unacceptable side effects caused by our product candidates could cause us or regulatory authorities to interrupt, delay or halt clinical trials and could result in a more restrictive label or the delay or denial of regulatory approval by the FDA. Further, clinical trials by their nature utilize a sample of the potential patient population. With a limited number of subjects and limited duration of exposure, rare and severe side effects of our product candidates may only be uncovered with a significantly larger number of patients exposed to the drug. Undesirable side effects could also result in an expansion in the size of our clinical trials, increasing the expected costs and timeline of our clinical trials. Additionally, results of our clinical trials could reveal a high and unacceptable severity and prevalence of side effects or unexpected characteristics.

Licensed CAR T cell therapies and those under development have shown frequent rates of CRS and neurotoxicity, and adverse events have resulted in the death of patients. Similar adverse events could occur during treatment with our CAAR T cell product candidates. For example, activation of CAAR T cells by patient autoantibodies or alloantibodies could stimulate CRS. When CAAR T cells are infused and the CAAR binds to soluble antibodies in the blood or tissues of treated patients, these soluble antibodies may cause the CAAR T cells to proliferate, resulting in an activation of the immune system that is too high, leading to CRS. Further, it is possible that patients will exhibit acute rejection of the CAAR T cells because of preexisting immunity to the antigen within the CAAR. This could render our product candidates ineffective.

If unacceptable toxicities or health risks, including risks inferred from other unrelated immunotherapy trials, arise in the development of our product candidates, we could suspend or terminate our trials or the FDA, the Data Safety Monitoring Board, or DSMB, or local regulatory authorities such as institutional review boards, or IRBs, could order us to cease clinical trials. Regulatory authorities, such as the FDA, could also deny approval of our product candidates for any or all targeted indications. Treatment-related side effects could also affect patient recruitment or the ability of enrolled subjects to complete the trial or result in potential product liability claims. In addition, these side effects may not be appropriately recognized or managed by the treating medical staff, as toxicities resulting from T cell therapy are not normally encountered in the general patient population and by medical personnel. We expect to have to train medical personnel using CAAR T cell product candidates to understand the side effect profile of our product candidates for both our preclinical studies and clinical trials and upon any commercialization of any of our product candidates, if licensed. Inadequate training in recognizing or managing the potential side effects of our product candidates could result in patient deaths. Any of these occurrences may harm our business, financial condition and prospects significantly.

Our preclinical studies and clinical trials may fail to demonstrate the safety, potency and purity of any of our product candidates, which would prevent or delay regulatory approval and commercialization.

Before obtaining regulatory approvals for the commercial sale of any of our product candidates, we must demonstrate through lengthy, complex and expensive preclinical testing and clinical trials that our product candidates are safe, potent and pure for use in each target indication. Clinical trials are expensive and can take many years to complete, and their outcomes are inherently uncertain. Failure can occur at any time during the clinical trial process. The results of preclinical studies and early clinical trials of our product candidates may not be predictive of the results of later-stage clinical trials, including in any post-approval studies of our product candidates. In addition, initial success in any clinical trials may not be indicative of results obtained when such trials are completed. There is typically an extremely high rate of attrition from the failure of product candidates proceeding through clinical trials. Product

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candidates in later stages of clinical trials may fail to show the desired safety, potency and purity profile despite having progressed through preclinical studies and initial clinical trials.

A number of companies in the biopharmaceutical industry have suffered significant setbacks in advanced clinical trials due to lack of potency or efficacy, insufficient durability of potency or efficacy or unacceptable safety issues, notwithstanding promising results in earlier trials, and we cannot be certain that we will not face similar setbacks. These setbacks have been caused by, among other things, preclinical and other nonclinical findings made while clinical trials were underway, or safety or efficacy observations made in preclinical studies and clinical trials, including previously unreported adverse events. Moreover, preclinical and clinical data are often susceptible to varying interpretations and analyses and many companies that believed their product candidates performed satisfactorily in preclinical studies and clinical trials nonetheless failed to obtain FDA or EMA approval. Most product candidates that commence clinical trials are never approved as products.

Any preclinical studies or clinical trials that we may conduct may not demonstrate the safety, potency and purity necessary to obtain regulatory approval to market our product candidates. If the results of our ongoing or future preclinical studies and clinical trials are inconclusive with respect to the safety, potency and purity of our product candidates, if we do not meet the clinical endpoints with statistical and clinically meaningful significance, or if there are safety concerns associated with our product candidates, we may be prevented or delayed in obtaining marketing approval for such product candidates. In some instances, there can be significant variability in safety, potency or purity results between different preclinical studies and clinical trials of the same product candidate due to numerous factors, including changes in trial procedures set forth in protocols, differences in the size and type of the patient populations, changes in and adherence to the clinical trial protocols and the rate of dropout among clinical trial participants. For example, because our CAAR T cell product candidates only target approximately 0.01% to 1% of the B cells in a patient, they may not engage enough of the target to achieve adequate engraftment necessary for elimination of all pathogenic B cells. Insufficient safety or potency in clinical trials may delay product development to enable time to modify the product candidate for next generation approaches or make manufacturing changes or may lead us to discontinue development of the product candidate.

Additionally, our ongoing DesCAARTes™ trial utilizes, and our planned trials may utilize, an “open-label” trial design. An “open-label” clinical trial is one where both the patient and investigator know whether the patient is receiving the investigational product candidate or either an active drug or placebo. Most typically, open-label clinical trials test only the investigational product candidate and sometimes may do so at different dose levels. Open-label clinical trials are subject to various limitations that may exaggerate any therapeutic effect as patients in open-label clinical trials are aware when they are receiving treatment. Open-label clinical trials may be subject to a “patient bias” where patients perceive their symptoms to have improved merely due to their awareness of receiving an experimental treatment. In addition, open-label clinical trials may be subject to an “investigator bias” where those assessing and reviewing the physiological outcomes of the clinical trials are aware of which patients have received treatment and may interpret the information of the treated group more favorably given this knowledge. The results from an open-label trial may not be predictive of future clinical trial results with any of our product candidates for which we include an open-label clinical trial when studied in a controlled environment with a placebo or active control.

In addition, for DSG3-CAART, MuSK-CAART and any future trials that may be completed, we cannot guarantee that the FDA will interpret the results as we do, and more trials could be required before we submit our product candidates for approval. To the extent that the results of the trials are not satisfactory to the FDA to support a marketing application, approval of our product candidates may be significantly delayed, or we may be required to expend significant additional resources, which may not be available to us, to conduct additional trials in support of potential approval of our product candidates.

Interim, topline or preliminary data from any preclinical studies or clinical trials that we conduct may change as more data become available and are subject to audit and verification procedures that could result in material changes in the final data.

Our initial clinical trial for our lead product candidate is an open-label trial. From time to time, we may publicly disclose interim, preliminary or topline or data from our preclinical studies and clinical trials, which will be based on a preliminary analysis of then-available data, and the results and related findings and conclusions are subject to change following our receipt of additional data or a more comprehensive review of the data related to the particular study or trial. We also make assumptions, estimations, calculations and conclusions as part of our analyses of data, and we may not have received or had the opportunity to fully and carefully evaluate all data. For example, we recently disclosed preliminary safety data from the first three patients in the first dose cohort of our DesCAARTes^TM trial. While we believe the safety data observed to date is positive, the trial is in its early stages and additional data from these first three patients, data from subsequent patients and data from patients at higher dosing levels may not be positive with respect to safety or target engagement.

As a result, the topline results that we report may differ from future results of the same studies, or different conclusions or considerations may qualify such results, once additional data have been received and fully evaluated. Topline data also remain subject to audit and verification procedures that may result in the final data being materially different from the preliminary data we previously published. As a result, topline data should be viewed with caution until the final data are available. From time to time, we may also disclose interim data from planned interim analyses in our clinical trials. Interim data from clinical trials that we may complete are subject to the risk that one or more of the clinical outcomes may materially change as patient enrollment continues and more patient data become available. Adverse differences between preliminary or interim data and final data could significantly harm our business

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prospects. Further, disclosure of interim data by us or our competitors, or by patients or caregivers who are aware that a patient is receiving investigational product, due to the open-label design of the trial, could result in volatility in the price of our common stock.

Regulatory agencies, including the FDA, may not accept or agree with our assumptions, estimates, calculations, conclusions or analyses or may interpret or weigh the importance of data differently, which could impact the value of the particular program, the approvability or commercialization of the particular product candidate or product and our company in general.

If the interim, topline or preliminary data that we report differ from actual results, or if others, including regulatory authorities, disagree with the conclusions reached, our ability to obtain approval for, and commercialize, our product candidates may be harmed, which could harm our business, operating results, prospects or financial condition.

The increasing use of social media platforms presents new risks and challenges.

Social media is increasingly being used to communicate about our clinical development programs and the diseases our product candidates are being developed to treat. We intend to utilize appropriate social media in connection with communicating about our development programs. Social media practices in the biopharmaceutical industry continue to evolve and regulations relating to such use are not always clear. This evolution creates uncertainty and risk of noncompliance with regulations applicable to our business. For example, patients may use social media channels to report an alleged adverse event during a clinical trial. When such disclosures occur, there is a risk that we fail to monitor and comply with applicable adverse event reporting obligations, or we may not be able to defend our business or the public’s legitimate interests in the face of the political and market pressures generated by social media due to restrictions on what we may say about our investigational products. There is also a risk of inappropriate disclosure of sensitive information or negative or inaccurate posts or comments about us on any social networking website, or a risk that a post on a social networking website by any of our employees may be construed as inappropriate promotion. If any of these events were to occur or we otherwise fail to comply with applicable regulations, we could incur liability, face regulatory actions, or incur other harm to our business.

We may encounter substantial delays in our clinical trials or may not be able to conduct our trials on the timelines we expect or at all.

Clinical testing is expensive, time consuming and subject to uncertainty. We cannot guarantee that any clinical trials will be conducted as planned or completed on schedule, if at all. Even if these trials begin as planned, issues may arise that could suspend or terminate such clinical trials. A failure of one or more clinical trials can occur at any stage of testing, and our ongoing and future clinical trials may not be successful. Events that may prevent successful or timely completion of clinical development include:

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Any inability to successfully complete preclinical and clinical development could result in additional costs to us or impair our ability to generate revenue. In addition, if we make manufacturing or formulation changes to our product candidates, we may be required to, or we may elect to, conduct additional trials to bridge our modified product candidates to earlier versions. Clinical trial delays could also shorten any periods during which our product candidates and products, if licensed, have patent protection and may allow our competitors to bring products to market before we do, which could impair our ability to successfully commercialize our product candidates and may harm our business and results of operations.

We could also encounter delays if a clinical trial is suspended or terminated by us, by the DSMB for such trial or by the FDA or other regulatory authority, or if the IRBs of the institutions in which such trials are being conducted suspend or terminate the participation of their clinical investigators and sites subject to their review. Such authorities may suspend or terminate a clinical trial due to a number of factors, including failure to conduct the clinical trial in accordance with regulatory requirements or our clinical protocols, inspection of the clinical trial operations or trial site by the FDA or other regulatory authorities resulting in the imposition of a clinical hold, unforeseen safety issues or adverse side effects, failure to demonstrate a benefit from using a product candidate, changes in governmental regulations or administrative actions or lack of adequate funding to continue the clinical trial.

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Delays in the initiation, conduct or completion of any clinical trial of our product candidates will increase our costs, slow down our product candidate development and approval process and delay or potentially jeopardize our ability to commence product sales and generate revenue. In addition, many of the factors that cause, or lead to, a delay in the commencement or completion of clinical trials may also ultimately lead to the denial of regulatory approval of our product candidates. In the event we identify any additional product candidates to pursue, we cannot be sure that submission of an IND will result in the FDA allowing clinical trials to begin in a timely manner, if at all. Any of these occurrences may significantly harm our business, financial condition and prospects.

Monitoring safety of patients receiving our product candidates will be challenging, which could adversely affect our ability to obtain regulatory approval and commercialize our product candidates.

For our clinical trials of DSG3-CAART and our other product candidates, we expect to continue to contract with Penn and other academic medical centers and hospitals experienced in the assessment and management of toxicities arising during clinical trials. In the future, we may also contract with non-academic medical centers and hospitals with similar capabilities. Nonetheless, these centers and hospitals may have difficulty observing patients, including due to failure by patients to comply with post-clinical trial follow-up programs, and treating toxicities, which may be more challenging due to personnel changes, inexperience, shift changes, house staff coverage or related issues. This could lead to more severe or prolonged toxicities or even patient deaths, which could result in us or the FDA delaying, suspending or terminating one or more of our clinical trials, and which could jeopardize regulatory approval. We also expect the centers using DSG3-CAART and our other product candidates, if licensed, on a commercial basis could have similar difficulty in managing adverse events. Medicines used at centers to help manage adverse side effects of DSG3-CAART and our other product candidates may not adequately control the side effects and/or may have a detrimental impact on the efficacy of the treatment.

If we encounter difficulties enrolling patients in our clinical trials, our clinical development activities could be delayed or otherwise adversely affected.

We may experience difficulties in patient enrollment in our clinical trials for a variety of reasons. The timely completion of clinical trials in accordance with their protocols depends, among other things, on our ability to enroll a sufficient number of patients who remain in the trial until its conclusion. The enrollment of patients depends on many factors, including: