Notes to Unaudited Condensed Consolidated Financial Statements

Prometheus Biosciences, Inc. (the Company) was incorporated in the state of Delaware on October 26, 2016 under the name Precision IBD, Inc. and is headquartered in San Diego, California. The Company changed its name to Prometheus Biosciences, Inc. on October 1, 2019. The Company’s business is focused on the discovery, development and commercialization of novel therapeutic and companion diagnostic products for the treatment of immune-mediated diseases, starting first with inflammatory bowel disease (IBD).

In June 2019, the Company acquired Prometheus Laboratories, Inc. (PLI) and the related intangible assets used by PLI. PLI was wholly owned by Nestlé Health Science US Holdings, Inc. and the related intangible assets were owned by Societé Des Produits Nestlé S.A (together, Nestlé) (see Note 6). PLI markets and conducts several laboratory developed tests useful to gastroenterologists in monitoring their IBD patients’ disease state and informing their therapeutic decisions.

On December 31, 2020, the Company completed the spinoff of PLI by making an in-kind distribution of 100% of its interest in PLI to the Company’s stockholders of record on December 30, 2020 (see Note 6).

Reverse Stock Split

On March 5, 2021, the Company effected a one-for-ten reverse stock split of the Company’s common stock (the Reverse Stock Split). The par value and the authorized shares of the common stock were not adjusted as a result of the Reverse Stock Split. All issued and outstanding common stock and the conversion prices and ratio of the convertible preferred stock have been retroactively adjusted to reflect this Reverse Stock Split for all periods presented.

Initial Public Offering

On March 16, 2021, the Company completed its initial public offering (IPO) with the sale of 11,500,000 shares of common stock, which included the exercise in full by the underwriters of their option to purchase 1,500,000 additional shares, at an initial public offering price of $19.00 per share and received gross proceeds of $218.5 million, which resulted in net proceeds to the Company of approximately $199.8 million, after deducting underwriting discounts and commissions of approximately $15.3 million and offering-related transaction costs of approximately $3.4 million.

In addition, in connection with the completion of the IPO, all outstanding shares of convertible preferred stock were converted into 25,485,955 shares of the Company’s common stock; outstanding warrants to purchase 148,848 shares of convertible preferred stock were converted into warrants to purchase 14,884 shares of the Company’s common stock; and the Company’s certificate of incorporation was amended and restated to authorize 400,000,000 shares of common stock and 40,000,000 shares of undesignated preferred stock.

Liquidity

The Company has incurred net losses since inception, experienced negative cash flows from operations, and as of September 30, 2021, has an accumulated deficit of $159.4 million. The Company has historically financed its operations primarily through the sale of common stock and private placements of convertible preferred stock. The Company expects operating losses and negative cash flows from operations to continue for the foreseeable future. The Company believes its current capital resources will be sufficient for the Company to continue as a going concern for at least one year from the issuance date of these condensed consolidated financial statements.

The Company will be required to raise additional capital, however, there can be no assurance as to whether additional financing will be available on terms acceptable to the Company, if at all. If sufficient funds on acceptable terms are not available when needed, it would have a negative impact on the Company’s financial condition and could force the Company to delay, limit, reduce, or terminate product development or future commercialization efforts or grant rights to develop and market product candidates or testing products that the Company would otherwise plan to develop.

Basis of Presentation and Use of Estimates

The preparation of financial statements in conformity with accounting principles generally accepted in the United States (GAAP) requires management to make estimates and assumptions that impact the reported amounts of assets, liabilities, and expenses

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and the disclosure of contingent assets and liabilities in the Company’s condensed consolidated financial statements and accompanying notes. Although these estimates are based on the Company’s knowledge of current events and actions it may undertake in the future, actual results may materially differ from these estimates and assumptions.

On December 31, 2020, the Company completed the spinoff of PLI. The results of operations for the three and nine months ended September 30, 2021 have been presented as discontinued operations in the accompanying condensed consolidated financial statements in accordance with Accounting Standards Codification (ASC) 205-20, Presentation of Financial Statements—Discontinued Operations. Unless otherwise noted, discussion within these notes to the condensed consolidated financial statements relates to continuing operations (see Note 6 for additional information on discontinued operations).

On an ongoing basis, management evaluates its estimates, primarily related to revenue recognition, stock-based compensation, accrued research and development costs, and for periods prior to its IPO, the fair value of common stock, the fair value of the convertible preferred stock, and the fair value of the preferred stock purchase right liability. These estimates are based on historical data and experience, as well as various other factors that management believes to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying value of assets and liabilities that are not readily apparent from other sources. Estimates relating to the valuation of stock require the selection of appropriate valuation methodologies and models, and significant judgment in evaluating ranges of assumptions and financial inputs.

Unaudited Interim Financial Information

The unaudited financial statements at September 30, 2021, and for the three and nine months ended September 30, 2021 and 2020, have been prepared in accordance with the rules and regulations of the Securities and Exchange Commission (SEC), and with GAAP applicable to interim financial statements. These unaudited financial statements have been prepared on the same basis as the audited financial statements and include all adjustments, consisting of only normal recurring accruals, which in the opinion of management are necessary to present fairly the Company’s financial position as of the interim date and results of operations for the interim periods presented. Interim results are not necessarily indicative of results for a full year or future periods. The preparation of financial statements requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosures of contingent assets and liabilities at the date of the financial statements and the reported amounts of expenses during the reporting period. Actual results could differ materially from those estimates. These unaudited financial statements should be read in conjunction with the Company’s audited financial statements for the year ended December 31, 2020, included in the Prospectus dated March 11, 2021 filed pursuant to Rule 424(b) under the Securities Act of 1933, as amended, with the SEC on March 12, 2021.

Principles of Consolidation

The condensed consolidated financial statements include the accounts of the Company and until December 31, 2020, the date at which the spinoff was completed, its wholly-owned subsidiary, PLI, and have been prepared in conformity with GAAP. All intercompany accounts and transactions have been eliminated in consolidation.

Segment Reporting

The Company’s Chief Executive Officer, who is considered to be the chief operating decision maker (CODM), reviews financial information presented on a consolidated basis, accompanied by information about operating segments for purposes of making operating decisions and assessing financial performance. Operating segments are defined as components of an enterprise about which separate financial information is available that is evaluated regularly by the CODM in deciding how to allocate resources and in assessing performance.

Prior to the spinoff of PLI in December 2020, the Company determined its operating segments to be the therapeutics and diagnostic services businesses. The therapeutics business derives substantially all of its revenue from collaboration agreements and devotes all of its efforts to development of product candidates and companion diagnostics in the IBD space. The diagnostic services business, which is recorded as discontinued operations, derived its revenue from diagnostic services in the IBD space generated from the conduct of laboratory developed tests. Since the spinoff, the Company has operated solely within the therapeutics segment. The Company operates solely in the United States.

Cash and Cash Equivalents

The Company considers all highly liquid investments with an original maturity of three months or less when purchased to be cash equivalents. The cash and cash equivalents balance at September 30, 2021 and December 31, 2020 represents cash in readily available checking and money market accounts.

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Concentration of Credit Risk

Financial instruments, which potentially subject the Company to concentration of credit risk, consist primarily of cash, cash equivalents, and accounts receivable. The Company maintains deposits in federally insured financial institutions in excess of federally insured limits. Management believes that the Company is not exposed to significant credit risk due to the financial position of the depository institutions in which those deposits are held.

Deferred Financing Costs

At December 31, 2020, financing costs, consisting of legal, accounting, printer and filing fees related to the Company’s IPO, totaled $1.7 million.  Upon the completion of the IPO in March 2021, all of these expenses were offset against the proceeds from the IPO.

Revenue Recognition

The Company recognizes revenue in accordance with ASC Topic 606, Revenue from Contracts with Customers (ASC 606). In accordance with ASC 606, the Company performs the following steps in determining the appropriate amount of revenue to be recognized as it fulfills its obligations under each of these agreements: (i) identification of the promised goods or services in the contract; (ii) determination of whether the promised goods or services are performance obligations including whether they are distinct in the context of the contract; (iii) measurement of the transaction price, including the constraint on variable consideration; (iv) allocation of the transaction price to the performance obligations; and (v) recognition of revenue when, or as, the Company satisfies each performance obligation. At contract inception, once the contract is determined to be within the scope of ASC 606, the Company assesses the goods or services promised within each contract and determines those that are performance obligations and assesses whether each promised good or service is distinct. The Company then recognizes as revenue the amount of the transaction price that is allocated to the respective performance obligation when (or as) the performance obligation is satisfied.

To date, all of the Company’s collaboration revenue has been derived from its collaboration agreement with Millennium Pharmaceuticals, Inc., a subsidiary of Takeda Pharmaceutical Company Limited (collectively, Takeda) and its collaboration agreement with Dr. Falk Pharma GmbH as described in Note 5. The terms of these arrangements include the following types of payments to the Company: non-refundable, up-front license fees; development, regulatory and commercial milestone payments; payments for research and development services provided by the Company; and royalties on net sales of licensed products. At the initiation of an agreement, the Company analyzes whether each unit of account results in a contract with a customer under ASC 606 or in an arrangement with a collaborator subject to guidance under ASC 808, Collaborative Arrangements (ASC 808).

The Company considers a variety of factors in determining the appropriate estimates and assumptions under these arrangements, such as whether the elements are distinct performance obligations, whether there are observable stand-alone prices, and whether any licenses are functional or symbolic. The Company evaluates each performance obligation to determine if it can be satisfied and recognized as revenue at a point in time or over time. Typically, license fees, non-refundable upfront fees, and funding of research activities are considered fixed, while milestone payments are identified as variable consideration which must be evaluated to determine if it is constrained and, therefore, excluded from the transaction price. The Company estimates the amount of variable consideration using the most likely amount, as milestone payments typically only have two possible outcomes. The Company recognizes revenue for sales-based royalty promised in exchange for the license of intellectual property only when the subsequent sale occurs.

The Company may allocate transaction price using a number of methods including estimating standalone selling price of performance obligations and using the residual approach when the standalone selling price of the license is highly variable or uncertain, and observable standalone selling prices exist for the other goods or services promised in the contract.

The Company receives payments from its collaborators based on terms established in each contract. Upfront payments and other payments may require deferral of revenue recognition to a future period until the Company is unconditional. The Company does not assess whether a contract has a significant financing component if the expectation at contract inception is such that the payment by the customer is akin to a deposit for research and development services.

Research and Development and Clinical Trial Accruals

Research and development costs are charged to expense as incurred. Research and development expenses include certain payroll and personnel expenses, laboratory supplies, consulting costs, external contract research and development expenses, and allocated overhead, including rent, equipment depreciation and utilities. Advance payments for goods or services for future research and development activities are deferred and expensed as the goods are delivered or the related services are performed.

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The Company estimates preclinical studies and clinical trial expenses based on the services performed pursuant to contracts with research institutions and clinical research organizations that conduct and manage preclinical studies and clinical trials on the Company’s behalf. In addition, clinical study and trial materials are manufactured by contract manufacturing organizations. In accruing for these services, the Company estimates the time period over which services will be performed and the level of effort to be expended in each period. These estimates are based on communications with the third-party service providers and the Company’s estimates of accrued expenses and on information available at each balance sheet date. If the actual timing of the performance of services or the level of effort varies from the estimate, the Company will adjust the accrual accordingly.

Fair Value Measurements

Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. As such, fair value is a market-based measurement that should be determined based on assumptions that market participants would use in pricing an asset or liability.

Stock-Based Compensation

The Company expenses stock-based compensation to employees and non-employees over the requisite service period (usually the vesting period) on a straight-line basis, net of actual forfeitures during the period, based on the estimated grant-date fair value of the awards. The Company estimates the fair value of stock option grants using the Black-Scholes option pricing model, and the assumptions used in calculating the fair value of stock-based awards represent management’s best estimates and involve inherent uncertainties and the application of management’s judgment.

Valuation of Common Stock

Prior to the IPO, given the absence of a public trading market for the Company’s common stock, its board of directors exercised their judgment and considered a number of objective and subjective factors to determine the best estimate of the fair value of the Company’s common stock, such as: contemporaneous valuations performed by independent third-party specialists, its stage of development, including the status of its research and development efforts of its product candidates, the material risks related to its businesses and industry, its results of operations before discontinued operations and financial position, including its levels of capital resources, the prices at which its sold shares of its convertible preferred stock, the rights, preferences and privileges of its convertible preferred stock relative to those of its common stock, the conditions in the biotechnology industry and the economy in general, the stock price performance and volatility of comparable life sciences public companies, as well as recently completed mergers and acquisitions of peer companies, the likelihood of achieving a liquidity event for the holders of its common stock or convertible preferred stock, such as an IPO or a sale of the Company given prevailing market conditions, trends and developments in its industry, external market conditions affecting the life sciences and biotechnology sectors, and the lack of liquidity of its common stock, among other factors.

After the completion of the IPO, the fair value of each share of common stock is based on the closing price of the Company’s common stock as reported by Nasdaq.

Preferred Stock Purchase Right Liabilities

From time to time, the Company enters into convertible preferred stock financings where, in addition to the initial closing, investors agree to buy, and the Company agrees to sell, additional shares of that convertible preferred stock at a fixed price in the event that certain conditions are met or agreed upon milestones are achieved. The Company evaluates this purchase right and assesses whether it meets the definition of a freestanding instrument and, if so, determines the fair value of the purchase right liability and records it on the balance sheet with the remainder of the proceeds raised allocated to convertible preferred stock. The preferred stock purchase right liability is revalued at each reporting period with changes in the fair value of the liability recorded as change in fair value of preferred stock purchase right liability in the statements of operations. Upon the issuance of the shares of Series D-2 convertible preferred stock in January 2021, the preferred stock purchase right liability no longer required liability accounting and the then fair value of the preferred stock purchase right liability was reclassified into stockholders’ equity.

The Company performed the final remeasurement of the preferred stock purchase right liability as of the issuance of the shares of Series D-2 convertible preferred stock and recorded a $1.0 million change in fair value into other income (expense) for the nine months ended September 30, 2021.

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Net Loss Per Share

Basic net loss per share attributable to common stockholders is calculated by dividing the net loss attributable to common stockholders by the weighted-average number of common shares outstanding during the period. Diluted net loss per share attributable to common stockholders is computed by dividing the net loss attributable to common stockholders by the weighted-average number of common stock equivalents outstanding for the period determined using the treasury-stock method. The Company has excluded 26,641 and 36,591 weighted-average shares subject to repurchase or forfeiture from the weighted-average number of common shares outstanding for the three and nine months ended September 30, 2021, respectively, and 140,136 and 179,917 weighted-average shares subject to repurchase or forfeiture from the weighted-average number of common shares outstanding for the three and nine months ended September 30, 2020, respectively. Dilutive common stock equivalents are comprised of convertible preferred stock and options outstanding under the Company’s stock option plan.

Basic and diluted net loss attributable to common holders per share is presented in conformity with the two- class method required for participating securities as the convertible preferred stock are considered participating securities. The Company’s participating securities do not have a contractual obligation to share in the Company’s losses. As such, the net loss was attributed entirely to common stockholders. Accordingly, for the three and nine months ended September 30, 2021 and 2020, there is no difference in the number of shares used to calculate basic and diluted shares outstanding.

Potentially dilutive securities not included in the calculation of diluted net loss per share because to do so would be anti-dilutive are as follows (in common stock equivalent shares):

Recent Accounting Standards

From time to time, new accounting standards are issued by the Financial Accounting Standards Board (FASB) or other standard setting bodies and adopted by the Company as of the specified effective date. Unless otherwise discussed, the impact of recently issued standards that are not yet effective will not have a material impact on the Company’s financial position or results of operations upon adoption.

In April 2012, the Jump-Start Our Business Startups Act (the JOBS Act) was signed into law. The JOBS Act contains provisions that, among other things, reduce certain reporting requirements for an emerging growth company. As an emerging growth company, the Company may elect to adopt new or revised accounting standards when they become effective for non-public companies, which typically is later than when public companies must adopt the standards. The Company has elected to take advantage of the extended transition period afforded by the JOBS Act and, as a result, will comply with new or revised accounting standards on the relevant dates on which adoption of such standards is required for emerging growth companies, which are the dates included below.

Adoption of New Accounting Standards

In February 2016, the FASB issued Accounting Standards Update (ASU) 2016-02, Leases (Topic 842), which supersedes FASB ASC Topic 840, Leases (Topic 840), and provides principles for the recognition, measurement, presentation and disclosure of leases for both lessees and lessors. The new standard requires lessees to apply a dual approach, classifying leases as either finance or operating leases based on the principle of whether or not the lease is effectively a financed purchase by the lessee. This classification will determine whether lease expense is recognized based on an effective interest method for finance leases or on a straight-line basis over the term of the lease for operating leases. A lessee is also required to record a right-of-use asset and a lease liability for all leases with a term of greater than 12 months regardless of classification. The Company early adopted this standard on January 1, 2021 by applying the modified retrospective approach (see Note 9).  The Company made accounting policy elections to exclude leases with terms of 12 months or less from the recognition requirements and to not separate lease and non-lease components.

In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments—Credit Losses: Measurement of credit Losses on Financial Instruments (ASU 2016-13), which amends the impairment model by requiring entities to use a forward looking approach

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based on expected losses to estimate credit losses on certain types of financial instruments, including trade receivables and available-for sale debt securities. The Company early adopted this standard on January 1, 2021 by applying the modified retrospective approach and determined there was no cumulative-effect transition adjustment required to the opening balance of accumulated deficit for the recognition of additional credit losses upon adoption of this standard based on its outstanding accounts receivable, the composition and credit quality of its short-term investments, and current economic conditions as of that date.

In August 2020, the FASB issued ASU No. 2020-06, Debt – Debt with Conversion and Other options (Subtopic 470-20) and Derivative and Hedging – Contracts in Entity’s Own Equity (Subtopic 815-40). The amendments in this ASU reduce the number of accounting models for convertible debt instruments and convertible preferred stock, as well as, amend the guidance for the derivatives scope exception for contracts in an entity’s own equity to reduce form-over-substance-based accounting conclusion. In addition, this ASU improves and amends the related EPS guidance. The amendments in this ASU are effective for the Company on January 1, 2024, including interim periods within those fiscal years. The Company early adopted this standard on January 1, 2021 by applying the modified retrospective approach.  The adoption of ASU 2020-06 had no material impact on the Company’s condensed financial statements and accompanying footnotes.

The accounting guidance defines fair value, establishes a consistent framework for measuring fair value and expands disclosure for each major asset and liability category measured at fair value on either a recurring or nonrecurring basis. Fair value is defined as an exit price, representing the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. As such, fair value is a market-based measurement that should be determined based on assumptions that market participants would use in pricing an asset or liability. As a basis for considering such assumptions, the accounting guidance establishes a three-tier fair value hierarchy, which prioritizes the inputs used in measuring fair value as follows:

Assets and liabilities measured at fair value are classified in their entirety based on the lowest level of input that is significant to the fair value measurement. The Company’s assessment of the significance of a particular input to the fair value measurement in its entirety requires management to make judgments and consider factors specific to the asset or liability.

The carrying amounts of cash and cash equivalents, prepaid and other assets, accounts payable and accrued liabilities are considered to be representative of their respective fair values because of the short-term nature of those instruments. Based on the borrowing rates currently available to the Company for loans with similar terms, which is considered a Level 2 input, the Company believes that the fair value of long-term debt approximates its carrying value.

The Company’s financial instruments that are carried at fair value consist of Level 3 liabilities. There were no transfers within the hierarchy during the three and nine months ended September 30, 2021 and 2020. At December 31, 2020, Level 3 liabilities that were measured at fair value on a recurring basis consisted of warrants to purchase shares of convertible preferred stock and a preferred stock purchase right liability. The Company had no Level 3 liabilities at September 30, 2021 as the liabilities for the warrants to purchase shares of convertible preferred stock and the preferred stock purchase right was remeasured and reclassified to stockholders’ equity upon the closing of the Company’s IPO in March 2021 and the issuance of shares of Series D-2 convertible preferred stock in January 2021, respectively.

Convertible Preferred Stock Warrant Liability

The convertible preferred stock warrant liability was recorded at fair value utilizing the Black-Scholes option pricing model using significant unobservable inputs consistent with the inputs used for the Company’s stock-based compensation expense adjusted for the preferred stock warrants’ expected term and the fair value of the underlying preferred stock.

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The assumptions used in the Black-Scholes option pricing model to determine the fair value of the convertible preferred stock warrant liability at the date of the IPO and December 31, 2020 were as follows:

Preferred Stock Purchase Right Liability

At December 31, 2020, the preferred stock purchase right liability was determined using a valuation model that considered: (i) the risk-free rate commensurate with the expected milestone timing of 0.09%; (ii) the probability of the Series D-2 tranche of 80.0%; (iii) volatility of 80.0%; (iv) consideration received for the Series D-1 preferred stock; (v) the number of shares to be issued to satisfy the preferred stock purchase right and at what price; and (vi) certain implied and provided assumptions needed to calibrate the Series D-1 value and the Series D-2 purchase right. Upon the issuance of the shares of Series D-2 convertible preferred stock in January 2021, the liability was remeasured and as a result of closing the sale of shares of Series D-2 convertible preferred stock, a charge of $1.0 million was recorded in the statement of operations for the nine months ended September 30, 2021.  

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Depreciation expense related to property and equipment was $0.1 million and $29,000 for the three months ended September 30, 2021 and 2020, respectively, and $0.2 million and $0.1 million for the nine months ended September 30, 2021 and 2020, respectively.

Cedars-Sinai Medical Center

In September 2017, the Company entered into an Exclusive License Agreement with Cedars-Sinai Medical Center (Cedars-Sinai), a related party, as amended and restated (the Cedars-Sinai Agreement). Under the terms of the Cedars-Sinai Agreement, Cedars-Sinai granted the Company an exclusive, worldwide, royalty bearing license with respect to certain patent rights, information and materials related to therapeutic targets and companion diagnostic products, in each case to conduct research, develop, and commercialize therapeutic and diagnostic products for human use. The licensed technology includes information and materials arising out of Cedars-Sinai’s database and biobank, as well as exclusive access to this database and biobank, which is an integral part of the Company’s Prometheus360 platform.  In August 2021, the Company and Cedars-Sinai amended and restated the Cedars-Sinai Agreement to, among other things, add a joint steering committee and cover new intellectual property.

As consideration for the license rights, in September 2017 the Company issued (i) 257,500 shares of fully vested common stock, and (ii) 335,000 shares of unvested restricted common stock, all of which is vested as of December 31, 2020. The fair value of all of the shares were measured at the date of issuance. Additionally, the Company is obligated to pay Cedars-Sinai low- to mid-single digit percentage royalties on net sales of products covered under the Cedars-Sinai Agreement. In 2017, the Company and Cedars-Sinai also entered into Research agreements, under which the parties can provide research services to each other at pricing specified in individual statements of work. During the three and nine months ended September 30, 2021 and 2020, no services were provided under the agreements.

Collaboration Agreement with Millennium Pharmaceuticals, Inc., a subsidiary of Takeda Pharmaceutical Company Limited

In March 2019, the Company entered into a Companion Diagnostics Development and Collaboration Agreement (the Takeda Agreement) with Millennium Pharmaceuticals, Inc., a wholly-owned subsidiary of Takeda, pursuant to which the Company agreed to develop a companion diagnostic product for certain drug targets selected by Takeda, and Takeda agreed to develop and commercialize any therapeutic clinical candidates that it develops directed against any selected drug targets for the treatment of IBD (Takeda Drugs).

In consideration of the rights granted to Takeda under the Takeda Agreement, the Company received a one-time upfront payment of $1.5 million and is eligible to receive, for any targets selected by Takeda, future development and regulatory milestone payments of up to $47.9 million, commercial milestone payments of up to $25.0 million, sales milestone payments of up to $75.0 million, and low-single digit percentage royalties on net sales of all Takeda Drugs, subject to the terms and conditions set forth in the Takeda Agreement. 

At inception and through September 30, 2021, the Company has identified one performance obligation per each target for all the deliverables under the agreement since the delivered elements are not distinct within the context of the contract. Accordingly, the Company will recognize revenue for the transaction price in an amount proportional to the collaboration expenses incurred and the total estimated collaboration expenses over the four-year period over which it expects to satisfy its performance obligations. The Company included one milestone in the transaction price as it was deemed not probable of significant reversal at the inception of the agreement. Due to the uncertainty in the achievement of the developmental and commercial milestones, the variable consideration associated with these future milestone payments has been fully constrained (excluded) from the transaction price until such time that the Company concludes that it is probable that a significant reversal of previously recognized revenue will not occur. These estimates will be re-assessed at each reporting period. In connection with the Takeda Agreement, the Company recognized revenue of $0.1 million and $0.2 million for the three months ended September 30, 2021 and 2020, respectively, and $0.3 million and $0.6

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million for the nine months ended September 30, 2021 and 2020, respectively, and had deferred revenue of $1.2 million, $1.7 million as of September 30, 2021 and December 31, 2020, respectively. The Company expects to recognize $0.2 million of the deferred revenue balance during the remainder of 2021.

Dr. Falk Pharma GmbH Collaboration Agreement

In July 2020, the Company entered into a Co-Development and Manufacturing Agreement (the Falk Agreement) with Dr. Falk Pharma GMBH (Falk), pursuant to which the parties agreed to co-develop and commercialize, exclusively in their respective territories, therapeutic product candidates targeting members of the TNF super family for the treatment of UC and CD under the Company’s PR600 program. Under the Falk Agreement, the Company is responsible for regulatory approvals and commercialization of any products in the United States and the rest of the world, other than the Falk territory. Falk is responsible for regulatory approvals and commercialization of any products in the European Union, United Kingdom, Switzerland, the countries of the European Economic Area (excluding Malta and the Republic of Cyprus), Australia and New Zealand (Falk territory).

In consideration of the rights granted to Falk under the Falk Agreement, the Company received a one-time upfront payment of $2.5 million upon execution of the Falk Agreement in July 2020, and has received two subsequent preclinical development milestone payments of $2.5 million and $10.0 million. The first development milestone payment was paid when the underlying development plan was finalized in December 2020. The second development milestone payment was paid upon selection of a clinical candidate for the Company’s PR600 program in June 2021. The Company remains eligible to receive an additional preclinical development milestone payment of $5.0 million and low-single to low-double digit percentage royalties on net sales of all products incorporating antibodies covered by the agreement in the Falk territory, subject to the terms of the Falk Agreement. The Company agreed to pay Falk a low-single digit royalty on net sales for such products in the Company’s territory. Falk agreed to fund 25% of the Company’s third-party development costs set forth in the development plan. 

At inception and through September 30, 2021, the Company has identified one performance obligation for all the deliverables under the Falk Agreement. Accordingly, the Company is recognizing revenue for the transaction price allocated to the performance obligation in an amount proportional to the collaboration expenses incurred and the total estimated collaboration expenses over the seven year period over which it expects to satisfy its performance obligation. The Company included the upfront payment and all milestone payments in the transaction price as it was deemed not probable of significant reversal at the inception of the agreement. In connection with the Falk Agreement, the Company recognized revenue of $0.2 million and $0.2 million for the three and nine months ended September 30, 2020, respectively, $0.9 million and $1.8 million for the three and nine months ended September 30, 2021, respectively, and had deferred revenue of $14.1 million and $4.8 million as of September 30, 2021 and December 31, 2020, respectively. This deferred revenue balance is expected to be recognized proportionally as expenses are incurred over the estimated seven-year term. The Company expects to recognize $1.0 million of the deferred revenue balance during the remainder of 2021.

A reconciliation of deferred revenue related to the Takeda Agreement and the Falk Agreement for the nine months ended September 30, 2021 is as follows (in thousands):

On June 30, 2019, the Company acquired 100% of the common stock of PLI and the related intangible assets used by PLI for total consideration of approximately $31.7 million, consisting of the issuance of 16.5 million shares of the Company’s Series C convertible preferred stock with a fair value of $16.5 million, the present value of $15.0 million in deferred cash payments due as follows: $5.0 million due on June 30, 2020 and $10.0 million due on June 30, 2021, and acquisition-related contingent consideration consisting of 3,500,000 shares of the of the Company’s Series C convertible preferred stock with a fair value of $3.5 million. The deferred cash payments totaling $15.0 million were not contingent upon any event and to reflect the interest component were discounted at 12%. In June 2020, $5.0 million of deferred cash payments were converted to 5,000,000 shares of Series C convertible preferred stock and in October 2020, $3.8 million of deferred cash payments were converted to 5,088,851 shares of Series D convertible preferred stock. In addition, in January 2021, $6.1 million of deferred cash payments were converted to 7,219,560 shares of Series D-2 shares of convertible preferred stock. As of September 30, 2021 and December 31, 2020, a total of $0 and $5.7 million, respectively, is recorded as Amounts due to Nestlé, current—related party in the accompanying condensed consolidated balance

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sheets. The acquisition-related contingent consideration stipulated certain revenue thresholds for the Anser^® test during the first calendar year following the acquisition. The shares were released from escrow on June 30, 2020.

In December 2020, in order to achieve the Company’s strategic objectives, the Company’s board of directors approved the spinoff of PLI by making an in-kind distribution of 100% of its interest in PLI to the Company’s stockholders of record on December 30, 2020. In connection with the spinoff, which was effected on December 31, 2020, the Company assigned PLI specific intellectual property to PLI; entered into a transition services agreement whereby the Company agreed to provide PLI with certain transition services including general and administrative, finance and clinical operations support; and entered into a sublease agreement under which the Company will continue to occupy approximately 40,000 square feet in the PLI facility for a term of one year, with an option to renew for an additional year. Post spinoff, the Company retained obligations under the Oxford Loan (see Note 7) and for the deferred cash payments to Nestlé.

The major line items constituting the loss of PLI for the three and nine months ended September 30, 2020, which are reflected in the accompanying condensed consolidated statements of operations as discontinued operations, are as follows:

Commitments and Contingencies

At the acquisition date, PLI was involved with several legal proceedings and claims against it. All claims against PLI remained obligations of PLI and effective upon the spinoff, the Company has no remaining obligations with respect to these claims.

In January 2020, the Company entered into a Loan and Security Agreement (the Loan Agreement) with Oxford Finance LLC and its affiliates (Oxford) (the Oxford Loan) which provided for total borrowings of up to $25.0 million, of which $7.5 million was drawn upon execution of the agreement. Interest accrued at an annual rate at the greater of (a) the 30-day U.S. LIBOR rate reported the last business day of the month that immediately precedes the month in which the interest will accrue, or (b) 2.01%, plus 5.98%, with a minimum annual rate of 7.99%. From March 1, 2020 through February 28, 2023, the Company was required to make interest only payments. Beginning March 1, 2023, in addition to interest payments, the monthly payments were to include an amount equal to the outstanding principal divided by 24 months. At maturity (or earlier prepayment), the Company was also required to make a final payment equal to 4.0% of the original principal amount borrowed and 3% of the future amount to be funded.

The Oxford Loan was collateralized by a first priority security interest in substantially all of the Company’s current and future assets, other than its intellectual property, and contains customary conditions of borrowing, events of default and covenants, including covenants that restricted the Company’s ability to dispose of assets, merge with or acquire other entities, incur indebtedness and make distributions to holders of the Company’s capital stock. Should an event of default occur, including the occurrence of a material adverse change, the Company could have been liable for immediate repayment of all obligations under the Oxford Loan. In December 2020, the Oxford Loan Agreement was amended to allow the PLI spinoff and to release PLI from all obligations pursuant to the Oxford Loan.

In addition, warrants to purchase 112,500 shares of Series C convertible preferred stock were issued to Oxford in conjunction with the execution of the agreement at an exercise price of $1.00 per share. The warrants have a ten-year life and are exercisable immediately. The warrant became exercisable for an aggregate of 14,884 shares of the Company’s common stock at an exercise price

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of $7.558 per share upon the completion of the IPO. The fair value of the warrant, the debt issuance costs and the final payment totaling approximately $0.6 million were amortized to interest expense using the effective interest method over the term of the debt.

In July 2021, the Company voluntarily prepaid the aggregate outstanding principal balance of $7.5 million plus an additional $0.5 million consisting of the prepayment penalty, accrued interest, and final payment due under the terms of the Oxford Loan, and the Loan Agreement was terminated in accordance with its terms. All liens and security interests securing the Oxford Loan were released upon termination. The Company recognized a $0.6 million loss on extinguishment on the Company’s condensed consolidated statements of operations for the three and nine months ended September 30, 2021.

Amended Certificate of Incorporation

In March 2021, the Company amended its Certificate of Incorporation to authorize 400,000,000 shares of common stock and 40,000,000 shares of preferred stock.

Convertible Preferred Stock

In connection with the completion of the Company’s IPO on March 16, 2021, all outstanding shares of convertible preferred stock were converted into 25,485,955 shares of the Company’s common stock and outstanding warrants to purchase 148,848 shares of convertible preferred stock were converted into warrants to purchase 14,884 shares of the Company’s common stock.

As of December 31, 2020, the Company’s convertible preferred stock was classified as temporary equity on the accompanying balance sheet in accordance with authoritative guidance for the classification and measurement of potentially redeemable securities whose redemption is based upon certain change in control events outside of the Company’s control.

Series C Convertible Preferred Stock

In March 2020, the Company sold 28,063,500 shares of Series C convertible preferred stock and received net cash proceeds totaling $28.0 million.

Series D Convertible Preferred Stock

In October 2020, the Company entered into a Series D convertible preferred stock purchase agreement (Series D SPA) under which it issued 61,066,216 shares of Series D-1 convertible preferred stock, for cash, at a price of $0.7558 per share, for net proceeds of $46.2 million (the Initial Series D Closing). In addition, 5,088,851 shares of Series D-1 convertible preferred stock were issued to Nestlé in satisfaction of a deferred purchase price obligation of $3.8 million. The Series D SPA contained provisions that potentially obligated the Company to issue an additional 94,007,051 shares of Series D-2 convertible preferred stock at $0.8510 per share in an additional closing, 7,231,311 of which was issuable to Nestlé for satisfaction of deferred purchase price obligations of $6.2 million, upon the approval by the Company’s board of directors, or at the option of the investors who participated in the Initial Series D Closing, or upon the achievement of certain milestones as defined in the Series D SPA, which purchase right terminates upon certain specified events, including an initial public offering of the Company, if any.

The Company determined its obligation to issue additional shares of the Company’s Series D-2 convertible preferred stock in the Initial Series D Closing represented a freestanding financial instrument that required liability accounting. This freestanding preferred stock purchase right liability for the additional closing was recorded at fair value, with changes in fair value recognized in the statements of operations. As of the Initial Series D Closing, the estimated fair value of the preferred stock purchase right liability was $3.9 million. In January 2021, 93,995,300 shares of Series D-2 convertible preferred stock were issued, of which, 7,219,560 were issued to Nestlé for the satisfaction of deferred purchase price obligations of $6.1 million.  Upon the closing of the sale of these shares, the preferred stock purchase right liability was remeasured to fair value and the change in fair value of $1.0 million was recorded in the statement of operations for the three and nine months ended September 30, 2021. The liability was then reclassified to stockholders’ equity.

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The authorized, issued and outstanding shares of convertible preferred stock as of December 31, 2020 consisted of the following (in thousands, except share and per share amounts):

Equity Incentive Plans

In 2017, the Company adopted the 2017 Equity Incentive Plan (the 2017 Plan), which as amended, had 5,524,354 shares of common stock reserved for issuance. Under the 2017 Plan, the Company could grant stock options, stock appreciation rights, restricted stock, restricted stock units and other awards to individuals who are employees, non-employee directors or consultants of the Company or its subsidiaries. The maximum term of the options granted under the 2017 Plan was no more than ten years. Grants generally vested at 25% one year from the vesting commencement date and ratably each month thereafter for a period of 36 months, subject to continuous service. The 2017 Plan allowed for the early exercise of all stock options granted if authorized by the board of directors at the time of grant.

In February 2021, the board of directors adopted, and the Company’s stockholders approved, the 2021 Incentive Award Plan (the 2021 Plan), which became effective in connection with the IPO. Pursuant to the 2021 Plan, the Company ceased granting awards under the 2017 Plan. Under the 2021 Plan, the Company may grant stock options, restricted stock, dividend equivalents, restricted stock units, stock appreciation rights, and other stock or cash-based awards to individuals who are then employees, officers, non-employee directors or consultants of the Company. The number of shares initially available for issuance under awards granted pursuant to the 2021 Plan is the sum of (1) 3,600,000 shares of common stock, plus (2) any shares subject to outstanding awards under the 2017 Plan as of the effective date of the 2021 Plan that become available for issuance under the 2021 Plan thereafter in accordance with its terms. In addition, the number of shares of common stock available for issuance under the 2021 Plan will be increased annually on the first day of each fiscal year during the term of the 2021 Plan, beginning with the 2022 fiscal year, by an amount equal to the lesser of (a) 5% of the shares of common stock outstanding on the final day of the immediately preceding calendar year or (b) such smaller number of shares as determined by the Company’s board of directors. At September 30, 2021, 3,074,775 shares remain available for issuance under the 2021 Plan.

The Company’s stock option activity for the nine months ended September 30, 2021 is summarized in the following table: