Protagonist Therapeutics PTGX Form 10-Q filing Q2 FY2026

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PART I. – FINANCIAL INFORMATION

Item 1. Condensed Consolidated Financial Statements (unaudited)

**ITEM 1.**FINANCIAL STATEMENTS

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

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

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

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PROTAGONIST THERAPEUTICS, INC.

Condensed Consolidated Statements of Stockhold****ers’ Equity

(Unaudited)

(In thousands, except share data)

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

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PROTAGONIST THERAPEUTICS, INC.

Condensed Consolidated Statements of Stockholders’ Equity

(Unaudited)

(In thousands, except share data)

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

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PROTAGONIST THERAPEUTICS, INC.

Condensed Consolidated Statements of Cash Flows

(Unaudited)

(In thousands)

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

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PROTAGONIST THERAPEUTICS, INC.

Notes to Unaudited Condensed Consolidated Financial Statements

**Note 1.**Organization and Description of Business

Protagonist Therapeutics, Inc. (the “Company”) is a discovery through late-stage development biopharmaceutical company with a proprietary technology platform that enables de novo discovery of peptide therapeutics. The Company’s programs fall into three broad therapeutic areas: (i) inflammation and immunology (“I&I”), (ii) hematology and (iii) metabolic diseases. The Company’s aim is to develop medicines for biologically and commercially validated targets which demonstrate a strong differentiation compared to existing therapies.

ICOTYDE™ (icotrokinra) was approved in the United States in March 2026 for the treatment of moderate-to-severe plaque psoriasis in adults and pediatric patients 12 years of age or older who weigh at least 40 kg and are candidates for systemic therapy or phototherapy. ICOTYDE is the first and only targeted oral peptide that precisely blocks the Interleukin-23 receptor (“IL-23R”) and is licensed to Janssen Biotech, Inc., a Johnson & Johnson company (“JNJ”). ICOTYDE was jointly discovered by the Company and JNJ scientists, with the Company having primary responsibility for the development of ICOTYDE through Phase 1, and JNJ assuming responsibility for further development and commercialization. In September 2025, JNJ submitted an application to the European Medicines Agency (“EMA”) seeking the first approval of ICOTYDE for the treatment of adults and pediatric patients 12 years of age and older with moderate-to-severe plaque psoriasis. ICOTYDE is in Phase 3 development for psoriatic arthritis and ulcerative colitis, and in Phase 2b/3 for Crohn’s disease.

Rusfertide, a first-in-class investigational injectable mimetic of the natural hormone hepcidin, is currently in development for the treatment of the rare blood disorder polycythemia vera (“PV”). Rusfertide is licensed to Takeda Pharmaceuticals Inc. (“Takeda”). The Company discovered and led development for rusfertide through Phase 3, and Takeda is responsible for further development and commercialization. In August 2025, rusfertide was granted Breakthrough Therapy designation by the U.S. Food and Drug Administration (the “FDA”) for the treatment of erythrocytosis in patients with PV. In December 2025, a New Drug Application (“NDA”) was submitted to the FDA by Takeda and the Company seeking the first approval of rusfertide for the treatment of adults with PV. The NDA was granted priority review by the FDA, with a Prescription Drug User Fee Act target action date in August 2026.

The Company also has a number of clinical and pre-clinical programs addressing biologically and commercially validated targets, including IL-17 oral peptide antagonist PN-881, obesity triple agonist peptide PN-477, obesity dual agonist peptide PN-458, oral small molecule hepcidin functional mimetic PN-8047, and IL-4 and amylin programs.

The Company is headquartered in Newark, California and has one wholly owned subsidiary, Protagonist Pty Limited (“Protagonist Australia”), located in Brisbane, Queensland, Australia.

Note 2. Summary of Significant Accounting Policies

Basis of Presentation and Consolidation

The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with generally accepted accounting principles in the United States (“GAAP”), the instructions to Form 10-Q and Rule 10-01 of Regulation S-X and applicable rules and regulations of the Securities and Exchange Commission (“SEC”) regarding interim financial reporting. As permitted under those rules, certain footnotes or other financial information that are normally required by GAAP have been condensed or omitted and, accordingly, the condensed consolidated balance sheet as of June 30, 2026 has been derived from the Company’s unaudited consolidated financial statements at that date but does not include all of the information required by GAAP for complete consolidated financial statements. These unaudited interim condensed consolidated financial statements have been prepared on the same basis as the Company’s annual consolidated financial statements and, in the opinion of management, reflect all adjustments (consisting of normal recurring adjustments) that are necessary for a fair presentation of the Company’s condensed consolidated financial statements. The results of operations for the three and six months ended June 30, 2026 are not necessarily indicative of the results to be expected for the year ending December 31, 2026 or for any future period.

The accompanying unaudited condensed consolidated financial statements and related financial information should be read in conjunction with the audited consolidated financial statements and the related notes thereto for the year ended December 31, 2025 included in the Company’s Annual Report on Form 10-K, filed with the SEC on February 25, 2026.

Principles of Consolidation

The accompanying unaudited interim condensed consolidated financial statements include the accounts of the Company and its wholly owned subsidiary. All intercompany transactions and balances have been eliminated upon consolidation.

Use of Estimates

The preparation of the condensed consolidated financial statements in conformity with GAAP requires management to make estimates, assumptions and judgments that affect the reported amounts of assets and liabilities and disclosure of contingent liabilities as of the date of the condensed consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. On an ongoing basis, management evaluates its estimates, including those related to revenue recognition, accruals for research and development activities, stock-based compensation, income taxes, marketable securities and leases. Estimates related to revenue recognition include assumptions used to determine standalone selling price utilized to allocate the transaction price between distinct performance obligations, assumptions used to recognize revenue over time for certain performance obligations for which a cost-based input method is used as the measure of progress, estimates of whether contingent consideration should be included in the transaction price at each reporting period, and estimates related to royalty revenue recognition. Management bases these estimates on historical and anticipated results, trends, and various other assumptions that the Company believes are reasonable under the circumstances, including assumptions as to forecasted amounts and future events. Actual results may differ materially from these estimates.

There has been uncertainty and disruption in the global economy and financial markets due to a number of factors, including but not limited to geopolitical instability and changes in trade policies, including tariffs or other trade restrictions or the threat of such actions and retaliatory actions. The Company’s business may also be impacted by changes or disruptions at the FDA and other government agencies. The Company has taken into consideration any known impacts to its accounting estimates to date and is not aware of any additional specific events or circumstances that would require any additional updates to its estimates or judgments or a revision of the carrying value of its assets or liabilities as of the filing date of this Quarterly Report on Form 10-Q. These estimates may change as new events occur and additional information is obtained. Actual results could differ materially from these estimates under different assumptions or conditions.

Cash as Reported in Condensed Consolidated Statements of Cash Flows

Cash as reported in the condensed consolidated statements of cash flows includes the aggregate amounts of cash and cash equivalents and restricted cash as presented on the condensed consolidated balance sheets.

Cash as reported in the condensed consolidated statements of cash flows consisted of (in thousands):

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Restricted cash as of June 30, 2026 and 2025 consists of a cash deposit held as security in connection with a letter of credit related to the Company’s facility lease entered into in March 2017, as subsequently amended, and a cash deposit held as security in connection with the issuance of a bank guarantee in May 2025 to maintain the active status of the Company’s value-added tax registration.

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Stock-Based Compensation Expense

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The Company has granted stock options, restricted stock units (“RSUs”) and performance stock units (“PSUs”).

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Stock-based compensation expense associated with stock options is based on the estimated grant date fair value using the Black-Scholes valuation model, which requires the use of assumptions related to expected stock price volatility, option term, risk-free interest rate and dividend yield. The Company recognizes compensation expense over the vesting period of the awards that are ultimately expected to vest.

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Stock-based compensation expense associated with RSUs is based on the fair value of the Company’s common stock on the grant date, which equals the closing market price of the Company’s common stock on the grant date. For RSUs, the Company recognizes compensation expense over the vesting period of the awards that are ultimately expected to vest.

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PSUs allow the recipients of such awards to earn fully vested shares of the Company’s common stock upon the achievement of pre-established performance objectives. Stock-based compensation expense associated with PSUs is based on the fair value of the Company’s common stock on the grant date, which equals the closing market price of the Company’s common stock on the grant date and is recognized when the performance objective is expected to be achieved. The Company evaluates the probability of achieving the performance criteria on a quarterly basis. The cumulative effect on current and prior periods of a change in the estimated number of PSUs expected to be earned is recognized as compensation expense or as reduction of previously recognized compensation expense in the period of the revised estimate. No stock-based compensation related to PSUs was recognized for the three and six months ended June 30, 2026 and the three months ended June 30, 2025. The Company recognized $1.8 million of stock-based compensation expense related to PSUs for the six months ended June 30, 2025.

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The Company recognizes forfeitures of stock-based awards as they occur.

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Total stock-based compensation expense was as follows (in thousands):

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Significant Accounting Policies

There have been no material changes to the Company’s significant accounting policies during the three and six months ended June 30, 2026, as compared to those disclosed in Note 2. Summary of Significant Accounting Policies included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2025.

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Recently Issued Accounting Pronouncements Not Yet Adopted as of June 30, 2026

In December 2025, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2025-11 Interim Reporting (Topic 270) – Narrow Scope Improvements (“ASU 2025-11”), which clarifies interim disclosure requirements. ASU 2025-11 also requires entities to disclose events since the end of the last annual reporting period that have a material impact on the entity. This guidance is effective for the Company for interim reporting periods within annual reporting periods beginning on January 1, 2028. Early adoption is permitted. The guidance may be applied either (1) prospectively or (2) retrospectively to any or all prior periods presented in the financial statements. The Company does not expect the adoption of this guidance to have a material effect on its consolidated financial statements and related disclosures.

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In November 2024, the FASB issued ASU No. 2024-03 Income Statement – Reporting Comprehensive Income – Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses (“ASU 2024-03”), which requires detailed disclosures about specified categories of expenses (including employee compensation, depreciation, and amortization) included in certain expense captions presented on the face of the income statement. In January 2025, the FASB issued an update to ASU 2024-03 clarifying that all public business entities should initially adopt the disclosure requirements in the first annual reporting period beginning after December 15, 2026, and interim reporting periods beginning after December 15, 2027. ASU 2024-03 is effective for the Company for fiscal years beginning on January 1, 2027, and for interim periods beginning on January 1, 2028. Early adoption is permitted. The guidance may be applied either (1) prospectively to financial statements issued for reporting periods after the effective date of ASU 2024-03 or (2) retrospectively to all prior periods presented in the financial statements. The Company does not expect the adoption of this guidance to have a material effect on its consolidated financial statements and continues to evaluate disclosure presentation alternatives.

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Note 3. License and Collaboration Agreements

JNJ License and Collaboration Agreement

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In November 2024, the Company entered into an Amended and Restated License and Collaboration Agreement with JNJ, which amended and restated the License and Collaboration Agreement, effective July 2017, by and between the Company and JNJ, as amended in May 2019 and July 2021 (together, the “JNJ License and Collaboration Agreement”). The JNJ License and Collaboration Agreement relates to the development, manufacture and commercialization of oral IL-23R antagonist drug candidates and enables JNJ to develop collaboration compounds for multiple indications. Under the JNJ License and Collaboration Agreement, JNJ is required to use commercially reasonable efforts to develop at least one collaboration compound for at least two indications.

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During the first quarter of 2026, the Company earned a $50.0 million milestone payment upon FDA approval of ICOTYDE for the treatment of moderate-to-severe plaque psoriasis in adults and pediatric patients 12 years of age or older who weigh at least 40 kg and are candidates for systemic therapy or phototherapy. The Company has earned a total of $387.5 million in non-refundable upfront and milestone payments from JNJ under the JNJ License and Collaboration Agreement from inception in 2017 through June 30, 2026.

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Upcoming potential development milestones under the JNJ License and Collaboration Agreement include:

• $25.0 million upon the acceptance of an NDA filing by the FDA for a second indication;
• $45.0 million upon FDA approval of an NDA for a second indication;
• $35.0 million upon the acceptance of an NDA filing by the FDA for a third indication; and
• $50.0 million upon FDA approval of an NDA for a third indication.

Pursuant to the agreement, the Company is eligible to receive future sales milestone payments and tiered royalties on net product sales at percentages ranging from 6% to 10%. In addition, the Company remains eligible to receive sales milestones of up to $425.0 million.

Takeda Collaboration Agreement

In January 2024, the Company entered into a worldwide license and collaboration agreement for rusfertide with Takeda, which became effective in March 2024, and was amended in March 2025 (the “Takeda Collaboration Agreement”).

Pursuant to the Takeda Collaboration Agreement, the Company and Takeda agreed to jointly develop and commercialize rusfertide and potentially other specified second-generation injectable hepcidin mimetic compounds (the “Licensed Products”) in the United States (the “Profit-Share Territory”). Takeda was solely and exclusively responsible for the development and commercialization of the Licensed Products in all other countries (the “Takeda Territory”). The Company and Takeda shared the costs of the development, manufacture and commercialization activities for the Licensed Products in the Profit-Share Territory, provided that (i) the Company led, and was solely responsible for its costs associated with, completion of the ongoing Phase 3 VERIFY trial evaluating rusfertide for the treatment of PV; (ii) Takeda led, and was solely responsible for its costs associated with, U.S. regulatory and pre-commercialization activities related to rusfertide in the Profit-Share Territory; and (iii) Takeda led commercialization of rusfertide in the Profit-Share Territory, though the Company held an option to co-detail. Takeda was solely responsible for all costs for the development, manufacture and commercialization of the Licensed Products in the Takeda Territory. The Company granted Takeda a non-transferable, sublicensable and, except for certain specified exceptions, exclusive license to certain intellectual property of the Company to exercise its rights and perform its obligations under the Takeda Collaboration Agreement. In March 2025, the Company and Takeda agreed, pursuant to the provisions of the Takeda Collaboration Agreement, as amended, that Takeda would assume responsibility for leading and implementing the regulatory strategy and associated activities for preparation of the NDA related to rusfertide in PV, which was submitted to the FDA in December 2025. The Company was primarily responsible for clinical development activities through the NDA filing and for conducting ongoing rusfertide long-term extension studies.

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Pursuant to the Takeda Collaboration Agreement, the Company received a one-time, non-refundable upfront payment of $300.0 million in April 2024 and a $25.0 million milestone payment in September 2025.

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On April 28, 2026, the Company announced that it exercised its right to opt out of the U.S. profit and loss sharing arrangement (50% to the Company and 50% to Takeda) under the Takeda Collaboration Agreement. Following the Company’s exercise of the opt-out right, the Company has agreed to transition applicable development and commercial activities to Takeda, and Takeda has the right to assume sole operational and financial responsibility for such activities in the United States. The opt-out election triggered a $200.0 million payment, with an additional $200.0 million opt-out fee and a separate $75.0 million milestone due upon FDA approval of rusfertide. Following the opt-out, the Company is also eligible to receive up to $775.0 million in sales milestone payments and tiered royalties ranging from 14% to 29% on annual net worldwide sales, with an approximate 21% weighted-average royalty rate at $1.5 billion in annual net sales and a 29% tier applying to incremental annual net sales above $1.5 billion.

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Upcoming potential development milestones under the Takeda Collaboration Agreement include:

• $75.0 million upon FDA approval of an NDA for rusfertide in PV;
• $15.0 million upon first regulatory approval for rusfertide in PV in three European countries, after pricing and reimbursement approval; and
• $10.0 million upon first regulatory approval for rusfertide in PV in Japan.

The Company is obligated to perform certain wind-down activities during the three-month opt-out wind-down period which includes transferring the VERIFY trial and other projects to Takeda, overseeing vendors and development activities until such activities are fully transferred to Takeda, and continuing to perform the rusfertide open label extension. Such costs during the wind-down period (from April 28, 2026 to July 27, 2026) are shared (50%) with Takeda and the Company aims to transfer the majority of the activities to Takeda by July 27, 2026. As agreed upon with Takeda, Protagonist will continue work for the rusfertide open-label extension after the wind-down period until completion, which is expected in the first quarter of 2027. Costs incurred by Protagonist for any remaining wind-down activities and rusfertide open-label extension after July 27, 2026 will be fully reimbursed by Takeda.

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The Company initially evaluated the Takeda Collaboration Agreement and concluded that it had elements that were within the scope of ASC Topic 606 and ASC Topic 808. As of the effective date of the Takeda Collaboration Agreement, the Company identified two distinct performance obligations: (i) the rusfertide license delivered upon the effectiveness of the Takeda Collaboration Agreement and (ii) certain development services to be provided prior to the opt-out period, including certain of the Company’s responsibilities to complete the VERIFY Phase 3 clinical trial in PV and associated manufacturing services. Following the completion of the wind-down period on July 27, 2026, the Takeda Collaboration Agreement will no longer meet the definition of a collaborative arrangement under ASC Topic 808.

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The Company determined that the initial transaction price totaled $300.0 million, which was comprised of the upfront payment. The Company initially excluded any future estimated milestones or royalties from this transaction price, all of which were either constrained or subject to the sales-and usage-based royalty exception. As part of the Company’s evaluation of this variable consideration constraint, it determined that the potential payments were contingent upon developmental and regulatory milestones that were uncertain and were highly susceptible to factors outside of its control. The Company allocated $254.1 million of the initial transaction price to the license and $45.9 million to the development services based upon the relative standalone selling price of each performance obligation. The estimate of standalone selling price for the license was determined based on discounted cash flows for the expected development and commercialization of rusfertide and included assumptions for forecasted revenues, development timelines and expenses, discount rates, and probabilities of technical and regulatory success. The estimate of standalone selling price for the development services was determined based on forecasted costs and expenses over the expected development period. For the license of rusfertide, the Company determined that Takeda could benefit from the license at the time the license was granted and therefore, the related performance obligation was satisfied at that point in time.

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The amount allocated to the license, which represents functional intellectual property that was transferred at a point in time, was satisfied upon transfer of the license to Takeda. The amount allocated to development services will be recognized over time based on a measure of the Company’s efforts toward satisfying the performance obligation relative to the total expected efforts or inputs to satisfy the performance obligation (e.g., costs incurred compared to total budget). As of the opt-out date, the development services performance obligation remained partially unsatisfied.

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The exercise of the opt-out right results in a contract modification under ASC Topic 606 because it changes the enforceable rights and obligations of the parties under the Takeda Collaboration Agreement. As a result, the remaining unconstrained consideration was allocated to the remaining development services performance obligation, and the modification was accounted for as part of the existing contract.

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Revenue Recognition

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For the three months ended June 30, 2026, the Company recognized license and collaboration revenue of $213.5 million. This included $202.5 million under the Takeda Collaboration Agreement using the cost-based input method for development services, consisting of (i) $192.4 million related to the proportional recognition of the $200.0 million opt-out payment, (ii) $5.7 million related to cost reimbursement for post opt-out wind-down services provided by the Company, $3.4 million of which was recorded as a contract asset, and (iii) $4.4 million related to the initial upfront payment and milestones received to date. In addition, the Company recognized revenue during the period of $11.0 million for rusfertide clinical supplies under the Takeda Collaboration Agreement and other revenues. The remaining $7.6 million in revenue related to the $200.0 million opt-out payment under the Takeda Collaboration Agreement was recorded as deferred revenue on the Company’s condensed consolidated balance sheet and is expected to be recognized through the conclusion of the development services performance obligation.

For the six months ended June 30, 2026, the Company recognized license and collaboration revenue of $269.8 million. This included $205.7 million under the Takeda Collaboration Agreement using the cost-based input method for development services, consisting of (i) $192.4 million related to the proportional recognition of the $200.0 million opt-out payment, (ii) $5.7 million related to cost reimbursement for post opt-out wind-down services provided by the Company, $3.4 million of which was recorded as a contract asset, and (iii) $7.6 million related to the initial upfront payment and milestones received to date. In addition, the Company recognized a $50.0 million milestone payment related to the JNJ License and Collaboration Agreement, which was earned upon FDA approval of ICOTYDE for the treatment of moderate-to-severe plaque psoriasis, and $14.1 million for rusfertide clinical supplies under the Takeda Collaboration Agreement and other revenues.

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For the three and six months ended June 30, 2026, the Company recognized $4.4 million and $7.6 million of revenue, respectively, that was included in the deferred revenue balance at the beginning of the period. None of the costs to obtain or fulfill the contracts were capitalized.

Note 4. Fair Value Measurements

Financial assets and liabilities are recorded at fair value. The accounting guidance for fair value provides a framework for measuring fair value, clarifies the definition of fair value and expands disclosures regarding fair value measurements. Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability (an exit price) in an orderly transaction between market participants at the reporting date. The accounting guidance establishes a three-tiered hierarchy, which prioritizes the inputs used in the valuation methodologies in measuring fair value as follows:

Level 1—Inputs are unadjusted quoted prices in active markets for identical assets or liabilities at the measurement date.

*Level 2—*Inputs (other than quoted market prices included in Level 1) are either directly or indirectly observable for the asset or liability through correlation with market data at the measurement date and for the duration of the instrument’s anticipated life.

Level 3—Inputs reflect management’s best estimate of what market participants would use in pricing the asset or liability at the measurement date. Consideration is given to the risk inherent in the valuation technique and the risk inherent in the inputs to the model.

In determining fair value, the Company utilizes quoted market prices, broker or dealer quotations, or valuation techniques that maximize the use of observable inputs and minimize the use of unobservable inputs to the extent possible and considers counterparty credit risk in its assessment of fair value.

The following tables present the fair value of the Company’s financial assets determined using the inputs defined above (in thousands):

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The Company’s certificates of deposit, U.S. Treasury and agency securities, including U.S. Treasury bills, commercial paper and corporate debt securities are classified as Level 2 as they were valued based upon quoted market prices for similar instruments in active markets, quoted prices for identical or similar instruments in markets that are not active and model-based valuation techniques, for which all significant inputs are observable in the market or can be corroborated by observable market data for substantially the full term of the assets.

The carrying amount of the Company’s remaining financial assets and liabilities, including cash, receivables and payables, approximates their fair value due to their short-term nature.

Note 5. Cash Equivalents and Marketable Securities

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Cash equivalents and marketable securities consisted of the following (in thousands):

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All of the Company’s marketable securities are classified as available-for-sale. Current marketable securities of $362.5 million and $439.0 million held as of June 30, 2026 and December 31, 2025, respectively, had contractual maturities of less than one year. Noncurrent marketable securities of $66.9 million and $78.6 million held as of June 30, 2026 and December 31, 2025, respectively, had contractual maturities of at least one year but no more than two years. The Company does not intend to sell its securities that are in an unrealized loss position, and it is not more likely than not that the Company will be required to sell its securities before recovery of their amortized cost basis, which may be at maturity.

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During the six months ended June 30, 2026 and 2025, the Company sold $3.4 million and $7.0 million of marketable securities and realized a net gain of $5.0 thousand and a net loss of $5.0 thousand, respectively. The Company evaluated securities with unrealized losses to determine whether such losses, if any, were due to credit-related factors and determined that there were no credit-related losses to be recognized as of June 30, 2026 and December 31, 2025.

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Note 6. Balance Sheet Components

Prepaid Expenses and Other Current Assets

Prepaid expenses and other current assets consisted of the following (in thousands):

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Property and Equipment, Net

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Property and equipment, net consisted of the following (in thousands):

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Accrued Expenses and Other Payables

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Accrued expenses and other payables consisted of the following (in thousands):

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Note 7. Stockholders’ Equity

Pre-Funded Warrants

In August 2023, the Company entered into certain agreements with certain accredited investors and their affiliates (the “Investors”) under which the Company issued pre-funded warrants with an exercise price of $0.001 per share (the “Pre-Funded Warrants”). The Pre-Funded Warrants will expire on the day they are exercised in full. The Pre-Funded Warrants are exercisable at any time prior to expiration except that the Pre-Funded Warrants cannot be exercised by the Investors if, after giving effect thereto, the Investors would beneficially own more than 9.99% of the Company’s common stock, subject to certain exceptions. In accordance with ASC Topic 260, “Earnings Per Share”, outstanding Pre-Funded Warrants are included in the computation of basic net income (loss) per share because the exercise price is negligible, and they are fully vested and exercisable after the original issuance date. No Pre-Funded Warrants were exercised during the three and six months ended June 30, 2026 and 2025. As of June 30, 2026, Pre-Funded Warrants to purchase 1,500,000 shares of common stock remained outstanding.

Note 8. Income Taxes

The Company recorded income tax expense of $2.3 million and $0.8 million for the three and six months ended June 30, 2026, respectively. The Company recorded income tax expense of $0.2 million for both the three and six months ended June 30, 2025. The increases in income tax expense were due to pretax income recorded as compared to pretax losses for the prior year periods. The tax provision for the three and six months ended June 30, 2026 was determined using an estimated annual effective tax rate, adjusted for discrete items, if any.

Note 9. Net Income (Loss) per Share

The computation of basic net income (loss) per share of common stock is based on the weighted-average number of shares of common stock outstanding during each period. The computation of diluted net income (loss) per share of common stock is based on the weighted-average number of shares of common stock outstanding during the period plus, when their effect is dilutive, incremental shares consisting of shares subject to stock options, RSUs, PSUs, the Company’s employee stock purchase plan (“ESPP”), and warrants.

In periods when the Company has net income, the dilutive effect of all potentially outstanding shares is computed using the treasury stock method. In periods in which the Company reports a net loss, all common stock equivalents are deemed anti-dilutive such that basic net loss per share of common stock and diluted net loss per share of common stock are equal.

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The following table sets forth the computation of basic and diluted net income (loss) per share (in thousands, except share and per share data):

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Approximately 0.9 million potentially dilutive shares of common stock (consisting of shares subject to outstanding stock options, RSUs, PSUs and under the ESPP, as applicable) were excluded from the diluted net income per share of common stock computation for the three and six months ended June 30, 2026 because their effect was anti-dilutive. Approximately 9.5 million potentially dilutive shares of common stock (consisting of shares subject to outstanding stock options, RSUs, PSUs, and under the ESPP, as applicable) were excluded from the diluted net loss per share of common stock computation for the three and six months ended June 30, 2025 due to the Company’s net loss for these periods.

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Note 10. Segment Reporting

Operating segments are components of an enterprise for which separate financial information is available and which are evaluated by a company’s chief operating decision maker (“CODM”) in deciding how to allocate resources and to assess performance.

The Company operates and manages its business as one operating segment, which primarily focuses on the discovery and development of innovative medicines in areas of unmet medical need. The Company’s Chief Executive Officer serves as the Company’s CODM and manages and allocates resources to the operations of the Company on an entity-wide basis. Managing and allocating resources on an entity-wide basis enables the CODM to assess the overall level of resources available and how to best deploy these resources across functions and research and development projects based on unmet medical need, scientific data, probability of technical and regulatory successful development, market potential and other considerations, and, as necessary, reallocate resources among the Company’s internal research and development portfolio and external opportunities to best support the long-term growth of the Company’s business. The Company’s CODM reviews financial information on an aggregate basis for the purpose of allocating resources and evaluating financial performance, including segment net income (loss), which is also reported on the condensed consolidated statement of operations as consolidated net income (loss).

Segment information was as follows (in thousands):

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(1) Amounts exclude employee wages and benefits, stock-based compensation and expense allocations.

(2) As of April 1, 2025, the information regularly provided to the CODM was changed to reclassify pre-clinical expenses from development expense to discovery expense. Prior period segment information has been recast to reflect this change.

(3) Other segment items include foreign currency related income (expense) and other miscellaneous income (expense).

The accounting policies of the Company’s operating segment are the same as those described in Note 2. Summary of Significant Accounting Policies. The measure of segment assets is reported as total assets on the Company’s condensed consolidated balance sheets for the periods presented.

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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 our Unaudited Condensed Consolidated Financial Statements and related notes included in Part I, Item 1 of this Quarterly Report on Form 10-Q (the “Quarterly Report”) and with our Audited Consolidated Financial Statements and related notes thereto for the year ended December 31, 2025, included in our Annual Report on Form 10-K filed with the Securities and Exchange Commission (the “SEC”) on February 25, 2026.

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Results of Operations

Comparison of the Three Months Ended June 30, 2026 and 2025

*Percentage not meaningful.

(1) Includes $7.5 million and $6.3 million of non-cash stock-based compensation expense for the three months ended June 30, 2026 and 2025, respectively.

(2) Includes $6.5 million and $4.6 million of non-cash stock-based compensation expense for the three months ended June 30, 2026 and 2025, respectively.

License and Collaboration Revenue

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License and collaboration revenue was comprised of the following for the periods presented:

*Percentage not meaningful.

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Our revenue is derived from licensing and collaboration agreements and is highly variable and dependent upon factors such as the timing of when regulatory and sales milestones are achieved, if at all, commercial launch efforts by our collaboration partners, and the accounting for any upfront payments associated with any existing or new agreements.

​

License and collaboration revenue for the three months ended June 30, 2026, was $213.5 million, which consisted of (i) $192.4 million related to the proportional recognition of the $200.0 million opt-out payment received from Takeda, and (ii) $21.1 million for ongoing development services, including post opt-out wind down services, rusfertide clinical supplies provided by us under the Takeda Collaboration Agreement and other revenues.

​

License and collaboration revenue for the three months ended June 30, 2025 was $5.5 million, which consisted of (i) $5.0 million for development services provided by us during the period under the Takeda Collaboration Agreement based on the cost-based input method and (ii) $0.5 million related to the proportional recognition of the $25.0 million milestone from Takeda deemed probable of being achieved due to the Phase 3 VERIFY trial meeting its primary endpoint.

​

As described above, we opted out of the U.S. profit and loss sharing arrangement under the Takeda Collaboration Agreement in April 2026 and are eligible to receive both an additional $200.0 million opt-out payment and an enhanced milestone payment of $75.0 million upon FDA approval of rusfertide, which is expected in August 2026. In addition, we may receive royalties and sales milestones from rusfertide, pending potential FDA approval and commercial launch.

​

Research and Development Expenses

*Percentage not meaningful.

​

Research and development expenses increased $5.0 million, or 14%, from $37.0 million for the three months ended June 30, 2025 to $42.1 million for the three months ended June 30, 2026. The increase was primarily due to an increase of $8.6 million in costs related to our Phase 1 study for development candidate PN-881 initiated in the third quarter of 2025 and an $8.4 million increase in pre-clinical and drug discovery research program expense, partially offset by a decrease of $12.0 million in rusfertide expenses primarily related to the completion of our Phase 3 VERIFY trial during the first quarter of 2025.

​

We had 108 and 100 full-time equivalent research and development headcount as of June 30, 2026 and 2025, respectively. Research and development personnel-related expenses for the three months ended June 30, 2026 increased by $1.9 million as compared to the three months ended June 30, 2025, primarily driven by increases in wages, benefits and stock-based compensation.

​

We expect research and development expenses to increase significantly in the second half of 2026 compared to the first half of 2026. The increase is expected to be driven primarily by the advancement of PN-881 into a comprehensive Phase 2b psoriasis program, planned investments in clinical manufacturing and related activities, including at-risk expenditures to ensure readiness for other programs as they advance to clinical development (PN-477sc, PN-458, PN-8047), additional pre-clinical discovery programs, and increases in headcount and stock-based compensation expense. The timing and magnitude of these expenses will vary depending on the progress of our programs, including the initiation and pace of clinical trials and related development activities.

​

General and Administrative Expenses

​

General and administrative expenses increased $2.1 million, or 20%, from $10.6 million for the three months ended June 30, 2025 to $12.6 million for the three months ended June 30, 2026. The increase was primarily due to an increase in personnel-related expenses driven by increases in wages, benefits and stock-based compensation.

​

We had 33 and 30 full-time equivalent general and administrative headcount as of June 30, 2026 and 2025, respectively.

​

Interest Income

​

Interest income decreased by $1.0 million, or 13%, from $7.4 million for the three months ended June 30, 2025 to $6.4 million for the three months ended June 30, 2026 primarily due to lower yields and lower average investment balance as compared to the prior period.

​

Income Tax Expense

Income tax expense was $2.3 million and $0.2 million for the three months ended June 30, 2026 and 2025, respectively. The increase in income tax expense for the three months ended June 30, 2026 was primarily due to pretax income recorded as compared to a pretax loss for the prior year period. The effective tax rate was 1.4% and 0% for the three months ended June 30, 2026 and 2025, respectively.

​

Comparison of the Six Months Ended June 30, 2026 and 2025

*Percentage not meaningful.

​

(1) Includes $15.3 million and $14.3 million of non-cash stock-based compensation expense for the six months ended June 30, 2026 and 2025, respectively.

(2) Includes $13.2 million and $10.4 million of non-cash stock-based compensation expense for the six months ended June 30, 2026 and 2025, respectively.

License and Collaboration Revenue

​

License and collaboration revenue was comprised of the following for the periods presented:

*Percentage not meaningful.

​

Our revenue is derived from licensing and collaboration agreements and is highly variable and dependent upon factors such as the timing of when regulatory and sales milestones are achieved, if at all, commercial launch efforts by our collaboration partners, and the accounting for any upfront payments associated with any existing or new agreements.

​

License and collaboration revenue for the six months ended June 30, 2026 was $269.8 million, which consisted of (i) $192.4 million related to the proportional recognition of the $200.0 million opt-out payment received under the Takeda Collaboration Agreement, (ii) $27.4 million for ongoing development services, including post opt-out wind down services, rusfertide clinical supplies provided by us under the Takeda Collaboration Agreement and other revenues, and (iii) a $50.0 million milestone payment related to the JNJ License and Collaboration Agreement, which was earned upon FDA approval of ICOTYDE for the treatment of moderate-to-severe plaque psoriasis.

​

License and collaboration revenue for the six months ended June 30, 2025 was $33.9 million, which consisted of (i) $23.4 million related to the proportional recognition of the $25.0 million milestone from Takeda deemed probable of being achieved due to the Phase 3 VERIFY trial meeting its primary endpoint and (ii) $10.5 million for development

services provided by us during the period under the Takeda Collaboration Agreement based on the cost-based input method.

​

Research and Development Expenses

*Percentage not meaningful.

Research and development expenses increased $15.9 million, or 22%, from $72.9 million for the six months ended June 30, 2025 to $88.8 million for the six months ended June 30, 2026. The increase was primarily due to an increase of $17.4 million in costs related to our Phase 1 study for development candidate PN-881 initiated in the third quarter of 2025 and a $14.4 million increase in pre-clinical and drug discovery research program expense, partially offset by a decrease of $15.9 million in rusfertide expenses primarily related to the completion of our Phase 3 VERIFY trial during the first quarter of 2025.

​

We had 108 and 100 full-time equivalent research and development headcount as of June 30, 2026 and 2025, respectively. Research and development personnel-related expenses for the six months ended June 30, 2026 increased by $2.9 million as compared to the six months ended June 30, 2025, primarily driven by increases in wages, benefits and stock-based compensation.

​

We expect research and development expenses to increase significantly in the second half of 2026 compared to the first half of 2026. The increase is expected to be driven primarily by the advancement of PN-881 into a comprehensive Phase 2b psoriasis program, planned investments in clinical manufacturing and related activities, including at-risk expenditures to ensure readiness for other programs as they advance to clinical development (PN-477sc, PN-458, PN-8047), additional pre-clinical discovery programs, and increases in headcount and stock-based compensation expense. The timing and magnitude of these expenses will vary depending on the progress of our programs, including the initiation and pace of clinical trials and related development activities.

​

General and Administrative Expenses

General and administrative expenses increased $3.6 million, or 16%, from $22.3 million for the six months ended June 30, 2025 to $25.9 million for the six months ended June 30, 2026. The increase was primarily due to an increase in personnel-related expenses, primarily driven by increases in wages, benefits and stock-based compensation.

​

We had 33 and 30 full-time equivalent general and administrative headcount as of June 30, 2026 and 2025, respectively.

​

Interest Income

​

Interest income decreased by $2.7 million, or 18%, from $15.0 million for the six months ended June 30, 2025 to $12.3 million for the six months ended June 30, 2026 primarily due to lower yields and lower average investment balance as compared to the prior period.

​

Income Tax Expense

Income tax expense was $0.8 million and $0.2 million for the six months ended June 30, 2026 and 2025, respectively. The increase in income tax expense for the six months ended June 30, 2026 was primarily due to pretax income recorded as compared to a pretax loss for the prior year period. The effective tax rate was 0.5% and 0% for the six months ended June 30, 2026 and 2025, respectively.

​

Liquidity and Capital Resources

​

Sources of Liquidity

​

We had $849.5 million and $646.0 million in cash, cash equivalents and marketable securities as of June 30, 2026 and December 31, 2025, respectively. Historically, we have funded our operations primarily from receipt of payments under collaboration agreements, as discussed in “Collaboration Agreements” above, and net proceeds from the sale of shares of our common stock.

Capital Requirements

​

As of June 30, 2026, we had $849.5 million in cash, cash equivalents and marketable securities and an accumulated deficit of $304.0 million. Our capital expenditures were $0.4 million and $1.6 million for the six months ended June 30, 2026 and the year ended December 31, 2025, respectively. Our primary uses of cash are to fund our operating expenses, including our research and development expenditures and general and administrative costs. We expect that our existing cash, cash equivalents and marketable securities will be sufficient to fund our operations for at least the next twelve months from the date of this Quarterly Report based on current operating plans and financial forecasts.

​

We do not currently anticipate a need for additional funding in the near term. However, we may require additional funding in the future to advance our discovery pipeline and to develop, acquire, or in-license other potential product candidates. Our future funding requirements will depend on many factors, including those described in Part II, Item 1A, “Risk Factors” herein and in Part 1, Item 1A, “Risk Factors” in our Annual Report on Form 10-K for the year ended December 31, 2025. Such additional funding may come from various sources, including raising additional capital, seeking access to debt, and seeking additional collaborative or other arrangements with partners, but such funding may not be available on terms acceptable to us, if at all.

Cash Flows

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

Cash Provided by Operating Activities

Cash provided by operating activities for the six months ended June 30, 2026 was $170.1 million and consisted primarily of net income of $166.6 million and certain non-cash items, including $28.6 million of stock-based compensation expense, partially offset by a net change of $24.7 million in net operating assets and liabilities. The $73.5 million increase in cash provided by operating activities during the six months ended June 30, 2026, as compared

to the six months ended June 30, 2025, was primarily due to a $200.0 million payment received upon the exercise of our opt-out right under the Takeda Collaboration Agreement in April 2026 and a $50.0 million milestone payment received under the JNJ License and Collaboration Agreement, partially offset by a $178.3 million change in receivable from collaboration partner during the six months ended June 30, 2026.

Cash Provided by (Used in) Investing Activities

Cash provided by investing activities for the six months ended June 30, 2026 was $88.5 million and consisted primarily of proceeds from maturities and sales of marketable securities of $292.5 million, partially offset by purchases of marketable securities of $203.6 million and purchases of property and equipment of $0.4 million. The $128.1 million increase in cash provided by investing activities for the six months ended June 30, 2026, as compared to the six months ended June 30, 2025, was primarily related to the investment of payments received from collaboration partners in 2026. Purchases of property and equipment were primarily related to laboratory equipment and furniture and fixtures.

Cash Provided by Financing Activities

Cash provided by financing activities for the six months ended June 30, 2026 was $33.1 million and consisted of net cash proceeds from the issuance of common stock upon exercises of stock options and purchases of stock under our employee stock purchase plan (“ESPP”). The $18.7 million increase in cash provided by financing activities for the six months ended June 30, 2026, as compared to the six months ended June 30, 2025, was primarily due to an $18.3 million increase in proceeds from the issuance of common stock upon exercise of options and purchases of common stock under the ESPP.

Contractual Obligations and Other Commitments

During the six months ended June 30, 2026, there were no material changes to our material cash requirements, including commitments for capital expenditures, described under Management’s Discussion and Analysis of Financial Condition and Results of Operations in our Annual Report on Form 10-K for the year ended December 31, 2025 filed with the SEC on February 25, 2026.

​

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 related to our interest-earning investments and inflation risk affecting labor costs and clinical trial costs.

Interest Rate Fluctuation Risk

We had $849.5 million and $646.0 million in cash, cash equivalents and marketable securities at June 30, 2026 and December 31, 2025, respectively. Our cash and cash equivalents consist of cash, money market funds, certificates of deposit and commercial paper. Marketable securities consist of government and agency bonds, commercial paper and corporate bonds. A portion of our investments may be subject to interest rate risk and could decline in value if market interest rates increase. Based on our interest rate sensitivity analysis, an immediate 100 basis point increase in interest rates would increase our annual interest income by approximately $5.4 million, while an immediate 100 basis point decrease in interest rates would decrease our annual interest income by approximately $5.4 million.

Approximately $2.5 million and $2.8 million of our cash balance was located in Australia at June 30, 2026 and December 31, 2025, respectively. Our expenses, except those related to our Australian operations, are generally denominated in U.S. dollars. For our operations in Australia, the majority of our expenses are denominated in Australian dollars. To date, we have not had a formal hedging program with respect to foreign currency, but we may do so in the future if our exposure to foreign currency becomes more significant. A 10% increase or decrease in current exchange rates would not have a material effect on the results of our operations.

Inflation Fluctuation Risk

Inflation generally affects us by increasing our costs, such as the cost of labor and research and development contract costs. We do not believe inflation has had a material adverse effect on the results of our operations during the six months ended June 30, 2026.

ITEM 4.CONTROLS AND PROCEDURES

Evaluation of Disclosure Controls and Procedures

Management, under the supervision and with the participation of our Chief Executive Officer (Principal Executive Officer) and Chief Financial Officer (Principal Financial Officer), has evaluated the effectiveness of our disclosure controls and procedures (as defined in Rules 13a-15(e) and 15d-15(e) under the Exchange Act) as of the end of the period covered by this report. Based on the evaluation of our disclosure controls and procedures, our Chief Executive Officer and Chief Financial Officer have concluded that, as of the end of the period covered by this report, our disclosure controls and procedures were effective at the reasonable assurance level.

Limitations on Effectiveness of Controls and Procedures and Internal Control over Financial Reporting

​

In designing and evaluating the disclosure controls and procedures and internal control over financial reporting, management recognizes that any controls and procedures, no matter how well designed and operated, can provide only reasonable assurance of achieving the desired control objectives. In addition, the design of disclosure controls and procedures and internal control over financial reporting must reflect the fact that there are resource constraints, and that management is required to apply judgment in evaluating the benefits of possible controls and procedures relative to their costs.

Changes in Internal Control over Financial Reporting

There have been no changes in our internal control over financial reporting that occurred during the most recent fiscal quarter that have materially affected, or are reasonably likely to materially affect, our internal control over financial reporting.

PART II – OTHER INFORMATION

​

ITEM 1.LEGAL PROCEEDINGS

​

From time to time, we may become subject to litigation and claims arising in the ordinary course of business. We are not currently a party to any material legal proceedings, and we are not aware of any pending or threatened legal proceeding against us that we believe could have a material adverse effect on our business, operating results, financial condition or cash flows.

ITEM 1A.RISK FACTORS

Our business, results of operations and financial condition are subject to various risks. These risks are described elsewhere in this Quarterly Report on Form 10-Q and in our other filings with the SEC, including our Annual Report on Form 10-K for the year ended December 31, 2025. Except as disclosed below, there have been no material changes from the risk factors identified in the Company’s Annual Report on Form 10-K for the year ended December 31, 2025.

We are dependent on Takeda for the commercialization of rusfertide. Failure by Takeda to commercialize rusfertide could result in a material adverse effect on our business and operating results.

Pursuant to the terms of the Takeda Collaboration Agreement, following our exercise of our right to opt out of the U.S. profit and loss sharing arrangement in April 2026, Takeda has an exclusive worldwide license to develop and commercialize rusfertide, and we are eligible to receive tiered royalties ranging from 14% to 29% on annual worldwide

net sales, with an approximate weighted-average royalty rate of 21% at $1.5 billion in annual net sales and a rate of 29% for incremental annual net sales over $1.5 billion. In addition, under the agreement, we are eligible to receive up to $775.0 million in sales milestone payments.

A substantial portion of our total revenue may be based on royalties and milestones received from Takeda. The commercial success of rusfertide, if approved, including our potential royalties, depends on, among other things, the efforts and allocation of resources of Takeda, which we do not control. Our partnership with Takeda may not be successful, and we may not realize the expected benefits from such partnership, due to a number of important factors, including but not limited to the following:

• Takeda may change the focus of its commercialization efforts or pursue higher priority programs;
• Takeda may fail to manufacture or supply sufficient drug product of rusfertide in compliance with applicable laws and regulations, which could result in program delays or lost revenue; and
• We may disagree with Takeda regarding the development or commercialization of rusfertide, or other matters under the Takeda Collaboration Agreement, or Takeda could breach or terminate the Takeda Collaboration Agreement.

Unstable market and macroeconomic conditions, including geopolitical instability and tariffs or trade policy, may have serious adverse consequences on our business, financial condition and stock price.

As has been widely reported, we are currently operating in a period of macroeconomic uncertainty and capital markets disruption, which has been significantly impacted by domestic and global monetary and fiscal policy, trade regulations, including changes in trade policies, tariffs or other trade restrictions or the threat of such actions, geopolitical instability, including ongoing military conflicts in the Middle East and between Russia and Ukraine, rising tensions between China and Taiwan, and high interest rates. In particular, the conflicts in the Middle East and Ukraine have exacerbated market disruptions, including significant volatility in commodity prices, as well as supply chain interruptions, and have contributed to inflation globally. The U.S. Federal Reserve and other central banks may be unable to contain inflation through more restrictive monetary policy and inflation may increase or continue for a prolonged period of time. Inflationary factors, such as increases in the cost of clinical supplies, interest rates, overhead costs and transportation costs may adversely affect our operating results. In addition, in September 2025, the United States announced the imposition of up to 100% tariffs on imported branded or patented pharmaceuticals, subject to certain exceptions. In early April 2026, the current administration issued a proclamation under Section 232 of the Trade Expansion Act of 1962 determining that imports of certain pharmaceutical products, including patented pharmaceuticals, associated active pharmaceutical ingredients and related materials could threaten U.S. national security and authorized the imposition of tariffs of up to 100% on covered imports, effective July 31, 2026. Imports of certain listed products from specific partner countries, including South Korea and the European Union, may be subject to reduced tariff rates. Certain tariff exemptions or zero-rate treatment may be available for products where all approved indications are designated as orphan, subject to applicable determinations, conditions and implementation guidance. There remains substantial uncertainty as to whether such tariffs would apply to the importation of active pharmaceutical ingredients or bulk drug products that are intended for use in clinical trials and, more generally, about the duration of existing tariffs, tariff levels, implementation of announced tariffs, litigation challenging tariffs and whether additional tariffs or retaliatory actions may be imposed, modified or suspended. Although we do not believe that the macroeconomic factors discussed above have had a material impact on our financial position or results of operations to date, our financial position or results of operations may be adversely affected in the future due to these factors, and such factors may lead to increases in the cost of manufacturing our product candidates and delays in initiating trials. In addition, global credit and financial markets have experienced extreme volatility and disruption in the past several years and the foregoing factors have led to and may continue to cause diminished liquidity and credit availability, declines in consumer confidence, declines in economic growth, uncertainty about economic stability and continued inflation.

There can be no assurance that further deterioration in credit and financial markets and confidence in economic conditions will not occur. A future recession or market correction or other significant geopolitical events could materially affect our business and the value of our common stock. Our general business strategy may be adversely

affected by any such economic downturn, volatile business environment or continued unpredictable and unstable market conditions. If the current equity and credit markets deteriorate, or do not improve, it may make any necessary debt or equity financing more difficult, more costly, and more dilutive. Failure to secure any necessary financing in a timely manner and on favorable terms could have a material adverse effect on our growth strategy, financial performance and stock price and could require us to delay or abandon clinical development plans. In addition, there is a risk that one or more of our current service providers, manufacturers and other partners may not survive these difficult economic times, which could directly affect our ability to attain our operating goals.

ITEM 2.UNREGISTERED SALES OF EQUITY SECURITIES AND USE OF PROCEEDS

Recent Sales of Unregistered Securities

None.

Repurchases of Shares or of Company Equity Securities

None.

ITEM 3.DEFAULTS UPON SENIOR SECURITIES

None.

ITEM 4.MINE SAFETY DISCLOSURES

Not applicable.

ITEM 5.OTHER INFORMATION

(c) Trading Plans

​

On June 30, 2026, Asif Ali, our Chief Financial Officer, adopted a trading plan intended to satisfy Rule 10b5-1(c) to sell up to (i) 73,214 shares of the Company’s common stock, (ii) 50% of the net shares issued to Mr. Ali after withholding taxes upon the vesting of restricted stock unit awards representing 21,346 shares of the Company’s common stock, and (iii) 50% of the net shares issued to Mr. Ali after withholding taxes upon the vesting of performance stock unit awards representing 12,800 shares of the Company’s common stock (assuming that such shares underlying performance stock units vest at target amounts) through September 30, 2027, or such earlier date when all transactions under the trading plan are completed, subject to certain conditions.

​

Except as discussed above, during the fiscal quarter ended June 30, 2026, no director or Section 16 officer adopted or terminated any Rule 10b5-1 trading arrangement or a non-Rule 10b5-1 trading arrangement (in each case as defined in Item 408(a) of Regulation S-K).

​

​

ITEM 6.EXHIBITS

​

EXHIBIT INDEX

​

• Filed herewith.

• This certification attached as Exhibit 32.1 that accompanies this Quarterly Report on Form 10-Q is not deemed filed with the Securities and Exchange Commission and is not to be incorporated by reference into any filing of Protagonist Therapeutics, Inc. under the Securities Act of 1933, as amended, or the Securities Exchange Act of 1934, as amended, whether made before or after the date of the Form 10-Q, irrespective of any general incorporation language contained in such filing.

​

​ ​ ​

​ ​ ​

Date: August 5, 2026 By: /s/ Dinesh V. Patel, Ph.D.

​ ​ Dinesh V. Patel, Ph.D.

​ ​ President, Chief Executive Officer and Director

​ ​ (Principal Executive Officer)

​ ​ ​

Date: August 5, 2026 By: /s/ Asif Ali

​ ​ Asif Ali

​ ​ Executive Vice President, Chief Financial Officer

​ ​ (Principal Financial and Accounting Officer)

​

​

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