4. Royalty and Commercial Payment Purchase Agreements

The Company recognizes receivables from RPAs under two methods, the cost recovery method and the EIR method.

The following table summarizes the royalty and commercial payment receivable activities under the cost recovery method during the three months ended March 31, 2026 (in thousands):

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The following table summarizes the royalty and commercial payment receivable activities under the cost recovery method during the three months ended March 31, 2025 (in thousands):

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The following table summarizes the royalty and commercial payment receivable activities under the EIR method during the three months ended March 31, 2026 (in thousands):

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The following table summarizes the royalty and commercial payment receivable activities under the EIR method during three months ended March 31, 2025 (in thousands):

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The following table summarizes income recognized from purchased receivables under the EIR method and cost recovery method during the three months ended March 31, 2026 and 2025 (in thousands):

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Fully Recovered Royalty and Commercial Payment Purchase Agreements Under the Cost Recovery Method

Viracta Royalty Purchase Agreement

In March 2021, the Company entered into the Viracta RPA, as amended in March 2024, pursuant to which the Company acquired the right to receive future royalties, milestone payments, and other payments related to two clinical-stage drug candidates for an upfront payment of $13.5 million. The first candidate, tovorafenib (DAY101) (the first and only type II RAF inhibitor now marketed as OJEMDA), is developed by Day One, and the second candidate, vosaroxin (a topoisomerase II inhibitor), is being developed by Denovo Biopharma LLC. The Company acquired the right to receive (i) up to $54.0 million in potential milestone payments, potential royalties on sales, if approved, and a portion of potential other payments related to DAY101, excluding up to $5.0 million retained by Viracta, and (ii) up to $57.0 million in potential regulatory and commercial milestones and high single-digit royalties on sales related to vosaroxin, if approved. In December 2024, the Company entered into the Viracta Assignment Agreements with Viracta through which the Company became the patent holder of the IP and know-how related to OJEMDA that was out-licensed to Day One and where Viracta assigned to the Company all its rights, title, and interest in the Day One License Agreement. The Company did not acquire new rights to additional milestone and royalty payments as a result of the execution of the Viracta Assignment Agreements that were not acquired under the Viracta RPA. On April 23, 2026, Servier completed its acquisition of Day One.

As of March 31, 2026 and December 31, 2025, there was $2.8 million and $2.6 million in trade and other receivables, net related to this agreement, respectively. The Company recognized $2.8 million in income from purchased receivables under the cost recovery method related to this agreement during the three months ended March 31, 2026. The Company recognized $5.5 million in income from purchased receivables under the cost recovery method related to this arrangement during the three months ended March 31, 2025, which included a $4.0 million milestone related to Day One’s MAA filing with the EMA and $1.5 million in estimated royalties.

Royalty and Commercial Payment Purchase Agreements Under the EIR Method

Short-term royalty and commercial payment receivables under the EIR method were $18.7 million and $22.8 million as of March 31, 2026 and December 31, 2025, respectively. Long-term royalty and commercial payment receivables under the EIR method were $4.2 million and $4.4 million as of March 31, 2026 and December 31, 2025, respectively.

Affitech Commercial Payment Purchase Agreement

In October 2021, the Company entered into the Affitech CPPA, pursuant to which, the Company purchased a future stream of commercial payment rights to Roche’s faricimab from Affitech for an upfront payment of $6.0 million. The Company is eligible to receive 0.5% of future net sales of faricimab for a ten-year period following the first commercial sales in each applicable jurisdiction.

In January 2022, Roche received approval from the FDA to commercialize VABYSMO (faricimab-svoa) for the treatment of wet, or neovascular, age-related macular degeneration and diabetic macular edema. In September 2022, Roche received approval from the European Commission to commercialize VABYSMO for the treatment of wet, or neovascular, age-related macular degeneration and visual impairment due to diabetic macular edema. Commercial payments are due from Roche to the Company within 60 days of December 31 and June 30 of each year.

In March 2025, the Company paid $6.0 million to Affitech, which included $3.0 million for the third sales milestone liability that was recorded in the first quarter of 2024 and an additional $3.0 million for the fourth sales milestone. With this payment, all milestone payments to Affitech under the Affitech CPPA have been fully paid.

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The Company recognized $6.7 million and $5.8 million in income from purchased receivables under the EIR method during the three months ended March 31, 2026 and 2025, respectively.

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During the three months ended March 31, 2026 and 2025, the Company received commercial payments pursuant to the Affitech CPPA of $11.9 million and $11.1 million, respectively.

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No allowance for credit losses was recorded as of March 31, 2026 and December 31, 2025.

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Aptevo Commercial Payment Purchase Agreement

In March 2023, the Company entered into the Aptevo CPPA, pursuant to which the Company acquired from Aptevo a portion of its milestone and commercial payment rights under a sale agreement dated February 28, 2020 between Aptevo and Medexus, related to IXINITY, which is marketed by Medexus for the control and prevention of bleeding episodes and postoperative management in people with Hemophilia B.

The Company is eligible to receive a mid-single digit percentage of all IXINITY quarterly net sales from January 1, 2023 until the first quarter of 2035, and will be entitled to milestone payments of up to $5.3 million.

The Company recognized $0.2 million and $0.3 million in income from purchased receivables under the EIR method during the three months ended March 31, 2026 and 2025, respectively. During the three months ended March 31, 2026 and 2025, the Company received commercial payments pursuant to the Aptevo CPPA of $0.5 million and $0.6 million, respectively.

No allowance for credit losses was recorded as of March 31, 2026 and December 31, 2025.

LadRx Agreements

In June 2023, the Company entered into the LadRx AAA pursuant to which the Company acquired from LadRx all of its rights, title, and interest related to MIPLYFFA under the Zevra APA between Zevra and LadRx. The Company also entered into the LadRx RPA, pursuant to which the Company acquired the right to receive all of the future royalties, regulatory, and commercial milestone payments as well as other related payments due to LadRx from ImmunityBio related to aldoxorubicin under the ImmunityBio License Agreement between ImmunityBio and LadRx.

In June 2024, the ImmunityBio License Agreement was terminated and the Company entered into an amendment to the LadRx RPA. Under the LadRx RPA, as amended, the Company is eligible to receive potential low single-digit percentage royalty payments on aggregate net sales of aldoxorubicin. If LadRx licenses aldoxorubicin to an applicable third party, the Company is eligible to receive potential high single-digit percentage royalty payments on aggregate net sales of aldoxorubicin and a portion of any potential future milestone payments.

Historically, the Company was unable to reliably estimate its commercial payment stream from future net sales and the related commercial payments to be received under the LadRx Agreements. However, during the fourth quarter of 2025, Zevra’s periodically reported MIPLYFFA sales data, available third-party sales projections, and the Company’s history of receipts of commercial payments related to MIPLYFFA provided the Company with a greater ability to estimate future net sales and the commercial payments to be received under the LadRx AAA.

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As of October 1, 2025, when the Company assessed it was able to reliably estimate cash flows, the Company reclassified $2.9 million of royalty and commercial payment receivables under the cost recovery method to royalty and commercial payment receivables under the EIR method. The Company recognized $2.3 million in income from purchased receivables under the EIR method during the three months ended March 31, 2026.

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During the three months ended March 31, 2026, the Company received commercial payments pursuant to the LadRx Agreements of $1.1 million.

No allowance for credit losses was recorded as of March 31, 2026 and December 31, 2025.

Royalty and Commercial Payment Purchase Agreements Under the Cost Recovery Method

Short-term royalty and commercial payment receivables under the cost recovery method were zero as of March 31, 2026 and December 31, 2025. Long-term royalty and commercial payment receivables under the cost recovery method were $55.9 million as of March 31, 2026 and December 31, 2025.

Castle Creek Royalty Financing

In February 2025, the Company entered into a royalty financing transaction with Castle Creek, pursuant to which the Company acquired the rights to receive (a) 6.7% of the greater of (i) 8.75% of net sales in the United States or (ii) 8.00% of worldwide net sales of D-Fi (dabocemagene autoficel, also known as FCX-007), and (b) 6.7% of 20% of proceeds from a potential Priority Review Voucher if Castle Creek obtains and sells a PRV. The Company also received warrants to purchase 10,464 shares of Castle Creek's Series D-1 Preferred Stock at an exercise price of $215.03 per share, exercisable for a ten-year period expiring on February 24, 2035.

Upon the closing of the transaction, the Company paid Castle Creek an upfront payment of $5.0 million and recorded $4.4 million as long-term royalty and commercial payment receivables in its condensed consolidated balance sheet. The Company concluded that the Castle Creek PRV Interest met the definition of a derivative under ASC 815 and should be accounted for at fair value and recorded as a current liability at the inception of the transaction. The fair value of the Castle Creek PRV Interest was determined to have nominal value prior to FDA approval of D-Fi. The Company also concluded that the warrants met the definition of a derivative under ASC 815 and should be accounted for at fair value. As of March 31, 2026, the fair value of the warrants was estimated to be $0.7 million using a Black-Scholes Model with a volatility of 126.6% and risk-free rate of 3.88%. The warrants have an expected term of 4.25 years and an underlying share price of $215.03.

As of March 31, 2026, no payments were probable to be received under the Castle Creek royalty financing in the near term. Under the cost recovery method, the Company does not expect to recognize any income related to royalties, milestone payments, and other payments until the purchase price has been fully collected. No allowance for credit losses was recorded as of March 31, 2026.

Kuros Royalty Purchase Agreement

In July 2021, the Company entered into the Kuros RPA, pursuant to which the Company acquired the rights to 100% of the potential future royalties from commercial sales, which are tiered from high-single-digit to low-double-digits, and up to $25.5 million in pre-commercial milestone payments associated with an existing license agreement related to Checkmate Pharmaceuticals’ vidutolimod (CMP-001), a Toll-like receptor 9 agonist, packaged in a virus-like particle, for an upfront payment of $7.0 million. The Company may pay up to an additional $142.5 million to Kuros in sales-based milestone payments.

At the inception of the Kuros RPA, the Company recorded $7.0 million as long-term royalty and commercial payment receivables under the cost recovery method in its consolidated balance sheet.

In May 2022, Regeneron completed its acquisition of Checkmate Pharmaceuticals, Inc. resulting in a $5.0 million milestone payment to Kuros. Pursuant to the Kuros RPA, the Company is entitled to 50% of the milestone payment, which was received by XOMA in July 2022. In accordance with the cost recovery method, the $2.5 million milestone received was recorded as a direct reduction of the recorded long-term royalty receivables balance.

As of March 31, 2026, no payments were probable to be received under the Kuros RPA in the near term. Under the cost recovery method, the Company does not expect to recognize any income related to royalties, milestone payments, and other payments until the purchase price has been fully collected. No allowance for credit losses was recorded as of March 31, 2026 and December 31, 2025.

Palobiofarma Royalty Purchase Agreement

In September 2019, the Company entered into the Palo RPA, pursuant to which the Company acquired the rights to potential royalty payments in low single-digit percentages of aggregate net sales associated with six product candidates in various clinical development stages, targeting the adenosine pathway with potential applications in solid tumors, non-Hodgkin’s lymphoma, asthma/chronic obstructive pulmonary disease, ulcerative colitis, idiopathic pulmonary fibrosis, lung cancer, psoriasis, and nonalcoholic steatohepatitis and other indications that are being developed by Palo.

Under the terms of the Palo RPA, the Company paid Palo an upfront payment of $10.0 million payment at the close of the transaction, which occurred simultaneously upon parties’ entry into the Palo RPA in September 2019. At the inception of the agreement, the Company recorded $10.0 million as long-term royalty and commercial payment receivables under the cost recovery method in its consolidated balance sheet.

As of March 31, 2026, no payments were probable to be received under the Palo RPA in the near term. Under the cost recovery method, the Company does not expect to recognize any income related to royalties received until the purchase price has been fully collected. No allowance for credit losses was recorded as of March 31, 2026 and December 31, 2025.

Twist Bioscience Royalty Purchase Agreement

In October 2024, the Company entered into the Twist RPA. Under the terms of the Twist RPA, the Company acquired 50% of certain contingent payments (including royalties, milestone payments, sublicense income, and option exercise payments) related to Twist’s 60-plus early-stage programs across over 30 partners for a $15.0 million upfront payment. The Company is eligible to receive up to $0.5 billion in milestone payments and a 50% share of up to low-single-digit royalties on future commercial sales.

Upon closing of the transaction, the Company paid Twist an upfront payment of $15.0 million which was recorded as long-term royalty and commercial payment receivables under the cost recovery method in its consolidated balance sheet.

Given the limited available information and early stage of the programs, the Company was unable to reasonably estimate future milestone payments or net sales and the royalty payments to be received over the twelve-month period following the condensed consolidated balance sheet date of March 31, 2026 and, as such, no amounts were reflected as short-term royalty and commercial payment receivables under the cost recovery method as of March 31, 2026.

As of March 31, 2026, no payments were probable to be received under Twist RPA in the near term. Under the cost recovery method, the Company does not expect to recognize any income related to royalties, milestone payments and other payments until the purchase price has been fully collected. No allowance for credit losses was recorded as of March 31, 2026 and December 31, 2025.

Daré Royalty Purchase Agreements

In April 2024, the Company entered into the Daré RPAs. Pursuant to the terms of the Daré RPAs, the Company paid $22.0 million in cash to Daré in consideration for the sale of (a) 100% of all remaining royalties related to XACIATO not already subject to the royalty-backed financing agreement Daré entered into in December 2023 and net of payments owed by Daré to upstream licensors, which equates to royalties ranging from low to high single digits, and all potential commercial milestones related to XACIATO that are payable to Daré under the Daré Organon License Agreement; and (b) a 4% synthetic royalty on net sales of OVAPRENE and a 2% synthetic royalty on net sales of DARE to PLAY^TM (Sildenafil Cream), which will decrease to 2.5% and 1.25%, respectively, upon the Company achieving a pre-specified return threshold. The Daré RPAs also provide for milestone payments to Daré of $11.0 million for each successive $22.0 million received by the Company under the Daré RPAs after achievement of a return threshold of $88.0 million.

Upon closing of the transaction, the Company paid Daré an upfront payment of $22.0 million which was recorded as long-term royalty and commercial payment receivables in the condensed consolidated balance sheet. The Company concluded that the milestone payments to Daré did not meet the definition of a derivative under ASC 815 and expects to recognize the milestone payments as liabilities when probable and reasonably estimable.

Given the limited available information, the Company was unable to reasonably estimate future net sales and the commercial payments to be received over the twelve-month period following the condensed consolidated balance sheet date of March 31, 2026 and, as such, no amounts were reflected as short-term royalty and commercial payment receivables as of March 31, 2026.

During the three months ended March 31, 2026, the Company received de minimis commercial payments pursuant to the Daré RPAs. In accordance with the cost recovery method, the cash received was recorded as a direct reduction of the long-term royalty and commercial payment receivables under the cost recovery method.

Under the cost recovery method, the Company does not expect to recognize any income related to milestones and commercial payments received until the purchase price has been fully collected. No allowance for credit losses was recorded as of March 31, 2026 and December 31, 2025.