On November 4, 2024, the Company entered into a Purchase and Sale Agreement, or the Purchase and Sale Agreement, with Royalty Pharma Development Funding, LLC, or Royalty Pharma, pursuant to which Royalty Pharma purchased rights to certain revenue streams from net sales of products comprising or containing axatilimab (including Niktimvo™) by the Company, its affiliates and its licensees in the United States and its respective territories, districts, commonwealths and possessions (including Guam and Puerto Rico) in exchange for an upfront fee of $350 million.

Pursuant to the Purchase and Sale Agreement, Royalty Pharma purchased the right to receive a percentage of net sales equal to a royalty rate of 13.8% on quarterly net sales of Niktimvo in the United States and its respective territories; provided that the royalty rate is subject to certain adjustments based on future aggregate net sales of the product in the United States and its respective territories, or the Revenue Participation Right. Aggregate payments made to Royalty Pharma in respect of the Revenue Participation Right will be capped at $822.5 million, or the Royalty Cap.

The Purchase and Sale Agreement contains customary representations, warranties and indemnities of the Company and Royalty Pharma and customary covenants relating to the royalty payments, including the grant of a back-up security interest in the purchased royalties and certain assets related to the product and restrictions on the incurrence of additional indebtedness and on the existence of liens on the Company’s assets related to the product.

Upon a change of control, the Company will have the right, but not the obligation, to repurchase the Revenue Participation Right at a repurchase price set forth in the Purchase and Sale Agreement. In addition, the Purchase and Sale Agreement provides that if certain events of default occur, including certain bankruptcy events or certain termination events with respect to the Company’s license agreement with UCB Biopharma Srl, Royalty Pharma may require the Company to repurchase Royalty Pharma’s interests in the Revenue Participation Right at a repurchase price equal to the Royalty Cap.

The Company assessed the Purchase and Sale Agreement and identified it as a sale of future revenue in the form of a debt instrument to be accounted for as a liability under Topic ASC 470, Borrower’s Accounting for Debt Modifications. The Company has elected to use the prospective method in its calculation of its effective interest rate and will update this calculation quarterly when there are changes in the projected sales. Issuance costs pursuant to the Purchase and Sale Agreement consisted primarily of bank and

legal fees and totaled $6.3 million. These issuance costs were recorded as a direct deduction to the carrying amount of the liability and will be amortized under the effective interest method over the estimated period the liability will be repaid. For the period ended June 30, 2026, the Company estimated an effective annual interest rate of approximately 13.02%. Over the course of the Purchase and Sale Agreement, the annual interest rate will be affected by the amount and timing of net Niktimvo revenue recognized and change in timing of forecasted net Niktimvo revenue. On a quarterly basis, the Company reassesses the expected timing of the net Niktimvo revenue, recalculates the amortization and effective interest rate, and adjusts the accounting prospectively, as needed. For the three and six months ended June 30, 2026, the Company recognized royalty interest expense of $12.1 million and $24.0 million, respectively. The Company made $15.3 million of payments pursuant to the Purchase and Sale Agreement during the six month period ended June 30, 2026.


	June 30, 2026			December 31, 2025
Current portion of royalty interest financing liability	$	—		$	—
Royalty interest financing liability, less current portion		350,000			350,000
Debt issuance costs		(5,974	)		(6,091	)
Total royalty interest financing liability, net	$	344,026		$	343,909