13. Royalty Purchase Agreement 

On July 31, 2025, the Company entered into a revenue participation right purchase and sale agreement (the “Royalty Purchase Agreement”) with Ligand Pharmaceuticals Incorporated (“Ligand”). Under the terms of the Royalty Purchase Agreement, in exchange for payment of $35.0 million (the “Investment Amount”), less certain reimbursable expenses, Ligand acquired the right to receive tiered royalty payments from the Company (the “Royalty Interest”) with respect to revenue (including certain licensing revenue) received by the Company in a calendar year in connection with worldwide net product sales, or other product revenue received, by the Company and its licensees (“Annual Net Sales”) of (a) AVIM Therapy (the “Primary Product”) and (b) Virtue SAB (the “Secondary Product” and together with the Primary Product, the “Products”) in the field of coronary artery treatment.

Pursuant to the Royalty Purchase Agreement, the Investment Amount shall be paid in two tranches: (i) $20.0 million was paid on August 4, 2025 (the “Ligand Closing”) and (ii) $15.0 million was payable and received on May 1, 2026 (the “Second Installment”), provided certain conditions have been met. In repayment of the Investment Amount, the Company will remit 17.0% of revenues related to the Products until an annual total of $17.0 million has been remitted to Ligand, thereafter the Company will remit (a) 4.0% of revenues related to the Primary Product in the field of hypertension treatment and (b) 4.0% of revenues related to the Secondary Product in the field of coronary artery treatment. In addition, under the terms of the Royalty Purchase Agreement, unless and until Ligand pays the Second Installment, Ligand shall only be entitled to 57.1% of the amounts it would otherwise be due under the Royalty Purchase Agreement. However, regardless of whether the Second Installment has been paid, under the terms of the Royalty Purchase Agreement, the percentages referenced in the second sentence of this paragraph will incrementally increase from 17.0% and 4.0% up to 20.0% and 7.0%, respectively, if the Company does not achieve certain enrollment milestones relating to the BACKBEAT clinical study through January 1, 2027.

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The Royalty Interest in respect of Annual Net Sales of the Products will end on the date in which no Product is being developed or commercialized by or on behalf of the Company, any of its affiliates, or any of its or their licensees or distributors and Ligand has received the last Royalty Interest payment payable under the terms of the Royalty Purchase Agreement. The obligations arising under the Royalty Purchase Agreement are secured by security interests in, and pledges over, the Royalty Interest, the Revenue Participation Right (as defined in the Royalty Purchase Agreement) and the Company’s interests in the Products and associated intellectual property rights, subject to certain agreed security principles, permitted liens and other customary exceptions and qualifications, and the security interests in the Products and associated intellectual property rights of the Company are subordinate in right of payment to the prior payment in full of the outstanding indebtedness under the 2024 LSA (as defined below). The Royalty Purchase Agreement contains customary representations, warranties and indemnities of the Company and Ligand, and customary covenants on the part of the Company. 

In connection with the sale of the Royalty Interest, and pursuant to the terms of the Royalty Purchase Agreement, on August 4, 2025, the Company issued to Ligand a warrant (the “Ligand Warrant”) to purchase up to 2,000,000 shares of the Common Stock (the “Ligand Warrant Shares”), at an exercise price equal to $3.67 per share. The exercise price of the Ligand Warrant and the number of Ligand Warrant Shares issuable upon exercise of the Ligand Warrant are subject to adjustments for stock splits, combinations, stock dividends or similar events. Pursuant to the terms of the Ligand Warrant, the Ligand Warrant Shares shall vest and become exercisable as follows: (i) 1,142,857 of the Ligand Warrant Shares (the “First Tranche”) vested upon issuance; and (ii) 857,143 of the Ligand Warrant Shares will vest on the date of payment of the Second Installment. In the event that the Second Installment is not paid, the Ligand Warrant shall only be exercisable with respect to the First Tranche. The Ligand Warrant is exercisable for ten years from the date of issuance.

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The Company accounted for its sale of royalty revenues to Ligand, pursuant to the Royalty Purchase Agreement, in accordance with ASC 470, Debt, which addresses situations in which an entity receives cash from an investor in return for an agreement to pay the investor a specified percentage of the revenue from a contractual right. The Company classified the proceeds received from the sale to Ligand as debt as the Company determined that it had significant continuing involvement in the generation of the cash flows to Ligand. Interest related to the Royalty Purchase Agreement will be recognized utilizing the effective interest method over the estimated term. When the Company receives the Second Installment, such Second Installment will also be recorded as a liability related to the sale of future royalties when they are received and amortized under the effective interest method over the estimated remaining term of the Royalty Purchase Agreement.

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The Company’s estimate of this total interest expense associated with the Royalty Interest resulted in an effective annual interest rate of approximately 23.3% as of March 31, 2026 and 23.1% as of December 31, 2025. This estimate contains significant assumptions that impact the interest expense that will be recognized over the royalty period. The Company will periodically assess the estimated amounts due and payable to Ligand and to the extent the amount or timing of such payments is materially different than the original estimates, an adjustment will be recorded prospectively to the condensed consolidated statements of operations and comprehensive loss. There are a number of factors that could materially affect the amount and timing of the royalty payments to be paid by the Company to Ligand and, correspondingly, the amount of interest expense recorded by the Company.

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The following table shows the activity of the Royalty Purchase Agreement for the three months ended March 31, 2026 (in thousands):

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