Debt	12 Months Ended
Debt	Dec. 31, 2025
Debt Disclosure [Abstract]
Debt	Debt Pharmakon Loan Agreement On April 17, 2023, the Company entered into a $450,000 Loan Agreement (the “Pharmakon Loan Agreement”) with BioPharma Credit Investments V (Master) LP and BPCR Limited Partnership, as lenders, and BioPharma Credit PLC, as collateral agent for the lenders. Certain of the Company’s wholly-owned subsidiaries were guarantors to the Pharmakon Loan Agreement. The Pharmakon Loan Agreement provided for an initial term loan in the principal amount of $300,000 (the “Tranche A Loan”) funded on April 17, 2023 (the “Tranche A Closing Date”). The Company used a portion of the proceeds from the Tranche A Loan to repay the $241,787 of outstanding indebtedness (principal and interest due as of April 17, 2023) under the then-existing Athyrium Credit Agreement (defined below) and to pay associated transaction costs and fees, and used the remaining net proceeds of $25,805 for other general corporate purposes. The Pharmakon Loan Agreement also provided for three additional term loan tranches, at the Company’s option, in principal amounts of $50,000 each (each a “Subsequent Tranche Loan” and, collectively with the Tranche A Loan, the “Pharmakon Term Loans” and each, a “Pharmakon Term Loan”). The Company chose not to request any Subsequent Tranche Loans and the options have since expired. The maturity date of the Pharmakon Loan Agreement was April 17, 2028 (the “Maturity Date”), the fifth anniversary of the Tranche A Closing Date. The Pharmakon Loan Agreement provided for quarterly interest-only payments until the Maturity Date, with the unpaid principal amount of the outstanding Pharmakon Term Loans due and payable on the Maturity Date. During the first 18 months following the Tranche A Closing Date, the Company had the option to make a portion of the applicable interest payment on the Tranche A Loan in-kind (a “Pharmakon PIK Interest Payment”) by capitalizing as principal up to 50% of the amount of interest accrued on the Tranche A Loan during the applicable interest period. The Pharmakon Term Loans bore interest at a rate equal to the three-month Secured Overnight Financing Rate (“SOFR”), which could be no less than 1.75%, plus 7.00%, per annum or, for each interest period in which a Pharmakon PIK Interest Payment was made, with respect to the Tranche A Loan, SOFR plus 7.25%, per annum. The Tranche A Loan accrued interest at an effective interest rate of 12.27% during the period in which the debt was outstanding for the year ended December 31, 2025, compared to 13.14% and 13.30% for the years ended December 31, 2024 and 2023, respectively. The Pharmakon Loan Agreement also contained representations and warranties and affirmative and negative covenants customary for financings of this type, as well as customary events of default. In 2025, the Company paid off in full the outstanding principal balance on the Pharmakon Term Loan in three separate prepayments totaling $323,704. In accordance with the Pharmakon Loan Agreement, the voluntary prepayments were subject to a prepayment premium equal to 3.00% of the principal amount of the Pharmakon Term Loan being prepaid. As a result, the Company incurred $9,711 and $173 in prepayment premiums and fees, respectively. Additionally, unamortized deferred financing costs of $7,448 associated with the Pharmakon Term Loan were written-off at the time of the repayments. Collectively, the prepayment premiums, fees, and unamortized deferred financing costs totaled $17,332 and are reflected as a one-time loss on extinguishment of debt in the Consolidated Statements of Comprehensive Income (Loss) for the year ended December 31, 2025. Interest expense and on the Tranche A Loan for the year ended December 31, 2025 was $23,274 and quarterly interest payments were paid at the end of each quarterly period. As of December 31, 2024, the Company had total borrowings of $300,000 under the Pharmakon Loan Agreement. Interest expense on the Tranche A Loan for the year ended December 31, 2024 was $39,874. As allowable under the Pharmakon Loan Agreement, the Company designated and accounted for 50% of the quarterly interest payments for each of the three months ended March 31, 2024 and June 30, 2024 as a Pharmakon PIK Interest Payment and the total amount of $10,041 was added to the outstanding principal balance of the borrowing. The remaining 50% of the total quarterly interest payments for the three months ended March 31, 2024 and June 30, 2024 and the full quarterly interest payments for the three months ended September 30, 2024 and December 31, 2024 totaling $29,833 in aggregate was paid at the end of each quarterly period. As of December 31, 2024, borrowings, including the Pharmakon PIK Interest Payments, totaled $323,704. As of December 31, 2023, the Company had total borrowings of $300,000 under the Pharmakon Loan Agreement. Interest expense on the Tranche A Loan for the year ended December 31, 2023 was $27,326. As allowable under the Pharmakon Loan Agreement, the Company designated and accounted for 50% of the quarterly interest payments for the year ended December 31, 2023 as a Pharmakon PIK Interest Payment and the total amount of $13,663 was added to the outstanding principal balance of the borrowing. The remaining 50% of the total quarterly interest payments of $13,663 was paid at the end of each quarterly period. As of December 31, 2023, borrowings, including the Pharmakon PIK Interest Payments, totaled $313,663. The fair value of the debt approximated its carrying value based on prevailing interest rates as of the balance sheet date and was considered as Level 2 in the fair value hierarchy. Debt fees and issuance costs incurred with the Tranche A Loan under the Pharmakon Loan Agreement totaled $11,147 and were deferred and amortized as interest expense on an effective interest rate method over the term of the Tranche A Loan. Deferred financing amortization of $1,387, $1,597, and $715 was recognized for the years ended December 31, 2025, 2024, and 2023, respectively. Athyrium Credit Agreement On December 7, 2020, the Company entered into a $200,000 Credit Agreement (the “Athyrium Credit Agreement”) with Athyrium Opportunities III Co-Invest 1 LP (“Athyrium”), as lender and as administrative agent for the lenders. Certain of the Company’s direct and indirect subsidiaries were guarantors to the Athyrium Credit Agreement. The Athyrium Credit Agreement provided for an initial term loan in the principal amount of $125,000 (the “Term A Loan”), which was received by the Company on December 7, 2020. The Athyrium Credit Agreement also provided for two additional term loans, at the Company’s option, in the respective principal amounts of $25,000 (the “Term B Loan”) and $50,000 (the “Term C Loan” and, collectively with the Term A Loan and the Term B Loan, the “Athyrium Term Loans”). Having achieved all required revenue-based milestones, the Company exercised its option to draw upon the additional funding available under the Athyrium Credit Agreement, borrowing the principal amounts of $25,000 under the Term B Loan and $50,000 under the Term C Loan. Both the Term B Loan and the Term C Loan were funded on July 29, 2022 in the aggregate principal amount of $75,000. The Company incurred deferred debt fees and issuance costs associated with the Term B and Term C Loans of $3,428. The Term B Loan and the Term C Loan were subject to all the provisions under the Athyrium Credit Agreement. The Athyrium Term Loans accrued interest at an effective interest rate of 13.71% during the period in which the debt was outstanding for the year ended December 31, 2023. Quarterly interest payments under the Athyrium Credit Agreement for the year ended December 31, 2023 totaled $8,476. Deferred financing amortization of $1,069 was recognized for the year ended December 31, 2023. On April 17, 2023, the outstanding principal of the Athyrium Term Loans, including the Athyrium PIK Interest Payments of $240,452 along with interest accrued of $1,335 for the first 17 days of the quarterly interest period ended June 30, 2023, was repaid with the funding received through the Pharmakon Loan Agreement. In accordance with the Athyrium Credit Agreement, upon the prepayment or repayment of all or any of the Athyrium Term Loans, the Company was obligated to pay an exit fee in an amount equal to 2.00% of the principal amount of the Athyrium Term Loans prepaid or repaid. In addition, each Athyrium Term Loan was subject to a 1.00% commitment fee at its respective borrowing date. As a result, the Company incurred prepayment and final payment fees of $17,261 upon repayment of the Athyrium Term Loans. Additionally, unamortized deferred financing costs of $11,758 associated with the Athyrium Term Loans were written off at the time of repayment. Collectively, the prepayment and final payment fees and unamortized deferred financing costs totaled $29,019 and are reflected as a one-time loss on extinguishment of debt in the Consolidated Statements of Comprehensive Income (Loss) for the year ended December 31, 2023.

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

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+ Details

BIOCRYST PHARMACEUTICALS INC 10-K