As of March 31, 2026, the Company had outstanding fixed-rate notes for an undiscounted aggregate principal amount of $1.5 billion. The notes detailed below incur interest to be paid semi-annually in arrears. The following table summarizes information regarding the Company’s debt:


	March 31, 2026		December 31, 2025
5.5% senior unsecured notes due in February 2034 (the 2034 Notes)	$	850,000	$	—
Unamortized discount net of deferred offering costs	(17,407)		—
2034 Notes, net	832,593		—

1.25% senior subordinated convertible notes due in May 2027 (the 2027 Notes)	$	600,000	$	600,000
Unamortized discount net of deferred offering costs	(2,311)		(2,824)
2027 Notes, net	597,689		597,176

Long-term debt, net	$	1,430,282	$	597,176

Fair value of fixed-rate debt(1) :
2034 Notes	$	839,239	$	—
2027 Notes	578,823		576,267
Total fair value of fixed-rate debt	$	1,418,062	$	576,267

(1) The fair value of the Company’s fixed-rate long-term debt is based on open-market trades and classified as Level 1 in the fair value hierarchy. For additional discussion of fair value measurements, see Note 1 – Business Overview and Significant Accounting Policies to the Company’s Consolidated Financial Statements included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2025.


	Three Months Ended March 31,
		2026		2025
Coupon interest expense		$	8,805	$	1,875
Accretion of discount on convertible notes		487		485
Amortization of debt issuance costs		279		27
Total interest expense on debt		$	9,571	$	2,387

In February 2026, the Company issued $850.0 million in aggregate principal amount of 5.5% senior unsecured notes with a maturity date of February 15, 2034, and the proceeds from the issuance were deposited into an escrow account. The 2034 Notes bear interest at the rate of 5.5% per annum. Interest is payable semi-annually in cash in arrears on February 15 and August 15 of each year, beginning August 15, 2026. Net proceeds from the offering were $832.3 million. The Company incurred $17.7 million of issuance costs, which were deferred and will be amortized over the life of the 2034 Notes and recorded as interest expense.

The indenture governing the Notes contains customary covenants that, among other things, restrict, with certain exceptions, the ability of the Company and its subsidiaries to incur additional debt, pay dividends, make certain other restricted payments, incur debt secured by liens, dispose of assets, engage in consolidations and mergers or sell or transfer all or substantially all of its assets. The offer and sale of the 2034 Notes have not been registered under the Securities Act or any state securities laws and were offered only to qualified institutional buyers as defined in Rule 144A under the Securities Act.

See Note 10 - Debt to the Company’s Consolidated Financial Statements included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2025 for additional information related to the Company’s 2027 Notes and existing credit facility entered into in August 2024.

In December 2025, the Company entered into a debt financing commitment letter and related fee letter with certain lenders, pursuant to which the lenders committed to provide the Company with debt financing up to approximately $3.7 billion (the Bridge Commitment) in the form of a 364-day senior secured bridge loan facility (Bridge Facility), the proceeds of which would be available for the acquisition of Amicus.