v3.26.1
Debt
3 Months Ended
Mar. 31, 2026
Debt  
Debt

6. Debt

On March 27, 2023, the Company entered into a note purchase agreement, or the “Note Purchase Agreement,” with RTW Investments LP and certain of its affiliates, or collectively, “RTW.” On March 29, 2023, the Company closed the transactions contemplated by the Note Purchase Agreement, and issued and sold $50.0 million principal amount of 6.0% Convertible Senior Notes due 2029, or the “2029 Convertible Notes,” to the holders. For more details on the agreement with RTW, see Note 11, “Debt,” to the Company’s audited consolidated financial statements, included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2025.

In accounting for the issuance of the 2029 Convertible Notes, the Company determined there were no embedded features, which require bifurcation between debt and equity components. As a result, the 2029 Convertible Notes are accounted for as a liability. As of March 31, 2026, the estimated fair value of the 2029 Convertible Notes was approximately $58.4 million based on level 2 inputs, including volatility and credit spread.

The net carrying amount of the 2029 Convertible Notes are as follows:

  ​ ​ ​

March 31, 2026

December 31, 2025

Original principal

 

$

50,000

$

50,000

Paid in kind (PIK) interest

9,810

8,927

Unamortized debt discount

(349)

(374)

Unamortized debt issuance costs

 

(1,269)

(1,362)

Total

 

$

58,192

$

57,191

The following table presents the total amount of interest cost recognized relating to the 2029 Convertible Notes:

Three months ended March 31, 

  ​ ​ ​

2026

  ​ ​ ​

2025

Contractual interest expense

$

884

 

$

832

Amortization of debt discount

25

23

Amortization of debt issuance costs

93

 

80

Total

$

1,002

 

$

935