Related Party Transactions |
12 Months Ended |
|---|---|
Dec. 31, 2023 | |
| Related Party Transactions [Abstract] | |
| Related Party Transactions | 17. Related Party Transactions Zenas BioPharma Limited: The Company is a party to option and license agreements with Zenas, a related party. The Company considers Zenas to be a related party because (i) Tellus BioVentures LLC (“Tellus”), whose sole member is a significant shareholder in the Company and serves as Chairman of the Board of Directors of the Company, is also a significant shareholder in Zenas and serves as Chief Executive Officer and Chairman of the Board of Directors of Zenas and (ii) Fairmount Healthcare Fund LP and Fairmount Healthcare Fund II LP (together, the “Fairmount Funds”), who are significant shareholders in the Company and have a seat on the Board of Directors of the Company, are also significant shareholders in Zenas and have a seat on the Board of Directors of Zenas. As of December 31, 2023, Tellus and affiliated entities owned approximately 10%, and the Fairmount Funds and affiliated entities owned approximately 13% of the Company’s outstanding shares. See Note 13 for more information. In connection with these agreements, the Company recognized $2.8 million and $6.4 million within the license revenue – related party line item in the consolidated statements of operations and comprehensive loss for the years ended December 31, 2023 and 2022, respectively. As of December 31, 2023, the Company recorded a related party receivable of $0.3 million, unbilled related party receivable of $0.2 million, current deferred related party revenue of $0.1 million and noncurrent deferred related party revenue of $0.7 million on its consolidated balance sheet. As of December 31, 2022, the Company recorded a related party receivable of $4.7 million, unbilled related party receivable of $0.9 million, current deferred related party revenue of $0.1 million and noncurrent deferred related party revenue of $0.8 million on its consolidated balance sheet. In 2020, Zenas issued 156,848 common shares to the Company in exchange for the Zenas Option. The Company determined that the fair value on the date of issuance and as of December 31, 2023 and 2022, respectively, was not material to its consolidated financial statements. The Company used the measurement alternative as the measurement attribute for accounting for the Zenas common shares which does not require it to assess the fair value of the common stock at each reporting period as the fair value of the Zenas common shares is not readily determinable nor is there a reliable source for observable transactions from which the Company could determine a fair value. In addition, the Company does not have ready access to significant events occurring at Zenas. If the Company does identify observable price changes in orderly transactions for the identical or similar common shares of Zenas, the Company will measure the common shares at fair value as of the date that the observable transaction occurred. On March 13, 2023, the Fairmount Funds issued promissory notes in the aggregate principal amount of $377 thousand to Former Dianthus at an interest rate of 4.5% per annum. On March 15, 2023, Former Dianthus repaid principal and interest in the amount of $377 thousand to the Fairmount Funds in satisfaction of its obligations under the promissory notes. |