Asset Acquisition	3 Months Ended
Asset Acquisition	Mar. 31, 2024
Business Combination and Asset Acquisition [Abstract]
Asset Acquisition	Note 6. Asset Acquisition On February 5, 2024, we entered into a purchase agreement with MorphoSys AG and MorphoSys US Inc., a wholly-owned subsidiary of MorphoSys AG (together with MorphoSys AG, “MorphoSys”), under which we gained exclusive global rights to tafasitamab, a humanized Fc-modified CD19-targeting immunotherapy marketed in the United States as MONJUVI (tafasitamab-cxix) and outside of the United States as MINJUVI (tafasitamab). We previously had the rights to tafasitamab outside of the United States under our prior collaboration and license agreement with MorphoSys entered into in January 2020, which has now been terminated; therefore, this new agreement gave us all of the remaining global rights to tafasitamab. Under the terms of the purchase agreement, we made a payment of $25.0 million to MorphoSys and gained global development and commercialization rights for tafasitamab along with MONJUVI inventory. We will recognize revenue and costs for all U.S. commercialization and clinical development and MorphoSys will no longer be eligible to receive future milestone, profit split and royalty payments under the now-terminated collaboration and license agreement with MorphoSys. We evaluated the set of activities and assets acquired under the purchase agreement, and concluded that it did not meet the definition of a business because the acquired set did not include a substantive process. Therefore, the transaction was accounted for as an asset acquisition and the total purchase price, inclusive of direct transaction costs, was allocated to the acquired MONJUVI inventory, in accordance with applicable accounting guidance. Under the purchase agreement, we have also become the successor to MorphoSys under its collaboration and license agreement with Xencor, Inc. (“Xencor”), pursuant to which Xencor granted MorphoSys an exclusive, worldwide license, including the right to sublicense under certain conditions, for tafasitamab. Xencor is entitled to receive up to $186.5 million in future contingent development and regulatory milestones, and up to $50.0 million in sales milestones. Furthermore, Xencor is eligible to receive tiered royalties on global net sales of tafasitamab in the single-digit to sub-teen double-digit percentage range. Our royalty obligations continue on a country-by-country basis until the later to occur of the expiration of the last valid claim in the licensed patent covering tafasitamab in such country, or 11 years after the first sale thereof following marketing authorization in such country. The term of the Xencor collaboration agreement will continue until all of our royalty payment obligations have expired, unless terminated earlier. The Xencor collaboration agreement may be terminated by either party upon written notice to the other party immediately in the event of the other party’s insolvency or upon 120 days’ written notice for the other party’s uncured material breach (or upon 30 days’ written notice in the case of a breach of a payment obligation). Moreover, we may terminate the Xencor collaboration agreement without cause upon 90 days’ advance written notice to Xencor. In the event that (i) we terminate this agreement for convenience or (ii) Xencor terminates due to our material breach, our challenge of Xencor’s licensed patents or our insolvency, worldwide rights to develop, manufacture and commercialize licensed products, including tafasitamab, revert back to Xencor.