Shionogi & Co. Ltd. has agreed to acquire Apnimed's 50% ownership in their joint venture, Shionogi-Apnimed Sleep Science, LLC (SASS), making it wholly-owned by Shionogi.25
Apnimed will receive a $100 million upfront cash payment, plus a $50 million milestone payment upon achievement of a development milestone for SASS-002 (sulthiame), and tiered royalties on future sales of SASS products.25
The transaction, announced on March 24, 2026, is expected to close in Q2 2026 and strengthens Apnimed's focus on its lead OSA drug AD109, with NDA submission planned for Q2 2026.2
SASS, formed in 2023, develops novel pharmacologic therapies for obstructive sleep apnea (OSA) and sleep disorders; Apnimed's AD109 program is not included.12
Sources:
1. https://apnimed.com/article/apnimed-announces-launch-of-joint-venture-with-shionogi-to-develop-novel-pharmacologic-therapies-for-obstructive-sleep-apnea-and-other-sleep-disorders/
2. https://www.biospace.com/press-releases/apnimed-announces-strategic-monetization-of-shionogi-apnimed-sleep-science-sass-joint-venture-stake-for-150m-and-royalties-strengthening-focus-on-its-wholly-owned-osa-program-ad109
5. https://www.shionogi.com/global/en/news/2026/03/20260324.html