Y-mAbs to go private in $412M deal with SERB Pharmaceuticals

Y-mAbs Therapeutics will go private after SERB Pharmaceuticals agreed to buy the cancer drug developer for $412M in equity value. The stock surged over 100% after trading resumed from a premarket halt.

SERB Pharmaceuticals (SERB) has agreed to acquire Y-mAbs Therapeutics (YMAB) in an all-cash transaction valued at approximately $412 million, as announced on Tuesday. The acquisition includes Y-mAbs' lead commercial asset, DANYELZA, an FDA-approved treatment for high-risk neuroblastoma. The deal is expected to close by the fourth quarter of 2025 [1].

Under the terms of the merger agreement, SERB will commence an all-cash tender offer to purchase all outstanding shares of Y-mAbs common stock. Holders of Y-mAbs common stock would receive $8.60 per share in cash, representing a premium of approximately 105% to Y-mAbs’ closing share price on August 4, 2025, the last full trading day prior to the transaction announcement [1].

The acquisition strengthens SERB's rare oncology portfolio, which includes Voraxaze, Vistogard, and Xermelo. The deal, unanimously approved by Y-mAbs' Board, is expected to close by Q4 2025 [2]. Approximately 16% of Y-mAbs stockholders have agreed to tender their shares. SERB will commence the tender offer by August 19, 2025, subject to customary conditions including Hart-Scott-Rodino approval [1].

Following the announcement, YMAB stock surged over 100% after trading resumed from a premarket halt, reflecting investor optimism about the deal and the potential for synergies between the two companies [2].

References:
1. [1] https://seekingalpha.com/news/4478430-serb-pharmaceuticals-to-acquire-y-mabs-therapeutics-for-412m
2. [2] https://www.stocktitan.net/news/YMAB/