Werewolf Therapeutics to merge with Ambros Therapeutics in all-stock deal
On August 21, 2026, Werewolf Therapeutics agreed to merge with Ambros Therapeutics, a clinical-stage biotechnology company developing neridronate for CRPS-1, in an all-stock transaction. Pre-merger Werewolf stockholders, other than private placement investors, are expected to own about 6.8% of the combined company, so the merger would substantially dilute their holdings. The deal is expected to close by the first quarter of 2027, subject to stockholder approvals, Nasdaq listing approval, an effective Form S-4 and other conditions.
Key points
- Pre-merger Ambros stockholders are expected to own about 71.7% of the combined company, and private placement investors about 21.5%.
- Implied valuations are $500.0 million for Ambros and $47.5 million for Werewolf.
- A concurrent private placement of $150 million in gross proceeds is expected to close with the merger.
- Termination fees are $20.0 million payable by Ambros and $1.9 million payable by Werewolf in certain circumstances.
The filing
Written by AI on Nov 9, 2026, 11:43 AM ET, from this filing only. Written later: this filing was briefed after the fact, when past filings were added to the site, so the brief may be read with hindsight; the filing itself is the record of what was known on August 21, 2026.
Briefs are written by AI from the filing text and can contain mistakes — open the filing before acting on anything. Impact (1-5) and tone are the AI's reading of the filing for shareholders, not a price forecast. Not investment advice.