Sidley Represents Werewolf Therapeutics in Merger with Ambros Therapeutics and Concurrent US$150 Million Private Placement

Sidley represented Werewolf Therapeutics, Inc. (Nasdaq: HOWL), a biotechnology company developing therapeutics designed to stimulate the body’s immune system for the treatment of cancer, in its definitive merger agreement with Ambros Therapeutics, Inc. in an all-stock transaction. In connection with the merger, the companies also secured commitments for an oversubscribed US$150 million concurrent private placement from a syndicate of leading healthcare-dedicated investors. Upon completion of the merger, the combined company will operate as Ambros Therapeutics and is expected to trade on Nasdaq under the ticker symbol “AMBX.” The combined company will focus on advancing Ambros Therapeutics’ neridronate development program for Complex Regional Pain Syndrome Type 1 (CRPS-1), including its ongoing pivotal Phase 3 clinical trial. The transaction is expected to close by the first quarter of 2027, subject to stockholder approval and other customary closing conditions.

The Sidley team was led by Rosemary G. Reilly (Emerging Companies and Venture Capital) and John H. Butler (M&A), and included Craig Hilts, Rebecca Nauta, and Emily Ivers (Emerging Companies and Venture Capital); Ryan Sanguigni (M&A); Adam Welland and Karena B. Kong (Technology and Life Sciences Transactions); Sonia Gupta Barros, Joseph K. Chung, Katherine A. Walsh, and Kayla M. West (Capital Markets); Torrey Cope and Julea Lipiz (Food, Drug and Medical Device); Elizabeth T. Burns (Employee Benefits and Executive Compensation); Suresh Advani and Sophie Arkusinski (Tax); and Mary K. Marks (Antitrust and Competition).