Day One Biopharmaceuticals, Inc. /
Mersana Therapeutics, Inc.
Day One Biopharmaceuticals, Inc. agrees to buy Mersana Therapeutics, Inc.
Source for the buyer and target: Mersana Therapeutics, Inc.
For the buyer and target.
“As previously disclosed in its Current Report on Form 8-K filed with the U.S. Securities and Exchange Commission (the “SEC”) on November 13, 2025, Mersana Therapeutics, Inc., a Delaware corporation (the “Company”), entered into an Agreement and Plan of Merger (the “Merger Agreement”), dated as of November 12, 2025, by and among the Company, Day One Biopharmaceuticals, Inc., a Delaware corporation (“Parent”), and Emerald Merger Sub, Inc., a Delaware corporation and a direct wholly-owned subsidiary of Parent (“Purchaser”).”
Published 6 Jan 2026
Open the sourceWhat happened
Day One Biopharmaceuticals, Inc. agreed to acquire Mersana Therapeutics, Inc., according to a filing dated Jan. 6, 2026. [01]
The source
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Day One Biopharmaceuticals, Inc. agrees to buy Mersana Therapeutics, Inc.
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Announced
“Day One Biopharmaceuticals, Inc. agrees to buy Mersana Therapeutics, Inc. Day One Biopharmaceuticals, Inc. agreed to acquire Mersana Therapeutics, Inc., according to a filing dated Jan. 6, 2026”
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