Overview
- Day One agreed to buy Mersana for $25.00 per share in cash plus contingent value rights of up to $30.25 per share, via a tender offer followed by a second‑step merger.
- Mersana’s board unanimously recommends stockholders tender their shares, and executives, directors and Bain Capital‑affiliated holders totaling about 8.5% have signed support agreements.
- The tender offer has not yet commenced and closing is targeted by the end of January 2026, contingent on a majority of shares being tendered and required U.S. regulatory approvals.
- Day One cited Emi‑Le (emiltatug ledadotin), a B7‑H4‑directed ADC with early Phase 1 activity in adenoid cystic carcinoma, as the key asset driving the transaction.
- The company said it expects to finance the acquisition with existing cash; following the announcement, Mersana shares jumped while Day One shares declined in afternoon trading.