Vancouver-based Zymeworks (Nasdaq: ZYME) announced this morning it has signed a definitive agreement to acquire Theravance Biopharma (Nasdaq: TBPH) for $17.00 per share in cash, a deal valued at roughly $929 million. The transaction adds YUPELRI® (revefenacin), the only nebulized once-daily LAMA approved for COPD maintenance therapy, to Zymeworks’ growing portfolio of partnered commercial assets.
The move is consistent with the strategy Zymeworks outlined earlier this year: pair royalty-generating assets with its internal R&D pipeline to create a more durable, self-funded business. The company has been building toward this kind of deal since pivoting away from a pure drug development model, and today’s announcement is the clearest sign yet that the strategy is gaining traction.
YUPELRI® has been on the U.S. market since 2019, co-promoted by Viatris and Theravance Biopharma. Full-year 2025 net sales came in at $266.6 million, up 12% over the prior year, with Q1 2026 sales of $62.4 million representing 7% growth year-over-year. Zymeworks will receive a 35% U.S. net profit share, which at current run-rates translates to roughly $60 million in annualized cash flow. Generic entry has been pushed to April 2039 following settlements with all filers, giving the asset a clear commercial runway.
Financing the deal involved some creativity. Zymeworks secured a $350 million non-recourse note from OMERS Life Sciences, structured so that 75% of the YUPELRI® profit-share cash flows service the debt. Critically, the note has no recourse to the rest of Zymeworks’ balance sheet. The company will contribute $219 million in existing cash, with Theravance Biopharma’s expected net cash balance of approximately $360 million at closing covering most of the remainder. A $100 million milestone payment from Royalty Pharma related to TRELEGY ELLIPTA® sales is expected in Q1 2027, which effectively cuts Zymeworks’ net cash outlay roughly in half.
Beyond YUPELRI®, the deal brings additional upside. Theravance Biopharma holds royalty interests on VIBATIV® through Cumberland, is eligible for up to $125 million in future YUPELRI® commercial milestones from Viatris, and carries approximately $2.5 billion in Irish tax attributes that Zymeworks intends to preserve for future use. A preclinical inflammation and immunology portfolio also transfers, though Zymeworks has signaled it will evaluate those assets against its broader pipeline priorities.
CEO Kenneth Galbraith framed the deal as core to the company’s longer-term vision of blending commercial cash flows with internal innovation, describing it as a way to fund next-generation therapies while supporting patients who need access today. The boards of both companies have unanimously approved the transaction.
Closing is expected in the second half of 2026, subject to Theravance Biopharma shareholder approval and regulatory clearance. Kirkland & Ellis is serving as legal counsel to Zymeworks, with TD Cowen advising on the OMERS note. Lazard and Evercore are advising Theravance Biopharma.