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June 29 (Reuters) - Zymeworks ZYME.O said on Monday it will acquire Theravance Biopharma TBPH.O for $929 million in cash, marking the oncology-focused drugmaker's entry into the highly competitive respiratory disease segment.

The deal gives Zymeworks access to Theravance's FDA-approved drug Yupelri, a once-daily nebulized treatment for chronic obstructive pulmonary disease (COPD), putting it in competition with major drugmakers that dominate the segment, including GSK GSK.L, AstraZeneca AZN.L and Boehringer Ingelheim.

COPD is a progressive lung disease that obstructs airflow and makes breathing difficult.

Under the agreement, Zymeworks will buy all outstanding Theravance shares for $17 each, implying an about 3.6% discount to the stock's last close on Friday.

Zymeworks said Theravance has a 35% net profit share in Yupelri in the U.S., which is marketed in the country through a collaboration with Viatris VTRS.O.

In 2025, Yupelri's U.S. net sales were $266.6 million, up 12% from 2024. U.S. net sales rose 7% to $62.4 million in the first quarter of 2026.

The acquisition is expected to provide near-term cash flow following the deal's close, which is expected in the second half of 2026, Zymeworks said.

Theravance had said earlier this year it was exploring strategic alternatives, including a potential sale, after its experimental drug ampreloxetine for a rare disorder failed a late-stage trial, prompting a restructuring that could affect about half of its workforce.

Zymeworks said it will consider monetizing acquired assets, including ampreloxetine, with any proceeds from a potential ampreloxetine deal to be split 20% for Zymeworks and 80% for Theravance shareholders.