Zydus launches in U.S. MSN Labs generic of Bayer’s PAH drug

Zydus Lifesciences has launched in the U.S. market Riociguat tablets, in multiple strengths, developed and manufactured by MSN Laboratories.

The two companies are the first to launch the product, which is a generic version of Bayer’s Adempas. Approved by the U.S. Food and Drug Administration as a generic equivalent of Adempas tablets, in all five strengths, Riociguat tablets are indicated for treatment of persistent or recurrent chronic thromboembolic pulmonary hypertension after surgical treatment, or inoperable CTEPH; and pulmonary arterial hypertension (PAH).

“Being first to market with generic riociguat is a milestone for our U.S. business and for patients with pulmonary hypertension. It reflects the strength of our complex-generics pipeline, our ability to execute day-one launches in specialty categories and the strength of our partnerships that complement our commercial reach in the U.S.” Zydus Lifesciences Managing Director Sharvil Patel said in a release on Monday.

MSN Laboratories founder and CMD MSN Reddy said “Riociguat is a technically demanding molecule and bringing the first generic to the U.S. demonstrates the depth of MSN’s integrated API and formulation R&D and the scale of our manufacturing. Together with Zydus’ established U.S. commercial platform, we are confident of delivering consistent, high-quality supply of this important therapy.”

Thus far, Riociguat was available in the U.S. only as the branded product. Sales of drug are not reported by IQVIA. According to Bayer’s annual report 2025, the global sales of Adempas were around Euro 745 million (approximately $850 million) in 2025, Zydus said.