Bayer presents strong Ph III riociguat data, which met primary endpoint in PAH

Germany’s Bayer (BAYN: DE) HealthCare unit yesterday announced positive data for riociguat from the pivotal Phase III study PATENT-1, showing the drug met its primary endpoint by demonstrating a statistically significant improvement in the six-minute walk test (6MWT), a predictor of improved outcome in patients suffering from pulmonary arterial hypertension (PAH).

Assuming eventual market approval for riociguat, the drug would join a PAH market expected to grow to a value of $3.57 billion by 2015, according to GlobalData. The current market is dominated by Tracleer (bosentan) – due to lose patent protection in 2015 - from Switzerland’s Actelion, which announced yesterday its US regulatory filing for follow on PAH treatment macitentan (see separate story today).

Patients treated with riociguat showed an improvement of 36 meters (95%-CI [20-52 meters] p<0.0001) from baseline after 12 weeks compared with placebo. The data will be presented today 9October 23) in the late-breaking abstracts session at CHEST 2012, the annual meeting of the American College of Chest Physicians (ACCP) in Atlanta, USA.