Bayer Pharma and MSD have also issued a letter to healthcare professionals advising that patients with pulmonary hypertension associated with PH-IIP should not be treated with riociguat, considering interim results of the RISE-IIP study which showed an increased risk of mortality and serious adverse events among subjects receiving riociguat compared to those receiving placebo. Additionally, the available data did not indicate a clinically significant benefit in these patients.
The European Medicines Agency has previously issued a warning advising that riociguat should not be used in this population.