FDA staffers back riociguat approval, but with modified dose

On Tuesday (August 6), the US Food and Drug Administration’s Renal Drugs Advisory Committee will discuss German pharma major Bayer’s (BAYN: DE) New Drug Application for Adempas (riociguat coated tablet), for the treatment of 1) chronic thromboembolic pulmonary hypertension (CTEPH) World Health Organization (WHO) Group 4 to improve exercise capacity and WHO functional class and 2) pulmonary arterial hypertension (PAH) (WHO Group 1) to improve exercise capacity, improve WHO functional class and to delay clinical worsening.

Ahead of the meeting, FDA issued briefing documents from reviewers, who recommended approval of Adempas to treat PAH and CTEPH) with a modified dosing regimen. The drug is under Priority Review in the USA, with an October 8 Prescription Drug User Fee Act (PDUFA) date.

The reviewers said riociguat is effective for both indications but, because the compound causes dose-related decreases in blood pressure that can be "profound," they recommended approval of a modified dosing regimen. Bayer is seeking approval of riociguat for both indications with a starting dose of 1mg three times daily titrated up to a maximum dose of 2.5mg thrice daily. The reviewers proposed initiating therapy for both indications at 0.5mg three times daily and increasing the dose to a maximum of 1.5mg thrice daily. For CETPH, the reviewers said patients with high enough systolic blood pressure who do not experience an adequate response can be titrated to a maximum dose of 2.5mg three times daily.