Mirum Pharmaceuticals said the FDA approved Atebrioz, an oral therapy for fibrodysplasia ossificans progressiva, an ultra-rare disorder characterized by progressive bone formation in soft tissue. The approval makes Atebrioz the third FDA-approved treatment option for FOP. Mirum acquired Atebrioz from Incyte earlier this year, positioning the company to expand its footprint in rare disease therapies through an additional commercial product. The approval adds a new dosing form that may offer advantages over existing options for a patient population with limited alternatives.