New Drug Offers Treatment Option for Rare Bone Disease

The US Food and Drug Administration has approved a new pill for a rare bone disorder, offering patients a potential treatment option to slow the disease's progression. The drug, zilurgisertib, sold under the brand name Atebrioz, has been approved for use in patients aged 12 and above with fibrodysplasia ossificans progressiva, or FOP. FOP is a condition where muscles, tendons, and ligaments gradually transform into bone, resulting in limited mobility and severe disability.

Atebrioz functions by inhibiting ALK2, a protein that is abnormally active in most FOP patients, driving the out-of-skeleton bone formation. The recommended dosage is 100mg once a day. FOP is typically diagnosed in childhood, with approximately 300 individuals in the United States and 900 worldwide currently living with the condition.

Mirum Pharmaceuticals, the company behind Atebrioz, anticipates launching the drug in October, with the pricing to be announced at that time. The company's CEO, Chris Peetz, believes the medication could be a game-changer for patients, potentially halting the progressive accumulation of bone. The FDA's approval was based on a study involving 63 patients, demonstrating that Atebrioz effectively reduced new bone formation compared to a placebo at the 24-week mark.

Current treatment options for FOP include Ipsen's oral drug Sohonos and Regeneron's monthly infusion Pasatru. Analysts suggest that Atebrioz might become a preferred option due to its oral administration, superior efficacy, and favorable safety profile.