No new bone where it does not belong: a daily pill slows an ultra-rare childhood disease

About 900 people in the world live with FOP, a rare genetic condition in which bone slowly grows inside muscles, tendons and other soft tissue, steadily locking joints and stealing movement. There is no cure, so slowing that extra bone matters enormously — especially in childhood, when it first takes hold. In a 25-child trial run by Mirum Pharmaceuticals, children aged 6 to under 12 who took the daily pill zilurgisertib for 24 weeks saw their total extra-bone volume shrink by 8.09 cubic centimetres on average, while it grew by 9.14 in children on placebo. Not one treated child grew a new patch of bone, and their joint movement improved. The pill was generally well tolerated, with no new safety worries. It is already approved in the USA for patients aged 12 and over; Mirum now plans to ask regulators in the first half of 2027 to extend it to these younger children.

SDG 3 · Good health and well-being — Mechanism: tech innovation