Mirum and Incyte’s Atebrioz approved for FOP in US

The medication aims to reduce the volume of heterotopic ossification (HO) in these individuals and is administered orally at a recommended dose of 100mg once daily.

Developed by Incyte and licensed to Mirum for global commercialisation, Atebrioz acts as an activin receptor-like kinase 2 (ALK2) inhibitor, targeting the key pathway involved in FOP. This rare genetic disorder causes abnormal bone formation in soft tissues due to variants in the ACVR1 gene, leading to potential significant disability.

Mirum Pharmaceuticals CEO Chris Peetz said: “Today marks an important milestone for people living with FOP, bringing a new treatment option to adult and paediatric patients living with this devastating disease.

“At Mirum, we are driven to serve rare disease communities where the unmet need is significant and the opportunity to make a difference is profound. The approval of Atebrioz reflects what can be achieved when industry, researchers and patient communities work together, and we remain committed to fostering that spirit of collaboration in FOP.”

The FDA’s approval was supported by data from the PROGRESS study’s cohort 1. In this trial, patients treated with zilurgisertib showed a mean reduction in HO lesion volume of 3.2cm³, in contrast to a 24.6cm³ increase in the placebo group after 24 weeks. The effects persisted through a 48-week open-label extension.

During the 24-week controlled study period, common side effects of zilurgisertib included headache, upper respiratory tract infections, arthralgia, epistaxis and nausea. These were generally mild to moderate, with no participants needing to discontinue or reduce their dose.

The PROGRESS study is ongoing, with enrolment concluded for children aged six to under 12 in cohort 2 and underway for those aged two to under six in cohort 3.

Atebrioz will be accessible through Mirum Access Plus (MAP), a support programme providing insurance and financial assistance, along with educational resources.

It is expected to be available in the US starting October, with costs potentially as low as $0 per month for eligible patients.

Additionally, the FDA has awarded Incyte a rare paediatric disease priority review voucher, which can be used for a future drug application.

Atebrioz’s marketing authorisation application is currently under evaluation by the European Medicines Agency (EMA).

In February 2025, Mirum’s Ctexli (chenodiol) has gained the FDA approval for treating adults with cerebrotendinous xanthomatosis (CTX), a rare lipid storage disease.

The post Mirum and Incyte’s Atebrioz approved for FOP in US appeared first on Pharmaceutical Business review.