Atebrioz (zilurgisertib) was approved by the FDA on September 25, 2026 for fibrodysplasia ossificans progressiva (ages 12+), the 44th novel drug approval of 2026 on the FDA's Novel Drug Approvals list.
Verified against: FDA action day September 25, 2026 (NDA 221198 ORIG-1) · Announcement September 25, 2026 (FDA notice) · Goal date September 26, 2026 (Mirum 8-K).
Atebrioz (zilurgisertib) approved for fibrodysplasia ossificans progressiva in patients 12 and older: the FDA's notice was published September 25, 2026, the day before the Saturday September 26 PDUFA goal date.
The PDUFA goal date was Saturday, September 26, 2026, sourced to Mirum's 8-K of May 6, 2026. The FDA published its notice of the approval on Friday, September 25, 2026 (CDER News & Events, 2:46 PM ET); Mirum and Incyte announced it at 7:00 PM ET the same day. Neither document states the day the FDA acted and Drugs@FDA has not yet posted the approval letter, so the approval is recorded as no later than September 25 and no early/late margin is published until the letter posts. Atebrioz is a once-daily 100 mg oral ALK2 inhibitor, approved with Fast Track, Priority Review and Orphan Drug designations. The FDA issued a Rare Pediatric Disease Priority Review Voucher to Incyte. Incyte developed zilurgisertib and licensed it to Mirum for worldwide development and commercialization; an EU marketing authorization application is under review. Efficacy (PROGRESS Cohort 1, 63 patients): mean total new heterotopic ossification volume fell 3.2 cm3 on Atebrioz and rose 24.6 cm3 on placebo at week 24.
Run-up figures are the stock's own daily closing path over the 120 trading days before the decision, from our price history. Cohort move is the historical median absolute decision-day move for this market-cap tier. History, not a prediction.
Primary source: FDA notice, FDA Approves Third Treatment for Fibrodysplasia Ossificans Progressiva, September 25, 2026
FDA record of the action: the FDA approved on September 25, 2026, per NDA 221198 ORIG-1 (FDA letter). The sponsor announced it the same day. Action dates on pdufa.bio come from the FDA's own record, not the press release. Every FDA action we hold, by FDA date: FDA approval letters.
| Fund | Shares | Value at quarter end | Filing |
|---|---|---|---|
| BVF Inc. | 1,056,027 | $123.6 million | filed August 14, 2026 |
| Baker Bros. Advisors | 445,975 | $52.2 million | filed August 14, 2026 |
| RA Capital Management | 318,554 | $37.3 million | filed August 14, 2026 |
| Perceptive Advisors | 115,391 | $13.5 million | filed August 14, 2026 |
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Yes. The FDA approved the application for Atebrioz (zilurgisertib) on September 25, 2026, per the FDA's own record. The primary source is linked on this page.
Atebrioz (zilurgisertib) is a Mirum Pharmaceuticals, Inc. (MIRM) program. The FDA decision came on September 25, 2026; the FDA's own record of the decision is linked on this page.
Measured over the 120 trading days before the decision (T-120 to T-1), MIRM moved -7.1%. That is the recorded price path into this specific event. Historical measurement, not a prediction, and not investment advice.