Will the FDA grant accelerated approval to z-rostudirsen in exon 51 skip-amenable DMD before 15 February 2027?
deadline 2027-02-15
confidence medium
tier 4 evidence
70%PolySignal estimate
Resolution criterion
Yes if the FDA approves the BLA by 15 February 2027 (Drugs@FDA or a Dyne release). A complete response letter, a postponed PDUFA date, or no decision by that date all count as no.
Verified starting state
BLA accepted for accelerated approval with priority review, PDUFA date 21 January 2027, based on the registrational expansion cohort of DELIVER, with dystrophin production as the primary endpoint. Dystrophin as a surrogate biomarker has been contested since the Sarepta approvals. (20 July 2026)
What pushes it up
- The FDA accepted the BLA under priority review with an established PDUFA target date of 21 January 2027, well before the 15 February 2027 resolution deadline [tier 1].
- Z-rostudirsen addresses a high unmet medical need in DMD patients amenable to exon 51 skipping based on DELIVER trial expansion cohort data [tier 4, article 0].
What pushes it down
- The BLA relies on dystrophin production as a surrogate biomarker, an endpoint that remains subject to intense FDA regulatory scrutiny and controversy [tier 1].
- Any major review amendment leading to a standard three-month PDUFA date extension would shift the decision to April 2027, causing the resolution to resolve negative [tier 1].
What would move this number most
Whether the FDA accepts the dystrophin biomarker data without issuing a Complete Response Letter or triggering a three-month PDUFA review extension.
How this number is built
| Deadline | 2027-02-15 |
| Base rate | 73% |
| Best evidence | tier 4 · 2 article(s) used |
| Independent runs | 68 · 72 (spread 4 pts) |
| Confidence | medium |
| Evidence cap | not triggered |
| Last revised | 2026-09-21 22:22 |
| Model | gemini-3.6-flash |
Sources consulted
Probability history
2026-09-21 22:22 70% 6 article(s) on file · gemini-3.6-flash
Reasons not recorded for this revision (detailed history has only been kept since recently).
2026-09-19 07:40 75% 4 article(s) on file · gemini-3.6-flash
Reasons not recorded for this revision (detailed history has only been kept since recently).