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 3 evidence
73%Asturna 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 has granted Priority Review for the BLA, which accelerates the review timeline [1]
- The PDUFA date of 21 January 2027 falls before the 15 February 2027 deadline [1]
- The FDA has an established, though debated, precedent of granting accelerated approval for DMD therapies based on dystrophin as a surrogate biomarker [1]
What pushes it down
- Dystrophin as a surrogate biomarker remains a point of contention within the FDA, which could lead to a Complete Response Letter or a request for more data [1]
- Any major amendment to the BLA during the review process could trigger a 3-month PDUFA extension, which would push the decision date past the 15 February 2027 deadline [1]
What would move this number most
The primary uncertainty is whether the FDA will accept the dystrophin production data from the DELIVER trial as sufficient for accelerated approval and whether the review stays on its original timeline.
How this number is built
| Deadline | 2027-02-15 |
| Base rate | 73% |
| Best evidence | tier 3 · 1 article(s) used |
| Independent runs | 70 · 75 (spread 5 pts) |
| Confidence | medium |
| Evidence cap | not triggered |
| Last revised | 2026-10-10 09:14 |
| Model | gemini-3-flash-preview |
Sources consulted
Probability history
2026-10-10 09:14 73% 7 article(s) on file · gemini-3-flash-preview
- What pushes it up. The FDA has granted Priority Review for the BLA, which accelerates the review timeline [1]
- What pushes it up. The PDUFA date of 21 January 2027 falls before the 15 February 2027 deadline [1]
- What pushes it up. The FDA has an established, though debated, precedent of granting accelerated approval for DMD therapies based on dystrophin as a surrogate biomarker [1]
- What pushes it down. Dystrophin as a surrogate biomarker remains a point of contention within the FDA, which could lead to a Complete Response Letter or a request for more data [1]
- What pushes it down. Any major amendment to the BLA during the review process could trigger a 3-month PDUFA extension, which would push the decision date past the 15 February 2027 deadline [1]
- What would move this number most. The primary uncertainty is whether the FDA will accept the dystrophin production data from the DELIVER trial as sufficient for accelerated approval and whether the review stays on its original timeline.
2026-10-06 09:19 73% 8 article(s) on file · qwen/qwen3.8-27b (Groq)
- What pushes it up. The BLA has been accepted for accelerated approval with a priority review designation, which typically indicates a streamlined and faster review process [tier 4, corroborated by hand-verified state].
- What pushes it down. The use of dystrophin production as a primary surrogate biomarker has been contested since previous Sarepta approvals, which could lead to regulatory hesitation or a complete response letter [tier 1 context].
- What would move this number most. Whether the FDA will accept dystrophin production as a sufficient surrogate endpoint for accelerated approval in this specific context, given historical regulatory scrutiny of this biomarker.
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).