Daily close, T-120 (4/8/25) through T+5. Run-up high $42.86 on 7/18/25, low $24.47 on 4/15/25 (T-120 to T-1). FDA decision 9/23/25. Historical price action, not a forecast.
Positioning before the decision
On Sep 9, 2025, 14 days before the decision date, at-the-money options priced a move of ±26.9% through Oct 17, 2025 (the first listed expiry after the decision; ATM implied volatility 106%). The stock closed +3.6% at the first close across the decision and +17.7% five trading days on. A straddle priced weeks out covers ordinary movement plus the event, so this is the move the options market priced through that expiry, not the event-implied move alone. How this compares across 1,000+ decisions.
Decision facts
FDA decision date2025-09-23
DrugApitegromab - (SAPPHIRE)
IndicationType 2 and Type 3 Spinal Muscular Atrophy (SMA)
Not in this review cycle. On September 23, 2025 the FDA issued a Complete Response Letter, declining to approve the application for Apitegromab - (SAPPHIRE) in its current form. A CRL is not final; the primary source is linked on this page.
What was Apitegromab - (SAPPHIRE) under FDA review for?
The application covered Type 2 and Type 3 Spinal Muscular Atrophy (SMA). The FDA declined to approve the application in its current form on September 23, 2025.
How did SRRK stock react to the FDA decision?
On the decision day SRRK moved +3.6%. That is the recorded reaction to this specific event -- historical measurement, not a prediction, and not investment advice.