Daily close, T-120 (3/27/25) through T+5. Run-up high $9.89 on 9/9/25, low $6.97 on 4/17/25 (T-120 to T-1). FDA decision 9/11/25. Historical price action, not a forecast.
Positioning before the decision
On Aug 28, 2025, 14 days before the decision date, at-the-money options priced a move of ±6.3% through Sep 19, 2025 (the first listed expiry after the decision; ATM implied volatility 58%). The stock closed +2.7% at the first close across the decision and -2.1% 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 date2025-09-11
DrugSodium oxybate oral solution 500 mg/mL
IndicationCataplexy or excessive daytime sleepiness
Was Sodium oxybate oral solution 500 mg/mL approved by the FDA?
Yes. The FDA approved the application for Sodium oxybate oral solution 500 mg/mL on September 11, 2025. The primary source is linked on this page.
What was Sodium oxybate oral solution 500 mg/mL under FDA review for?
The application covered Cataplexy or excessive daytime sleepiness. The FDA approved the application on September 11, 2025.
How did AMRX stock react to the FDA decision?
On the decision day AMRX moved +2.7%. That is the recorded reaction to this specific event -- historical measurement, not a prediction, and not investment advice.