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What happens to a stock on its PDUFA date?
Page updated ·next FDA decision on the calendar·Data as of Nov 5, 2026 9:00 PM ET
A PDUFA decision is a binary catalyst: the FDA either approves the drug, issues a Complete Response Letter (CRL), or extends the date. The stock reaction is usually sharp, and historically its size scales inversely with company size.
On a PDUFA date the FDA approves the drug, issues a Complete Response Letter, or extends the review. Biotech stocks often move sharply on the outcome, and prices also tend to move in the weeks before the date, a documented run-up pattern whose size varies with company market cap. Outcomes are binary; moves are not guaranteed.
Decision-day move by company size (history)
Nano-cap (<$50M)8.0% median (n=122)
Micro-cap ($50M: $300M)4.7% median (n=312)
Small-cap ($300M: $2B)3.7% median (n=302)
Mid-cap ($2B: $10B)2.3% median (n=251)
Large-cap (>$10B)1.0% median (n=895)
Those are median absolute moves across our 1,883-decision run-up study (2020-26), the typical reaction, not a prediction for any one drug. Individual binary events can move a micro-cap 50%+ in either direction. There's also often a run-up into the date that fades near the decision; see our run-up-by-market-cap study.
Why size matters
A single approval can be the entire thesis for a one-drug micro-cap, but a rounding error for a diversified large-cap. That's why the same news moves them so differently. Related: how often the FDA approves drugs.
How much does a biotech stock move on its PDUFA date?
Historically the median decision-day move scales with size: about 8.0% for nano-caps, 4.7% micro, 3.7% small, 2.3% mid and 1.0% large (1,883-decision run-up study, 2020-26). Individual events can be far larger. These are historical base rates, not predictions.
Do biotech stocks run up before a PDUFA date?
Often, yes: there's frequently a run-up into the date that tends to fade near the decision, but it varies widely and is not guaranteed.