How far biotech stocks tend to move on, and into, an FDA decision: by company-size tier, across 763 decisions. Every 2024-26 FDA decision we can price, including nano-caps. Historical base rates, not predictions.
Median decision reaction (absolute)
The reaction falls cleanly with size: a nano-cap swings about 7× more than a large-cap. We define the reaction as the larger of the decision-day and next-day absolute move, because the FDA can announce either side of the close. This is the most consistent pattern in the dataset.
Median T-120 run-up into the date
Honest caveat: the run-up is far noisier than the reaction and does not fall neatly by size: mid-caps run up more than small-caps, and nano-caps have historically drifted down into the date. Run-up reflects many things (pipeline news, dilution, sector moves), so treat these as rough central tendencies, not a ladder.
Source: pdufa.bio internal cohort of 763 FDA decisions (2024-26) with complete price data, decision-day and trailing-120-day. Figures are medians of absolute moves; individual events vary widely. Not a prediction for any specific drug. Method: methodology · sources.
Cite this dataset. Free to reference with attribution (CC BY 4.0). Suggested citation: “pdufa.bio, PDUFA stock run-up & decision-day move by market-cap tier (2024-2026), n=763 FDA decisions, https://www.pdufa.bio/research/pdufa-stock-run-up-by-market-cap.” Journalists & researchers: email data@pdufa.bio for the underlying dataset or a custom cut (by therapeutic area or year).