Rebuilt daily·next FDA decision on the calendar·Data as of Nov 5, 2026 9:00 PM ET
Clinical/Endpoint CRL, RGX-121 (MPS II): FDA cited uncertainty on study eligibility criteria, natural-history external-control comparability, and the surrogate endpoint (CSF HS D2S6).
Price into the decision (T-120)
Daily close, T-120 (8/22/25) through T+5. Run-up high $15.98 on 1/22/26, low $8.03 on 8/26/25 (T-120 to T-1). FDA decision 2/8/26. Historical price action, not a forecast.
CRL reasonClinical/Endpoint, RGX-121 (MPS II): FDA cited uncertainty on study eligibility criteria, natural-history external-control comparability, and the surrogate endpoint (CSF HS D2S6).
ValidationOutcome consistent with price; primary-source verification in progress.
Market-cap tierSmall
Cohort decision-day move (history)3.7% median (n=302)
Cohort move is the historical median absolute decision-day move for this market-cap tier across our run-up study. History, not a prediction.
13F reports list long positions in common stock at quarter end, are due 45 days later, and show no short positions or later trades. Notes, warrants and other instruments are not counted as shares.
Questions
Was RGX approved by the FDA?
Not in this review cycle. A Complete Response Letter, declining to approve the application for RGX in its current form, was announced on February 8, 2026. A CRL is not final; the primary source is linked on this page.
How did RGNX stock react to the FDA decision?
On the decision day RGNX moved -0.2%. That is the recorded reaction to this specific event. Historical measurement, not a prediction, and not investment advice.