IONS PDUFA Date: Zilganersen (ION373)

Name: Zilganersen (ION373) FDA decision
Start: 2026-09-22
End: 2026-09-22

Updated August 7, 2026·next FDA decision on the calendar

FDA decision (PDUFA) target 2026-09-22 · Ionis Pharmaceuticals Inc. · Alexander disease

More CNS & Neurology FDA decisions →All September 2026 PDUFA dates →

The story

Zilganersen (ION373) is under FDA review to treat Alexander disease. Balance sheet: about 25 months of cash, runway ~25 mo (estimated).

Full PDUFA calendar ->Every upcoming FDA decision date, by month NRXP . 2026-07-29Same area: Neurology . KETAFREE LNTH-florquinitau . 2026-08-13Same area: Neurology . Florquinitau (MK-6240)TLX . 2026-09-11Same month decision . TLX101-Px

Plain-English summary compiled by pdufa.bio from public FDA, SEC and company sources. Informational only - not investment advice.

IONS run-up into the PDUFA (last ~120 days)

Price path to 2026-06-19. Green = local high, red = low/sell-off. Historical price action, not a forecast.

Key facts

FDA PDUFA target date2026-09-22

Drug / candidateZilganersen (ION373)

IndicationAlexander disease

CompanyIonis Pharmaceuticals Inc.

Market-cap tierLarge

Cohort decision-day move (history)±1% median

ClinicalTrials.govNCT04849741 · Fast Track Designation (FTD)

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See the full 2026 PDUFA calendar →

FAQ

When is the IONS PDUFA date?

The FDA PDUFA target date for IONS (Ionis Pharmaceuticals Inc.) is 2026-09-22 for Zilganersen (ION373). Dates are company/FDA-sourced and can slip. Verify against primary filings.

What is IONS's drug Zilganersen (ION373)?

Zilganersen (ION373) is Ionis Pharmaceuticals Inc.'s candidate under FDA review for Alexander disease.

What typically happens to a large-cap stock into a PDUFA date?

Historically, large-cap names had a median decision-day move around ±1% (763-PDUFA cohort, 2024-26). This is historical context by market-cap tier, not a prediction for this drug.

Decision-day move · large-cap cohortn=790 · median +0.0% · 50% up

Distribution of next-day % moves after the FDA decision for large-cap PDUFAs (2020–26). Red = down, green = up, blue = flat (±3%). Historical dispersion, not a forecast.