PDUFA Dates September 2026: 11 FDA Decisions on the Calendar

Update September 4, 2026: The Ionis zilganersen PDUFA resolved early — approved September 3 as ZANVASTRO (see our approval coverage).

September is the busiest PDUFA month of the second half: 11 FDA target action dates across rare disease, oncology, neurology, and hematology, ranging from binary small-cap events to mega-cap label expansions. Here is the full calendar, ranked by how much each decision can actually move the underlying stock. We track all of these live on the FDA calendar page.

The calendar at a glance

Date	Company (Ticker)	Drug	Application	Indication
Sept 3	Advicenne	Sibnayal	NDA	Distal renal tubular acidosis
Sept 11	Telix (TLX)	Pixclara (TLX101-Px)	NDA	CNS tumor imaging
Sept 18	Nuvalent/GSK	Zidesamtinib	NDA	ROS1+ NSCLC (approved early — see below)
Sept 19	Ultragenyx (RARE)	UX111	BLA	Sanfilippo syndrome type A
Sept 21	Merck (MRK)	Winrevair	BLA	Pulmonary arterial hypertension
Sept 22	Ionis (IONS)	Zilganersen	NDA	Alexander disease
Sept 26	Incyte/Mirum (MIRM)	Zilurgisertib	NDA	Fibrodysplasia ossificans progressiva
Sept 27	Elevar	Lirafugratinib	NDA	FGFR2+ cholangiocarcinoma
Sept 27	Praxis (PRAX)	Relutrigine	NDA	SCN2A/SCN8A DEEs — moved to Dec 27
Sept 28	Egetis	Emcitate (tiratricol)	NDA	MCT8 deficiency
Sept 30	ScholarRock (SRRK)	Apitegromab	BLA	Spinal muscular atrophy
Sept 30	Bristol Myers Squibb (BMY)	Camzyos sNDA	sNDA	Adolescent oHCM
Sept (TBD)	Roivant/Priovant	Brepocitinib (LISRAYA)	NDA	Dermatomyositis — Approved Aug 27
Sept (TBD)	Takeda/Protagonist	Rusfertide (MIMRYLO)	NDA	Polycythemia vera — Approved Aug 28

Four September entries are already consumed: Nuvalent’s zidesamtinib was approved early on July 22 as Jideytro after GSK’s $10.6 billion acquisition closed, Takeda’s Orzeyful (oveporexton) narcolepsy approval landed August 5, Roivant’s brepocitinib (LISRAYA) was approved August 27 for dermatomyositis — five weeks ahead of its window — and Takeda/Protagonist’s rusfertide (MIMRYLO) was approved August 28 for polycythemia vera. See our MIMRYLO coverage.

The three decisions that can move stocks 30%+

Ultragenyx UX111, September 19 (BLA resubmission, gene therapy). The highest-conviction small-cap binary of the month. UX111 (rebisufligene etisparvovec) is a one-time AAV9 therapy for Sanfilippo syndrome type A, a fatal pediatric neurodegenerative disease with no approved treatment. The Transpher A data showed a 63.98% median reduction in CSF heparan sulfate (p<0.001) with a +23.2-point Bayley-III cognitive effect in early-treated children versus natural history. RARE at roughly $2.5 billion market cap is a company where one approval moves the equity — gene therapy pricing at $2 to $4 million per patient means even 200 annual patients is $400 to $800 million. Full thesis in our UX111 deep dive. The prior CRL on this BLA is the risk that keeps it from being a free lunch.

Praxis Relutrigine, December 27 (was September 27 — extended). Praxis Precision Medicines (PRAX) filed relutrigine for SCN2A and SCN8A developmental and epileptic encephalopathies — severe pediatric seizure disorders with no approved therapies for most patients. The FDA extended the review period by three months in June, pushing the PDUFA from September 27 to December 27, 2026, after Praxis submitted additional sensitivity analyses the agency deemed a major amendment. See our relutrigine primer.

ScholarRock Apitegromab, September 30 (BLA, Priority Review). Apitegromab, an anti-myostatin antibody for spinal muscular atrophy, would be the first add-on therapy to existing SMN treatments (Zolgensma, Spinraza, Evrysdi) — a multi-billion-dollar market of patients already on therapy who still lose motor function. The SPR1NT/SAPPHIRE data showed meaningful motor-function improvement on top of standard of care. SRRK is one of the few September names where approval transforms the commercial story rather than confirming it.

The rest, ranked by materiality

Ionis Zilganersen, September 22 (NDA, Priority Review). An antisense oligonucleotide for Alexander disease, a fatal leukodystrophy with no treatment. IONS at ~$7 billion cap absorbs this quietly — the platform story matters more than any single rare disease NDA — but a approval adds a second approved ASO in 2026 and validates the neuro pipeline.

Mirum/Incyte Zilurgisertib, September 26. An ALK2 inhibitor for FOP, one day after Regeneron’s Pasatru approval in the same disease on August 19 (see our Pasatru analysis). Two FOP drugs in five weeks would be remarkable for a disease with 800 U.S. patients. Competitive dynamics will decide which wins the small market. Primer: Mirum zilurgisertib.

Elevar Lirafugratinib, September 27. An FGFR2 inhibitor for second-line cholangiocarcinoma, competing with Incyte’s Pemazyre and Taiho’s Lytgobi. A niche oncology approval at a private-ish sponsor — low index impact. Our primer.

BMY Camzyos adolescent sNDA, September 30. Label expansion for symptomatic obstructive hypertrophic cardiomyopathy in adolescents. Immaterial to BMY’s ~$110 billion cap but strategically extends the franchise before competitors arrive.

Merck Winrevair sBLA, September 21. The pulmonary arterial hypertension label expansion — Winrevair is one of 2025-2026’s fastest-growing launches, and this sBLA broadens the addressable population. For context on why PAH is suddenly crowded, see the Sotatercept competitive landscape coverage in our FDA calendar archive.

Egetis Emcitate (Sept 28), Advicenne Sibnayal (Sept 3), Telix Pixclara (Sept 11). Ultra-rare and imaging plays at small sponsors — genuine binaries for the companies involved, minimal index impact.

Roivant/Priovant Brepocitinib (LISRAYA) — APPROVED August 27. A TYK2/JAK1 inhibitor for dermatomyositis, cleared roughly five weeks ahead of its September 30 window as the first targeted therapy for the disease. See our LISRAYA coverage.

How to trade the month

September’s calendar is dominated by rare disease filings with strong biomarker data and Priority Review — historically the highest-approval-rate category in PDUFA outcomes. The pattern that repeats: the run-up arrives in the two weeks before the date, and the decision-day move depends on how much of the approval was already priced. UX111 has been the market’s known September trade since the BLA resubmission; expect crowded positioning. The under-owned setups are the Sept 26-28 cluster (Mirum, Elevar, Praxis, Egetis) where attention splits four ways. For the full framework — entry timing, AdCom reads, exit discipline — see how to trade FDA catalysts and what a PDUFA date is.

We will update each decision live on the FDA calendar as dates resolve.

Sources: Cardiology Advisor September PDUFA roundup | Assyro PDUFA Calendar 2026 | checkrare 2026 orphan drug PDUFA dates