PDUFA Pulse Sept 21st 2026

Two live-board rows resolved before their printed dates.

Ultragenyx announced that FDA granted standard full approval to FAYUVI (rebisufligene etisparvovec-hopf, formerly UX111) on September 17 for pediatric patients with preserved neurodevelopmental function and MPS IIIA. The resubmitted gene-therapy BLA had been a CMC and facility-remediation story; it ended as full approval, not accelerated approval. Ultragenyx announcement.

Biofrontera announced September 14 that FDA approved Ameluz topical gel with the BF-RhodoLED lamp for adults with superficial basal cell carcinoma. That removes the September 28 sNDA from the board and turns the next question from label risk to launch execution. Biofrontera announcement.

Separately, FDA approved IntraBio’s Aqneursa for ataxia in adults and pediatric patients with ataxia-telangiectasia who weigh at least 15 kg. It is the first approved treatment for ataxia in A-T, but an expansion of an already approved medicine—not a new molecular approval. FDA decision.

Four scheduled September actions remain. Merck’s WINREVAIR label update is first. The late-month board then divides into three distinct questions: a pivotal Phase 2 package that missed its primary endpoint, a rare-disease NDA centered on biochemical and real-world evidence, and a pediatric expansion for an already marketed cardiology drug.

This week’s distinction: a nominally significant secondary result, a biochemical surrogate and a new label are not interchangeable forms of evidence.

Saturday targets: distinguish FDA action from the timing of the public announcement. A dash means no quantitative PDUFA Pulse estimate is published in this issue; the disclosed evidence requires a qualitative read rather than a false precision.

Date and status sources: Merck Q4 and full-year 2025 earnings release, Mirum and Incyte, Egetis, and Bristol Myers Squibb.

ULTRAGENYX / RARE · FAYUVI — STANDARD FULL APPROVAL SEP 17

FDA granted standard full approval to FAYUVI, formerly UX111, for neurologic manifestations of MPS IIIA in pediatric patients with preserved neurodevelopmental function. The approved single-dose AAV9 gene therapy is the first FDA-approved treatment for Sanfilippo syndrome type A.

The important regulatory read is the pathway. The prior CRL focused on CMC procedures, validation and manufacturing-facility observations. Ultragenyx now says the approval is supported by the Transpher A trial and long-term follow-up, including comparison with an external natural-history cohort.

The BLA leaves the board, but the post-decision constraints are substantial: product is expected to ship to Qualified Treatment Centers within 30–60 days, and Ultragenyx received a Priority Review Voucher. Before infusion, the label calls for anti-AAV9 antibody testing and does not recommend treatment at titers ≥1:100; no FDA-authorized test is currently available. The corticosteroid regimen starts the day before infusion at 1.0 mg/kg/day for eight weeks, followed by a taper of at least four weeks. In the safety database, 33 pediatric patients were treated and 27 received the recommended dose. The label also requires attention to liver, platelet and thrombotic-microangiopathy monitoring, hypersensitivity or infusion reactions, malignancy risk and three months of vector-shedding precautions. FDA label, company approval announcement.

BIOFRONTERA / BFRI · AMELUZ — sBCC EXPANSION APPROVED SEP 14

FDA approved Ameluz 10% topical gel with the BF-RhodoLED red-light lamp for adult superficial basal cell carcinoma. It is an sNDA approval, not a novel molecular entity: the approved change extends the existing drug-device photodynamic-therapy platform from actinic keratosis into a skin-cancer indication.

Biofrontera reports that its Phase 3 trial’s composite clinical and histological complete-response endpoint was met by 66% of Ameluz PDT-treated participants versus 5% with placebo PDT. The company plans the official sBCC launch for late fourth quarter 2026 through first quarter 2027, making the next investor read launch timing and dermatology adoption. Approval announcement.

INTRABIO · AQNEURSA — A-T ATAXIA INDICATION APPROVED SEP 18

FDA approved Aqneursa (levacetylleucine) oral suspension for ataxia in adults and pediatric patients with ataxia-telangiectasia who weigh at least 15 kg. It is the first approved treatment for ataxia in A-T, but Aqneursa itself was first approved in 2024 for neurological manifestations of Niemann-Pick disease type C. The label expansion, based on a 73-patient randomized crossover study, is a reminder to separate a first approved treatment in a disease from a first approval of the product. FDA decision.

Label scope: WINREVAIR’s October 2025 U.S. update, based on ZENITH, already added hospitalization for PAH, lung transplantation and death to the clinical-worsening events in its indication. HYPERION studied adults with PAH diagnosed within 12 months of screening, WHO functional class II or III, and intermediate or high risk of progression. The live question is how FDA writes that earlier-disease evidence into the next label. ZENITH update, HYPERION results.

Primary endpoint versus secondary evidence: In FOP, the sponsor reported an 81% reduction versus placebo in the proportion of participants developing new heterotopic-ossification lesions at Week 24, but the primary-endpoint p-value was 0.0986. Its total new-lesion-volume result was 99.9% lower with zilurgisertib, with a nominal p-value below 0.0001. FDA is therefore weighing the totality of a 63-patient pivotal Phase 2 package, not a straightforward primary-endpoint win. PROGRESS results.

Biochemical surrogate versus clinical effect: After Egetis’ October 2025 pre-NDA meeting, it says FDA comments led to a revised ReTRIACt statistical analysis plan and study close. The serum-T3 rate endpoint (PE1) was added to the earlier T3-rescue endpoint (PE2); alpha recycling tested PE1 first, then PE2. PE1 passed (p=0.034), but PE2 did not: four placebo participants versus one tiratricol participant after protocol-specified imputation (p=0.182). All eight placebo participants had a serum-T3 increase during withdrawal, versus values from −0.24 to 0.40 nmol/L in the seven continuing tiratricol participants. Triac Trial II also did not meet its neurodevelopmental primary endpoints versus historical controls. The U.S. review must translate this biochemical, historical and real-world record into a precise label. Egetis ReTRIACt release, Egetis EU indication and Triac Trial II.

Pediatric expansion / safety monitoring: CAMZYOS would extend an adult cardiology product to adolescents. Its adult label carries a boxed warning for heart failure from systolic dysfunction and a REMS requirement. In SCOUT-HCM’s 44 adolescents, no participant had an LVEF below 50% during the 28-week study period; the final pediatric label must still define the monitoring framework. SCOUT-HCM results.

Zilurgisertib and Emcitate are the live examples. Zilurgisertib’s primary endpoint did not reach statistical significance; its secondary lesion-volume analysis was nominally significant and large. Emcitate’s serum-T3 primary endpoint passed, but its T3-rescue primary endpoint did not, and Triac Trial II did not meet neurodevelopmental primary endpoints. Both packages contain real evidence, but neither is a clean clinical primary-endpoint win.

FDA can consider the totality of evidence, particularly in rare disease. But a numerical result on a secondary endpoint—or a passing biochemical endpoint—should not be rewritten as proof of clinical effect or treated as an automatic probability of approval.

The right question is: what did the study prospectively ask, what did it show, and what part of that record can support the exact label FDA is reviewing?

Editorial risk map—not a forecast of undisclosed FDA findings.

FAYUVI: Standard full approval on September 17 removes UX111’s September 19 resubmission clock. The approved indication is narrower than a generic Sanfilippo headline: pediatric patients with preserved neurodevelopmental function and neurologic manifestations of MPS IIIA. FDA label.

Ameluz + BF-RhodoLED: FDA approved the adult superficial basal cell carcinoma sNDA on September 14, resolving the former September 28 action date. Company announcement.

Aqneursa: FDA approved an A-T ataxia indication on September 18, one day before its September 19 target action date. The indication applies to adults and pediatric patients who weigh at least 15 kg. FDA decision, IntraBio filing-acceptance announcement.

The board is shorter, but the evidence quality is more uneven than its dates suggest. FAYUVI and Ameluz resolved early; Aqneursa added a first approved ataxia treatment in A-T. The four scheduled rows that remain do not share one regulatory question.

Latest pathway lesson: FAYUVI’s CMC and facility-remediation story ended in standard full approval. Its reader-facing question now is access through Qualified Treatment Centers and the on-label monitoring burden.

First live target: WINREVAIR today. Read the new label against the October 2025 ZENITH update, not in isolation.

Late-month evidence test: Zilurgisertib and Emcitate need a qualitative read. In each case, a real supportive signal exists, but it is not interchangeable with a clean clinical primary-endpoint win.

What this week answered: FDA actions can arrive early, and label expansions can be first treatments in a disease without being first approvals of a medicine. Aqneursa is the cleanest example.

For every FDA “yes,” read which patients, which claim, which operating constraint and which remaining obligation the decision covers.

Follow the FDA decision board. Forward this issue to someone tracking September’s dates without tracking the evidence behind them.

Informational only. Not investment advice. Biotech investing carries the risk of total loss.