Eight for eight. The FDA had eight rare disease decisions due between September 19 and September 30, 2026, according to Trial Friend, and it approved all of them by the end of the month. Six came ahead of their action dates.
The decisions bunched up because applications accepted in early 2026, some of them resubmissions with a six-month clock, stacked their deadlines into a single 12-day window. Four of the conditions had never had an approved treatment. Each now has one.
Four first-ever treatments
Ionis won approval on September 3 for Zanvastro (zilganersen) in Alexander disease, 19 days early. The FDA said patients aged 5 and older on the drug walked significantly faster at week 61 than untreated patients.
On September 17, Ultragenyx’s one-time gene therapy Fayuvi (UX111) became the first approved treatment for Sanfilippo syndrome type A. Ultragenyx said the FDA’s 2025 rejection cited manufacturing and facility issues, not the clinical data, and that its resubmission included up to 8 years of follow-up. The label covers Sanfilippo type A only, and only children with preserved function.
IntraBio’s Aqneursa, already approved for Niemann-Pick disease type C, was cleared on September 18, a day early, as the first therapy for ataxia-telangiectasia. The approval covers adults and children weighing at least 15kg and rests on a 73-patient trial.
Egetis Therapeutics’ Emcitate followed on September 28 as the first treatment for MCT8 deficiency, in which thyroid hormone cannot reach the cells that need it. The approval addresses the body’s excess thyroid hormone, not the developmental disability.
New options in other diseases
Scholar Rock’s Isembyld (apitegromab) was approved on September 11 for spinal muscular atrophy, 19 days early. It is meant to work alongside the SMN-directed therapies, and is only for patients 2 and older already on one.
Lyrfigtu (lirafugratinib), from Elevar, won approval on September 23 for the fusion-driven form of bile duct cancer. On September 25, Atebrioz (zilurgisertib) from Mirum and Incyte was approved for fibrodysplasia ossificans progressiva in patients 12 and older, the third option for the condition. The companies expect it to be available in October. On September 30, Bristol Myers Squibb’s Camzyos was extended to adolescents weighing at least 30kg with obstructive hypertrophic cardiomyopathy.
Early decisions and rejections
Early action is more common than people expect, and a rejection does not always end a program. Some complete response letters concern manufacturing rather than clinical data, according to the companies involved. UX111 had been rejected before and ended in approval. Extensions happen too: Capricor’s Duchenne therapy saw its date pushed from August to November 22.
Approval is not access. Insurance decisions, manufacturing release and, for gene therapies, activation of qualified treatment centers typically take weeks to months. Many companies open patient support programs within days of a decision.
