REGENXBIO is awaiting an FDA decision on its gene therapy RGX-121 for Hunter syndrome, with a verdict expected by February 8. The original deadline was November 9, but the agency extended its review to consider additional long-term clinical data submitted by the company.
Hunter syndrome, or mucopolysaccharidosis II, is a rare genetic disorder resulting from mutations in the iduronate-2-sulfatase (IDS) gene. This leads to a buildup of cellular waste and causes symptoms such as developmental delays and growth issues. RGX-121 aims to address this by delivering a functional IDS gene, restoring enzyme production. Data from the CAMPSIITE trial indicated an 86% median reduction in DS26, a biomarker linked to brain disease activity. According to REGENXBIO, DS26 levels approached normal during the study. The company has stated that RGX-121 could become the first one-time treatment targeting the root cause of Hunter syndrome.
Merck is seeking FDA approval to expand Keytruda’s use into platinum-resistant recurrent ovarian cancer. The agency’s decision is anticipated by February 20. Merck provided results from the KEYNOTE-B96 trial, which showed a 30% improvement in progression-free survival compared to placebo and a 24% reduction in all-cause mortality risk. Nearly all participants experienced toxicities related to the investigational regimen; death occurred in 0.9% of patients on Keytruda versus 1.6% on placebo. Keytruda has not previously been approved for any ovarian cancer indication.
Vanda Pharmaceuticals expects an FDA ruling on Bysanti for acute bipolar I disorder and schizophrenia by February 21. Bysanti contains milsaperidone, an active metabolite of iloperidone—the same ingredient as Vanda's already-approved Fanapt for these indications. In March 2025, Vanda noted: “Bysanti converts to Fanapt and that the two drugs have been shown in clinical studies to be ‘bioequivalent at both low and high doses.’” The company supports its application with Fanapt’s pharmacokinetic data and post-marketing experience involving over 80,000 patient-years.
Taiho Oncology is seeking approval for a combination of Inqovi with AbbVie and Roche’s Venclexta for treating acute myeloid leukemia (AML) in patients unsuitable for intensive chemotherapy. A decision is due by February 25. Results from the ASCERTAIN-V study showed complete response rates of up to 63.4%. Inqovi merges decitabine and cedazuridine; it was first approved for myelodysplastic syndromes in July 2020. Taiho CMO Harold Keer said: “If approved for this indication, Inqovi would become the first all-oral alternative to current AML therapies.”
Eton Pharmaceuticals’ ET-600 oral desmopressin solution awaits an FDA verdict by February 25 for diabetes insipidus treatment—a rare condition marked by excessive urination due to insufficient vasopressin production. Pivotal data demonstrated ET-600’s bioequivalence to existing products but CEO Sean Brynjelsen emphasized its dosing flexibility: “can accommodate the precise and titratable doses necessary for pediatric patients.”
Ascendis Pharma expects an FDA decision on TransCon CNP for achondroplasia (the most common cause of dwarfism) after a previous three-month delay; the new date is February 28. Achondroplasia stems from FGFR3 gene mutations affecting bone development; TransCon CNP mimics natural hormones that promote bone growth. The ACcomplisH trial showed statistically significant improvements in annualized growth velocity over placebo controls.
BioMarin seeks expansion of Palynziq’s label to include adolescents aged 12–17 with phenylketonuria (PKU), beyond its current adult indication, with an FDA action date set for February 28. The PEGASUS study found Palynziq reduced blood phenylalanine levels by nearly half after more than a year of treatment.
Sanofi and Regeneron are pursuing approval for Dupixent as a treatment for allergic fungal rhinosinusitis (AFRS), with a regulatory decision expected by February 28. AFRS involves chronic sinus inflammation triggered by fungal hypersensitivity; current treatments rely on surgery and steroids. Data from LIBERTY-AFRS-AIMS revealed Dupixent led to a notable improvement in nasal congestion compared with placebo at one year, also meeting secondary endpoints such as reducing nasal polyp size and decreasing reliance on other interventions.
