5 FDA Headlines You Missed in November 2025

Published on: December 5, 2025

This FDA News Month in Review provides a round-up of regulatory decisions from November 2025.

Welcome back to our recap of this month's news and updates from the US Food and Drug Administration (FDA)!

November brought a series of impactful FDA decisions spanning rare disease, pediatrics, neuromuscular disorders, and cardiometabolic care—each marking a meaningful expansion in therapeutic options for historically underserved patient populations. The month opened with the approval of doxycitine and doxribtimine (Kygevvi), the first treatment for thymidine kinase 2 deficiency, offering survival and functional benefits in an ultra-rare mitochondrial disorder with no prior therapies. Soon after, linaclotide became the first FDA-approved option for pediatric irritable bowel syndrome with constipation (IBS-C) in patients ≥7 years old, supported by efficacy signals consistent with adult outcomes. Mid-month, the agency issued significant safety-driven changes to ELEVIDYS, restricting its use to ambulatory patients with Duchenne muscular dystrophy (DMD) and adding a Boxed Warning following reports of acute liver failure in non-ambulatory recipients.

Regulators also advanced innovation in lipid and renal disease. The approval of plozasiran introduced the first apoC-III–targeting siRNA therapy for familial chylomicronemia syndrome, offering meaningful reductions in triglycerides, apoC-III, and pancreatitis risk with quarterly dosing. Closing the month, sibeprenlimab received accelerated approval for IgA nephropathy after demonstrating a more than 50% placebo-adjusted reduction in proteinuria at one year, adding momentum to a rapidly evolving treatment landscape ahead of confirmatory eGFR data. Collectively, these decisions signal an FDA increasingly focused on precision mechanisms and high-need populations across a diverse therapeutic spectrum. Here’s a concise overview of the key FDA decisions and updates from November 2025.

Want to hear from the experts? Look for our Related Content links underneath blurbs for insight into how this decision might influence practice moving forward.

FDA News Recap: November 2025

1. FDA Approves Kygevvi, First Treatment for Thymidine Kinase 2 Deficiency

On November 3, 2025, UCB announced the FDA approved doxycitine and doxribtimine (Kygevvi) as the first therapy for thymidine kinase 2 deficiency (TK2d). Based on phase 2 clinical data, retrospective analyses, and an expanded access program, Kygevvi demonstrated improved survival and functional outcomes, including markedly lower mortality compared with untreated patients. The combined nucleoside therapy supports mitochondrial DNA replication and skeletal muscle function in this ultra-rare mitochondrial disorder.

2. FDA Approves Linaclotide (Linzess) Capsules for Pediatric IBS-C

On November 5, 2025, Ironwood Pharmaceuticals announced the FDA approved linaclotide (Linzess) for pediatric patients ≥7 years of age with irritable bowel syndrome with constipation (IBS-C), making it the first therapy authorized for IBS-C in this age group. Based on extrapolated adult efficacy data and a 12-week randomized pediatric trial, linaclotide 145 mcg once daily demonstrated reductions in abdominal pain and increases in spontaneous bowel movements consistent with adult outcomes. The safety profile was similar to that observed in adults, with diarrhea reported as the most common adverse event.

3. FDA Issues New Boxed Warning, Limiting ELEVIDYS to Ambulatory DMD

On November 14, 2025, the FDA announced new safety warnings and labeling revisions for delandistrogene moxeparvovec-rokl (Elevidys), restricting its indication to ambulatory patients with Duchenne muscular dystrophy.

Based on postmarketing safety reports, including fatal cases of acute liver failure in non-ambulatory recipients, the agency added a Boxed Warning for serious liver injury and mandated a postmarketing observational study with serial liver function monitoring. Updated guidance includes enhanced recommendations for hepatic and cardiac monitoring, cautions regarding corticosteroid-associated risks, and new contraindications for certain patient populations.

4. FDA Approves Plozasiran for Adults With Familial Chylomicronemia Syndrome

On November 18, 2025, Arrowhead Pharmaceuticals announced the FDA approved plozasiran (Redemplo) for reducing triglycerides in adults with familial chylomicronemia syndrome (FCS). Based on the phase 3 PALISADE trial and supportive phase 2 SUMMIT data, plozasiran significantly lowered fasting triglycerides and apoC-III levels and reduced acute pancreatitis risk, with dosing once every 3 months. The small-interfering RNA therapeutic demonstrated a favorable tolerability profile and represents the first approved therapy targeting apoC-III reduction for FCS.

5. FDA Awards Accelerated Approval to Sibeprenlimab in IgA Nephropathy

On November 25, 2025, Otsuka Pharmaceutical announced the FDA approved sibeprenlimab (Voyxact) to reduce proteinuria in adults with primary IgA nephropathy at risk for disease progression. Based on results from the phase 3 VISIONARY trial, sibeprenlimab produced a 54.3% placebo-adjusted reduction in 24-hour urine protein-to-creatinine ratio after 12 months, with consistent effects across clinical subgroups. The APRIL-targeting antibody adds to the growing therapeutic landscape for IgA nephropathy and received accelerated approval pending full 2-year eGFR results expected in 2026.