FDA approves Wellcovorin (leucovorin calcium) as the first treatment for FOLR1-related cerebral folate deficiency in adults and children, addressing a rare neurological genetic disorder.
Written By: Karthik Teja Macharla, PharmD
Reviewed By: Pharmacally Editorial Team
The U.S. Food and Drug Administration (FDA) has approved an expanded indication for Wellcovorin (leucovorin calcium) tablets for the treatment of cerebral folate deficiency in both adult and pediatric patients with a confirmed variant in the folate receptor 1 (FOLR1) gene. The decision marks the first FDA-approved therapy for this rare genetic neurological disorder.
The approval was granted through a supplemental new drug application submitted by GlaxoSmithKline (GSK) and is effective as of March 9, 2026, according to the official FDA approval letter.
Cerebral folate deficiency is a rare neurological condition characterized by impaired transport of folate, an essential vitamin for brain development and function, into the central nervous system. Patients with FOLR1-related cerebral folate deficiency often develop severe neurological complications including developmental delays, movement disorders, seizures, and other progressive neurological symptoms.
The FDA’s decision was based on a systematic review of published scientific literature, including case reports with patient-level data and mechanistic evidence demonstrating clinical benefit of leucovorin in patients with the disorder.
These findings helped establish evidence of effectiveness despite the challenges of conducting large clinical trials in ultra-rare diseases.
“Today’s approval represents a significant milestone for patients living with cerebral folate transport deficiency due to the FOLR1 variant, a rare genetic condition that has had no FDA-approved treatment options until today,” said FDA Commissioner Marty Makary. He added that the therapy may benefit some individuals with developmental delays accompanied by autistic features associated with the condition.
The FDA worked closely with GSK to update the product’s labeling to include essential scientific and clinical information supporting the safe and effective use of leucovorin in patients with CFD-FOLR1.
According to Tracy Beth Hoeg, M.D., Ph.D., Acting Director of the FDA’s Center for Drug Evaluation and Research, the approval highlights the agency’s ability to use alternative evidence sources when traditional clinical trials are not feasible. She noted that the decision demonstrates how observational and real-world evidence can support regulatory approval when a therapy shows clear clinical benefit compared with the natural course of a disease.
Leucovorin treatment is associated with several potential adverse effects, including pruritus, rash, urticaria (hives), dyspnea, rigors, and impaired thermoregulation.
Rarely, patients may experience anaphylaxis, a severe allergic reaction that requires immediate medical attention.
The FDA emphasized that the approval addresses a significant unmet medical need for patients with this ultra-rare genetic condition and reflects the agency’s ongoing commitment to accelerating access to treatments for serious diseases.
Reference
FDA Approves First Treatment for Patients with Cerebral Folate Transport Deficiency, 10 March 2026, https://www.fda.gov/news-events/press-announcements/fda-approves-first-treatment-patients-cerebral-folate-transport-deficiency
Supplement Approval, NDA 018342/S-15, https://www.accessdata.fda.gov/drugsatfda_docs/appletter/2026/018342Orig1s015ltr.pdf
About Writer
Karthik Teja Macharla, PharmD,
He is a Pharm.D. graduate with a strong interest in clinical research, pharmacovigilance, and medical writing. In his words, he is passionate about converting complex medical information into clear, evidence-based scientific communication, committed to contributing to patient safety and advancing healthcare through accurate and impactful medical content.