Leucovorin greenlit for rare brain disorder, stops short of approval for autism

By HPN Staff

The Food and Drug Administration has approved Wellcovorin, also known as leucovorin calcium, a high-dose form of vitamin B9, to treat cerebral folate deficiency, a rare genetic neurological disorder.

The medication has long been used in oncology to reduce certain side effects associated with chemotherapy drugs. Regulators said evidence supports its use in patients whose bodies cannot properly transport folate into the brain.

Cerebral folate deficiency is an extremely rare condition affecting about one in 1 million people. Without sufficient folate reaching the brain, patients can experience seizures, developmental delays and movement disorders.

FDA Commissioner Dr. Marty Makary called the decision an important step for patients who previously had no approved treatment options.

“Today's approval represents a significant milestone for patients living with cerebral folate transport deficiency…which had no FDA-approved treatment options available until [leucovorin’s approval.”

Still, the FDA’s approval does not extend to treating autism. 

Why it matters

The approval comes as federal health officials place renewed focus on understanding autism spectrum disorder.

Health and Human Services Secretary Robert F. Kennedy Jr. has pledged to identify potential causes of autism by September 2025, an effort that has drawn significant attention from policymakers and researchers.

Last fall, Makary and several health officials discussed leucovorin’s potential in an opinion essay, noting that the drug could help people with cerebral folate deficiency and may also show promise for certain autism-related symptoms. The authors wrote that while leucovorin is not a cure, the drug “has demonstrated an improvement in speech-related deficits for autism.”

However, officials say there is not enough clinical evidence to support broader use for the condition.

Senior FDA officials also noted that the agency typically does not fund large clinical trials focused specifically on autism treatments. However, Makary and his co-authors wrote in the opinion essay that federal health officials plan to use existing research networks to support additional studies examining leucovorin’s potential effects.

The bigger picture

The decision comes amid growing concern about the rising prevalence of autism in the United States. The Centers for Disease Control and Prevention estimates that one in 31 children has been diagnosed with autism.

Data from the Autism and Developmental Disabilities Monitoring Network show autism diagnoses have increased significantly over the past two decades, reaching nearly five times the level reported when national tracking began in 2000.

Federal health officials have described the trend as alarming and say it highlights the need for more research into the possible environmental, genetic and metabolic factors that may contribute to autism.

While the FDA limited leucovorin’s approval to a rare neurological disorder, researchers have continued studying the drug because abnormalities in folate metabolism have been linked to autism and other neurodevelopmental conditions.