Monday's regulatory sleight of hand
Yesterday, I reported on the US President’s autism claims. Within hours of Trump’s promised “biggest medical announcement in US history,” the FDA published a notice approving GlaxoSmithKline’s version of leucovorin — a drug GSK had previously withdrawn from consideration and stopped manufacturing in 1997. The timing was not coincidental.
The approval wasn’t based on new autism research. Instead, the FDA cited a review of just 40 patients with cerebral folate deficiency, a rare metabolic disorder that shares some neurological symptoms with autism. GSK, despite abandoning the drug decades ago, still holds the regulatory paperwork and has agreed to update the label at the FDA’s request.
This is how medical announcements get manufactured: find an existing drug, locate a plausible mechanism, expedite the bureaucracy, and present it as breakthrough science.
The science behind the soundbite
Leucovorin, also known as folinic acid, is a form of folate (vitamin B9). It’s been used for decades to counteract the toxic effects of certain cancer drugs and to treat specific types of anaemia. The drug itself isn’t controversial — it’s the application that raises questions.
Some researchers have found that up to three-quarters of autistic children have genetic variations affecting folate processing, or autoimmune issues blocking folate transport to the brain. A handful of small studies have suggested leucovorin might improve verbal skills, social interaction, and reduce irritability in some children.
But here’s the reality check: the evidence comes from four small randomised trials, each using different doses, measuring different outcomes, and in one case, targeting only children with specific genetic variants. Dr. David Mandell from the University of Pennsylvania says leucovorin “might well be a possible treatment for some children with autism, but the evidence we have supporting it… is really, really weak.”
When off-label becomes on-brand
Doctors have already been prescribing leucovorin off-label for autism — using a drug approved for one condition to treat another. This is standard medical practice when evidence suggests potential benefit. The difference now is political endorsement masquerading as scientific validation.
The Autism Science Foundation states the research “is still in very early stages, and more studies are necessary before a definitive conclusion can be reached.” This is the measured language actually required when handling neurodiversity — cautious, conditional, and demanding replication.
Compare that to Trump’s promise of revealing autism’s cause and cure. One approach follows evidence; the other follows expedience.
The autism treatment industrial complex
This is where our attention should actually be.
What’s happening with leucovorin illustrates a broader pattern: the endless search for pharmaceutical solutions to neurological differences. Every few years, a new compound emerges as the potential breakthrough — oxytocin, bumetanide, suramin, now leucovorin. Each generates headlines, hope, and eventually, limited results.
This isn’t to dismiss legitimate research or potential benefits for some individuals. Folate metabolism is genuinely important for brain function, and some autistic people may have processing differences that respond to supplementation. But presenting preliminary findings as definitive answers serves neither science nor the autism community.
The focus on biochemical interventions also deflects from what many autistic people actually need: acceptance, accommodation, and support systems that work with neurological differences rather than trying to eliminate them.
What parents actually need to know
If you’re a parent of a neurodivergent child and considering leucovorin, the current evidence suggests:
Some children might benefit, particularly those with folate processing difficulties
The research is preliminary and inconsistent
Side effects are generally minimal, but individual responses vary
No treatment works for everyone, and autism doesn’t require “fixing”
More importantly, be wary of treatments promoted through political announcements rather than peer-reviewed research. Science doesn’t follow electoral cycles, and breakthrough discoveries rarely align with news conferences.
The real breakthrough would be societies that accommodate neurological diversity without needing to medicalise or cure it first.
Citations
GSK plc — GSK to submit label update for Wellcovorin (leucovorin) at US FDA’s request
U.S. Food and Drug Administration — FDA Takes Action to Make a Treatment Available for Autism Symptoms
University of Pennsylvania —David S Mandell
Autism Science Foundation — Statement on Leucovorin and Autism Treatment
SUNY Downstate Medical Center — Folate Metabolism Research in Autism
