CBDV: The Cannabinoid Being Tested for Autism and Epilepsy

CBDV now turns up in hemp products alongside CBD. A drugmaker spent years testing it as an epilepsy medicine, and researchers are still testing it in autism.

The results so far are thin. The finished human trials have not shown a clear benefit, and the main pediatric autism trial has not reported yet.

Key takeaways

• CBDV, short for cannabidivarin, is a non-intoxicating cannabinoid that is usually a minor part of the cannabis profile.
• It is a homolog of CBD with a side chain two carbons shorter, and it was first identified in 1969.
• In mice and rats, CBDV worked as an anticonvulsant in a broad range of seizure models.
• In a trial of 162 adults with focal seizures, CBDV did no better than placebo.
• A single dose of CBDV shifted brain connectivity in autistic men, but no trial has yet shown that it eases autism symptoms.
• A pediatric autism trial of CBDV is still recruiting, with its main results not expected before 2027.
• No CBDV medicine is approved, while Epidiolex, a purified CBD drug, won FDA approval in 2018.

Cannabidivarin, the shorter cousin of CBD

So what is CBDV? Cannabidivarin is a non-intoxicating cannabinoid, identified for the first time in 1969, and it is a homolog of CBD with the side chain shortened by two carbon units. CBD carries a five-carbon tail, and CBDV carries three. CBDV is usually a minor constituent of the cannabis profile, although enhanced levels have been reported in feral plants from northwest India and in hashish from Nepal.

Most modern cannabis carries very little of it. Both THCVA and CBDVA, the acid forms of the two varins, are produced in very low quantities by most cannabis cultivars, a 2020 analysis of about 17,600 lab-tested cultivars notes, and 96.6% of the entries in that dataset had no CBDV value at all. A 2018 study of a genetic collection notes that varins can make up a larger share in plants of Asian and African origin, though they are typically found at low levels in contemporary domesticated forms. The same short side chain makes varins hard to breed for, which is why THCV-rich strains are harder to breed than CBG-rich ones.

We do not test or list CBDV for our strains, which, like most modern seeds, are bred and sold on their THC. Two of our lines do trace back to the regions where varins turn up more often, Durban Poison, an F1 line bred from South African landrace genetics at 27% THC, and Afghan Hash Plant Auto, an autoflower built on Afghan genetics. Neither page lists a CBDV figure, so treat any CBDV in them as unknown.

CBDV vs. CBD, side by side

The CBDV vs. CBD comparison starts with structure and ends with evidence. In animal tests, a 2012 study found CBDV to be an effective anticonvulsant in a broad range of seizure models in mice and rats, with no effect on motor function. A 2013 follow-up with CBDV-rich extracts found anticonvulsant effects that were not mediated by the CB1 cannabinoid receptor, the receptor behind the THC high.

Epidiolex is made from purified cannabidiol, or CBD, and the FDA approved it in 2018 for Lennox-Gastaut syndrome and Dravet syndrome. No medicine based on CBDV has been approved.

Epilepsy trials so far

The biggest test came in adults. In a phase 2 trial published in 2021, 162 people with inadequately controlled focal seizures took CBDV, titrated from 400 to 800 mg twice daily, or a placebo on top of their usual epilepsy drugs. Seizures fell by 40.5% on CBDV and by 37.7% on placebo, and a treatment difference from placebo was not observed. The authors noted that the placebo response was high, which may reflect what participants expected from CBDV.

The safety results were mixed:

• CBDV was generally well tolerated, and the three most common side effects were diarrhea, nausea and somnolence.
• At least one side effect was reported by 72.8% of people on CBDV and 48.1% on placebo.
• Serious side effects were rare, at 3.7% on CBDV against 1.2% on placebo.
• Liver enzymes rose in three people on CBDV, two of whom stopped treatment, and in one person on placebo, though none met the criteria for serious drug-induced liver injury.

CBDV has also fallen short for pain. In a placebo-controlled crossover trial of 32 people with HIV-related nerve pain, posted as a preprint in 2019, CBDV at 400 mg a day was safe but failed to reduce neuropathic pain intensity.

The unexamined day is a wasted opportunity. Reflect on what you did, what you learned, and how you can improve.

John Dewey

Autism studies and a trial still running

Autism research on CBDV is at an earlier stage. Animal work looks encouraging. In rats exposed to valproic acid before birth, a lab model of autism-like behavior, CBDV given to rats that already showed symptoms restored social behavior, interest in unfamiliar rats and short-term memory, with 20 mg per kilogram working best, while an earlier preventive course did not affect repetitive behaviors. GW Research, which developed CBDV as a drug, funded the study.

The human data are thinner. In a 2021 single-dose study, 28 men, 13 of them autistic, took 600 mg of CBDV and a matched placebo on separate visits while researchers scanned their brains. In the autistic group, CBDV reduced hyperconnectivity to the neurotypical level in circuits of the striatum, a deep brain region. The study did not measure symptoms, and the authors called it preliminary proof of concept.

The trial families are waiting for is still running. A placebo-controlled trial at Montefiore Medical Center in New York aims to study the efficacy and safety of cannabidivarin in about 100 children and teens aged 5 to 18 with autism, at 10 mg per kilogram of body weight a day for 12 weeks, with irritability as the main outcome. Its registry record lists it as recruiting, with primary completion estimated for February 2027.

A smaller trial in Prader-Willi syndrome, a genetic condition, was stopped after six participants because of limited funding, and its main irritability scores ended up nearly identical in both groups. A 2026 systematic review of cannabinoid products in children and teens with autism, Fragile X syndrome and Rett syndrome concluded that current evidence is insufficient to support routine clinical use. So far, claims about CBDV benefits for autism rest on animal studies and brain scans, not on symptom trials.

Hemp products, labels and the law

Hemp products that list CBDV deserve caution. In a 2024 study of 202 CBD products, 74% deviated from their label claim of CBD potency by at least 10%, and CBDV turned up in 37% of the products. The study was funded by Jazz Pharmaceuticals.

Federal hemp law is changing too. The law signed in November 2025 rewrites the hemp definition to exclude products with cannabinoids synthesized or manufactured outside the plant, which would cover lab-made CBDV, and caps final products at 0.4 mg of total THC and similar cannabinoids per container. Most of the new definition was delayed until December 11, 2026, and as of September 28, the FDA had not published its list of cannabinoids with THC-like effects.

In our experience, a CBDV product worth a second look shows:

• A batch lab report that lists CBDV in milligrams
• Total THC per container on the label
• Hemp named as the source, not a lab-made isolate
• No promise to treat autism, seizures or any other condition

Lab promise and human results

CBDV is a non-intoxicating, shorter-tailed cousin of CBD that works against seizures in mice and rats, yet in the largest human trial it did no better than placebo for focal seizures. In autism, a single dose shifted brain connectivity, and the pediatric trial that could show real benefit is still recruiting. Until it reports, CBDV benefits remain a research question, and labels on CBDV products deserve the same skepticism as any other hemp claim.

Barney's Farm has been developing premium cannabis genetics since the 1980s, with over 40 Cannabis Cup wins. Explore our full seed catalog and find strains bred for every climate and skill level.