Researchers in the U.K. are planning clinical trials that may give new hope to sufferers of Parkinson’s and their families.

The trials will examine the effects of cannabidiol (CBD), a psychoactive but non-intoxicating compound derived from the cannabis plant, on Parkinson’s-related psychosis, which can include terrifying symptoms such as delusions and hallucinations.

The small preliminary study, which is to be led by King’s College London and will be funded by Parkinson’s U.K., is set to begin in 2020.

The trial will be composed of two parts. After establishing the most effective dose of the cannabinoid in the first stage (up to 1,000 mg of CBD), 120 patients will be recruited for the second stage, with 60 patients being administered CBD via capsule and 60 receiving a placebo.

King’s College scientists will then administer numerous tests, including neuroimaging, to assess the potential efficacy of the treatment. The trial will run for 12 weeks.

Parkinson’s U.K. has pledged £1.2 million for the second phase of the trials.

Professor of neuroscience and psychiatry Dr. Sagnik Bhattacharyya and clinical researcher Dr. Latha Velayudhan will lead the study.

“The study will also look at the effect of CBD on other symptoms, which will pave the way for scientists to investigate the potential of the compound in treating these in future studies,” Dr. Bhattacharyya stated. “We hope this will progress to large-scale clinical trials—the final step towards becoming a new treatment that will improve the lives of people with Parkinson’s,” he added.

Parkinson’s U.K. director of research Dr. Arthur Roach concurred. “There are many unanswered questions about the value of CBD for people with Parkinson’s,” Dr. Roach said in a news release.

“But this trial will help us to determine whether it can help with the debilitating symptoms of hallucinations and delusions. If successful, this trial could result in people with Parkinson’s being able to access a regulated medicine, rather than reverting to expensive unregulated supplements that haven’t been monitored for their effectiveness,” he said.