Clinical Trial: THC-CBD Formulation Reduces Agitation in Dementia Patients, With Nearly 90% Showing Improvement

Nearly 90% of dementia patients who received a specially formulated combination of THC and CBD showed behavioral improvement after 12 weeks, according to results from a first-of-its-kind clinical trial.

The findings come from the LiBBY trial, a multicenter Phase II study involving 120 hospice-eligible patients with Alzheimer’s disease or another form of dementia who were experiencing agitation. Participants had an average age of 80.

The results are being presented July 14 at the Alzheimer’s Association International Conference in London by Dr. Jacobo Mintzer of the Medical University of South Carolina and Brigid Reynolds of Georgetown University.

Participants were randomly assigned to receive either a placebo or purified THC and CBD delivered orally through a rapid-acting oil formulation. The study was double-blind, meaning participants, caregivers and clinicians did not know who received the active medication.

After two weeks, those receiving THC and CBD had a 6.27-point greater reduction in average agitation scores than the placebo group. The reduction remained significant after 12 weeks.

Using a separate measure of overall behavioral change, researchers found that 83.9% of patients in the THC-CBD group improved after two weeks, compared with 30.5% of those given a placebo. At 12 weeks, the rates were 87.2% and 23.6%, respectively.

Agitation in people with advanced dementia can include restlessness, aggression and emotional distress, creating challenges for both patients and caregivers. Existing medications used to manage the symptoms can have limited effectiveness and may cause significant side effects.

Researchers evaluated agitation using the Cohen-Mansfield Agitation Inventory, which measures the frequency of 29 behaviors. Caregivers completed the assessments and administered the medication during the trial.

“These trial results were extremely impressive and showed a level of response not seen before in clinical trials related to dementia,” Mintzer said. “Rarely do we see close to 90% of patients in a trial respond positively to a new medication.”

Adverse events were reported among 46.7% of participants receiving THC and CBD and 42.4% of those receiving a placebo. The events, which included infections and gastrointestinal conditions, were considered common for the patient population.

The study was conducted through 10 medical centers, with visits taking place in participants’ homes or residential facilities.

Researchers emphasized that the medication tested in the trial was a standardized pharmaceutical formulation and should not be considered interchangeable with THC or CBD products sold at marijuana dispensaries or online.

Commercial products can vary considerably in potency, composition and quality, Reynolds said, whereas the trial medication was manufactured and administered under medical supervision.