Therapeutic Response of Cannabidiol in Rheumatoid Arthritis

INVESTIGATORS: Veena Ranganath, MD

STUDY LOCATION: University of California, Los Angeles

PROJECT TITLE: Therapeutic Response of Cannabidiol in Rheumatoid Arthritis

FUNDING SOURCE: Center for Medicinal Cannabis Research

PROJECT TYPE: Clinical Study

STATUS: Enrollment Pending

ABSTRACT:

Rheumatoid Arthritis (RA) is a rare autoimmune destructive arthritic disease, where patients suffer from joint pain, joint deformity, stiffness, swelling, fatigue, impaired function, and decreased quality of life. Presently, there is no cure for RA and up to 70% of RA patients are not in remission. An estimated 64 million Americans have tried cannabidiol (CBD) per 2019 Consumer Reports national survey, where 24% are taking CBD for joint pain. Preclinical data suggests a therapeutic pain effect through anti-inflammatory pathways. However, there are few studies in rheumatic diseases evaluating cannabis-related therapeutic agents, let alone CBD without delta-9-tetrahydrocannabinol (THC). Only one clinical trial with THC+CBD in RA exists with encouraging results, suggesting improvement in pain and RA disease activity. This was a short duration, non-blinded, low dose trial using nabixomol. It is unclear if the therapeutic effects were due the THC, CBD, or combination. In addition, the results were vague in discerning if nabixomol improved pain only, joint inflammation, or both.

We propose to randomize 45 RA patients on stable RA therapy with moderate to severe disease activity and evidence of musculoskeletal ultrasound (MSUS) joint inflammation, to either placebo, CBD 200mg BID, or CBD 400mg BID for 12 weeks. We hypothesize that relative to baseline, CBD will dose-dependently improve RA joint inflammation as measured by disease activity score (DAS28, a validated clinical RA outcome) and MSUS. In addition, we will evaluate if there are any biologic effects of CBD through cytokine array and immune cell sub-types. Lastly, we will evaluate for treatment emergent adverse events and tolerability during the course of the trial.
 
The overall goal of this proof-of-principle proposal is to examine the efficacy and safety of CBD treatment as adjunctive to the medical management of RA patients with moderate to severe disease activity. Our proposal has added value due to our expertise in musculoskeletal ultrasound as a supplementary endpoint beyond the DAS28. The results of this study will inform a future larger clinical trial to apprise the public and physicians on whether CBD truly reduces RA synovial inflammation and provide evidence-based CBD dosing.