Cannabinoids for Osteoarthritis Pain Effectiveness Trial

Summary

This study aims to investigate whether oral cannabis extracts can effectively manage pain caused by osteoarthritis (OA), a common joint condition affecting one in seven Canadians. Current OA treatments often have limited effectiveness and may cause side effects. As a result, many individuals with OA turn to medical cannabis for pain relief, despite limited scientific evidence supporting its efficacy.

The goal of this study is to assess the feasibility of a larger trial evaluating the effects of two cannabis compounds-CBD and THC-compared to a placebo (a look-alike substance containing no active drug) on pain interference in patients with hip and/or knee osteoarthritis.

Participants will:

* Take either CBD, THC, or a placebo capsule daily for 8 weeks
* Complete follow-ups remotely, with no in-person clinic visits required
* Maintain a diary tracking their study drug usage and any additional pain medications

Conditions

• Osteoarthritis of Knee
• Osteoarthritis Hip

Interventions

DRUG

CBD

The starting dose will be 1 capsule per day (50 mg CBD) taken orally. The dose will be gradually increased over the first four weeks, based on patient assessment, up to a maximum of five capsules per day (250 mg CBD) in divided doses. Once the dose that maximizes potential therapeutic effects while minimizing adverse effects has been determined, it will be maintained for the remaining four weeks of the trial.

DRUG

THC

The starting dose will be 1 capsule per day (3 mg THC) taken orally. The dose will be gradually increased over the first four weeks, based on patient assessment, up to a maximum of five capsules per day (15 mg THC) in divided doses. Once the dose that maximizes potential therapeutic effects while minimizing adverse effects has been determined, it will be maintained for the remaining four weeks of the trial.

DRUG

Placebo

The starting dose will be 1 capsule per day taken orally. The dose will be gradually increased over the first four weeks, based on patient assessment, up to a maximum of five capsules per day in divided doses. Once the dose that maximizes potential therapeutic effects while minimizing adverse effects has been determined, it will be maintained for the remaining four weeks of the trial.

Sponsors & Collaborators

• Canadian Institutes of Health Research (CIHR)

  collaborator OTHER_GOV

• University Health Network, Toronto

  lead OTHER

Principal Investigators

• Dr. Hance Clarke, MD · University Health Network, Toronto

Study Design

Allocation

RANDOMIZED

Purpose

OTHER

Masking

QUADRUPLE

Model

PARALLEL

Eligibility

Min Age

40 Years

Max Age

80 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2026-01-29

Primary Completion

2026-12-31

Completion

2027-02-28

Countries

• Canada

Study Locations