An Updated Analysis of Clinical Outcome Measures Across Patients From the UK Medical Cannabis Registry.

Introduction

There is a growing body of literature supporting the efficacy of cannabis-based medicinal products (CBMPs). Despite an increase in prescribing globally, there is a paucity of high-quality clinical data on the efficacy of CBMPs for many conditions. This study aims to detail the changes in health-related quality of life (HRQoL) and associated clinical safety in patients prescribed CBMPs for any clinical indication from the UK Medical Cannabis Registry (UKMCR).

Methods

An uncontrolled prospective case series of the UKMCR was analyzed. Primary outcomes included change from baseline in patient-reported outcome measures collected across all patients (the Generalized Anxiety Disorder Scale [GAD-7], EQ-5D-5L, and Sleep Quality Scale [SQS]) at 1, 3, and 6 months. Secondary outcomes included the self-reported incidence and severity of adverse events. Statistical significance was defined as p<0.050.

Results

Three hundred twelve patients were included in the final analysis, with a mean age of 44.8. The most common primary diagnoses were chronic pain of undefined etiology (n=102, 32.7%), neuropathic pain (n=43, 13.8%), and fibromyalgia (n=31, 9.9%). Before enrolment, 112 (35.9%) patients consumed cannabis daily. The median cannabidiol and (-)-trans-Δ9-tetrahydrocannabinol doses prescribed at baseline were 20.0 mg (0.0-510.0 mg) and 3.0 mg (0.0-660.0 mg), respectively. Statistically significant improvements were observed in GAD-7, EQ-5D-5L Index, EQ-5D Visual Analog Scale and SQS scores at 1, 3, and 6 months (p<0.050). There were 94 (30.1%) reported adverse events, of which nausea (n=12, 3.8%), dry mouth (n=10, 3.2%), dizziness (n=7, 2.2%), and somnolence (n=7, 2.2%) were the most common.

Conclusion

This study demonstrated CBMP treatment to be associated with a relatively low incidence of severe adverse events in the medium-term. Positive changes following treatment were observed in general, as well as anxiety and sleep-specific, HRQoL outcomes. Randomized controlled trials are still awaited to assess causation; however, real-world evidence can help inform current clinical practice, future trials, and is an important component of pharmacovigilance.