Clinical outcome data of first cohort of chronic pain patients treated with cannabis-based sublingual oils in the United Kingdom – analysis from the UK Medical Cannabis Registry

Michal Kawka, Simon Erridge, Carl Holvey, Ross Coomber, Azfer Usmani, Mohammad Sajad, Michael W Platt, James J Rucker, Mikael H Sodergren

Keywords: Cannabinoids, Medical Cannabis, Health-related Quality-of-Life, Chronic Pain.

Background:
The estimated global incidence of chronic pain is 20%, with the burden expect to rise further as the global population ages. Whilst pharmaceutical management of chronic pain is increasingly limited in primary care, Cannabis-based medicinal products (CBMPs) represent an emerging therapeutic option in the management of chronic pain. Despite promising pre-clinical data, there is a paucity of high-quality evidence to support the routine use of CBMPs for chronic pain.

Research questions:
This study aimed to investigate the health-related quality of life outcomes of patients with chronic pain who were prescribed CBMP oil preparations.

Method:
A case-series comprised of patients from the UK Medical Cannabis Registry, who were treated with CBMP oils (Adven®, Emmac Life Sciences Group) for a primary indication of chronic pain was performed. The primary outcomes were the changes in Brief Pain Inventory short-form (BPI), Short-form McGill Pain Questionnaire-2 (SF-MPQ-2), Visual Analogue Scale (VAS) Pain, General Anxiety Disorder-7 (GAD-7), Sleep Quality Scale (SQS), and EQ-5D-5L PROMs, at 1, 3, and 6 months.

Results:
110 patients were included, with the majority having a diagnosis of chronic non-cancer pain (n=53, 48.2%). Significant improvements in SQS, EQ-5D-5L pain and discomfort subscale, and Brief Pain Inventory Interference Subscale (p<0.050) at 1, 3, and 6 months were demonstrated. There were no notable differences between cannabis naïve and previous cannabis users in terms of quality-of-life outcomes. The adverse event incidence was 30.0%, with most (n=58, 92.1%) adverse events being either mild or moderate in intensity.

Conclusions:
Treatment of chronic pain with CBMP oils was associated with an improvement in pain-specific outcomes in addition to HRQoL and self-reported sleep quality. Similarly, relative safety was demonstrated over medium-term prescribed use. Whilst these findings must be treated with caution considering the limitations of study design, this provides a platform to inform future clinical trials.

Points for discussion:
How do CBMPs fit into the current paradigm for chronic pain treatment?

Are CBMPs an acceptable treatment for medical practitioners and patients?

Is RWE sufficient to inform regulatory guidance and individual clinical care with CBMPs?