Chronic low back pain is a significant global health issue. For individuals requiring long-term treatment, the medical consensus highlights a continuing need for new options. This need is particularly acute given the challenges associated with common long-term pharmacological treatments.
A recent phase 3 study reported the outcomes of full-spectrum cannabis extract, VER-01, a novel, standardised full-spectrum Cannabis sativa extract, when compared to placebo in a double blind randomised controlled trial for chronic low back pain. This provided robust evidence supporting the efficacy and safety profile of VER-01 in the treatment of chronic low back pain.
A subsequent phase 3 trial, published in Pain Therapy, directly compared VER-01 against a range of prescribed opioid analgesics in 384 adults with CLBP. The trial was specifically designed to gather specific data on gastrointestinal tolerability and reported pain symptom over six months.
Design of the Trial
This was a pragmatic, multicentre, open-label, randomised, controlled trial, conducted at 41 outpatient sites and hospitals across Europe. The study compared two treatment approaches over a six-month period:
- VER-01: A standardised full-spectrum extract derived from the Cannabis sativa DKJ127 strain. Each single dose unit contains 2.5 mg tetrahydrocannabinol (THC), 0.1 mg cannabigerol and 0.02 mg cannabidiol, in a sesame oil excipient. VER-01 also contains other bioactive compounds, including terpenes, with β-caryophyllene and α-bisabolol as the primary components. During the treatment phase, the maximum daily dose was limited to 32.5 mg THC. The maximum daily dose of VER-01 peaked at week 5 and was equivalent to 18.83mg THC per day.
- Opioids: Participants in this arm received one of a range of commercially available oral or transdermal opioid analgesics (e.g., tramadol, tapentadol, oxycodone). This approach allowed investigators to adjust the opioid choice and dosage throughout the trial, mirroring standard clinical practice. The placebo was formulated to match VER-01’s appearance and sensory characteristics. The initial daily dose of opioids after titration was 26.77mg oral morphine equivalents. The maximum daily dose (31.64mg oral morphine equivalents) was observed at 25 weeks.
The trial included:
- A 2-week run-in phase to assess baseline pain intensity, following which 384 eligible participants were randomly assigned to receive either VER-01 or opioid analgesics.
- A 3-week titration period: 189 participants received VER-01 and 186 participants received opioid analgesics; titration aimed to determine the individual optimal dose.
- A 6-month treatment period: 140 participants in the VER-01 group and 126 in the opioid group completed the treatment regimen.
- A 2-week wash-out period: Participants randomised to opioids received both opioid and rescue medication to taper off opioids, whereas VER-01 was discontinued abruptly.
Key Results
The primary outcome was the relative risk of constipation occurrence after 27 weeks of treatment. Secondary endpoints included changes in pain and sleep scores and physical function.
Participants also completed the Study Medication Withdrawal Questionnaire (SMWQ), and the occurrence of adverse events was recorded to determine the tolerability and safety of study medications.
Key findings from the trial included:
Incidence of Constipation
The trial’s primary measure focused on gastrointestinal tolerability, specifically the risk of developing constipation.
- Incidence of Constipation: The study found that subjects receiving VER-01 were four times less likely to report developing constipation than those receiving opioids.
- Laxative Use: Subjects receiving VER-01 also reported a threefold lower incidence of laxative use.
- Quality of Life Signal: Notably, among participants in the opioid group who developed constipation, quality-of-life measures failed to improve, even though pain relief was achieved.
Symptom Changes Over Six Months
The study collected longitudinal data on pain intensity and sleep quality, both measured using an 11-point Numeric Rating Scale (NRS).
- Pain Severity: Over the entire six-month period, the mean reported pain change was 2.50 NRS points with VER-01 versus 2.16 NRS points with opioids.
- Sleep Quality: The mean change in sleep quality was 2.52 points with VER-01 versus 2.07 points with opioids.
Safety and Treatment Continuation
The overall incidence of treatment-emergent adverse events was comparable between the two groups.
Treatment-emergent serious adverse events were also comparable between VER-01 (4.8%) and opioids (4.3%).
Similar proportions of VER-01 (12.7%) and opioid (13.4%) discontinued treatment due to adverse events.
Conclusions
In conclusion, this Phase 3 study provides robust evidence supporting the efficacy and strong safety profile of VER-01 in the treatment of chronic low back pain. This is a valuable contribution to the evidence base supporting treatment decisions where licensed medicines cannot meet a patient’s clinical needs.
Given the diverse and often complex nature of chronic pain and other conditions, continued research is essential to establish the efficacy and safety of unlicensed medical cannabis products across the heterogeneous category of chronic pain conditions and indeed other indications for unlicensed medical cannabis. By continually expanding this evidence base, we can ensure that future treatment decisions are guided by the highest standards of safety and efficacy.
Disclaimer: This blog post is for informational purposes only and is based on a specific clinical study. The efficacy and safety of medical cannabis depend on both the medication prescribed and the individual. Patients should always consult a qualified healthcare professional before making any decisions about their treatment.
