Phase 3 Trial: Full-Spectrum Cannabis Extract Significantly Reduces Chronic Low Back Pain | Research

The takeaway

A phase 3 RCT of 820 adults found full-spectrum cannabis extract VER-01 significantly reduced chronic low back pain compared to placebo, with sustained effects over 12 months and no signs of dependence.

Chronic pain patients, pain management clinicians, cannabis medicine researchers

820-person phase 3 RCT published in Nature Medicine

What the researchers found

VER-01 met its primary endpoint with a mean pain reduction of 1.9 NRS points (vs. placebo difference of -0.6 points, p < 0.001) over 12 weeks. Pain continued decreasing to -2.9 points during the 6-month open-label extension. For neuropathic pain, NPSI scores decreased by 14.4 points (vs. placebo difference of -7.3, p = 0.017). No signs of dependence or withdrawal were observed.

Why it matters

This is one of the largest and most rigorous RCTs of a cannabis-based medicine for chronic pain to date, published in a top-tier journal. Chronic low back pain affects over half a billion people globally, and current medications carry substantial risks.

The numbers in context

820 participants; -1.9 NRS point pain reduction (placebo difference -0.6, p < 0.001); -2.9 NRS points at 6-month extension; NPSI improvement -14.4 points (placebo difference -7.3, p = 0.017); adverse events 83.3% vs. 67.3% for placebo.

How the study worked

Multicenter, randomized, placebo-controlled phase 3 trial with 820 adults with chronic low back pain. Included a 12-week double-blind phase, 6-month open-label extension, and randomized withdrawal phase. Published in Nature Medicine.

What this study cannot tell us

Higher adverse event rate (83.3% vs. 67.3%), though events were mostly mild and transient. The randomized withdrawal phase did not meet its primary endpoint on time to treatment failure. Open-label extension phases lack placebo control.

How to read the evidence

Large, multicenter, randomized, placebo-controlled phase 3 trial published in Nature Medicine with pre-registered endpoints.

When this study was published

2025 publication

The bigger picture

If confirmed by further trials, this could shift the conversation about cannabis for chronic pain from anecdotal reports and small studies to evidence-based medicine. The absence of dependence signals after extended use addresses one of the key concerns about cannabinoid therapies.

Questions still open

Will regulatory agencies accept this evidence for approval of cannabis-based pain treatments?
How does VER-01 compare directly to existing pain medications in head-to-head trials?

Common questions

Does cannabis work for chronic low back pain?

In this large phase 3 trial, a full-spectrum cannabis extract significantly reduced chronic low back pain compared to placebo, with a 1.9-point reduction on a pain scale that continued improving to 2.9 points over 6 months. However, adverse events were more common with the cannabis treatment.

Does cannabis for chronic pain lead to dependence?

In this 12-month trial of 820 participants, no signs of dependence or withdrawal were observed with the full-spectrum cannabis extract, though longer-term data would be needed for definitive conclusions.

Read the original research

Full-spectrum extract from Cannabis sativa DKJ127 for chronic low back pain: a phase 3 randomized placebo-controlled trial.

Nature medicine, 31(12), 4189-4196

View on PubMed ↗Publisher’s paper ↗

Citation

Karst, Matthias; Meissner, Winfried; Sator, Sabine; Keßler, Jens; Schoder, Volker; Häuser, Winfried. (2025). Full-spectrum extract from Cannabis sativa DKJ127 for chronic low back pain: a phase 3 randomized placebo-controlled trial.. Nature medicine, 31(12), 4189-4196. https://doi.org/10.1038/s41591-025-03977-0