Tolerability and Efficacy of a 10:25 Preparation of Δ9-Tetrahydrocannabinol and Cannabidiol for Treatment of Chronic Back or Neck Pain: A Multiple-Dose Escalation Study.

INTRODUCTION

The aim was to demonstrate the safety and tolerability of cannabidiol (CBD) with Δ9-THC in patients with moderate to severe chronic back or neck pain unresponsive to over-the-counter non-opioid analgesics.

METHODS

This was a non-randomized, single-arm, open-label study. Participants received escalating doses of an oromucosal-administered combination containing 10 mg/mL of Δ9-THC, 25 mg/mL of CBD. On day 1, patients received once-daily 0.5 mL Cybis 10:25 (5 mg Δ9-THC plus 12.5 mg CBD daily), escalated at days 8, 15, and 22 to 0.5 mL twice-daily (bd) (10 mg Δ9-THC plus 25 mg CBD daily), 1.0 mL bd (20 mg Δ9-THC plus 50 mg CBD daily), and 1.5 mL bd (30 mg Δ9-THC plus 75 mg CBD daily), respectively. The primary outcome was safety and tolerability, with secondary objectives including pharmacokinetic and efficacy outcomes.

RESULTS

28 patients were enrolled in the study. Their median age was 63.3 years, and half were female. The median history of neck/back pain was 10 years. The pharmacokinetics following single doses of 0.5 mL were variable; however, there were dose-dependent increases in trough levels of CBD and Δ9-THC. Cybis 10:25 was well tolerated, with the majority of adverse events of mild severity. The most common adverse events were nausea, vomiting, fatigue, dizziness, headache, paresthesia, and anxiety. There were dose-dependent improvements in numerical pain rating scores ( < 0.001), with clinically significant reductions in pain at 1.0 mL bd and 1.5 mL bd doses (28.8% and 34.1% reductions, respectively, < 0.001). Depressive symptoms and stress had dose-dependent reductions ( = 0.0182, < 0.01, respectively).

CONCLUSION

In patients with chronic neck/back pain, CBD and Δ9-THC are well tolerated and doses of 1.0 mL bd and 1.5 mL bd showed clinically significant reductions in pain compared to baseline pain scores.