Title : Reduction of chronic neuropathic pain by a THC-CBD combination capsule: ongoing pilot study
Abstract:
Dr Goldstein will initially present a brief clinical pharmacological summary on aspects of delta-9-tetrahydrocannabinol (THC) including the endogenous cannabinoid (CBD) receptor system, mechanism of action, addiction liability, physical dependence, therapeutic uses, and adverse effects – acute and chronic.
Neuropathic pain, a chronic condition resulting from dysfunction of the central and/or peripheral nervous system(s), is often resistant to pharmacologic treatment such as gabapentin, antidepressants, and opioids; these drugs provide only limited relief and produce many intolerable adverse effects, e.g., drowsiness. Cannabinoids, including delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD), interact with the biologic endocannabinoid system to modulate nociceptive transmission and inflammation, suggesting potential benefit for neuropathic pain management.
In regard to chronic neuropathic pain, specific dose-response clinical research is needed to document THC efficacy. Although marijuana has been rescheduled by the federal government from a Schedule I down to a III, data presented herein have been collected under the first classification. Human studies under USA Schedule I cannot be conducted as a standard clinical trial; thus, it needs to be observational, i.e., subjects can select their doses from several options. In this ongoing pilot study led by Dr. Goldstein, daily oral doses of a 1:1 THC-CBD combination capsule were taken by the subject at bedtime. It examines analgesic and psychosocial effects of a balanced 1:1 THC:CBD capsule formulation taken daily at bedtime for four weeks by adults having chronic neuropathic pain lasting two months or longer. Ten subjects aged 25 to 75 years, certified under Pennsylvania’s Medical Marijuana program, have been enrolled to date. Most participants (5) selected 2.5 milligrams daily with weekly titration to 5 mg, then 10 mg, and last to 15 milligrams. The other five subjects selected different dosage sequences. Pain intensity (0–10 numeric scale) and Health-Related Quality of Life (HrQOL) parameters were assessed at start of Week 1 and end of Week 4. Preliminary results show substantial pain reduction and improved HrQOL scores in many measures including physical and social functioning, energy/fatigue, emotional well-being and analgesia. Mild transient drowsiness was reported in one subject. These early findings indicate that a balanced cannabinoid oral formulation may provide increased analgesia and improved quality-of-life benefits for neuropathic pain patients.
A project to determine 1:1 THC-CBD oral (capsule) efficacy on reduction of anxiety is currently being initiated and will be discussed.
