INVESTIGATOR: Mark Wallace, M.D.
STUDY LOCATION: University of California, San Diego
PROJECT TITLE: Analgesic Efficacy of Smoked Cannabis in Refractory Cancer Pain
PROJECT TYPE: Clinical Study
Recruitment for this study was difficult. Typical methods for recruitment, including posters, newspaper advertisements, and community referral were unsuccessful. Very few cancer pain patients were being seen in the UCSD Pain Clinic during this recruitment period. Local hospice agencies were willing to refer potential subjects, however, these subjects were often already smoking cannabis for pain control. To avoid potential complications from off-study cannabis use, these participants were not recruited. Only one subject was enrolled in the study, and was withdrawn for non-compliance with study procedures. No unexpected or unusual adverse events were noted in this subject.
Pain is one of the most prevalent symptoms among patients with advanced cancer. In spite of this broad clinical and social importance, the development of major therapeutic approaches to the management of cancer pain have been limited to a few therapeutic modalities, notably opiates and nonsteroidal anti-inflammatory drugs (NSAIDs), and to a lesser degree, anticonvulsants. Importantly, recent findings in the molecular biology and the pharmacology of pain transmission have shed light on mechanisms of nociceptive processing and the activity of a variety of "novel therapeutic" modalities, which include the cannabinoids. There are few studies on the efficacy and safety of the cannibinoids in severe refractory pain secondary to cancer. Because severe cancer pain is so resistant to many drug therapies and because the only alternative for these patients is more invasive therapies or heavy sedation, there is a need for more studies on alternative drugs. This proposal describes a double blind crossover clinical trial on smoked cannabis for the treatment of severe cancer pain that is resistant to conventional opioid therapy. The primary outcome of this proposal is the effect of smoked cannabis on the spontaneous pain, mood, function and quality of life of patients with severe refractory cancer pain. The secondary outcome of the proposal is the safety, tolerability, and therapeutic blood concentration of smoked cannabis in the treatment of severe refractory cancer pain.