Distal sensory polyneuropathy is the most common neurological complication of HIV disease and its treatment. To date no standard effective therapy has been identified.~In this study, scientists will evaluate the effectiveness of treating HIV-associated neuropathy with methadone alone and in combination with a novel cannabinoid SAB378. A cannabinoid is a molecule found only in the Cannabis plant. Cannabis and some cannabinoids are effective analgesics or pain relievers. The rationale for combination therapy is twofold: (1) medications with unique mechanisms of action may affect different aspects of neuropathic pain and (2) combination therapy may act synergistically-meaning the combined effect may be greater than the effect of each drug alone.~Approximately 84 participants will be enrolled in this double-blind, placebo-controlled, crossover study. Participants will be randomly assigned to three treatment groups-those receiving methadone and SAB378 placebo (an inactive substance), those receiving methadone and active SAB378, or those receiving methadone placebo and SAB378 placebo. All participants will be exposed to each of the 3 treatment groups during the study.~This trial is part of the Neurologic AIDS Research Consortium, an effective collaborative clinical study group dedicated to the study of HIV-associated neurological disease.
The purpose of this study is to evaluate the effectiveness of methadone alone and in combination with SAB378 for the treatment of painful HIV-associated neuropathy.