Vaporized Cannabis for Chronic Pain Associated With Sickle Cell Disease

This is a proof-of-principle investigation of the safety and potential effectiveness of inhaled vaporized cannabis when added to a stable analgesic regimen in sickle cell disease (SCD) patients with chronic pain. The study will be comprised of two 5-day intervention periods in the inpatient setting (the Clinical Research Center at SFGH), with completion of a 5-day daily pain diary prior to admission to establish an outpatient baseline. Participants will be randomly assigned, in double-blind fashion, to treatment with (A) vaporized cannabis with an approximately 1:1 ration of delta-9-tetrahydrocannabinol:cannabidiol or (B) vaporized placebo. Those who receive treatment A during the first admission will receive treatment B in the second, and those who receive treatment B during the first admission will receive treatment A in the second. The two admissions will be spaced at least 14 days apart. On Day 1 of each admission, subjects will provide blood samples for baseline markers of inflammation and SCD disease progression. They will undergo assessments of pain, mood, and quality of life. At 12 pm on Day 1, they will inhale vaporized study agent (equivalent to 1 cannabis/placebo cigarette) using the Volcano® vaporizer; on Days 2-4 they will inhale study agent at 8 am, 2 pm, and 8 pm, and they will inhale their final dose on Day 5 at 8 am. Subjects will continue their pre-study analgesic regimen while in the study. If additional analgesia is required, supplemental therapy will be administered and the dose recorded. Pain measurements by visual analogue scale will be obtained every 2 hours while subjects are awake. On Day 5 a second set of blood samples for inflammation markers and disease progression will be obtained, and subjects will again complete pain, mood, and quality of life assessments.