Medical Marijuana: Hype versus Evidence Monica Malec, MD The University of Chicago, Department of Medicine Section of Geriatrics and Palliative Medicine
Objectives Understand the requirements for physician certification for medical cannabis under the Illinois Compassionate Use of Medical Cannabis Pilot program Recognize the potential indications for cannabinoids and the limited literature to support recommendations Counsel your patients on the potential risks and benefits of cannabinoids including medical marijuana
Compassionate Use of Medical Cannabis Pilot Program Signed by the governor 8/2013 Program underway 1/1/2014 First dispensaries open November 16, 2015 ~ 3300 patients certified in the first year Extended to 2020
Accepted Diagnoses Cancer Glaucoma HIV/AIDS Hepatitis C ALS MS Severe Fibromyalgia Crohn s disease Alzheimer s disease Cachexia/Wasting syndrome Muscular Dystrophy Spinal Cord Disease Tarlov Cysts Hydromyelia Arnold-Chiari malformation Syringomyelia Rheumatoid Arthritis Lupus Spinocerebellar Ataxia PTSD Fibrous Dysplasia Spinal Cord Injury Traumatic Brain Injury Parkinson s Tourette s Myoclonus Dystonia RSD Myasthenia Gravis Hydrocephalus Nail-Patella Syndrome Residual Limb Pain Causalgia CRPS Neurofibromatosis Chronic Inflammatory Demyelinating Polyneuropathy Sjogren s syndrome Interstitial Cystitis
Physician Role Physicians fill out a form created by IDPH certifying that the patient has a qualifying medical condition, is under their care for the qualifying medical condition and have conducted an in person examination Physicians do not prescribe cannabis
Physician Risk Illinois Law explicitly protects doctors from punishment. The US Court of Appeals ruled that doctors cannot be punished or investigated solely for recommending medical marijuana, this is protected free speech The US Supreme Court let that decision stand
Physician Risk 9 th circuit court of appeals ruled in August that if no state laws are broken, the DOJ cannot prosecute Physicians in Illinois are under investigation for not following the requirements outlined in the law
Physician s recommending medical marijuana cannot Conduct an exam using telemedicine Have anything to do with a cultivation center or dispensary Help patients obtain marijuana or direct usage
Patients can obtain 2.5oz every 14 days Cost ~$365/oz
The Food, Drug and Cosmetic Act A drug refers to articles intended for use in the diagnosis, cure, mitigation, treatment or prevention of disease and articles intended to affect the structure or any function of the body The FD&C act requires that the FDA scientifically evaluate all new drugs for both safety and efficacy prior to being advertised and sold
Schedule I The drug or other substance has a high potential for abuse The drug or other substance has no currently accepted medical use in treatment in the United States There is a lack of accepted safety for use of the drug under medical supervision
Marijuana was classified as a schedule I drug in 1970 Recently modified to allow testing on human subjects Rejected request to reschedule in August No currently accepted medical use Chemistry isn t known or reproducible No accepted safety profile
This classification stopped research for decades Not all research, just research of potential medical benefit NIDA continued research on deleterious effects Synthetic cannabinoids moved forward Halted the usual process for drug evaluation for safety and efficacy Spurred the current movement of medicine by popular vote with little evidence to guide recommendations
Definitions Cannabis Cannabis sativa Numerous cannabinoids 70 Cannabinoids Chemical compounds that bind cannabinoid receptors Dronabinol- Synthetic THC, FDA indications for AIDS related anorexia/cachexia, CINV CBD- Cannabidiol, component of cannabis, no psychoactive effects Nabilone-Synthetic THC-like, FDA indication for refractory CINV Nabiximols- THC/CBD liquid oral mucosal spray, not available in US, applying for FDA indication for cancer pain
Endocannabinoid System
Pharmacology THC detected immediately in plasma after one puff Peak concentrations occur in 10 minutes Decrease to 60% at 15 minutes Decrease to 20% by 30 minutes Wide variation in inter-individual concentrations achieved
PHARMACOLOGY Oral administration Peak concentrations in 4-6 hours, ½ life 20-30 hours Low bioavailability, 4-20%
Pharmacology Metabolized by cytochrome P450 enzymes Induced in chronic users Clinical significance unknown Decreased gut motility Decreased stomach acidity
Is it really clear that cannabis helps? Debates are usually emotional not fact based Research lagging far behind demand Many anecdotes of marijuana being the only thing that helped, skewed reporting, unsupported claims, and testimonials are abundantly available
Marijuana for Cancer Invitro and invivo studies show multiple antitumor effects, induction of cell death, inhibition of cell growth, inhibition of tumor angiogenesis, invasion and metastasis Induce apoptosis of glioma cells in culture and regression of glioma cells in mice CBD induced apoptosis in breast cancer cell lines CBD and THC may enhance effects of temozolamide in glioblastoma Immunodeficient mice treated with THC show NSCLC tumor regression, immunocompetent mice treated with THC have more rapid tumor growth No trials of marijuana as cancer treatment
Marijuana for CINV No studies of smoked whole marijuana for CINV One study of smoked THC Dronabinol and nabilone more effective than metoclopramide and neuroleptics but less favorable in terms of side effects including sedation, dizziness, dysphoria, hypotesion and anxiety No comparison of 5HT3 or NK1 receptor antagonists
Marijuana for Anorexia/cachexia No studies for smoked whole marijuana THC effective in anorexia cachexia syndrome Dronabinol 5mg daily superior to placebo for appetite enhancement at 6 weeks, persist up to 12 months, no significant weight gain Beal JE, et al. 1995; Beal JE, et al. 1997 Megestrol 800mg superior to dronabinol 2.5mg BID in cancer patients Jatoi A, et al. 2002
Marijuana for IBD Cannabis induces clinical response in patients with Crohn s disease: a prospective, placebo controlled study 21 patients, 11 treatment, 10 placebo BID marijuana cigarettes with 115mg THC Evaluated at 8 weeks and after a 2 week wash out Complete remission in 5 of 11 in cannabis group vs 1 in placebo Clinical response in 10 of 11 vs 4 of 10 Disease rebounded to pretreatment levels after 2 weeks washout Clin Gastroenterol Hepatol.2013 Oct; 11(10)
Marijuana for pain Chronic Neuropathic or Cancer Pain Moderate quality evidence that cannabinoids are beneficial Smoked THC or nabiximols Reduction in pain 30% compared to placebo Abrams,et al. Neurology 2007;68(7):515-521 Whiting, et al. JAMA.2015; 313(24):2456-2473
Marijuana for Pain Spasticity for MS Moderate - quality evidence that cannabinoids are beneficial No difference between type of cannabinoid, ie nabiximols, nabilone, THC/CBD capsules, dronabinol No studies of marijuana included Whiting, et al. JAMA. 2015;313(24):2456-2473
Unintended Benefits Opioid overdose deaths fell in states with legalized medical marijuana and dispensaries Decreased treatment admissions for opioid addiction Reduction in legal prescription of opioids Reduction in self-reported non-medical use of prescription opioids Rand WR-1130 November 2015 JAMA Intern Med. 2014; 174(10)
RISKS No differences in adverse events based on type of cannabinoid Most Common Adverse Events (descending order of risk) Disorientation Dizziness Euphoria Confusion Drowsiness Dry Mouth Somnolence Balance Problems Whiting, et al. JAMA. 2015;313(24):2456-2473
Risks Cardiovascular Tachycardia Increased Cardiac workload Increased carboxyhemoglobin Orthostatic hypotension Aryana A, Williams M. International Journal of Cardiology 2007;118:141-144 4.8 x higher risk of MI in the first hour after smoking cannabis in patients with underlying cardiovascular disease Mittelman MA, et al. Circulation 2001;103(23):2805-2809
Risks Infection Bacterial pneumonia Aspergillus
Risks Impairments in perception, focus, coordination, reaction time, time perception Impairments may persist for 12-24 hours after euphoria Do not drive or operate heavy machinery while using marijuana
There are no reported deaths attributable to marijuana alone About 10% of marijuana users become addicted
Medical marijuana use frequently coincides with recreational marijuana use Tolerance to adverse effects develops quickly in 2-12 days Jones RT, 1981
It is difficult to know how research applies to what the patient will obtain Patients are guided by dispensary personal and google
Summary While there is indication that cannabinoids have potential benefit for symptoms and treatment related to multiple medical conditions, evidence of definitive benefit for marijuana is lacking There is moderate level evidence of benefit for neuropathic pain and spasticity in multiple sclerosis The risks are more well established but in a medical context, significant gaps remain and medical marijuana is likely safer than some treatments, ie opioids