Prevalence of recreational and medical cannabis products in Veterans and their interactions with cancer directed pharmacological treatment.

Abstract

3089 Background: There is proliferation of literature about the medical uses of cannabis products in patients with malignancies. However, research is lacking as to how cannabis use is affecting the efficacy and toxicity of anti-neoplastic regimens It is known that cannabis is metabolized by the cytochrome p450 pathway, the same as many anti-neoplastic agents and thus there are concerns for potential interactions. Methods: We report an observational study to identify cannabis users in veterans receiving anti-neoplastic therapy in the Memphis VA health system, and to then analyzed for potential interactions between cannabis product and the antineoplastic agent/s they were receiving. Data was collected via voluntary surveys. We then reviewed their charts, recorded the anti- neoplastic medications they were receiving, and evaluated for potential interactions with cannabis, based on a literature review of potential interactions. Results: In this study, 132 veterans agreed to participate. 50 of them acknowledged recent use of cannabis products within the last 90 days. Thus, the prevalence of cannabis use amongst those who participated is 37.87%. Demographically, 10% of the cannabis users were female, and 90% were male, with the majority aged 60-65 (range 46-85). Predominantly, patients inhaled cannabis once daily (38%) as opposed to using a different formulation. The patients who admitted cannabis use were primarily on chemotherapy (42%), while 38% were on immunotherapy, 24% were on targeted therapy and 20% were on endocrine therapy. Some were on multiple drugs. Based on this data and a literature search for interactions, we found that a significant number of the patients in our Veteran’s oncology clinic have a potential increase in toxicity or decreased efficacy from their ant-neoplastic therapy due to CYP interactions with cannabis use. Conclusions: In this exploratory study, we discovered a notable prevalence of patients concurrently using cannabis products while on anti-neoplastic treatment. Given that many anti-neoplastic agents undergo metabolism via the CYP450 pathway, our data suggest that a moderate number of patients in our clinic risk less than optimal outcomes due to concurrent cannabis and anti-neoplastic therapy. To delve deeper, we intend to conduct a follow-up study, focusing on specific adverse effects, hospitalizations, and the subsequent need for 2nd and 3rd line treatments in patients using cannabis. A much larger multi-institutional study should be considered to provide statistically relevant data on true outcomes. [Table: see text]