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Found 1 Presentation For Request "1852P"

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1852P - Chronic cannabis used by patients with advanced cancer during Immunotherapy initiation: clinical outcomes and endocannabinoid levels evaluation

Presentation Number
  • Gil Bar-Sela (Afula, Israel)



Therapeutic use of medical cannabis among cancer patients has become highly prevalent, while its overall effects on the immune system are unclear. This study aims to determine if cannabis consumption during immunotherapy affects therapy outcome for patients with advanced malignancies.


The study was conducted at single Oncology center, in Israel between 01 Sep 2016 and 25 Sep 2018; included 102 [68 immunotherapy alone (I-G) and 34 immunotherapy plus cannabis (IC-G)] consecutive patients with advanced cancers who initiated one of the checkpoint inhibitors. Blood samples were taken before immunotherapy treatment. Endocannabinoid (eCB) levels from various lipid families, were evaluated in a subgroup of 36 patients. Safety and effectivity of cannabis treatment in advanced cancers commencing treatment with immune checkpoint blockers was evaluated with time to tumor progression (TTP) used as a post hoc primary endpoint and overall survival (OS) and eCB concentrations as secondary endpoints with a minimum follow-up time of 7 months.


Kaplan Maier curve showed a significant difference in TTP [I-G 13.1m (95%CI 6.0-NAm) vs. IC-G 3.4m (95%CI 1.8-6.0m), p=0.0025] and OS [IG 28.5m (95%CI 15.6-NAm) vs. IC-G 6.4m (95%CI 3.2-9.7m), p=0.0009]. After adjusting for the line of treatment, Cox regression analysis showed that cannabis consumption decreases OS (HR= 2.18, 95%CI 1.241-3.819. p=0.007) and TTP (HR= 1.95, 95%CI 1.17-3.26. p=0.011). The use of cannabis reduced grade ≥2 immune-related adverse events (iAE) (I-G 39% vs. IC-G 21%, p=0.057). Further analysis of baseline levels of circulating eCB from various lipid families showed no significant changes in their overall concentrations. However, analyzing a cohort comparing patients with progressive disease to those with complete remission correlates baseline eCB levels and expected OS, suggesting that the eCB system may play a role in immunotherapy outcomes.


Initiating immunotherapy with cannabis use negatively affects OS and TTP of cancer patients treated with immunotherapy.

Clinical trial identification

Prospective observational study- not registries in the NIH. Israel IRB Certification 0089-16-RMB.

Legal entity responsible for the study

The authors.


Has not received any funding.


All authors have declared no conflicts of interest.