Dose Response Relationship of Medical Cannabis and Symptom Control in Patients With Pancreatic Cancer: An Analysis of the CANPAN Trial.

BACKGROUND: In a pilot waitlist-control randomized trial, a personalized medical cannabis intervention improved certain symptoms among patients with pancreatic cancer over 8 weeks. Longer-term and dose-response data can guide future trial design. METHODS: CANPAN enrolled 32 cannabis-naïve patients with newly diagnosed locally advanced/metastatic pancreatic adenocarcinoma (NCT06605430). Patients were randomized to early (0-8 weeks) or delayed (9-16 weeks) cannabis intervention. Primary efficacy results over the first 8 weeks were previously reported. We investigated cannabis use and patient-reported outcome (PRO) completion over 9-16 weeks, and the relationship between tetrahydrocannabinol (THC) dose and symptom efficacy. RESULTS: Among 32 participants, 23 (72%) used cannabis during their assigned 8-week period (12/16 in early arm and 11/16 in delayed arm). Of these, 16 (50%) had both pre-cannabis and 8-week post-cannabis initiation PRO data available. At the end of the 16-week study period, PRO data were available for 16 (50%) participants (9/16 early arm, 7/16 delayed arm). Median daily THC dose 4 weeks after starting cannabis was similar in early vs delayed arms (10 mg vs 9.3 mg). A higher average daily THC dose was associated with improvements in anxiety (r 0.52, p = 0.038) and insomnia (r 0.53, p = 0.033). A ≥ 10 mg daily THC dose (vs < 10 mg) was associated with mean improvement in 4 vs 2.1 symptoms. CONCLUSIONS: The 50% complete data availability at 16 weeks, dose-response relationship with psychological symptoms, and threshold dose for multi-symptom efficacy will guide future trials. Similar cannabis use patterns across arms raise confidence in the waitlist-control design.