Reduction of apathy and caregiver distress using a combination of tetrahydrocannabinol and melatonin in dementia due to Alzheimer’s disease

Background Apathy is one of the most frequent and long‐lasting neuropsychiatric symptoms (NPS) in Alzheimer’s disease (AD). Up to 78% of AD patients exhibit apathy, which is related to caregiver distress, decreased quality of life, and increased morbidity. While many medications and behavioral interventions are used to treat apathy, the effects are often limited and lack in‐depth research to support these approaches. We present preliminary data for improvement in NPI‐apathy (NPI‐ap) scores and NPI Caregiver Distress (NPI‐D) scores using IGC‐AD1, a tetrahydrocannabinol (THC) and melatonin combination. Method Twelve patients with mild (15.38%) to moderate (84.6%) AD (NIA‐criteria, 10‐active, 2‐placebo, 81.5±5.5yrs, 69.2% women) participated in a three Cohort, Phase‐1, MAD, safety and tolerability trial (IND146069, NCT04749563). In Cohort‐1, IGC‐AD1 was administered QD at 1ml for 14‐days (EOT). In Cohorts‐2 and 3, one ml BID and TID were administered respectively, with a minimum of 4‐days washout between Cohorts. Solicited and non‐solicited adverse events (AEs) were monitored daily. In each Cohort, seven participants (5‐active, 2‐placebo) had apathy at baseline, as rated by the NPI‐ap. They were administered the NPI‐ap at EOT and the Wilcoxon matched pairs signed‐rank test (R‐Studio, dplyr) was used to compare the difference in NPI‐ap scores between baseline and EOT. A similar analysis was carried out for NPI‐D. Result In Cohort‐1 mean NPI‐ap at baseline and EOT was 5.4 and 3 respectively (mean difference = ‐2.4, v = 6, p = 0.091). In Cohort‐2 mean NPI‐ap at baseline and EOT was 5.2 and 2.4 respectively (mean difference = ‐2.8, v = 6, p = 0.087). In Cohort‐3 mean NPI‐ap at baseline and EOT was 5.2 and 2.6 respectively (mean difference = ‐2.6, v = 6, p = 0.087). Results for NPI‐D: (Cohort‐1:mean difference = ‐0.6, 37.5%, v = 6, p = 0.075; Cohort‐2:mean difference = ‐1.8, 69.2%, v = 15, p = 0.028; Cohort‐3:mean difference = ‐0.2, 12.5%, v = 2, p = 0.5). No serious AEs, no deaths, and no dropouts due to AEs were reported. No major changes in concomitant medications were observed. Conclusion As IGC‐AD1 contains THC, the results are intriguing because cannabis use has been associated with apathy but also increased empathy and sociality. In Cohort‐1, Cohort‐2, and Cohort‐3 NPI‐ap was reduced 44.44%, 53.85%, and 50% respectively. These results, while not statistically significant (p>0.05), appear clinically significant (reduction≥30%). A larger placebo‐controlled st