Cost-effectiveness of an oral THC: CBD cannabis extract for secondary prevention of refractory, chemotherapy-induced nausea and vomiting.

Abstract

TPS11188 Background: The CannabisCINV trial showed the incorporation of a THC:CBD (tetrahydrocannabinol:cannabidiol) cannabis extract in addition to usual, guideline-recommended antiemetic prophylaxis, reduced the incidence of refractory chemotherapy-induced nausea and vomiting. The aim of this within-trial cost-effectiveness analysis was toassess the incremental costs and benefits of oral THC: CBD versus placebo, for preventing chemotherapy-induced nausea and vomiting. Methods: The analysis was performed from a health system perspective, using prospectively collected data from the CannabisCINV trial and linked Medicare data. The evaluation focused on the costs and benefits associated with oral THC: CBD cannabis extract versus placebo in addition to usual care, on complete response: defined as no emesis and no use of rescue medications during the overall treatment phase (0-120 h, cycle 1). The primary economic outcome was an incremental cost-effectiveness ratio (ICER) of achieving a complete response. One-way sensitivity analyses and non-parametric bootstrapping (with 1,000 replications) were conducted to assess the robustness of results. Results: Of 147 participants randomized, 60 of 73 assigned THC:CBD and 66 of 74 assigned placebo consented to Medicare data linkage. The incidence of complete response was higher for THC:CBD than placebo (24% vs 5%, absolute difference 19%, 95%CI 13 to 26%). The mean cost (AUD) of hospitalisation was $580 (SD $7,831) for the intervention group and $1,873 (SD $7,235) for placebo. The mean healthcare costs (AUD) were $1,464 (SD $4,667) for THC:CBD group and $2,725 (SD $9,237) for the placebo. The THC:CBD group had a mean total healthcare cost saving of $1,261 per patient (95% CI -$3,550 to $1029) compared with the placebo group. THC:CBD was less expensive and more effective than placebo (i.e. dominant), in the primary analysis, and over the range of pre-specified sensitivity analyses. Conclusions: This within-trial analysis indicates oral THC: CBD is cost-effective for the treatment of refractory, chemotherapy-induced nausea and vomiting from a health system perspective and supports reimbursement in this setting. The trial and economic evaluation were prospectively registered in the Australian and New Zealand. Clinical trial information: ACTRN12616001036404.