OBJECTIVES: Immune Checkpoint Inhibitors (ICI) were initially available for advanced/metastatic stages (AMS) of cancer. However, there is a growing trend of making them accessible at earlier stages of cancer (ESOC). The objective of this study was to analyze ICI cost-effectiveness assessment reports (CEAR) conducted by French authorities in AMS and ESOC.

METHODS: A systematic review was conducted on French CEAR and included those related to ICI from February 2014 to June 2023. Identified CEAR were analyzed to determine average incremental costs and average quality-adjusted life year (QALY), incremental cost-effectiveness ratio (ICER), time horizon and type of model according to AMS or ESOC.

RESULTS: Among the 214 CEAR identified, 45 of them met the inclusion criteria. Out of these, 36 were related to AMS (80%) and 9 (20%) were related to ESOC. In AMS, ICI were used as monotherapies in 54% of CEAR or in combination with other treatments in 46% of cases. 89% ESOC CEAR involved ICI as monotherapy. Average additional cost for ICI in AMS was 76,000€, while it was 43,000€ in ESOC. ICI generated an average of 0.69 and 1.12 additional QALY in AMS and ESOC respectively. Mean ICER for ICI in AMS was 130,000€/QALY versus 38,000€/QALY in ESOC. Mean time horizon in AMS was 11 years, while it was 26 years for ESOC. Most models were area under the curve model (94%) for AMS, Markov-like model (89%) for ESOC.

CONCLUSIONS: ICI in ESOC showed a nearly two-fold reduction of additional costs compared to AMS, which is explained by limited treatment duration (1-year maximum stopping rule), potential avoidance or delay of more expensive subsequent treatments and monotherapy use in ESOC. ICI in ESOC demonstrated a higher gain in QALY compared to AMS that might be attributed to a longer time horizon and due to the cured potential in this setting.