Abstract
BACKGROUND: A full understanding of the economic burden associated with treatment-related adverse events (AEs) can aid estimates of the incremental costs associated with incorporating new technologies and support cost-effective economic modeling in Brazil. In this context, the main objective of this work was to evaluate in a real-life database: (i) the direct medical cost of monitoring the occurrence of AEs (CMO); (ii) the direct medical cost of managing an identified AE (CMN); and (iii) the total direct medical cost of monitoring and managing AEs (TMC), in quarterly periods from 0 to 24 months of the monitoring of cancer patients who used a PD-1 inhibitor from the perspective of the supplementary health system in Brazil. METHODS: This study was conducted from the supplementary health system (SSS) perspective and followed the methodological guidelines related to cost-of-illness studies. A bottom-up (person-based) approach was used to assess the use of health resources to monitor and manage AEs during the use of PD-1 inhibitors, which made it possible to capture differences in the mean frequency of the use of health services with stratification results for different subgroups. As the Brazilian SSS is complex, asymmetric, and fragmented, this study used information from different sources. The methodology was divided into three parts: (i) Data Source: clinical management of AEs; (ii) Microcosting: management of the economic burden of AEs; (iii) Statistical analysis: stratification of results for different subgroups. RESULTS: Analysis of the economic burden of toxicity showed higher CMO costs than CMN in all the periods analyzed. In general, for every BRL 100 on average invested in the TMC of AEs, BRL 95 are used to monitor the occurrence of the AE and only BRL 5 to manage an identified AE. This work also showed that the sociodemographic characteristics of patients, the journey of oncological treatment, and the toxicity profile affect the economic burden related to AE. CONCLUSION: This study provided real-world evidence of the economic burden of AEs associated with the use of PD-1 inhibitors in Brazil. This work also made methodological contributions by evaluating the economic burden of AE of PD-1 inhibitors considering the kinetics of toxicity occurrence and categorizing the costs in terms of CMO, CMN and TMC.