Resource utilization and costs of managing severe adverse events associated with chemotherapy and immunotherapy in lung cancer: a consensus-based microcosting study in Jordan

To estimate the direct medical costs of managing panel‑selected Grade III/IV adverse events that were considered most relevant to the Jordanian clinical setting associated with chemo-immunotherapy regimens in lung cancer patients from the Jordanian healthcare provider perspective and to identify the principal cost drivers. A microcosting approach was employed, utilizing consensus-based management protocols derived through a two-round modified Delphi process in Jordan. Fourteen Grade III/IV adverse events were evaluated. Episode costs were estimated from adverse-event detection to acute clinical resolution in 6 months where applicable or 6 months of treatment for chronic adverse events, using multiple Jordanian cost sources. One-way deterministic sensitivity analysis was performed. No discount rate was applied due to the costing of one episode less than a year duration. Base-case episode costs ranged from $55.06 for maculopapular rash to $5118.17 for pneumonitis. The five most costly adverse events per episode were pneumonitis ($5118.17), myocarditis ($3872.05), diarrhea and colitis ($3008.23), febrile neutropenia ($2,876.81), and thrombocytopenia ($2867.94). Hospitalization was the dominant cost driver, accounting for 47.4% of mean episode costs across all adverse events. These consensus-derived unit cost estimates provide critical inputs for future cost-effectiveness analyses of lung cancer systemic therapies in Jordan.