Real-World Impact of Immunotherapy on Survival and Hospital Costs in Advanced/Metastatic Lung Cancer: A Retrospective Analysis From the French Health Data System

OBJECTIVES: While immunotherapies have shown a substantial clinical benefit in clinical trials, there is a need to evaluate their effectiveness in real-world setting. This study aims to compare overall survival and hospital costs in advanced/metastatic lung cancer patients treated or not by front-line immunotherapy.

METHODS: We performed a retrospective analysis using the French Health Data System (SNDS) from 2010 to 2020. Patients first treated by immunotherapy for advanced/metastatic lung cancer between 2017 and 2020 were selected to constitute the cohort IMMUNOLUNG. Two control cohorts of similar patients receiving a first systemic treatment between 2012 and 2016 were built: the cohort METALUNG-SPECIFICITY (ICD-10 codes C77-C79 in diagnoses) and the cohort METALUNG-SENSITIVITY (ICD-10 code C34 in diagnoses, excluding patients operated or receiving stereotactic radiotherapy). Propensity scores were used to match IMMUNOLUNG patients and control patients (for the 2 cohorts respectively). Overall survival (OS) was estimated as the time between initiation of first systemic treatment and death or last reimbursement (censor), hospital costs were measured on the same period.

RESULTS: The IMMUNOLUNG cohort comprised 15,306 patients, the METALUNG-SPECIFICITY cohort 43,590 patients and the METALUNG-SENSITIVITY cohort 52,432 patients. For each control cohort, 15,306 patients were matched to the cohort IMMUNOLUNG. Median OS was 15.1 months [95% CI : 14.4-15.7] in IMMUNOLUNG vs 7.6 months [7.5-7.8] in METALUNG-SPECIFICITY. The average monthly frequency of hospitalizations was similar between the two cohorts, and led to an average of 6.4 [6.3-6.5] vs 8.8 [8.7-8.9] days of hospitalization per month. The average monthly hospitalization cost for the French National health insurance was €8,717 [8,601-8,832] in IMMUNOLUNG vs €3,885 [3,829-3,942] in METALUNG-SPECIFICITY. Results were similar for the cohort META-SENSITIVITY.

CONCLUSIONS: Patients receiving first-line immunotherapy demonstrated a better overall survival at a higher cost than standard historical chemotherapy regimens.