Cost-effectiveness of treating advanced melanoma with tumor-infiltrating lymphocytes based on an international randomized phase 3 clinical trial

Introduction In a multicenter, open-label randomized phase 3 clinical trial conducted in the Netherlands and Denmark, treatment with ex vivo-expanded tumor-infiltrating lymphocytes (TIL-NKI/CCIT) from autologous melanoma tumor compared with ipilimumab improved progression-free survival in patients with unresectable stage IIIC–IV melanoma after failure of first-line or second-line treatment. Based on this trial, we conducted a cost-utility analysis. Methods A Markov decision model was constructed to estimate expected costs (expressed in 2021€) and outcomes (quality-adjusted life years (QALYs)) of TIL-NKI/CCIT versus ipilimumab in the Netherlands. The Danish setting was assessed in a scenario analysis. A modified societal perspective was applied over a lifetime horizon. TIL-NKI/CCIT production costs were estimated via activity-based costing. Through sensitivity analyses, uncertainties and their impact on the incremental cost-effectiveness ratio (ICER) were assessed. Results Mean total undiscounted lifetime benefits were 4.47 life years (LYs) and 3.52 QALYs for TIL-NKI/CCIT and 3.33 LYs and 2.46 QALYs for ipilimumab. Total lifetime undiscounted costs in the Netherlands were €347,168 for TIL-NKI/CCIT (including €67,547 for production costs) compared with €433,634 for ipilimumab. Undiscounted lifetime cost in the Danish scenario were €337,309 and €436,135, respectively. This resulted in a dominant situation for TIL-NKI/CCIT compared with ipilimumab in both countries, meaning incremental QALYs were gained at lower costs. Survival probabilities, and utility in progressive disease affected the ICER most. Conclusion Based on the data of a randomized phase 3 trial, treatment with TIL-NKI/CCIT in patients with unresectable stage IIIC–IV melanoma is cost-effective and cost-saving, both in the current Dutch and Danish setting. These findings led to inclusion of TIL-NKI/CCIT as insured care and treatment guidelines. Publicly funded development of the TIL-NKI/CCIT cell therapy shows realistic promise to further explore development of effective personalized treatment while warranting economic sustainability of healthcare systems.