OBJECTIVES: To analyze the number needed to treat (NNT) and cost of preventing an event (COPE) for cemiplimab and pembrolizumab as first-line treatments for advanced non-small-cell lung cancer with PD-L1 ≥ 50%, under the Brazilian private healthcare perspective.

METHODS: The NNT for overall survival (OS) and progression-free survival (PFS) were obtained from the digitized survival curves of the pivotal trials (using Engauge Digitizer software): EMPOWER-Lung 1 (cemiplimab) and KEYNOTE-024 (pembrolizumab). Considering 18-month median follow-up of the shorter trial (EMPOWER-Lung 1), the 12 and 18-month timepoints were considered for NNT calculations. Treatment costs were estimated using labelled dosing, median duration of treatment (6.3 and 7.9 months for cemiplimab and pembrolizumab, respectively, from pivotal trials) as proxy for treatment duration and drugs ceiling prices in the private setting (obtained from CMED). COPE was calculated as the median treatment duration multiplied by the unrounded NNT and CMED list prices; for NNT results presentation, numbers were rounded to its closest integer.

RESULTS: The control groups (chemotherapy) had similar 12-month OS results: 53.6% in the KEYNOTE-024 and 54.1% in the EMPOWER-Lung 1. The rounded OS NNT were 5 for cemiplimab and 6 for pembrolizumab, for both 12-month and 18-month timepoints. The rounded PFS NNT were 3 and 4 for cemiplimab in the 12-month and 18-month timepoints, respectively; for pembrolizumab, rounded NNT was 4 in both periods. COPE values (expressed in million Brazilian Reais) for OS were as follows: R$2.020 and R$1.793 for cemiplimab, and R$2.575 and R$2.547 for pembrolizumab, in the 12 and 18-month timepoints, respectively. For PFS, COPE values were R$1.115 and R$1.527 for cemiplimab, and R$1.550 and R$1.702 for pembrolizumab, in the 12 and 18-month timepoints, respectively.

CONCLUSIONS: Cemiplimab from EMPOWER-Lung 1 showed similar and numerically better NNT and COPE values compared to pembrolizumab from KEYNOTE-024. Longer follow-up from EMPOWER-Lung 1 will help to refine the analysis.