Pembrolizumab as first-line treatment for advanced NSCLC in older adults: A phase II clinical trial evaluating geriatric and quality-of-life outcomes

Abstract

Objectives: Since specific data on immunotherapy in older adults with advanced non-small cell lung cancer (aNSCLC) are scarce, we designed this study to determine the overall survival (OS) at one year of first-line pembrolizumab in patients older than 70 years with aNSCLC expressing PD-L1. Secondary objectives included progression-free survival, disease-specific survival, response rate, tolerability, quality of life (QoL) changes, and geriatric assessments.

Materials and methods: A single-arm, open-label, phase II clinical trial was carried out by the Spanish Lung Cancer Group between February 2018 and November 2019 at ten active sites in Spain. We included patients 70 years old and older with histological or cytological documented stage IIIB or IV aNSCLC and PD-L1 expression ≥ 1%. Each subject received 200 mg of intravenous pembrolizumab every three weeks for a maximum of two years.

Results: 83 patients were recruited for the study and 74 were finally analysed. Most were male (N = 64, 86.5%) and former smokers (N = 51, 68.9%). 24 patients (32.4%) completed at least one year of treatment, 62 (83.7%) discontinued treatment, and 30 (40.5%) experienced disease progression. The median follow-up of our cohort was 18.0 months [range: 0.1-47.7] and 46 patients (62.2%) died during the period of study. The estimated OS at one year was 61.7% (95% CI: 49.6-71.8%) and the median OS of our cohort was 19.2 months (95% CI: 11.3-25.5). QoL tended to improve throughout the study, although the differences were not statistically significant. The main geriatric scores remained stable, except for a worsening in nutritional status (P = 0.004) and an improvement in frailty (P = 0.028).

Conclusion: Our results support treating older adults with aNSCLC expressing PD-L1 with pembrolizumab in monotherapy. The stability of most geriatric scores and the positive trend on the patients' QoL should be highlighted, although our results did not reach statistical significance.

Keywords: Geriatric outcomes; Non-small cell lung cancer; Older adults; Overall survival; Pembrolizumab; Quality of life.