medwireNews: The overall survival (OS) benefit of immunotherapy in elderly patients with advanced non-small-cell lung cancer (NSCLC) is unclear according to two studies with contradictory results presented at the European Lung Cancer Congress 2019 in Geneva, Switzerland.
The first study, a pooled analysis of data from the KEYNOTE-010, KEYNOTE-024, and KEYNOTE-042 trials, found that 54% of 149 patients aged 75 years and older with a PD-L1 tumor proportion score (TPS) of at least 1% were still alive after 12 months of treatment with the PD-1 inhibitor pembrolizumab.
By comparison, 48% of 115 patients treated with chemotherapy were alive at the same timepoint, giving a borderline significant hazard ratio (HR) of 0.76 in favor of pembrolizumab.
The same HR was achieved, although this time statistically significant, for patients younger than 75 years with 12-month OS rates of 55% and 46% for pembrolizumab and chemotherapy, respectively.
However, when the analysis was restricted to individuals with a PD-L1 TPS of 50% or higher, the older patients appeared to derive greater benefit from pembrolizumab relative to chemotherapy than younger patients.
Specifically, 12-month OS was 62% in both age groups treated with pembrolizumab, but was just 30% among the older patients who received chemotherapy and 49% among the younger patients, resulting in significant HRs of 0.40 and 0.67 for the older and younger patients, respectively.
The safety profile of pembrolizumab was similar between the two age groups, with 23% of older patients and 16% of younger patients experiencing grade 3–4 adverse events, 1% of which led to death in each group. The rate of immune-mediated adverse events or infusion reactions was also the same, at 25%, irrespective of age.
Presenting author Kaname Nosaki, from the National Hospital Organization Kyushu Cancer Center in Fukuoka, Japan, concluded: “These data support the use of pembrolizumab monotherapy in elderly patients (≥75 years) with advanced PD-L1‒expressing NSCLC.”
But Elena Corral de la Fuente and colleagues, from the Hospital Universitario Ramon y Cajal in Madrid, Spain, said in a press release that the results of their observational study, which they presented in a poster, “suggest that elderly patients could have worse survival outcomes with immunotherapy than younger patients.”
Their analysis of 98 patients (mean age 62 years) who were treated with anti-PD-1 or anti-PD-L1 monotherapy for advanced NSCLC showed that the median OS duration was significantly shorter among patients aged 70 years and older (n=27) than among younger patients, at 5.5 versus 13.0 months (HR=3.86).
Progression-free survival was also significantly shorter in the older patients, at 1.8 months, compared with 3.6 months in the younger patients (HR=2.10).
Nonetheless, in line with the findings of Nosaki and team, Corral de la Fuente and co-investigators found that increased age was not associated with a higher rate of immune-mediated adverse events.
And the authors of the poster conclude: “Prospective randomised clinical trials and more real-world data are needed to answer remaining questions on the use of immunotherapy in elderly patients.”
By Laura Cowen
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ELCC 2019; Geneva, Switzerland: 10–13 April