Immune checkpoint inhibitors rely on the presence of ongoing immune response to exert their antitumor effect.
Little is known whether an age-related decline in immune function negatively influences antitumor response and in so doing diminishes the efficacy of immune checkpoint inhibitors in elderly subjects.
Researchers have performed a meta-analysis to compare the efficacy of immune checkpoint inhibitors between younger and older patients.
PubMed and the ASCO databases were searched up to September 2015.
Randomized controlled trials ( RCTs ) of immune checkpoint inhibitors ( Ipilimumab, Tremelimumab, Nivolumab and Pembrolizumab ) reporting subgroup comparison of overall survival ( OS ) and/or progression-free survival ( PFS ) based on age cutoffs were included.
A total of 5265 patients from nine RCTs of immune checkpoint inhibitors were included.
When patients were dichotomized into younger and older groups with an age cut-off of 65-70 years, immune checkpoint inhibitors improved overall survival in both younger ( hazard ratio, HR, 0.75; 95% CI, 0.68-0.82 ) and older ( HR, 0.73; 95% CI, 0.62-0.87 ) groups.
An improvement in progression-free survival was observed in younger ( HR, 0.58; 95% CI, 0.40-0.84 ) and older ( HR, 0.77; 95% CI, 0.58-1.01 ) patients.
Subgroup analyses according to immune checkpoint inhibitors and tumor type showed a consistent survival benefit in both younger and older groups except for the subgroup of older patients treated in 4 trials of anti-programmed cell death protein-1 ( PD-1 ) monoclonal antibody ( HR, 0.86; 95% CI, 0.41-1.83 ).
In conclusion, a benefit in overall survival with immune checkpoint inhibitors was significant in both younger and older patients with a cut-off age of 65-70 years. ( Xagena )
Nishijima TF et al, Cancer Treat Rev 2016; 45:30-37