A Review of Regimens Combining Pemetrexed With an Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitor in the Treatment of Advanced Nonsquamous Non–Small-Cell Lung Cancer
Pemetrexed is a standard first-line treatment for advanced nonsquamous non–small-cell lung cancer (NSCLC), and epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) are a standard first-line treatment for advanced nonsquamous NSCLC with activating EGFR mutations. Pemetrexed and EGFR TKIs have different mechanisms of action and minimally overlapping toxicity profiles; therefore, it is hypothesized that their combination might result in acceptable toxicity, provided that the synergistic antitumor activity observed in preclinical studies is achieved. This review summarizes clinical trials of pemetrexed in combination with an EGFR TKI for the treatment of advanced nonsquamous NSCLC in the first- and second-line settings, using intercalated, sequential, and concurrent treatment strategies. As would be expected, such strategies were most efficacious in patients with the activating EGFR mutations associated with response to an EGFR TKI. In the studies that compared a pemetrexed-EGFR TKI combination with pemetrexed alone or the EGFR TKI alone, the pemetrexed-EGFR TKI combination was more efficacious than the single-agent regimens. The pemetrexed-EGFR TKI combinations were generally associated with a higher incidence of grade 3/4 treatment-related adverse events than the single-agent regimens; however, such toxicities were clinically manageable. Future studies of pemetrexed-EGFR TKI combinations should focus on optimizing treatment strategies in patients with activating EGFR mutations.