In patients with metastatic non-small cell lung cancer (NSCLC), the administration of erlotinib at doses below the maximum tolerated dose (MTD) resulted in a high response rate and a prolonged median progression-free survival, according to a study published in Cancer.1
Erlotinib is a standard frontline treatment option for patients with metastatic EGFR mutation-positive NSCLC. The recommended dose of erlotinib is 150 mg daily, which is also the MTD.
Because limited data on the efficacy of erlotinib at doses less than the MTD exist, researchers sought to retrospectively evaluate the efficacy of erlotinib given at doses of 100 mg or less.
For the study, investigators analyzed data from 198 patients with advanced NSCLC who harbored EGFR L858R mutations or exon 19 deletions and had received first-line erlotinib therapy.
Results showed that 16% of patients were initiated on erlotinib at a reduced dose. Those patients were more likely to be older (P = .001) and have a lower performance status (P = .01) compared with patients who received erlotinib at the MTD.
Among patients who received reduced-dose erlotinib, the response rate was 77% and the median progression-free survival was 9.6 months compared with 11.4 months with the MTD of erlotinib (hazard ratio [HR], 0.81; 95% CI, 0.54-1.21; P = .30).
However, the study revealed a nonsignificant trend toward higher rates of progression within the central nervous system in patients who received reduced-dose erlotinib.
Lampson BL, Nishino M, Dahlberg SE, et al. Activity of erlotinib when dosed below the maximum tolerated dose for EGFR-mutant lung cancer: Implications for targeted therapy development. Cancer. 2016 Aug 15. doi: 10.1002/cncr.30270. [Epub ahead of print]