Low-dose erlotinib may be a safe and effective option for frail or elderly patients with EGFR mutation-positive non–small cell lung cancer (NSCLC), according to the results of a single-arm, multicenter phase 2 trial in JAMA Oncology (UMIN-CTR Identifier: UMIN000015949).
The trial included 80 patients with EGFR mutation–positive NSCLC from 21 Japanese institutions who received erlotinib 50 mg per day, termed low-dose erlotinib. The recommended dose for erlotinib is 150 mg per day, which is the maximum tolerated dose. Low-dose erlotinib would be deemed effective if 48 of 80 patients, or 60%, had a response.
Study participants had a median age of 80 years (range, 49-90 years). Most were men (68%), had stage IV (64%) or recurrent disease (31%), and had an Eastern Cooperative Oncology Group (ECOG) performance status of 1 (58%) or 2 (19%).
The study met the criteria for efficacy, showing an overall response rate of 60% (90% CI, 50.2%-69.2%), which included 47 partial responses and 1 complete response. A total of 24 patients had stable disease and 5 progressive disease, yielding a disease control rate of 90%.
At a median follow-up of 28.7 months, patients lived a median of 9.3 months free of disease progression (95% CI, 7.2-11.4 months) and 26.2 months overall (95% CI, 21.9-30.4 months).
No patients died from treatment and no patients had treatment-related interstitial lung disease. As a result of adverse events, 10 patients had their treatment temporarily suspended, 5 had their dose reduced to 25 mg per day, and 2 had their treatment stopped.
A pharmacokinetic analysis of plasma erlotinib concentrations showed a median trough of 685 ng/mL, which was higher than the level considered effective: 500 ng/mL.
“Low-dose erlotinib was associated with efficacy and safety in frail patients with EGFR mutation–positive lung cancer,” the study authors concluded. “More research on the dosing strategy of target-based drugs is warranted, especially in frail patients in the real-world setting.”
Miyamoto S, Azuma K, Ishii H, et al. Low-dose erlotinib treatment in elderly or frail patients with EGFR mutation-positive non-small cell lung cancer: A multicenter phase 2 trial [published online May 14, 2020]. JAMA Oncol. doi: 10.1001/jamaoncol.2020.1250