A Phase I Study of Erlotinib and Hydroxychloroquine in Advanced Non-Small-Cell Lung Cancer

Introduction: This investigator-initiated study explores the safety, maximum tolerated dose, clinical response, and pharmacokinetics of hydroxychloroquine (HCQ) with and without erlotinib in patients with advanced non-small-cell lung cancer. Methods: Patients with prior clinical benefit from an epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor were randomized to HCQ or HCQ plus erlotinib in a 3 + 3 dose-escalation schema. Results: Twenty-seven patients were treated, eight with HCQ (arm A) and 19 with HCQ plus erlotinib (arm B). EGFR mutations were detected in 74% of the patients and 85% had received two or more prior therapies. Arm A had no dose-limiting toxicities, but the maximum tolerated dose was not reached as this arm closed early to increase overall study accrual. In arm B, one patient each experienced grade 3 rash, nail changes, skin changes, nausea, dehydration, and neutropenia; one had grade 4 anemia; and one developed fatal pneumonitis, all considered unrelated to HCQ. There were no dose-limiting toxicities, therefore the highest tested dose for HCQ with erlotinib 150 mg was 1000 mg daily. One patient had a partial response to erlotinib/HCQ, for an overall response rate of 5% (95% confidence interval, 1-25). This patient had an EGFR mutation and remained on therapy for 20 months. Administration of HCQ did not alter the pharmacokinetics of erlotinib. Conclusions: HCQ with or without erlotinib was safe and well tolerated. The recommended phase 2 dose of HCQ was 1000 mg when given in combination with erlotinib 150 mg.