Afatinib + bevacizumab combination therapy in EGFR‐mutant NSCLC patients with osimertinib resistance: Protocol of an open‐label, phase II, multicenter, single‐arm trial

INTRODUCTION: As most patients with epidermal growth factor receptor (EGFR)‐mutant non‐small cell lung cancer (NSCLC) develop progressive disease after treatment with osimertinib, it is important to develop more effective treatment options. Afatinib has been shown to be more effective in in vitro studies than osimertinib when used in cancer cell lines containing some specific EGFR mutations. Therefore, afatinib may be an effective solution, especially when used in combination with an anti‐VEGF agent such as bevacizumab. METHODS: A phase II multicenter, open‐label, single‐arm trial has been initiated to evaluate the efficacy and safety of afatinib and bevacizumab combination as salvage therapy for EGFR‐mutated lung cancer in patients previously treated with osimertinib. The primary endpoint will be the objective response rate (ORR) and secondary endpoints are progression‐free survival (PFS), overall survival (OS), disease control rate (DCR), and adverse events (AEs). DISCUSSION: A previous study indicated that afatinib inhibits lung cancer cells with specific EGFR mutations more effectively than other EGFR‐TKIs such as osimertinib. Therefore, we expect that combination therapy using afatinib and bevacizumab will be effective in patients previously treated with osimertinib (registration no. jRCTs031190077).