First- and Second-Generation EGFR-TKIs Are All Replaced to Osimertinib in Chemo-Naive EGFR Mutation-Positive Non-Small Cell Lung Cancer?

Masayuki Takeda,Kazuhiko Nakagawa

doi:10.3390/ijms20010146

Abstract

Activating mutations of the epidermal growth factor receptor gene (EGFR) are a driving force for some lung adenocarcinomas. Several randomized phase III studies have revealed that treatment with first- or second-generation EGFR tyrosine kinase inhibitors (TKIs) results in an improved progression-free survival (PFS) compared to standard chemotherapy in chemonaive patients with advanced non–small cell lung cancer (NSCLC), selected based on the presence of EGFR mutations. Patients treated with second-generation EGFR-TKIs have also shown an improved PFS relative to those treated with first-generation EGRF-TKIs. Osimertinib is a third-generation EGFR-TKI that still irreversibly inhibits the activity of EGFR after it has acquired the secondary T790M mutation that confers resistance to first- and second-generation drugs. Its efficacy has been validated for patients whose tumors have developed T790M-mediated resistance, as well as for first-line treatment of those patients with EGFR mutation–positive NSCLC. Although there are five EGFR-TKIs (gefitinib, erlotinib, afatinib, dacomitinib, and osimertinib) currently available for the treatment of EGFR-mutated lung cancer, the optimal sequence for administration of these drugs remains to be determined. In this review, we addressed this issue with regard to maximizing the duration of the EGFR-TKI treatment.

Highlights

Rapid developments in molecular biology provide the evidence that driver mutation, such as epidermal growth factor receptor (EGFR) [1,2] and anaplastic lymphoma kinase (ALK) genes [3], play an important role in the oncogenesis of non–small cell lung cancer (NSCLC)
Randomized phase III studies revealed that first-line treatment with EGFR tyrosine kinase inhibitors (TKIs) conferred an improved progression-free survival (PFS) compared with standard chemotherapy in patients with advanced NSCLC, who were selected on the basis of the presence of activating EGFR mutations [4,5,6,7,8,9] (Table 1)
EGFR-TKI monotherapy has become the standard of care for patients with advanced NSCLC that are positive for such mutations

Summary

Introduction

Rapid developments in molecular biology provide the evidence that driver mutation, such as epidermal growth factor receptor (EGFR) [1,2] and anaplastic lymphoma kinase (ALK) genes [3], play an important role in the oncogenesis of non–small cell lung cancer (NSCLC). Randomized phase III studies revealed that first-line treatment with EGFR tyrosine kinase inhibitors (TKIs) conferred an improved progression-free survival (PFS) compared with standard chemotherapy in patients with advanced NSCLC, who were selected on the basis of the presence of activating EGFR mutations [4,5,6,7,8,9] (Table 1). EGFR-TKI monotherapy has become the standard of care for patients with advanced NSCLC that are positive for such mutations. Most NSCLC patients who harbor TKI-sensitizing EGFR mutations show an initial pronounced response to EGFR-TKI treatment, they acquire a resistance to these drugs after ~9 to 14 months of such therapy. Gefitinib Erlotinib Afatinib Dacomitinib Erlotinib + Bevacizumab Osimertinib (second line) Osimertinib (first line)

Comparison between the First-Generation EGFR-TKIs

Comparison between the First- and Second-Generation EGFR-TKIs

Comparison of the First- and Third-Generation EGFR-TKIs

Findings

What Is the Best EGFR-TKI Sequence for Treatment?