EGFR TKI combination with immunotherapy in non-small cell lung cancer.

INTRODUCTION: Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKI) has significantly improved clinical outcomes compared with chemotherapy in non-small cell lung cancer (NSCLC) patients with sensitizing EGFR gene mutation. Areas covered: Almost all patients treated with EGFR TKIs eventually develop acquired resistance. It has been reported that activation of the oncogenic EGFR pathway enhances susceptibility of the lung tumors to PD-1 blockade in mouse model, suggesting combination of PD1 blockade with EGFR TKIs may be a promising therapeutic strategy. Nivolumab combined with erlotinib was associated with 19% of grade 3 toxicities. The combination of osimertinib plus durvalumab in pretreated or chemo naïve NSCLC patients showed encouraging clinical activity, however, this combination was associated with high incidence of interstitial lung disease (38%), leading to termination of further enrollment. The combination of gefitinib plus durvalumab demonstrated encouraging activity but higher incidence of grade 3/4 liver enzyme elevation (40-70%). The treatment related Grade 3-4 adverse events were observed in 39% of patients when treated with atezolizumab plus erlotinib. Expert opinion: Given the relatively high incidence of treatment-related toxicities associated with combination of EGFR TKI and immunotherapy, further development of this approach remains controversial. Until now, the combination of EGFR TKI and immunotherapy should be investigational.