29P Real-world data of atezolizumab in combination with bevacizumab, and platinum-based chemotherapy for EGFR-mutant metastatic non-small cell lung cancer patients after failure of EGFR tyrosine kinase inhibitors

IMpower150 study showed that the combination of immune chemotherapy plus bevacizumab provided a favorable efficacy for patients with non-squamous lung cancer harboring EGFR mutations. Although its effectiveness has been approved, little is known about the clinical outcome of the combination therapy in routine practice, especially for the Asian population with high EGFR mutation incidence. The current study aimed to explore the clinical efficacy and prognosis of combinational treatment with atezolizumab, bevacizumab, and platinum-based chemotherapy in patients with EGFR-mutated lung cancer who progressed with standard EGFR-targeted therapies. From April 2019 to June 2022, we retrospectively collected patient-level data on atezolizumab-bevacizumab-chemotherapy combination treatment in NSCLC patients with EGFR mutations after the failure of EGFR TKIs at the National Taiwan University Hospital. The patient’s clinical characteristics and treatment outcomes were recorded. We collected 36 patients, including 28 females and 35 non-smokers. The median age was 59.5 (range 40.4–81.3) years. EGFR mutation types included 13 deletion in exon19, 19 L858R, and 4 uncommon types. Before the combination therapy, 24 (66.7%) patients and 11 (30.6%) patients have taken osimertinib and anti-angiogenesis, respectively. PD-L1 expression was $$ 1% in 19 (52.8%) patients. The treatment outcomes included a response rate of 44.4% (16 of 36), median progression-free survival (mPFS) of 7.8 months, and median overall survival of 16.7 months. Patients with PD-L1 expression 2: 1% have a loner mPFS than those with PD-L1 expression $$ 1% or unknown (10.6 months vs. 2.5 months vs. 7.8 months; p < 0.001). There were no significant differences in response rates and PFS between patients with and without malignant pleural effusion, liver, or brain metastasis. The combination treatment of atezolizumab, bevacizumab, pemetrexed, and cisplatin/carboplatin provided favorable efficacy in EGFR mutation-positive NSCLC after TKI failure, and higher PD-L1 expression ($$ 1%) was associated with longer PFS.