Atezolizumab plus bevacizumab and chemotherapy in metastatic nonsquamous NSCLC: the randomized double-blind phase 3 IMpower151 trial
Caicun Zhou, Xiaorong Dong, Gongyan Chen, Zhehai Wang, Xianghua Wu, Yao Yu, Yiping Zhang, Ying Cheng, Hongming Pan, Xiaodong Zhang, Jiuwei Cui, Lifeng Wang, Xi Chen, Xiaoling Li, Ziping Wang, Qiming Wang, Jianxing He, Mengzhao Wang, Iris Yan, Qian Li, Miao Xu, Xiayu Huang, Chun Sun, Jun Cai, Qiong Wu, Marcus Ballinger, Monika Kaul, Minu K. Srivastava
Abstract
After the global approval of atezolizumab plus bevacizumab and chemotherapy as first-line metastatic nonsquamous non-small-cell lung cancer (nsqNSCLC) treatment, the IMpower151 ( NCT04194203 ) trial was conducted in China to address regional differences. Chemotherapy-naive patients with metastatic nsqNSCLC (N = 305) were randomized 1:1 to receive either atezolizumab, bevacizumab, carboplatin and paclitaxel or pemetrexed (ABCPem/Pac; n = 152) or placebo plus bevacizumab, carboplatin and pemetrexed or paclitaxel (BCPem/Pac; n = 153). The primary endpoint was investigator-assessed progression-free survival (INV-PFS); secondary endpoints included subgroup analyses of INV-PFS, independent review facility-assessed PFS, overall survival, and investigator-assessed objective response rate and duration of response per RECIST v.1.1. Most patients (97%) received pemetrexed, and 53% had EGFR+ tumors. Median INV-PFS for ABCPem/Pac versus BCPem/Pac was 9.5 versus 7.1 months (stratified hazard ratio: 0.84; 95% confidence interval: 0.65, 1.09; P = 0.184). INV-PFS across subgroups and independent review facility-assessed PFS were consistent with INV-PFS in the intention-to-treat population. Median overall survival was 20.7 versus 18.7 months in the ABCPem/Pac versus BCPem/Pac arms, respectively (stratified hazard ratio: 0.93; 95% confidence interval: 0.67, 1.28). Confirmed objective response rate with ABCPem/Pac versus BCPem/Pac was 48% versus 50%, respectively; median duration of response was 11.3 versus 8.3 months. Adverse events of special interest for atezolizumab were observed in 68% (grades 3 and 4: 11%) and 71% (grades 3 and 4: 7%) of patients receiving ABCPem/Pac and BCPem/Pac, respectively. The most common adverse events of special interest for atezolizumab in the ABCPem/Pac and BCPem/Pac arms were hepatitis (driven by laboratory abnormalities; mostly low grade), hypothyroidism and rash. Overall, IMpower151 did not meet its primary endpoint (INV-PFS) in metastatic nsqNSCLC. ABCPem/Pac was generally well tolerated, with no new safety signals. Trial registration number: ClinicalTrials.gov, NCT02366143 In the IMpower151 trial, the drug combination previously shown to be effective in the IMpower150 trial was not significantly effective in a Chinese population.