When excluding those with the highest expression, a benefit was still observed with the atezolizumab combination. In those with TC/IC 0/1/2, the median PFS was 8.0 months with atezolizumab compared with 6.8 months in the control arm (HR, 0.68). Even in the negative group specifically (TC/IC0), there was a 23% reduction in the risk of death with atezolizumab (HR, 0.77; 95% CI, 0.61-0.99). "For these patients, I'd like to see the shape of the curves over time," she said.
In a preliminary examination of OS, there was a 22.5% reduction in the risk of death with the atezolizumab combination compared with bevacizumab and chemotherapy alone. After a minimum follow-up of 9.5 months, the median OS was 14.4 months (95% CI, 12.8-17.1) versus 19.2 months (95% CI, 16.8-26.1), in favor of the atezolizumab group (HR, 0.775; 95% CI, 0.619-0.970; P
= .0262). The next OS analysis will take place in the first half of 2018.
"Only 45% of events for the survival curve had occurred, so it is still too early to look at that," said Peters. "We need more time but I hope that the curve will separate more over time, which will make it significant."
Atezolizumab continues to be assessed in other frontline combination strategies. A phase Ib study is looking at the PD-L1 inhibitor in combination with erlotinib (Tarceva) for EGFR-mutant NSCLC or alectinib (Alecensa) for ALK-mutant NSCLC (NCT02013219). Additionally, several studies in the IMpower development program are looking at atezolizumab with standard chemotherapy regimens (IMpower 130, 131, and 132).
- 1. Reck M. Primary PFS and safety analyses of a randomized Phase III study of carboplatin + paclitaxel +/− bevacizumab, with or without atezolizumab in 1L non-squamous metastatic NSCLC (IMpower150). Annals of Oncology. 2017;28(11). Abstract LBA1_PR.
- 1. Brahmer JR, Rodríguez-Abreu D, Robinson AG, et al. Updated analysis of KEYNOTE-024: pembrolizumab vs platinum-based chemotherapy for advanced NSCLC with PD-L1 TPS ≥50%. Presented at: the IASLC 18th World Conference on Lung Cancer; October 15-18; Yokohama, Japan. Abstract OA 17.06 (ID 9582).