Tiragolumab and atezolizumab: ORR in NSCLC

Tiragolumab and atezolizumab showed improved objective response rate over placebo and atezolizumab in chemotherapy-naïve locally advanced or metastatic non-small cell lung cancer (NSCLC).

Dr Delvys Rodriguez-Abreu (NYU Perlmutter Cancer Center, USA) presented the phase 2 CITYSCAPE trial, which tested chemotherapy-naïve patients with PD-L1-positive, locally advanced or metastatic NSCLC [1]. Participants were randomised to the combination of tiragolumab and atezolizumab (n=67) or placebo plus atezolizumab (n=68). Co-primary endpoints were investigator-assessed objective response rate (ORR) and progression-free survival (PFS).

The primary analysis indicated that tiragolumab/atezolizumab improved ORR and median PFS compared with placebo/atezolizumab. The ORR was 31.3% in the tiragolumab arm versus 16.2% in the placebo arm. The median PFS was 5.4 months and 3.6 months in the tiragolumab and placebo arms, respectively (HR 0.57).

According to the updated analysis, the ORR was 37.3% versus 20.6% in the tiragolumab and placebo arms, respectively. Investigators also stratified patients according to PD-L1 tumour proportion score (TPS between 1% and 49% versus at least 50%). Patients with a PD-L1 TPS of at least 50% derived even more benefit from tiragolumab/atezolizumab, with an ORR of 66% versus 24% with placebo/atezolizumab.

1. Rodriguez-Abreu D, et al. ASCO Virtual Meeting, 29-31 May 2020, Abstract 9503.

Posted on 8 September 202022 February 2024