Dr. Johnson on the Results of the CITYSCAPE Trial in PD-L1+ NSCLC

Melissa L. Johnson, MD, associate director, Lung Cancer Research, Sarah Cannon Research Institute, discusses the results of the phase 2 CITYSCAPE trial in PD-L1—positive non–small cell lung cancer (NSCLC).

In the CITYSCAPE trial, patients with chemotherapy-naïve locally advanced or metastatic NSCLC with a PD-L1 tumor proportion score (TPS) of at least 1% were randomized to the combination of tiragolumab and atezolizumab (Tecentriq; n = 67) versus placebo plus atezolizumab (n = 68). Coprimary end points were investigator-assessed objective response rate (ORR) and progression-free survival (PFS).

According to the primary analysis, tiragolumab/atezolizumab improved ORR and median PFS compared with tiragolumab/placebo. 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). Given these results, investigators continued to evaluate the safety and efficacy of the combination, says Johnson.

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 tumor 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 atezolizumab alone, concludes Johnson.