Tiragolumab Plus Atezolizumab Improves PFS vs Placebo Plus Atezolizumab in NSCLC: CITYSCAPE Trial

Tiragolumab plus atezolizumab yielded improved objective response rates and progression-free survival (PFS) vs placebo plus atezolizumab among patients with previously untreated, unresectable, or metastatic NSCLC, according to results from the phase 2 CITYSCAPE trial.

 “Not all patients respond to immunotherapy, and a great unmet need for new therapies and combinations persists,” explained Byoung Chul Cho, MD, PhD, Yonsei Cancer Center, Yonsei University College of Medicine, Seoul, South Korea, and colleagues, adding, “The aim of the CITYSCAPE study was to test the hypothesis that the addition of tiragolumab to atezolizumab provides more clinical benefit than atezolizumab monotherapy.”

This trial assessed 275 patients, 135 of whom were randomized in a 1:1 ratio to receive tiragolumab plus atezolizumab (n = 67) or placebo plus atezolizumab (n = 68) intravenously once every 3 weeks. The co-primary end points of the trial were objective response rate and PFS. Secondary end points included duration of response, and overall survival (OS).

After a median follow-up of 5.9 months, the objective response rate in the tiragolumab group was 31.3% (n = 21) and 16.2% (n = 11) in the placebo group (P = .031). The median PFS was 5.4 months (95% confidence interval [CI], 4.2 to not estimable) and 3.6 months (stratified hazard ratio [HR], 0.57; 95% CI, 0.37 to 0.90; P = .015), respectively.

“These findings demonstrate that tiragolumab plus atezolizumab is a promising immunotherapy combination for the treatment of previously untreated, locally advanced unresectable or metastatic NSCLC,” wrote Dr Cho and colleagues.

Serious treatment-related adverse events were reported in 14 (21%) patients in the tiragolumab plus atezolizumab group and 12 (18%) in the placebo plus atezolizumab group. The most common treatment-related adverse event was lipase increase (6 [9%] with tiragolumab plus atezolizumab and 2 [3%] with placebo plus atezolizumab).

“Atezolizumab showed a significant and clinically meaningful survival benefit over chemotherapy in previously untreated patients with advanced NSCLC,” concluded Dr Cho et al.

Source:                                        

Cho BC, Abreu DR, Hussein M, et al. Tiragolumab plus atezolizumab versus placebo plus atezolizumab as a first-line treatment for PD-L1-selected non-small-cell lung cancer (CITYSCAPE): primary and follow-up analyses of a randomised, double-blind, phase 2 study. Lancet Oncol. 2022;23(6):781-792. doi:10.1016/S1470-2045(22)00226-1.