The following is a summary of “SKYSCRAPER-02: Tiragolumab in Combination With Atezolizumab Plus Chemotherapy in Untreated Extensive-Stage Small-Cell Lung Cancer,” published in the November 2023 issue of Oncology by Rudin, et al.
The phase III SKYSCRAPER-02 study aimed to assess the potential enhancement of the benefits derived from atezolizumab plus carboplatin and etoposide (CE) by incorporating tiragolumab in the treatment of previously untreated extensive-stage small-cell lung cancer (ES-SCLC).
For a study, researchers sought to present the final analyses of progression-free survival (PFS) and overall survival (OS).
Patients received tiragolumab 600 mg/placebo in addition to atezolizumab 1,200 mg and CE (four cycles), followed by maintenance tiragolumab/placebo plus atezolizumab. The primary endpoints were investigator-assessed PFS and OS in patients without a history or presence of brain metastases (primary analysis set [PAS]). Additional endpoints encompassed PFS and OS in all patients, regardless of brain metastasis status (full analysis set [FAS]), response rates, and safety.
About 490 patients were randomly assigned (FAS): 243 to the tiragolumab arm and 247 to the control arm. At the cutoff date (February 6, 2022; median follow-up duration, 14.3 months [PAS] and 13.9 months [FAS]), the final PFS analysis in the PAS (n = 397) did not reach statistical significance (stratified HR, 1.11; P = .3504; median, 5.4 months tiragolumab vs. 5.6 months control). At the cutoff date (September 6, 2022; median follow-up duration, 21.2 months [FAS]), the final OS analysis revealed a median OS of 13.1 months in both arms (stratified HR, 1.14; P = .2859). Median PFS and OS in the FAS were consistent with the PAS. The incidence of immune-mediated adverse events (AEs) in the tiragolumab and control arms was 54.4% and 49.2%, respectively (grade 3/4: 7.9% and 7.7%). AEs leading to treatment withdrawal occurred in 8.4% and 9.3% of tiragolumab- and control-treated patients, respectively.
The addition of tiragolumab did not confer additional benefits over atezolizumab and CE in the treatment of previously untreated ES-SCLC. The combination demonstrated good tolerability, with no emergence of new safety signals.