A phase 3 study evaluating tiragolumab in combination with atezolizumab (Tecentriq®) and chemotherapy (carboplatin and etoposide) as first-line treatment for patients with extensive-stage small cell lung cancer (ES-SCLC) did not meet its coprimary endpoint.

Tiragolumab is a monoclonal antibody that works by binding to TIGIT, a protein receptor on immune cells, and suppresses the immune response to cancer. The Company believes that combining tiragolumab with atezolizumab, a PD-L1 blocking antibody, will increase anti-tumor activity by enhancing the body’s immune response to cancer cells. 

The global, randomized, placebo-controlled, double-blind, SKYSCRAPER-02 study (ClinicalTrials.gov Identifier: NCT04256421) evaluated the efficacy and safety of tiragolumab plus atezolizumab and carboplatin and etoposide (CE) in 490 chemotherapy-naive adults with ES-SCLC. Patients were randomly assigned to receive tiragolumab plus atezolizumab and CE or placebo plus atezolizumab and CE.

Findings demonstrated that treatment with tiragolumab plus atezolizumab and CE did not the coprimary endpoint of progression-free survival. Moreover, the coprimary endpoint of overall survival was not met at its interim analysis and is unlikely to reach statistical significance at the planned final analysis. The safety profile of tiragolumab plus atezolizumab and CE was well tolerated with no new safety signals identified. 

Study data will be presented at an upcoming meeting.

“Today’s outcome is disappointing as we had hoped to continue building on the advances of Tecentriq in extensive stage small-cell lung cancer, which remains difficult to treat. We are thankful to all the patients and healthcare professionals involved in the study,” said Levi Garraway, MD, PhD, chief medical officer and head of Global Product Development. “We look forward to seeing additional data from the upcoming Phase III trial in PD-L1-high non-small cell lung cancer based on the encouraging results from the CITYSCAPE study.”

The FDA previously granted Breakthrough Therapy designation to tiragolumab in combination with atezolizumab for the first-line treatment of patients with metastatic non-small cell lung cancer (NSCLC) whose tumors have high PD-L1 expression with no EGFR or ALK genomic tumor aberrations. The designation was supported by data from the phase 2 CITYSCAPE study (ClinicalTrials.gov Identifier: NCT03563716).

The Company is also investigating the combination of tiragolumab and atezolizumab for the treatment of metastatic NSCLC (SKYSCRAPER-01 [ClinicalTrials.gov Identifier: NCT04294810]), stage III NSCLC (SKYSCRAPER-03 [ClinicalTrials.gov Identifier: NCT04513925]), and locally advanced esophageal cancer (SKYSCRAPER-07 [ClinicalTrials.gov Identifier: NCT04543617]). Tiragolumab is also being evaluated for the treatment of metastatic esophageal squamous cancer (SKYSCRAPER-08 [ClinicalTrials.gov Identifier: NCT04540211]).


Genentech provides update on phase III SKYSCRAPER-02 study in extensive-stage small cell lung cancer. News release. Genentech. Accessed March 30, 2022. https://www.businesswire.com/news/home/20220329005953/en/Genentech-Provides-Update-on-Phase-III-SKYSCRAPER-02-Study-in-Extensive-Stage-Small-Cell-Lung-Cancer