Genentech reported positive results from the IMpower133 study after the trial met its co-primary endpoints of overall survival (OS) and progression-free survival (PFS) at the first interim analysis.
IMpower133 is a Phase III, multicentre, double-blinded, randomised placebo-controlled trial designed to investigate the efficacy and safety of Tecentriq (atezolizumab) in combination with carboplatin and etoposide versus chemotherapy (carboplatin plus etoposide) alone in chemotherapy-naïve patients with extensive-stage small cell lung cancer (ES-SCLC).
The trial enrolled 403 patients randomised equally in a 1:1 ratio to receive Tecentriq in combination with carboplatin and etoposide, or a placebo in combination with carboplatin and etoposide.
Findings showed that initial treatment with the combination of Tecentriq plus chemotherapy (carboplatin and etoposide) helped ES-SCLC patients live significantly longer compared to chemotherapy alone.
The Tecentriq-based combination has also minimised the risk of disease worsening or death (PFS) compared to chemotherapy alone.
The trial further found consistency in terms of safety of Tecentriq and chemotherapy with the known safety profile of the individual medicines. No new safety signals were reported with the combination.
Genentech chief medical officer and global product development head Sandra Horning said: “These are the first positive Phase III survival results for any immunotherapy-based combination in the initial treatment of ES-SCLC, a particularly difficult-to-treat type of disease.
“The clinically meaningful results from the IMpower133 study add to the growing body of evidence demonstrating that Tecentriq-based combinations may be an effective treatment for different types of advanced lung cancer.”
Tecentriq is a monoclonal antibody designed to bind the PD-L1 protein expressed on tumour cells and tumour-infiltrating immune cells, blocking its interactions with both PD-1 and B7.1 receptors.