Roche company Genentech has announced that its investigational cancer immunotherapy atezolizumab (MPDL3280A, anti-PDL) has reached the primary endpoint in the Birch pivotal Phase II study.
Atezolizumab is an investigational monoclonal antibody designed to target programmed death ligand-1 (PD-L1) expressed on tumour cells (TC) and tumour-infiltrating immune cells (IC), preventing it from binding to PD-1 and B7.1 on the surface of T cells.
According to the firm, atezolizumab shrank tumours in people with locally advanced or metastatic non-small cell lung cancer (NSCLC) whose disease expressed PD-L1.
The trial demonstrated the amount of PD-L1 expressed by a person’s cancer correlated with their response to the medicine.
Genentech senior vice-president and chief medical officer Dr Sandra Horning said: "We are encouraged by the number of people who responded to atezolizumab and maintained their response during the study, which is particularly meaningful for people who had received several prior treatments.
"We plan to present results at an upcoming medical meeting and will discuss these data as well as results from our other lung cancer studies with health authorities to bring this medicine to patients as quickly as possible."
Birch study is an open-label, multicentre and single-arm Phase II trial, which assessed the safety and efficacy of atezolizumab in 667 people with locally advanced or metastatic NSCLC whose disease expressed PD-L1.
PD-L1 expression has been evaluated on both TC and tumour-infiltrating IC with an investigational immunohistochemistry test (IHC) being developed by Roche Diagnostics.
The primary endpoint of the study was objective response rate (ORR), while secondary endpoints comprised duration of response (DoR), overall survival (OS), progression-free survival (PFS) and safety.
Earlier this year, atezolizumab received breakthrough therapy designation from the FDA to treat people whose NSCLC expresses PD-L1 and who progressed during or after standard treatments.