Roche announced that in the IMvigor 210 study, the investigational cancer immunotherapy atezolizumab (anti-PDL1) shrank tumours (objective response rate, ORR, the primary end point of this Phase II study) in people with locally advanced or metastatic urothelial bladder cancer (UBC) who had progressed on initial treatment (second-line or later). High amounts of PD-L1 (Programmed Death Ligand-1) expression by a person’s cancer correlated with increased response to the medicine. Adverse events were consistent with what has been previously observed for atezolizumab.
IMvigor 210 is an open-label, multicenter, single-arm Phase II study that evaluated the safety and efficacy of atezolizumab in people with locally advanced or metastatic UBC, regardless of PD-L1 expression. People in the study were enrolled into one of two cohorts. Cohort 1 consisted of people who had received no prior therapies for locally advanced or metastatic UBC, but who were ineligible for first-line cisplatin-based therapy; results from this cohort are not yet mature. Cohort 2, for which results were announced today, included people whose disease progressed during or following previous treatment with a platinum-based chemotherapy regimen (second-line or later). People received a 1200-milligram intravenous dose of atezolizumab on day one of 21-day cycles until progressive disease (Cohort 1) or loss of clinical benefit (Cohort 2). The primary endpoint of the study was ORR. Secondary endpoints included duration of response (DoR), overall survival (OS), progression-free survival (PFS) and safety. PD-L1 expression was assessed using an investigational immunohistochemistry (IHC) test being developed by Roche Diagnostics.
Metastatic urothelial bladder cancer is associated with a poor prognosis and limited treatment options. It is a disease that has seen no major advancements for nearly 30 years. Bladder cancer is the ninth most common cancer worldwide, with 430,000 new cases diagnosed in 2012, and it results in approximately 145,000 deaths globally each year. Men are three times more likely to suffer from bladder cancer compared with women and it is also three times more common in developed countries than in less developed countries.
Atezolizumab (also known as MPDL3280A; anti-PDL1) is an investigational monoclonal antibody designed to interfere with a protein called PD-L1. Atezolizumab is designed to target PD-L1 expressed on tumour cells and tumour-infiltrating immune cells, preventing it from binding to PD-1 and B7.1 on the surface of T cells. By inhibiting PD-L1, atezolizumab may enable the activation of T cells.