Results from the IMmotion150 Phase 2 clinical trial, a global, multicentre, randomised study to compare the safety and effectiveness of atezolizumab (Tecentriq) in combination with bevacizumab (Avastin) with atezolizumab alone and sunitinib (Sutent) alone, were presented at the American Society of Clinical Oncology (ASCO) Genitourinary Cancers Symposium in Orlando USA last week. The results showed that patients with locally advanced or metastatic renal cell carcinoma (RCC) who express the PD-L1 protein and who had not received any prior treatment benefit more from the combination of atezolizumab plus bevacizumab than from treatment with atezolizumab alone or from sunitinib alone.

Results showed that patients with the PD-L1 protein in their tumour cells had a 36% lower risk of their disease progressing when given atezolizumab plus bevacizumab, compared to sunitinib alone. These patients had a median progression-free survival (PFS) that was nearly double that seen in the sunitinib group (14.7 months vs. 7.8 months). However, this result was not statistically significant and the primary endpoint of the study was not reached. Since this trial was “a hypothesis-generating trial,………not designed for registration or approval”, the decision was made to continue with development of the atezolizumab plus bevacizumab combination with a phase III study powered for PFS in patients with PD-L1-positive tumours.