Atezolizumab is being investigated in addition to other chemotherapy (carboplatin and etoposide) as an initial (first-line) treatment for patients with extensive stage small cell lung cancer (ES-SCLC). SCLC is one of the two main types of lung cancer and the ES-SCLC means that the cancer has spread beyond a single area that can be treated with radiotherapy. The most common symptoms of lung cancer include cough, coughing up blood or rust-coloured sputum, chest pain, and shortness of breath, hoarseness, and weight loss.
Atezolizumab, given by intravenous infusion, acts by binding to a protein called anti-programmed death-ligand 1 (PD-L1) that is found on the cancer cells or immune cells trying to attack cancer cells. Binding to this protein can lead to the activation of the body’s immune system to fight tumour cells. Some studies have reported that the addition of atezolizumab to chemotherapy (carboplatin and etoposide) has the potential to increase survival and in patients with ES-SCLC who have not previously received any treatment, when compared to chemotherapy alone.
Olaparib belongs to a group of drugs called PARP enzyme inhibitors while bevacizumab is an anti-VEGF monoclonal antibody. Both drugs act in different but synergistic ways to kill tumour cells. It is thought that bevacizumab may increase the sensitivity of olaparib to killing the tumour cells. Olaparib administered orally as a monotherapy is already licensed as a maintenance therapy of advanced ovarian cancer. The addition of bevacizumab given by intravenous infusions may potentially improve treatment outcomes.