Optimising regulatory T cell depletion with cyclophosphamide in combination with chemotherapy for enhanced anti-tumour immunity in patients with non-small cell lung cancer (NSCLC) and malignant mesothelioma (MM).

This study is testing whether adding a low dose of the drug cyclophosphamide to standard chemotherapy can help the immune system fight cancer better. It is for people with advanced lung cancer (non-small cell type) or a cancer of the lining around the lungs called malignant mesothelioma. The idea is that cyclophosphamide may remove certain immune cells that are blocking the body's natural defences against the cancer. You may be eligible if: - You are 18 years or older - You have been diagnosed with advanced non-small cell lung cancer or malignant mesothelioma - Your cancer is being treated with a chemotherapy regimen that includes pemetrexed - You are in generally good physical condition (ECOG performance status 0 or 1) - You are receiving treatment with the aim of managing (not curing) the disease You may NOT be eligible if: - You have a history of severe autoimmune disease - You are pregnant or breastfeeding - You have had radiation to all areas of measurable cancer - You have a separate cancer diagnosis (with some exceptions for past, successfully treated cancers) - You need to take oral steroids regularly during treatment - You are currently in another clinical trial or receiving immunotherapy Talk to your doctor about whether this trial might be right for you.