The CAPER Trial will investigate if adding an additional drug (cyclophosphamide) to an immunotherapy drug (pembrolizumab) increases the response of cancer to the immunotherapy. We will be looking at patients with metastatic clear cell renal cell carcinoma (a type of kidney cancer that has spread to other parts of the body) for which there are no standard existing chemotherapies available and who have had previous treatment with immunotherapy which has not been effective.
Immunotherapy is a type of cancer treatment that boosts the body’s natural defences to fight cancer. Every cancer has a slightly different environment in which the tumour exists this includes the surrounding blood vessels, immune cells and signalling molecules. This environment affects the way our body responds to cancer treatment and how well it works at reducing the cancer growth and spread. The trials aims to see if adding cyclophosphamide can alter the tumour environment and lead to better response to the pembrolizumab.
Patients who join the study will take cyclophosphamide 50mg tablets once a day for 21 days before adding intravenous (given directly into your blood through a drip) pembrolizumab treatment one day every three weeks. Patients will be on both treatments until there are signs that cancer is growing and treatment is no longer working. Treatment will also be stopped if patients have too many side effects; a maximum 24 months of treatment; or the tumour has shown a good response.
Patients will be scanned every 9 weeks and will also have additional blood and biopsies taken to assess response.