If there is a great new hope in the treatment of cancer, the immune system is it. Over the past dozen years, 71 anticancer drugs have been approved by US regulators. Typically they extend the lives of patients by only two months. And they are not cheap. A month of anti-cancer therapy can cost £7,000.
When cancers develop in the body, immune cells often start to fight them. Many are kept in check. But cancers mutate as they grow and immune cells can lose sight of their targets. To make matters worse, they have developed their own defences, which effectively neutralise attacking immune cells.
In 2010, a drug called ipilimumab became the first to extend the lives of patients with advanced, metastatic melanoma. It works by blocking the signals cancers use to switch immune cells off. Scientists say the drug works by taking the brakes off the immune system. Read more