Nobel Prize for novel cancer therapies

4 October 2018

Two of the men responsible for the discovery and development of checkpoint inhibitors, therapies that revolutionised the way metastatic melanoma patients are treated, extending lives and improving quality of life for countless patients, were awarded this year’s Nobel Prize in Physiology or Medicine.

Professor James P. Allison from MD Anderson Cancer Centre, and Professor Tasuku Honjo from Kyoto University were jointly awarded the Nobel Prize for their separate work from the early 1990’s, where they each discovered a different protein that plays a major role in regulating the immune system.

The immune system is a balancing act – it is constantly trying to fight off foreign invaders, like viruses and bacteria, without harming the body – that relies heavily on an intricate system of brakes and accelerators. Sometimes the balance is off, resulting in autoimmune diseases where the immune system attacks the body, or diseases like cancer, where the immune system does not recognise that there is anything amiss.

Both Professor Allison and Professor Honjo discovered molecules that act as a brake in the immune system, halting its action and allowing cancers to grow. In Professor Allison’s research, he showed that blocking the molecule he discovered, CTLA-4, could switch off the brake, allowing the immune system to recognise a tumour and attack it. His work lead to the development of the melanoma fighting drug ipilumimab. Professor Honjo discovered the protein PD-1, and found that blocking it allows the immune system to recognise cancer as an invader and mount an immune response. This led to the manufacture of the immunotherapies nivolumab and pembrolizumab.

Ipilumimab (Yervoy), nivolumab (Opdivo) and pembrolizumab (Keytruda) are now used extensively to treat metastatic melanoma, working to help patient’s own bodies to recognise and fight the disease. Since these treatments have become available, melanoma patients have a better prognosis than ever before.

The two men will receive their Nobel Prizes at a formal ceremony in Stockholm in December. Five different Nobel Prizes are awarded every year, with the Nobel Prize in Physiology or Medicine given to up to three people who have made outstanding discoveries in the fields of medicine or the life sciences. Previous Nobel laureates include three of the men responsible for the discovery of DNA, and the three men who discovered penicillin.