Both drugs had shrunk the cancer tumors by at least a third in 58% of patients, with the tumors stable or shrinking for an average of 11.5 months.

The immune system is a powerful defense against infection. Cancer, which is a corrupted version of healthy tissue, can take advantage of brakes which are naturally built in to stop attacks on its own tissues and deplete the immune system.
Ipilimumab, which was approved as an advanced melanoma treatment by the UK’s health service last year, and nivolumab both take the brakes off.
Dr. James Larkin, a consultant at the Royal Marsden Hospital said, "By giving these drugs together you are effectively taking two brakes off the immune system rather than one so the immune system is able to recognise tumors it wasn’t previously recognizing and react to that and destroy them."
But the great hope is these immunotherapies will prove to be effective treatments for a wide range of cancer types.
Source-Medindia