Cancer cure - Keytruda wins Ron Walker's war on cancer
Keytruda is an immunotherapy drug, like Yervoy, which co-opts the body's
immune system into recognising, attacking and destroying cancer cells.
It acts in a different way to Yervoy; Keytruda blocks a molecule called
PD-1. "The cancer is very clever. It puts out this molecule PD-1 and
turns off the body's immune response so it can survive and stop the
immune system from attacking it," says McArthur. Keytruda specifically
disrupts that molecular interaction. "We still have to stop and take a
breath at how it could be this relatively simple," says McArthur. "We
are very surprised. This is the biggest breakthrough we've had."