Also known as Ziihera, the antibody treatment targets a protein called HER2, which stimulates tumour growth. It works by activating the immune system to eliminate cancer cells and reduces HER2 levels Get the free Morning Headlines email for news from our reporters across the world Sign up to our free Morning Headlines email Sign up to our free Morning Headlines email Email * SIGN UP I would like to be emailed about offers, events and updates from The Independent. Read our Privacy notice A life-