Article type: Cutting Edge
Axel Ullrich is openly tipping immunotherapy as the most likely field for the next major breakthrough in cancer – “Only the immune system is so clever that it can track down a cancer cell wherever it is in the body”
A COMPELLING CONCEPT
Therapeutic cancer vaccines are all about equipping the patient’s own immune system to fight their cancer. It is a compelling concept on many fronts. On the risk-benefit front, vaccines are not associated with the sort of side-effects that make a patient’s life miserable and put their long-term health and quality of life at risk – a big plus.
On the scientific front, after millions of years of evolution the immune system has more than a few sophisticated tricks up its sleeve...
Impatient investors
Unlike most cytotoxic and cytostatic drugs, therapies that involve reprogramming a body’s immune system and sending it into action need a bit of time to take effect. Dalgleish believes his prostate cancer vaccine Onyvax could have beaten Provenge to the market had the investors held on for survival figures rather than pulling the plug at nine months, when no real difference had emerged between the vaccine and control arms. “Dendreon [manufacturers of Provenge], who had the same good results as we did in a small group, also had nothing at nine months when they did the randomised study. But they had deep pockets, and they kept going. And between 9 and 12 months the survival curve starts splitting in favour of the vaccine.” This is a pattern, he adds, that has also emerged from a number of recent lung cancer trials: “I think you can almost superimpose the survival graphs.” So this is another lesson. “Especially in the randomised studies, you don’t get the earlier split you get in the phase II studies.”
