In 2010, the Dendreon company received the news it had been hoping for: the US Food and Drug Administration had approved its therapeutic cancer vaccine Provenge for prostate cancer. At the time of Provenge’s approval, the headlines hailed it as groundbreaking, and they noted a surge in the price of Dendreon’s stock as the company announced its $93,000 price tag for the therapy. But enthusiasm fizzled when the company later revealed that fewer people used the therapy than expected, and in November 2014 the company filed for bankruptcy.Now, however, there is a new infusion of interest in cancer vaccines. The main difference between current and earlier vaccines is the use of a different type of antigen. “Up until recently, the major effort has been on tumor-associated antigens—shared antigens that are expressed in both tumors and normal cells,” says Robert Schreiber, a cancer immunologist at Washington University in St. Louis. “But the fact is, those antigens have been present in the host since birth.” This means that the immune system has developed a tolerance to them, which makes it “an uphill battle” to use them to elicit a therapeutic response.
[Read the story at Nature Medicine // February 4, 2016]