Shares of Antigenics surged for three straight days this week after researchers released new data backing its kidney cancer vaccine Oncophage.
Investors pushed the stock straight up after hearing that patients taking Oncophage lived longer than the control arm. Oncophage is currently approved only in Russia, but shareholders clearly believe that the oncology vaccine can win much wider approval. Shares of Antigenics have soared 250 percent in the past month.
"Overall survival curves are consistent with the trends seen earlier for recurrence-free survival and support the idea that earlier-stage patients have more to gain from treatment with a cancer vaccine," noted Ren Benjamin, an analyst at Rodman & Renshaw.
But Antigenics wasn't the only vaccine developer to benefit from good data. Dynavax saw its stock jump after releasing late-stage data demonstrating that patients taking its hepatitis B vaccine needed fewer doses and responded better than patients taking Engerix-B. Researchers said that the data showed that patients over the age of 40 responded the best. And Celldex Therapeutics surged on the news that a small mid-stage study of its experimental vaccine for glioblastoma multiforme produced positive data. Pfizer paid Celldex $50 million upfront last year to partner on the vaccine.