Prostate cancer vaccine shows promise in trial

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Shares in Cell Genesys of South San Francisco shot up nearly 20 percentage Friday after the company released a advantageous analysis of its experimental prostate gland malignant neoplastic disease vaccine GVAX.

The new information made public at a malignant neoplastic disease meeting in San Francisco propose that GVAX may lengthen endurance modern times in at least a section of patients, according to the consequences of a little clinical trial. A more-definitive answer on GVAX effectivity will only come up from consequences of much bigger trials expected in 2009.

But the company's analysis of a subset of individual responses was enough to hike its share terms to $2.36, up 39 cents or 19.8 percent.

The terms leap was another rise in the rollercoaster journeying of companies trying to develop the first malignant neoplastic disease vaccines, a drug class that raised intense involvement in springtime when Cell Genesys' challenger Dendreon of Seattle seemed close to winning Food and Drug Administration blessing for its experimental prostate gland malignant neoplastic disease vaccine Provenge.

Shares in both companies soared in April, when an Food and Drug Administration advisory panel gave Provenge a positive review. The success of any company's malignant neoplastic disease vaccine be givens to assist its rivals, because it hikes assurance in the full technological approach. But shares in both Dendreon and Cell Genesys plunged in May, when the Food and Drug Administration demanded additional cogent evidence of Provenge's effectivity and postponed its determination on approval.

Dendreon may be able to present more than grounds to the Food and Drug Administration later this year. In the meantime, both companies enjoyed a stock waver this hebdomad based on encouraging marks mined from past studies. In both cases, the companies reported a correlativity between longer endurance modern times and vaccine activity on the immune system. Manufacturers prefer to name the experimental drugs "cancer immunotherapies," because they are designed to excite the body's ain immune system to struggle cancer.

Cell Genesys reported that 34 topics among 65 evaluated had responded to GVAX by producing a specific antibody. The median value endurance clip of those 34 topics was 43 months, compared with 21 calendar calendar months among those who didn't bring forth the same antibody.

McAdams Willard Huntington Wright Ragen analyst Alice Paul Latta said such as correlativities impart assurance that a treatment actually acts upon the organic structure as it was designed to. But it could turn out that the positive consequence was owed to other factors, he said.

"The large kahuna is still out there - the existent consequences from a polar trial." Neither Latta nor his house studies fiscal neckties to Cell Genesys or Dendreon.

Dendreon shares rose 17 percentage to $6.17 Thursday based on a subset analysis of a Provenge trial. The shares dropped back to $5.87 on Friday.

Latta said terms of the low-value shares will go on their volatile swings as the companies race each other to win the first blessing for a malignant neoplastic disease vaccine.

"These pillory probably have got the peak ratio of investor attending to marketplace cap of any pillory I know," he said.

E-mail Bernadette Tansey at .