Geron Shares Soar on News of Cancer Vaccine Research

Shares of Geron Corp. jumped 19% on Wednesday after research on mice suggested a vaccine based on an enzyme studied by the company might work against a range of cancers.

Menlo Park, Calif.-based Geron, which has specialized in the study of the enzyme telomerase, rose $5.44 to close at $34.31 in heavy trading on Nasdaq.

“Telomerase is expressed in most human tumors, but it is not present in most normal tissue. This suggests that it could be used as a generalized target,” said Jane Lebowski, vice president of cell and gene therapy at Geron.

The researchers, from Duke University and Geron, cautioned that their findings have yet to be tested in humans.

Lebowski said Geron is planning to begin trials of the vaccine in humans within a year or two and, if all goes smoothly, could have an actual vaccine in four to seven years.

The research, reported in the journal Nature Medicine after the close of trading Tuesday, found that an active part of the enzyme can stimulate development of immune cells that can kill several kinds of mouse and human cancers.

Such a vaccine, if developed for humans, would be a “therapeutic” vaccine, meaning it would not prevent cancer but instead would prompt the body’s immune system to fight existing tumors.

“This is potentially quite exciting, but most of the work they’re talking about is preclinical--done only in mice--so you can’t get too excited,” said Alan Auerbach, an analyst at First Security Van Kasper.

Geron has specialized in the study of telomerase since earlier studies indicated the enzyme appeared to be present in unusually high amounts in many types of cancer cells.

In the first half of this year, Geron reported a net loss of $25 million on operating revenue of $3 million, compared with a loss of $31.4 million and revenue of $2.8 million a year ago.