Human stem cell tests could be near

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NEW YORK (CNNMoney.com) -- The first experiments using human embryonic stem cells in human subjects could begin within a few months, the chief executive of biotech Geron said Monday.

At the annual BIO CEO conference in New York, Dr. Thomas Okarma said Geron plans to start embryonic stem-cell studies in humans with spinal cord injuries toward the end of the second quarter. Okarma said the tests would involve up to 40 human patients, while all prior tests involved rats.

This assumes that the Food and Drug Administration gives Geron a green light to proceed with the human test. Okarma said the FDA will set a "high bar" in regulating this new type of science.

Ren Benjamin, analyst for Rodman & Renshaw, believes the regulatory process could be time-consuming, because it's unprecedented.

"This is the first time that a human embryonic stem cell application is being submitted to the FDA, so there's a good chance that some questions will arise," he said.

Geron (GERN), based in Menlo Park, Calif., is also in early-stage studies with stem cell-based drugs for diabetes and heart failure. All of these experimental treatments are years away from potentially entering the market.

Advanced Cell Technology Inc. and Novocell Inc. also use human embryonic stem cells, but Geron is the only one of the these companies that's traded on the Nasdaq. Advanced Cell plans to begin testing in humans this year, but Novocell is further behind.

Neuralstem (CUR) uses stem cells from aborted fetuses to research potential treatments for spinal cord injuries. Like Geron and Advanced Cell Technology, Neuralstem plans to begin testing in humans this year, assuming that the FDA gives it the go-ahead.

Cytori Therapeutics (CYTX) and Osiris Therapeutics (OSIR) use stem cells taken from adult human tissue, which insulates from the controversy surrounding the use of human embryonic stem cells, which are obtained through in vitro fertilization.

Human-based embryonic stem cells are prized by researchers for their ability to regenerate quickly and morph into different types of cells. Supporters believe their use could someday help people with spinal injuries walk again or cure patients with degenerative diseases like Alzheimer's and Parkinson's.

But the pro-life contingent, including President Bush, opposes using human-derived stem cells, on the grounds that it creates embryos only to destroy them. Supporters of the science dispute that notion, saying that the blastocysts used as stem cell sources would be thrown out as medical waste if they weren't used in research.

In 2001, President Bush limited federal funding for human-derived stem cells to only those lines that existed at the time. In 2007, he vetoed a Congressional bill to lift those restrictions.

But in November, scientists unveiled a new type of experimental technology on Nov. 21 that sent Geron's stock into a volatile tailspin. Research teams from the University of Wisconsin in Madison and the University of Kyoto in Japan separately announced that they'd "reprogrammed" adult cells to act like embryonic stem cells.

Geron's stock has fallen more than 40 percent since then, though Okarma shrugged off the potential threat of reprogramming because it's still in the infantile stages.

"The natural human embryonic stem cell is the gold standard and we have yet to see anything else come close," Okarma said at the BIO CEO conference Monday.

But Benjamin of Rodman & Renshaw doesn't believe reprogramming poses an immediate threat to Geron.

"I think [reprogramming] is very intriguing and has a lot of potential, but it's at a nascent stage that I consider more noise than anything else," said Benjamin.

Mark Gross, a physics professor at California State University who was attending the BIO CEO conference as a potential investor, agreed that reprogramming technology is in too early of a stage to threaten Geron.

"[Reprogramming] is promising, but these things take time and we don't know which path will lead to fruition and which will lead to a dead end," he said.