Cytori Therapeutics thinks your fat can save your life. The San Diego biotechnology company has come up with a method for isolating stem cells from a patient's fat so they can be reinjected and grow into healthy tissue. Cytori's groundbreaking Celution System, expected to begin clinical trials in humans next year, could be used to treat life-threatening ailments, such as ischemic heart disease, a restriction of blood flow to the heart.
As with any unproven medical treatment, lots of questions surround the effectiveness and safety of the Celution device, but Cytori is already attracting a good deal of attention -- from investors and would-be partners alike. The company's shares, traded on the Frankfurt stock exchange, are trading around 7 euros (about $8.25) as of Nov. 29. That's up from 1.80 euros ($2.10) in January -- a pretty impressive jump for a biotech company whose flagship product has yet to enter clinical trials.
What's driving the enthusiasm? Stem cells are cells that can develop into a variety of different tissues, and they've shown effectiveness or promise in the treatment of a range of diseases. Cytori's method for isolating the cells stands out in key ways.
VANITY FACTOR. First, the company uses adult stem cells. That lets Cytori sidestep objections from social conservatives who oppose the use of stem cells derived from human embryos. Adult stem cells derived from bone marrow have already been used to successfully treat illnesses such as leukemia. Also, because Cytori's process reinjects a patient's own cells, there's less concern the patient will suffer the side effects sometimes associated with rejecting foreign tissue.
Then there's the vanity factor. "Everyone's willing to give up a little fat these days," says Cytori CEO Christopher Calhoun. And while the Food & Drug Administration currently doesn't approve the use of stem cells extracted from fat, or adipose, tissue, these cells have been used abroad to repair bone injuries. What's more, unlike many stem-cell companies, Cytori offers a relatively quick and straightforward procedure that can easily be explained to a patient.
Here's how it works: After the fat is sucked out with a liposuction-like procedure, Cytori's Celution device separates the stem cells from the bulk of the tissue. Within an hour of the removal, the patient receives an injection of his or her own concentrated stem cells.
PRIMING THE PUMP. This autumn, Cytori presented preclinical data demonstrating that after suffering heart attacks, pigs injected with their own adipose stem cells showed improvements over a control group. Calhoun says after a few weeks the treated pigs had more healthy cardiac muscle. "Whether it was newly created tissue or salvaged tissue we can't say yet," he says. "But the tissue was there."
The study also found that the test groups' hearts pumped blood more efficiently than those of the untreated animals. Because the procedure is quick, Calhoun argues that Celution is better equipped to treat the more dangerous acute cardiac episodes than other developing stem-cell treatments, which require the cells to be cultivated for days or weeks outside the body.
Still, the Celution device has a lot of clinical ground to cover. Even in a best-case scenario, it may be three to five years before the method wins FDA approval, Calhoun says. Generally speaking, that's a little longer than it takes to win approval for a new medical device, but less than for a new drug.
BRED IN THE BONE. What's more, Cytori isn't alone in trying to harness stem cells. Geron and Aastrom Biosciences have their own takes on stem cells, says Reni Benjamin, a senior biotechnology analyst at Rodman & Renshaw. His firm has a banking relationship with both. Geron uses embryonic stem cells, while Aastrom is enrolling patients for clinical trials with a procedure that uses adult cells extracted from bone marrow to treat peripheral limb ischemia.
In Aastrom's case, extracting stem cells from marrow is arguably more invasive than culling them from fat, and the company must then cultivate them at a lab. Still, bone marrow stem cells have a proven record of treating human disease, Benjamin notes. And since the favorable preclinical results touted by Geron and Cytori reflect animal studies, they should be taken with caution: Successful results in animals don't necessarily translate into effective human treatment, Benjamin says.
Cytori has taken an unusual route to stem cells. Founded in 1996 as MacroPore Biosurgery, it went public in 2000 on the Frankfurt stock exchange. At the time, its primary offerings were orthopedic implants designed to aid healing bones. These orthopedic and newer spinal implants are distributed by device company Medtronic (MDT) and they still account for most of Cytori's revenue, projected by Calhoun at between $6 million and $9 million this year.
FAT DEPOSITS. Cytori branched into new fields of medicine in 2002, acquiring StemSource, a company founded by UCLA professor Mark Hedrick, who discovered stem cells in fat tissue. Hedrick is now company president.
Despite the uncertainty of the approval process, outsiders see promise in Cytori. In November, it signed a joint venture agreement with Olympus (the camera maker also has medical-device businesses). Under the agreement, the companies are forming a joint venture that will manufacture future Celution products. Olympus also will take a stake in Cytori and has agreed to make an additional payment based on a predetermined milestone in the device's development. Cytori plans to list on Nasdaq soon.
Should the Celution be approved, it might be a chance for Cytori to push a service no one ever expected to want: fat banking. Already on offer, it's almost a novelty since there are no approved uses for the cells. Should Celution or adipose stem cells come into favor, that could change.
Younger fat, Calhoun says, has a higher concentration of stem cells and could be more effective than fat harvested later in life. Stored in a bank or in a body, these stem cells could introduce a new rationalization for rich holiday meals -- particularly for the younger of the species. It's not often that overindulgence could also turn out to be good for you.
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Halperin is a reporter for BusinessWeek.com in New York
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