During the next few months, doctors at three U.S. hospitals are expected to begin giving breast cancer patients who have undergone chemotherapy infusions of an experimental cell-based solution in the hope of restoring the vigor of the patients' bone marrow and immune systems.
The new drug, Stromagen, made by Baltimore-based Osiris Therapeutics Inc., is an outgrowth of research efforts to regenerate diseased and damaged body parts using "master" cells, known as stem cells, which give rise to other more specialized cells in the body.
A growing number of biologists and biotechnology executives believe that over the next five to 10 years an array of new stem cell-based therapies, already used to reinvigorate blood weakened by some cancer treatments, will become commercially available for treating a range of ailments, from torn knee cartilage to brain neurons ravaged by Parkinson's disease.
These master cells, which until just a few years ago were not well understood, are giving rise to an industry, with Maryland companies playing prominent roles.
"The age of regenerative medicine is really on the doorstep," said Daniel Marshak, Osiris' chief scientist.
Richard Garr, co-founder and chief executive officer of privately held NeuralSTEM Biopharmaceuticals Inc. in College Park, agrees. "I believe in the next five to 10 years we'll see stem cells used as a routine first-line therapy for connective and structural tissue problems, [blood] treatments, and Parkinson's," he said.
Stem cell treatments for Alzheimer's disease, stroke and other central nervous system, or CNS, disorders will "certainly" be in human trials, Garr predicts.
Implanting stem cells to regener- ate neurons in the brain may sound like science fiction.
But it's not as far-fetched as it may seem. Swedish scientists have already implanted primary fetal tissue in a small group of Parkinson's patients, and report that they appear to be doing remarkably well.
"They did before and after films and the difference is really amazing," said Garr, who has seen the footage.
Dr. John Gearhart, a genetics and stem cell expert at the Johns Hopkins University School of Medicine, agrees that the optimism is not unfounded. Research in the field is moving "very rapidly," said Gearhart.
Breakthroughs in the past year have made a once-obscure niche of scientific inquiry a topic of discussion in the boardrooms of pharmaceutical companies, say experts.
"Pharmaceutical companies no longer are regarding stem cell research as a marginal activity," said Christine Copple, NeuralSTEM's chief operating officer. "There is now this halo around stem cell technology. Drug companies clearly see the market potential."
By some company experts' reckoning, that market potential is vast for stem cell-based treatments, dubbed "liveware" by some in the industry.
James S. Burns, Osiris' chief executive officer, estimates the potential for bone, cartilage and other connective-structural stem cell treatments to be $15 billion worldwide.
NeuralSTEM's Copple believes that effective stem cell-based treatments for neuro-degenerative diseases, such as Parkinson's, are also multibillion-dollar markets.
For now, the only stem cell treatment on the market is a blood-filtering device marketed by Baxter International Inc. to treat cancer-related transplant patients. Analysts estimate that it could yield $200 million annually. The device is based on work by Hopkins oncologist Curt Civin, who came up with the idea of filtering out healthy stem cells for reinfusion.
Future commercially available stem cell treatments should yield "rather significant" medical benefits too, predicts Gearhart, though experts caution that a number of hurdles remain.
The emerging industry got a jump-start in November with announcements by Gearhart and his Hopkins team and another team at the University of Wisconsin that they had been able to isolate and grow in the laboratory stem cells taken from human embryos.
The breakthrough was considered significant because such stem cells are thought to have the ability to divide without limit and give rise to virtually any type of human cell.
That might have huge implications for growing replacement tissues for organ transplantation, controlling diabetes, and a host of other conditions, say experts.
Then just this month, Osiris scientists disclosed in Science magazine that they had been able to isolate and grow stem cells from bone marrow samples taken from adult donors and then manipulate those cells to grow or "differentiate" into three specific types of cells: bone, cartilage and fat. Marshak said Osiris believes that it can replicate the success with muscle, tendon and other structural and connective tissues.
The company, he said, hopes to be able to seek Food and Drug Administration approval soon for human tests that will attempt to regenerate bone and cartilage damaged by orthopedic injuries and osteoarthritis.
Until the embryonic stem cell breakthrough, scientists had been able to work only with stem cells that could give rise to certain cell families: mesenchymal stem cells, the type Osiris is working on, which develop into structural and connective tissues; hematopoeitic stem cells, which develop into red and white blood cells and other blood components; and neuronal stem cells, which build the central nervous system.
Scientists believe three to four other master types may exist, but they remain undiscovered.
The emerging industry is not without controversy. Gearhart and the Wisconsin team's breakthrough generated a storm of debate from critics opposed to using tissue samples taken from frozen embryos about to be destroyed.
The National Institutes of Health, the chief funding agency for medical research, said in a statement this year that advancements in isolating and culturing such cells in the laboratory "bring biomedical science to the edge of a new frontier that is extraordinarily promising."
But NIH funding for embryonic stem cell research has been bogged down in the ensuing ethical and legal debate. The NIH is attempting to develop strict guidelines governing embryonic research and whether to fund it.
Osris' Stromagen drug treats bone marrow. It is derived from biopsies of patients' own cells before chemotherapy. The privately held company also is developing Allogen, a similar treatment that would be more universal: Donor bone marrow cells would be frozen for later matching with cancer patients.
The company also hopes to move into clinical trials several treatments for the orthopedic market. "We expect to have a steady stream of product candidates coming out over the next several years," said Burns. "We're not going to be a one-product company."
NeuralSTEM, launched in 1995 by Garr and NIH scientists, is using human neural stem cells to develop new cell-based products that drug companies could use to screen experimental drugs.
The company, based at the Technology Advancement Program Center at the University of Maryland, also is developing an injectable cell-based solution to regenerate neurons in the brains of Parkinson's patients. Garr estimates that human trials of that treatment are 12 to 18 months away. From there the company hopes to develop stem cell treatments for Alzheimer's disease, stroke, and injury-induced epilepsy.
The company, said Copple, is also trying to use stem cells as a way to deliver or implant drugs into the brain, one of the body's toughest region's for getting drugs to because of what's known as the "blood-brain barrier."
Gryphon Inc., a company partly owned by Osiris, is developing blood stem cell treatments for blood disorders. It has an agreement with Hopkins blood stem cell researcher Civin.
In addition, Geron Corp., a Menlo Park, Calif., biotechnology company attempting to develop tissue for transplant medicine and other treatments from embryonic stem cells, has a research agreement with Gearhart at Hopkins. Geron executives said they don't expect any product candidates for years.
Nationwide other new companies are pursuing their own product development efforts. Among them: Advanced Cell Therapeutics Inc. in Worcester, Mass., which is also working on embryonic stem cells as a potential source for regenerative treatments, and Diacrin Inc. of Charlestown, Mass., which is using fetal pig cells in an experiment to treat Parkinson's.
Osiris has a multimillion-dollar research and royalty licensing deal with Swiss drug giant Novartis AG for stem cell treatments approved for treating bone and cartilage injuries and disease. Burns said the company expects to sign another major pharmaceutical company licensing deal this year for another line of stem cell treatments.
NeuralSTEM says it's been in talks with a number of major pharmaceutical companies about a cell-based treatment it's working on for Parkinson's and using the cells to help drug companies conduct early screenings of new drugs for toxicity and effectiveness.
Said NeuralSTEM's Garr, "I think it's fair to say that when it comes to the number of products that are conceivable from stem cells, the sky's the limit."