By David Brinn
December 12, 2004
A revolutionary Israeli treatment for leukemia using a stem cell-derived product has achieved remarkable Phase I and II trial results. Ten American patients with late-stage leukemia underwent the StemEx leukemia treatment developed by start-up Gamida-Cell and 50% confounded expectations by living past the first 100 days.
It appears to be the first successful human clinical test of a commercial product derived from stem cells.
Each year, nearly 27,000 adults and more than 2,000 children in the United States learn that they have leukemia, a malignancy of the blood-forming cells in the bone marrow.
Current treatments are based mostly on bone marrow transplants. When these transplants encounter the patients' immune systems, severe side effects result. StemEx uses progenitor and stem cells taken from the patients themselves. The population of these cells is expanded, and they are then returned to the patient's body. The results of trials on the ten terminal patients upheld Gamida-Cell's expectation that the severe side effects of current treatments would be greatly reduced.
The trial was conducted at the University of Texas MD Anderson Cancer Center in Houston, one of the world's most prestigious institutes.
Gamida-Cell CEO Ehud Marom said that the trial had taken 100 days, during which the treatment on patients had been monitored. Anderson Center principal investigator Dr. Elizabeth Shpall presented the trial results last week at the 2004 annual meeting of the American Society of Hematology (ASH).
"Anderson is the best center for cancer in the U.S. and we wanted to work with the best center and the best principal investigator," Marom told ISRAEL21c.
According to Marom, until now using conventional treatment, only 10% of patients managed to get through 100 days. With the StemEx treatment, 50% of the patients whose cases were extreme - and for which no other treatment were available -survived 100 days.
"The patients included in the trial were in the advanced stages of leukemia. However, in the future, the treatment can be used instead of bone marrow for any stage patient," Marom said.
"Ten leukemia patients, many of whom had failed standard chemotherapy and other therapies, underwent StemEx transplants," explained principal investigator Shpall. "StemEx combines ex vivo expanded cord blood stem/progenitor cells with non-expanded cells from the same unit. The net results of the Phase I/II study indicate that StemEx is safe, and no serious adverse effects were reported in connection with the StemEx transplant. We are very excited about the data from this study. It is very important research that we believe will contribute greatly to patient care in the future."
According to Shpall, four standard parameters within the time frame of 100 days were evaluated. These included graft failure rate, transplant-related mortality, GvHD and time to engraftment. In all cases, StemEx scored well.
"The bodies of only 20% of the patients we treated rejected the transplant, compared with an average of 60% of current transplants. In addition, the time that patients required to rebuild their immune systems was shorter than for current treatments, which meant that they were less exposed to infections," Marom told Globes.
"The results of the Phase I and Phase II trials mean that our product is safe, and apparently effective. The company must now prepare for a more extensive Phase III trial," he added.
Marom told ISRAEL21c that Anderson would be used once again as a site for the trials, as well as a center in San Antonio, Texas, and other centers across the U.S. and possibly in Canada. He estimated that the next trials would begin in the first quarter of 2005, following the approval of the FDA to commence this part of the trial. "We are hoping for an FDA approval by 2007/2008," he said.
Gamida-Cell develops products based on stem cells for treating cancer and autoimmune diseases, and for cardiac and pancreatic repair. The company was founded in 1998 based on technology for stem cell expansion licensed from Hadassah University Medical Center in Jerusalem. The StemEx is their first product which has moved past Phase II trials.
"In the development of biotechnology companies, Gamida-Cell is now a company with a product headed for Phase III trials. If these trials are successful, the drug can be registered with the FDA and marketed," said Marom.
Gamida-Cell has raised $22 million to date from Elscint (Europe-Israel), Biomedical Investments, Teva Pharmaceutical Industries Ltd. (Nasdaq: TEVA; TASE: TEVA), Denali Ventures, Auriga Ventures, Pamot, and Comverse Technology (Nasdaq: CMVT). The company has also signed a conditional strategic agreement with Teva.
"The results of the trials have created great interest in the company on the part of large and medium-sized pharma companies, and also in the investment community. Our goal now is to bring StemEx to market as quickly as possible," said Marom. He told ISRAEL21c that news of the StemEx success was received very positively at the ASH conference, "both from the clinical as well as the big pharma perspective."
The combined market potential of Gamida-Cell's stem cell expansion products is estimated at $40 billion worldwide. This includes umbilical cord blood stem cells as well as stem cells from the placenta, bone marrow, peripheral blood and adult organs like the liver and heart in addition to skin, neural and pancreatic tissue.
Israel is among a small group of countries that have developed their own stem-cell regulations that permit most types of work in the field. Israel's carefully regulated but open atmosphere for research has helped catapult it into the front ranks of a field that many consider the next frontier of science.
Besides Gamida-Cell, other Israeli biotech companies on the cutting edge of stem cell products include Pluristem (PLRS.OB), which multiplies stem cells found in umbilical cord blood., Tissera (OTCBB:TSSR), which is developing cell therapy to treat harmed fetuses; and ProNeuron which has developed ProCord, a treatment for complete spinal cord injury.
"What Israel has done in the laboratory and in their oversight mechanisms is a model for other nations to emulate," Georgetown University's LeRoy Walters, an expert in the global dimensions of stem-cell research, told The Forward.
The work by Gamida-Cell was carried out with adult stem cells, not embryonic stem cells which is at the heart of the controversy in the United States. That debate resulted in President Bush's 2001 decision to cut off federal funding for research on stem cells harvested from human embryos.