By Steven Reinberg
The European study also found that for patients who cannot undergo surgery for the condition, stem cell transplants resulted in serious side effects, including infections.
"In this group of the most resistant cases of Crohn's disease, stem cell transplant was an effective treatment, but it is not a miracle cure that could be applied to anyone with Crohn's disease, because it only seems to work in a minority of patients and the treatment is challenging and hazardous," said lead researcher Christopher Hawkey. He is a professor of gastroenterology at Queen's Medical Centre in Nottingham, England.
For the study, Hawkey and colleagues randomly assigned 45 patients with Crohn's disease to transplants with their own stem cells or to continued standard medical care. Patients were followed for one year.
Crohn's disease is a chronic inflammatory condition of the intestinal tract that produces symptoms such as persistent diarrhea, rectal bleeding and painful cramps, according to the Crohn's & Colitis Foundation of America. The condition can cause lifelong ill health, impaired quality of life and reduced lifespan.
Immunosuppressive drugs are the standard of care, but some patients do not respond to them or stop responding, Hawkey said.
Stem cell transplants represent an attempt to reset the immune system, which turns on itself in Crohn's disease, Hawkey explained.
"The stem cell treatment involves wiping out the body's immune system and replacing it with the patient's own innocent stem cells, a sort of immunological spring clean," he said.
The report was published Dec. 15 in the Journal of the American Medical Association.
One year after treatment, the researchers found no statistically significant difference between the groups in the proportion of patients whose disease was in remission in the past three months -- just two in the transplant group and only one receiving standard care.
But 61 percent in the transplant group had been able to discontinue active treatment in the past three months compared with 23 percent in the usual care group, the researchers said.
In all, 76 serious adverse events occurred in transplant patients -- mostly infections -- versus 38 in the usual care group. And one transplant patient died, Hawkey said.
"Stem cell transplantation is probably the most effective treatment for Crohn's disease, but also the most toxic," he said. "It cannot be recommended for widespread use at the present time but may be a risk worth taking for a small number of patients who have run out of treatment options."
The challenge now, Hawkey added, is to find ways to identify those most likely to benefit and those who will not.
However, the Crohn's & Colitis Foundation of America is more cautious.
"At this time, we are not certain that the benefits of stem cell transplants in Crohn's disease patients outweigh the risks," the foundation says in a policy statement.
Stem cell transplants are not a cure, and patients are still genetically predisposed to redevelop Crohn's disease, the foundation says. It notes that transplant patients are also at risk of adverse events, including infection, because the patient's immune system is severely compromised for several weeks.
The study authors recommend further research to assess the value of maintenance immunosuppressive therapy alongside stem cell transplant.