Compared to conventional therapies, hematopoietic stem cell transplantation (HSCT) doesn’t result in significant improvement in patients with difficult-to-treat (refractory) Crohn’s disease, according to a new study. Results of the randomized clinical trial were published Dec. 15 in the Journal of the American Medical Association (JAMA).
Affecting one in 200 Americans, Crohn’s disease is an inflammatory bowel disease in which an abnormal immune system response causes chronic inflammation in the digestive tract. Symptoms include persistent diarrhea, rectal bleeding and painful stomach cramps. According to the Crohn’s & Colitis Foundation, the condition can cause lifelong ill-health, impaired quality of life and reduced life span.
The standard care for Crohn’s disease is immunosuppressive drugs that help to control the immune system’s inflammatory response. However, not all patients respond to the drugs and some may experience decreased effectiveness to the medications over time.
Case reports have suggested that HSCT may benefit some patients who do not respond to immunosuppressive drugs. “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,” lead author Dr. Christopher J. Hawkey, a professor of gastroenterology at Queens Medical Centre, Nottingham, U.K., told HealthDay.
To determine if using one’s own stem cells was an effective treatment for hard-to-treat Crohn’s, Hawkey and his colleagues undertook clinical trials in 11 transplant units in six European countries from July 2007 to September 2011. The research team enrolled 45 patients aged 18 to 50 who had chronic refractory Crohn’s disease despite the use of immunosuppressive drugs or surgical treatment.
Participants were divided into two groups: 23 patients underwent HSCT immediately and 22 deferred HSCT treatment for a year. All patients received standard care as needed until the follow-up in March 2013. The hoped for result for stem cell transplantation patients was sustainable disease remission.
A year after treatment, the researchers did not find a statistically significant difference between the two groups in terms of sustainable remission – 8.7 percent in the HSCT group versus 4.5 percent in the standard-care group. However one statistically significant finding did emerge: 60.9 percent of the HSCT patients were able to stop taking immunosuppressive drugs in the last three months, compared to 22.7 percent of the non-HSCT group.
But findings also showed there were 76 adverse events – mostly infections – among the transplant patients, versus 38 in the standard-care group. One transplant patient died.
Because HSCT patients’ immune systems are severely compromised in preparation for the transplant, they are at high risk for adverse events such as infections, explained Hawkey. “Toxicity will remain the most significant barrier to HSCT in patients with Crohn’s disease,” the researchers noted in a JAMA news release.
Hawkey reinforced that notion in HealthDay. “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 options.”
The Crohn’s & Colitis Foundation, however, does not agree. In its policy statement, the organization wrote, “At this time, we are not certain that the benefits of stem cell transplants in Crohn’s disease patients outweigh the risks.” It noted that stem cell transplants are not a cure, and patients are still genetically predisposed to redevelop the disease.
The authors acknowledge that more research is needed to assess the value of stem cell transplantation. They concluded “identification of factors that predict either the risk of adverse effects or response to treatment will enhance the utility of this treatment in clinical practice.”