(RxWiki News) Inflammatory bowel diseases are usually treated by suppressing the immune system. But a weakened immune system can put patients at risk for other health problems. A new treatment being tested may be effective and have fewer negative effects than current therapies.
Vedolizumab is a protein that prevents immune cells from destroying the lining of the gut, which is the main cause of inflammatory bowel disease.
These two studies found that vedolizumab worked in patients for whom other therapies have failed.
"Ask your gastroenterologist about new treatments for inflammatory bowel disease."
These studies were conducted by Brian Feagan, MD, professor of medicine and epidemiology at Western University in London, Canada, along with colleagues.
The aim of the two studies was to find out the effectiveness of vedolizumab, a new medication for the treatment of ulcerative colitis and Crohn’s disease.
Ulcerative colitis and Crohn’s disease are two common forms of inflammatory bowel disease. With these conditions, a person’s immune system kills their own gut cells, which can lead to symptoms such as blood in the stools, diarrhea and weight loss.
Usually, inflammatory bowel diseases are treated by suppressing the immune system. But this may lead to unwanted effects such as pneumonia, skin infections and blood infections because the immune system cannot defend the body as well as it normal can.
According to the studies, vedolizumab acts by blocking the action of immune cells in the gut but does not affect the rest of the body. This may help avoid the unintended side effects that occur when the entire immune system is suppressed.
Two different studies were conducted to assess the effect of vedolizumab on ulcerative colitis and Crohn’s disease patients.
A total of 895 patients were recruited for the ulcerative colitis study and 1,115 patients were recruited for the Crohn’s disease study. These patients had been unsuccessfully treated with other medications, including steroids, medications that suppress the immune system and/or antibiotics.
In each study, the patients initially received either two doses of vedolizumab or two doses of a blank injection with no medication (placebo). Patients who responded to the initial treatment with vedolizumab were randomly divided into two groups: one group received vedolizumab and the other received a placebo.
Response to the treatment of ulcerative colitis was measured by looking at the Mayo Clinic score, which ranges from 0 to 12, with higher scores indicating more active disease. Patients who had a reduction of at least 3 points and also at least a 30 percent reduction compared to the score measured at the beginning of the study were considered responsive to treatment. The response also included an accompanying reduction in rectal bleeding.
For patients with ulcerative colitis, initial response rates after six weeks of treatment were 47.1 percent among those who took vedolizumab and 25.5 percent among patients who were given a placebo.
After 52 weeks, 41.8 percent of patients who continued to receive vedolizumab every eight weeks remained in remission as compared to a 15.9 percent response rate for those who switched to placebo by that time point.
In the study that looked at Crohn’s disease patients, response rates were measured using an index called Crohn’s Disease Activity Index (range from 0 to 600 with higher scores indicating more severe disease). Patients who had an index equal to or higher than 150 following treatment were considered responsive to treatment.
For patients with Crohn’s disease, initial response rates at week 6 of treatment were 14.5 percent for those who received vedolizumab and 6.8 percent for those who received a placebo.
Among those who responded initially, further treatment with vedolizumab resulted in clinical remission for 39 percent (treatment every 8 weeks) and 36.4 percent (treatment every 4 weeks) compared to clinical remission in 21.6 percent among those given a placebo.
According to gastroenterologist Dr. Maxwell Chait, MD, FACP, of ColumbiaDoctors Medical Group, "In ulcerative colitis, the inflammation is much more superficial than in Crohn's disease. The difference in response between the two may lie in the fact that Crohn's is a more extensive disorder."
The frequency of adverse events (negative side effects) was similar in the vedolizumab and placebo groups in the case of ulcerative colitis patients.
For Crohn’s disease patients, side effects such as inflammation of the nose and throat and infections occurred more frequently in the vedolizumab group than in the placebo group.
Overall, the two studies found that patient outcomes with vedolizumab were better than treatment with a placebo.
The researchers concluded that vedolizumab is an effective treatment for those suffering from ulcerative colitis and Crohn's disease when other treatments have failed.
"The publication of these study findings are important since the results support the potential for vedolizumab, if approved, to help manage symptoms in some patients for whom previous treatments have failed," said Dr. Brian Feagan.
A medication can be launched in the market only after it is approved by the FDA after a series of clinical trials are conducted by the company that makes the medication.
It is important to note that vedolizumab is undergoing clinical trials, which means it is not yet available to the general patient population.
"It is likely that vedolizumab will become part of the growing armamentarium of new drugs available for the treatment of inflammatory bowel disease, particularly in patients who did not have a response to previous treatment," said Dr. Chait, who was not associated with the study.
The results of these studies were published in the August 22 issue of The New England Journal of Medicine.
The research was funded by Millennium Pharmaceuticals, a wholly owned subsidiary of Takeda Pharmaceutical Company Limited, the largest pharmaceutical company in Japan. The lead author and many other study authors reported consulting relationships with various pharmaceutical companies.