Aug. 15, 2012 -- A pill that targets the very early stages of the body’s immune response may ease the symptoms of ulcerative colitis.
The drug is called tofacitinib. It's up for FDA consideration to treat another condition -- rheumatoid arthritis.
In a new study, researchers tested the drug in people with ulcerative colitis. Up to 78% of those who took the experimental drug saw a significant improvement in their symptoms and up to 41% had their disease go into remission.
Ulcerative colitis is a chronic inflammatory disease that affects the large intestine or colon and rectum. It causes periodic bouts of inflammation that lead to symptoms including abdominal pain, bleeding of the rectum, and diarrhea.
The cause of ulcerative colitis is unknown, but it is thought to be triggered by an abnormal immune response.
Several drugs already treat ulcerative colitis, but researchers say more are needed because none is universally effective and many have serious side effects.
New Approach in Treating Inflammatory Disease
Unlike most biologic drugs used to treat inflammatory diseases such as ulcerative colitis, tofacitinib targets reactions earlier in the immune response, so it has broader effects in the body.
That can make the drug more effective in treating disease as well as raise the potential for side effects.
Also, unlike biologic drugs that must be given via injections and intravenous infusions, tofacitinib comes in pill form, which makes it easier to use.
Tofacitinib works by blocking Janus kinase (JAK) enzymes within cells. These enzymes help control the chemical messengers involved in the immune response in inflammatory diseases such as ulcerative colitis and rheumatoid arthritis.
Tofacitinib for Ulcerative Colitis
The new study tested four doses of the drug in 194 adults with moderate to severe ulcerative colitis, most of whom had not responded well to conventional therapies.
They got the drug or a placebo twice a day, in pill form, for eight weeks.
These results, published in the New England Journal of Medicine, showed that 78% of people who got the highest test dose of the drug had their ulcerative colitis symptoms improve, compared to 42% of those who took the placebo.
Remission was also more common with the drug: 41% of people who took the highest dose of tofacitinib experienced a remission of their disease compared with 10% on the placebo.
Side Effects Need Further Study
Cholesterol levels rose in tandem with the drug dose (higher doses were linked to a greater increase in cholesterol levels). That effect went away after people stopped taking the drug.
During the study, three people taking tofacitinib also had a drop in their white blood cell count. White blood cells help fight infection. In the study, the most commonly reported infections among people taking the drug were flu and cold.
The researchers say further studies are needed to check on the safety and effectiveness of tofacitinib in treating ulcerative colitis and to understand its effects on cholesterol levels and infection risk.
The study was funded by Pfizer, which makes tofacitinib.