One of the more common autoimmune diseases, Sjögren’s syndrome affects as many as 0.5 to 2 percent of Americans. Several medications currently exist to address its symptoms, and there are self-care strategies to make you feel better in the short term, but researchers are eager to find new, more effective treatments. Research in Sjögren’s syndrome aims to pinpoint its possible causes, as well as ways to cure the troubling, drying syndrome that affects mucous membrane tissue, especially the eyes, mouth, skin and vagina.

Drug Approaches in Development

The most fertile ground for research and development of new drug treatments for Sjögren’s syndrome seems to be Asia. Several treatments are being studied there, some showing promising results to treat dry eye and dry mouth associated with the disease:

Mizoribine (Bredinin), an immunosuppressant drug, one designed to quiet an overactive immune system, is available only in Japan and China at this time. One Japanese study published in the English medical journal Rheumatology showed positive results in improving malfunctioning salivary glands in some Sjögren’s patients, but was less effective in those subjects with a condition called intralobular fibrosis – an excessive growth of connective tissue on the lobes of organs.

Mycophenolate sodium (Myfortic), an immunosuppressant drug already used as a treatment to prevent organ rejection in transplant recipients, is being studied in a number of autoimmune, arthritis-related diseases, including Sjögren’s syndrome. One German trial showed the drug helped a small group of Sjögren’s patients, improving their dry eye symptoms and reducing their need for eye drops. In addition, at the end of the trial, their blood showed reduced levels of rheumatoid factor and other agents that signal inflammation.

Nizatidine (Tazac, Axid), an oral H2 blocker drug used commonly to treat excess stomach acid, is also being studied in Sjögren’s syndrome as a way to treat xerostomia, or oral dryness. A Japanese study compared nizatidine to famotidine (Pepcid) to determine if the drugs would relieve dry mouth. Nizatidine improved dry mouth, although famotidine did not. The study also showed that those who took nizatidine had mild improvement in related symptoms: the ability to chew, swallow and taste food.

Rebamipide (Mucosta), a mucosal protective agent, is currently in Phase II trials in the U.S. Approved in Japan, it is taken as a pill and is being studied for treating dry eye and mouth. Japanese researchers studied rebamipide in mice with Sjögren’s syndrome in 2008, and the drug showed effectiveness in treating sicca, or dryness, symptoms. After treatment, saliva production increased and the development of autoimmune-related lesions was prevented. Another Japanese study conducted in 2009 showed similarly positive results in boosting saliva production, and showed no difference in adverse effects between people taking the drug and taking a placebo, showing the drug is safe.

Targeting B Cells

Other research efforts delve into the possible roots of Sjögren’s syndrome. What factors cause the body’s immune system to malfunction and attack glands, drying body tissues?

A recent Dutch study published earlier this year showed that development of targeted biologic therapies for Sjögren’s must attack B cells – a type of lymphocyte, or white blood cell. The researchers reported that depletion of B cells likely leads to the restoration of saliva production, and helps treat other, non-gland-related problems associated with Sjögren’s syndrome, such as skin disorders or neurological problems. New biologic drugs developed to target these cells should be studied further, the researchers note.

In addition, a group of Swedish researchers presented findings from a study at the American College of Rheumatology’s (ACR) November 2010 annual meeting showing that people with Sjögren’s syndrome had skewed B cell maturation after receiving the H1N1 flu vaccine, resulting in higher amounts of vaccine-specific antibodies that may be related to inflammation. While the patients developed immunity against the flu, the study may reveal some links between B cells and autoimmune problems in Sjögren’s syndrome.

Genetic cues: A group of researchers at the National Institutes of Health in Bethesda, MD, reported on their study focusing on better ways to diagnose Sjögren’s, including identifying microRNAs, or genes, that may be related to the disease. The researchers used biopsies, or tissue sample studies, from salivary glands. The study showed promising results in identifying a genetic biomarker for the disease, aiding its proper diagnosis so treatment can begin promptly.

Gene therapy: Gene therapy is one of the most exciting areas of disease research, where targeted molecules are inserted into patients’ genetic tissue in an effort to correct malfunctions that cause disease. At the ACR 2010 meeting, a group of Dutch researchers reported the findings of their gene therapy study targeting B cells in mice. The researchers used B cell-targeting gene therapy to treat the salivary glands of mice, and found that they were able to reduce autoimmune-related inflammation. They believed their findings suggested that such gene therapy would aid people with Sjögren’s syndrome.

Another study conducted at the University of Florida investigated delivering Small Interfering RNA genetic material, or siRNA, into cells in the lab, a process that showed promising results in preventing inflammatory reactions. The researchers stressed that this therapeutic strategy could be easily manipulated to target different genes, and could have potential as a Sjögren’s treatment.

Artificial salivary glands: Researchers are trying to develop artificial or regenerated salivary glands to help people with Sjögren’s syndrome relieve dry mouth symptoms. Scientists are experimenting with tissue engineering, gene therapy-like techniques, and stem-cell methods to help malfunctioning salivary glands start producing the half-liter of saliva needed daily to prevent oral disease.