First NIH Clinical Trial for Interstitial Cystitis Begins Oral Drugs Studied for Painful Bladder Problem

Doctors have opened enrollment for a clinical trial of oral drugs for interstitial cystitis (IC), a persistent and often painful bladder syndrome affecting about a million people, mostly women.

The Interstitial Cystitis Clinical Trials Group will use pentosan polysulfate sodium (Elmiron) and hydroxyzine hydrochloride (Atarax) to treat 136 people who have IC and unremitting urinary frequency and pain or discomfort lasting at least 24 weeks.

Elmiron and Atarax were selected first for testing because patients prefer oral treatments and studies suggest that each drug uniquely targets different aspects of IC. In some patients, Elmiron reinforces the bladder lining, usually a barrier to urine's toxicity. Elmiron is the only oral drug approved by the Food and Drug Administration for IC. Atarax is an antihistamine that reduces the activity of mast cells, which may cause bladder inflammation and pain. The two drugs may also work synergistically, leading to quicker, more potent symptom relief.

"IC leaves many people unable to cope with basic daily functions," says Leroy M. Nyberg Jr., Ph.D., M.D., director of urology research at the National Institute of Diabetes and Digestive and Kidney Diseases, which is funding the clinical trial. "This is the first of a series of rigorous treatment trials. Our ultimate goal is to be able to recommend to physicians those therapies most likely to relieve symptoms in subgroups of patients." The cause of interstitial cystitis is unknown and no one therapy works effectively in a large number of patients. Often mistaken for a bladder infection, IC may elude diagnosis for years.

Clinical trial participants will be divided into four groups to receive either (1) a placebo, (2) Elmiron, (3) Atarax, or (4) both active drugs for 6 to 16 months, depending on when they join. At the end of the study, doctors will compare self-reported symptom improvement between the placebo group and drug groups.

"If the results are promising, we want to study more patients over a longer time. This would allow us to gather more solid information about the therapies and how we can help patients," says Nyberg. "And we are exploring other possible treatments to evaluate in subsequent trials."

J. Richard Landis, Ph.D., at the University of Pennsylvania School of Medicine in Philadelphia is coordinating data collection and analysis.

Notes: A fact sheet on IC is at http://www.niddk.nih.gov/health/urolog/pubs/cystitis/cystitis.htm. A list of centers and doctors is attached and at http://www.niddk.nih.gov/patient/studies.htm.

Interstitial Cystitis Clinical Trials Group

Maryland John Warren, M.D. University of Maryland, Baltimore (410) 706-7560 New York Edward M. Messing, M.D. University of Rochester, Rochester (716) 275-3345 Massachusetts Grannum R. Sant, M.D. Tufts University School of Medicine New England Medical Center, Boston (617) 636-7956 Oklahoma Daniel J. Culkin, M.D. University of Oklahoma, Oklahoma City (405) 271-6900 Michigan Ananias C. Diokno, M.D. William Beaumont Hospital, Royal Oak (248) 551-0387

David Burks, M.D. Henry Ford Hospital, Detroit (313) 916-2075 Pennsylvania Alan J. Wein, M.D. University of Pennsylvania, Philadelphia Marilou Foy, R.N. C.C.R.C. (215) 349-5874

Kristine E. Whitmore, M.D. Graduate Hospital, Philadelphia Marilou Foy, R.N., C.C.R.C. (215) 349-5874