The US Food and Drug Administration announced that it is permitting the restricted use of Zelnorm (tegaserod maleate) under a treatment investigational new drug (IND) protocol to treat irritable bowel syndrome with constipation (IBS-C) and chronic idiopathic constipation (CIC) in women younger than 55 who meet specific guidelines.

In some instances, patients with a serious or life-threatening disease or condition who are not enrolled in a clinical trial may be treated with a drug not approved by the FDA. Generally, such use is allowed within guidelines called a treatment IND, when no comparable or satisfactory alternative drug or therapy is available, an US FDA release stated.

In addition to the age and gender restrictions, the IND protocol for Zelnorm limits use of the drug to those with IBS-C or CIC whose physicians decide the drug is medically necessary. Patients must sign consent materials to ensure they are fully informed of the potential risks and benefits of Zelnorm.

On March 30, 2007, the FDA asked Novartis, the manufacturer of Zelnorm, to suspend its US marketing and sales because a safety analysis found a higher chance of heart attack, stroke, and unstable angina (heart/chest pain) in patients treated with Zelnorm compared with treatment with an inactive substance (placebo).

At that time, the FDA indicated that there might be patients for whom the benefits of Zelnorm treatment outweigh the risks and for whom no other treatment options were available. FDA committed to work with Novartis to allow access to Zelnorm for those patients through a special program. That work yielded this IND protocol.

"These patients must meet strict criteria and have no known or pre-existing heart problems and be in critical need of this drug," said Steven Galson, M.D., M.P.H., director of FDA's Center for Drug Evaluation and Research (CDER). "Zelnorm will remain off the market for general use."

Irritable bowel syndrome is a disorder characterized most commonly by cramping, abdominal pain, bloating, constipation, and diarrhea. IBS causes a great deal of discomfort and distress, but it does not permanently harm the intestines and does not lead to disease. For some people, however, IBS can be disabling. They may be unable to work, attend social events, or even travel short distances.

Patients are considered to have chronic constipation if they have fewer than three complete spontaneous bowel movements per week and at least one of the following symptoms for at least 25 per cent of those bowel movements: straining, hard stools, incomplete evacuation.