The Food and Drug Administration on Tuesday approved the first U.S. drug to treat irritable bowel syndrome with constipation in adult women, a medicine marketed by Takeda Pharmaceutical Co and its developer, Sucampo Pharmaceuticals Inc.
The drug, Amitiza, was approved for women over 18 years old, but not for men, because its effectiveness was not conclusively demonstrated, the FDA said in a statement.
Irritable bowel syndrome is a disorder characterized by cramping, abdominal pain, bloating, constipation, and diarrhea. It affects twice as many women as men, the FDA said.
"For some people IBS can be quite disabling, making it difficult for them to fully participate in everyday activities," said Dr. Julie Beitz of the FDA's Center for Drug Evaluation and Research. "This drug represents an important step in helping to provide medical relief from their symptoms."
The safety and effectiveness of Amitiza was established in two studies involving 1,154 patients diagnosed with IBS-C, the agency said. More than 90 percent of patients in the studies were women.
The studies showed that more patients treated with Amitiza reported moderate or significant relief than those who received a placebo. The safety of long-term treatment was assessed in a study in which all patients were treated with Amitiza for a duration that ranged from 9 months to 13 months, the FDA said.
The drug was found to have some side effects, such as nausea, diarrhea, and abdominal pain, the FDA said.
Amitiza is already approved for the treatment of chronic idiopathic constipation at 24 micrograms twice a day, much higher than the 8 micrograms twice a day recommended for treatment of IBS-C.
The FDA, in its statement, described both Takeda and Sucampo as manufacturers of Amitiza but a spokesman for Sucampo said that while both companies market the drug, Sucampo was the developer.
An FDA spokeswoman could not be reached for comment.