The FDA has declined to approve Zealand Pharma's bowel disease drug and sought an additional trial to confirm the drug's safety and efficacy, the company said.

The health regulator concluded in its so-called complete response letter that Zealand's application did not provide enough evidence to prove the effectiveness and safety of the proposed dose of the drug, glepaglutide, the company said.

The company was studying the drug to treat adults suffering from short bowel syndrome with intestinal failure who are dependent on parenteral support.

Parenteral support is a medical procedure where nutrition and fluids are delivered to patients through a vein, bypassing the digestive system.

Short bowel syndrome is a rare, chronic condition that affects the functioning of the small intestine, causing malabsorption of nutrients.

It affects about 7,500 adult patients in the United States, according to company estimates.

Zealand will continue discussions with the FDA to align on the steps needed to secure regulatory approval in the U.S.