Adolor Corp. and GlaxoSmithKline P.L.C. won a four-year struggle yesterday to sell the first U.S. treatment for constipation after intestinal surgery.

The Food and Drug Administration approved a seven-day regimen of the medicine, Entereg, for hospital patients with a condition known as postoperative ileus, the companies said yesterday in a statement. Entereg, Adolor's first drug, was submitted by the Exton, Pa., company for FDA approval in June 2004.

FDA delayed approving Entereg several times for more test data and concerns about side effects from long-term use. A panel of outside advisers to the agency voted, 9-6, in January that the drug's benefits exceeded risks, with close monitoring of patients and prescribing restrictions. Adolor agreed to develop a program that makes the drug available only to registered hospitals.

"Entereg is the first and only product that has demonstrated the ability to address this serious condition, which has negative consequences for patients, and imposes considerable expense on the health-care system," said Michael Dougherty, Adolor's chief executive officer and president, in the statement.

Entereg may have sales of $155 million by 2012, said David Webber, a Broadpoint Capital Inc. analyst, in a Jan. 22 note to clients.

Adolor rose nearly 12 percent to $6.00 in trading after the Nasdaq Stock Market closed. Shares rose 14 cents, or 2.68 percent, to $5.37 in regular trading.

Glaxo, Europe's biggest drugmaker, has a U.S. headquarters in Philadelphia.