A late-stage clinical trial of Amgen Inc.’s anemia drug Aransep ended in disappointing results after failing to reduce deaths in heart-failure patients, the company said Wednesday.

The Thousand Oaks biotechnology company recently completed Phase III trials of the drug, testing its ability to boost red blood cell production in anemia patients. The company said no new safety concerns had arisen, but that the trial, begun in 2006, failed to meet expectations by failing to reduce the endpoint time of death.

“The (trial) was designed and powered to evaluate whether the treatment of anemia could improve morbidity and mortality in systolic heart failure patients,” said Michael Severino, senior vice president of Global Development and corporate chief medical officer at Amgen, in a prepared statement.

The drug is currently approved for treatment of anemia due to chronic kidney disease and anemia patients undergoing certain chemotherapies. The company said it will release its full findings at an undisclosed upcoming medical meeting.

The Food and Drug Administration limited labeling of the drug in 2011 following other independent trials. Last month, Amgen pleaded guilty in federal court to marketing Aransep for off-label uses.

Shares of Amgen closed down 76 cents, or less than one percent, to $84.32 on the Nasdaq.