Amgen Inc. (AMGN) said its Aranesp anemia drug had no statistically significant effects on patients with kidney disease, anemia and type-2 diabetes in a Phase III trial, dubbed Treat.

"In contrast to a recent, smaller study of ESAs in a similar patient population, Treat did not show a statistically significant adverse effect on all-cause mortality or cardiovascular morbidity when patients were treated to a hemoglobin target of 13 g/dL. We continue to believe that ESAs have a favorable benefit:risk profile when used according to the approved label."

But the study did show an increase in strokes among patients taking Aranesp.

The primary endpoints were composites of time to all-cause mortality or cardiovascular morbidity - including heart failure, heart attack, stroke, or hospitalization for myocardial ischemia - and of time to all-cause mortality or chronic renal replacement therapy.

The U.S. Food and Drug Administration approved Aranesp in 2001 for the treatment of anemia in patients with chronic renal failure, including those on dialysis. The next year, the agency also approved the drug for the treatment of anemia caused by chemotherapy in patients with nonmyeloid malignancies.

Sales growth of Amgen's anemia drugs Epogen and Aranesp began evaporating in 2007, when studies showed a link to risks of cardiovascular disease, cancer progression and death.

In the second quarter, sales of Aranesp dropped 16% to $693 million but still surpassed the Wall Street consensus estimate of $648 million, according to MDRx Financial. The drop in sales came from label changes in the drug last summer that restricted the drug's use in cancer patients, the company said.

Sales of Epogen, an earlier version of Aranesp, rose 3% to $638 million, also beating expectations of $600 million. The increase was driven by patient growth, as well as a price increase.

Amgen's shares fell 0.2% to $60.45 in after-hours trading. The stock is down about 5% for the past year.

-By Kathy Shwiff, Dow Jones Newswires; 212-416-2357;