Clinical trials involving

Amgen's

(AMGN) - Get Report

anemia drug Aranesp reveal promising results in patients with heart failure.

Though the two phase II trials did not show a "statistically significant" benefit with these patients -- that is, results that support a firm conclusion that the drug works -- the data did indicate that the drug may reduce the risk of hospitalization and death in those patients.

"All the arrows were pointing the right direction indicating a symptomatic improvement," Dr. Scott Wasserman, an Amgen director and global development leader for Aranesp, said in a company conference call Monday.

Researchers pooled data on 475 patients with symptomatic heart failure and anemia who were given an injection of either Aranesp or a placebo every two weeks for up to a year. Results of the analyses were presented at the European Society of Cardiology meeting on Monday.

Although the trials were designed to study the drug's safety in heart failure patients and not necessarily its efficacy, the drug's impact on the risk of hospitalization and death, as shown in the pooled trial data, showed a definite positive trend, Wasserman said in an interview. The trials showed that the drug was well-tolerated in heart failure patients and justified further investigation in a larger trial, he added.

"These results are especially encouraging because, currently, there are no approved treatments to address the debilitating effects of anemia associated with symptomatic heart failure," says Dr. Dirk J. van Veldhuisen of the cardiology and thoracic surgery department at the University Medical Center in Groningen, Netherlands. "The final results of the phase II program validate the importance of Amgen's recently launched large-scale Phase III RED-HF Trial or Reduction of Events with Darbepoetin alfa in Heart Failure Trial, which will evaluate the effect of treatment of anemia with Aranesp on morbidity and mortality in patients with symptomatic heart failure."

The phase III trial, which is currently enrolling and aims to sign up 3,400 patients, will be monitored by an independent data-monitoring committee to ensure patient safety throughout the trial, Amgen says. Phase III is the trial stage conducted just before a drug is submitted for Food and Drug Administration marketing approval.

Aranesp is already approved to certain patients with chemotherapy-induced anemia, but companies are required to get supplemental approval to market a drug for a different use.

Amgen shares closed down $1.07, or 1.6%, at $65.75 Monday.