Some physicians have expressed the belief that the drug should help all heart failure victims. Of the nine advisers who voted for approval of BiDil, two said the label should not be race-specific.

A clinical trial of the drug in black Americans was halted early when it became apparent that those using the drug did better than those not using it.

That trial, on just over 1,000 individuals, was launched after the FDA turned away the drug following a study involving all races that showed little improvement -- but also gave hints that blacks might have had some benefit.

The maker, NitroMed of Lexington, Mass., then decided on a trial using blacks only, a population that has more than twice the rate of heart failure as whites.

Heart Is Too Weak to Beat Effectively

In heart failure, the heart is too weak to beat effectively and fluid builds up in the lungs. As many as half of all victims die within five years.

The usual treatment is with drugs called ACE inhibitors, but research has indicated they do not work as well in blacks as in whites.

BiDil is a combination of two drugs: hydralazine, which eases blood pressure, and isosorbate dinitrate, which is used for heart pain. The combination also boosts the amounts of nitric oxide in the blood, a substance that is found in lower levels in blacks and which has several roles in heart health.

In the study of 1,050 blacks, half were given standard heart drugs and BiDil while the others got standard drugs plus an inactive placebo.

After about two years, 6.2 percent of those on BiDil had died, compared with 10.2 percent on those on placebo. Also during that period, 16.4 percent on BiDil were hospitalized for heart failure, compared with 24.4 percent of the rest.

The major side effects of BiDil were headache and dizziness, causing some to drop out of the trial.

Label Should Not Be Race-Specific

While the trial that led to the recommendation for approval was conducted in blacks, some physicians have questioned the earlier study, expressing the belief that the drug should help all heart failure victims.

Of the nine advisers who voted for approval of BiDil, two said the label should not be race-specific.

The FDA will now evaluate the study and recommendation before deciding whether to grant approval for sale of the drug. It is not required to follow the recommendations of its advisory committees, but most often does so.