FDA advisers endorse heart failure drug for black patients


GAITHERSBURG - A drug specifically intended for use by African-Americans with congestive heart failure received a major boost yesterday when an advisory committee to the U.S. Food and Drug Administration recommended unanimously that the agency approve it.

If the FDA accepts the committee's advice, as it usually does, BiDil would become the first drug approved in the United States for use by a particular racial or ethnic group. FDA action on the application could come next week.

Black medical experts in the audience cheered the committee's vote yesterday. Dr. Charles Curry, president of the International Society on Hypertension in Blacks and former chief of cardiology at Howard University College of Medicine, called BiDil "the most important advance in the care of black people I've seen in my lifetime."

But a long-simmering controversy over the drug continued as well, with one panel member warning against race-based diagnosis and treatment.

Doctors would still be free to prescribe BiDil for other, non-African-American patients, a practice called "off-label" usage. But it's likely that the vast majority of prescriptions will be written for black patients. Studies have found that African-Americans have higher rates of heart failure than other groups and don't respond as well to traditional drug therapy.

Clinical studies of BiDil, which included only seriously ill African-American patients already receiving state-of-the art treatment for their illness, found sharp reductions in mortality and hospitalization when BiDil was added to their treatment, compared with those taking a placebo. Measures of the BiDil patients' quality of life also improved.

The stakes are huge for the drug's Massachusetts-based maker, NitroMed, which holds a patent good until 2020 if the formulation is labeled for use by black patients, but for just two years if approved for the general population.

Depending on which analysts are correct, annual sales of the drug could range from $300 million to more than $800 million. The committee action came too late to boost NitroMed's stock, which closed at $19.51, up 10 cents.

The 9-0 vote, after eight hours of testimony, cheered the company and others in the audience, who saw it as a rare instance in which the American medical system acted to address the particular needs of blacks, who have historically been under-served.

Almost all of the 13 people who spoke during a period of public testimony called for approval of the drug. Some urged that its labeling be broadened to include the general population.

Dr. Lucille Norville-Perez, health director for the NAACP, said that "anything short of approval of the use of BiDil in this population cannot be justified. African-Americans continue to die from heart disease at an alarming rate."

Dianna Wells, an African-American heart failure patient, said that since she signed up to participate in the BiDil trials, she has been able to return to work, climb stairs and sleep without awakening gasping for breath.

"I can't imagine my life without BiDil," she said.

Others, however, worried that the decision would reinforce public confusion about the nature of race, which geneticists and anthropologists are finding has only a tenuous connection to an individual's genetic heritage and likely response to drug therapy.

"I'm not sure what they mean by African-American," said Vivian Ota Wang, of the National Genome Research Institute at the National Institutes of Health and a committee member. "The implication is that it means something biological, when it is in fact a sociological and political construct."

The racial criterion that NitroMed used for including patients in the trials was self-identification as African-American. When Wang, who is Asian, asked whether she would have been included had she identified herself as African-American, the answer was yes.

Identification of a patient's race based on a doctor's perception of skin color, or on self-identification, will lead to ineffective treatment for many, she said. She nevertheless voted for approval, she said, "because there is a benefit. But it's for all people, not just African-Americans."

Of the nine committee members who voted yesterday, two asked specifically that BiDil be labeled for use by African-Americans. Two others recommended that the labeling not be restricted.

Dr. Robert Temple, director of the FDA's Office of Drug Evaluation, said that in their discussions, the committee majority clearly signaled that, because NitroMed's evidence for the effectiveness of the drug was collected from African-American patients, the drug should be labeled for that population.

Nearly 5 million Americans of all races are believed to suffer from heart failure, defined as the progressive inability of the heart to maintain adequate blood circulation through the body and its extremities. The condition leads to weakness, swelling, shortness of breath, enlargement of the liver and premature death.

But the incidence of heart failure among African-Americans is higher than in other groups. An estimated 750,000 blacks - about three in every 100 - have been diagnosed with the disease.

In its clinical study, NitroMed enrolled 1,050 black heart failure patients and found a 43 percent reduction in the relative risk of death for those using BiDil, and a 39 percent cut in the risk of hospitalization, compared with those taking a placebo.

BiDil combines doses of two generic drugs that have been around for decades. Isosorbide dinitrate was approved by the FDA in 1961 for treatment of angina - chest pain caused by inadequate blood supply to the heart. Hydralazine was approved in 1952 to lower high blood pressure.

Most of the deliberation yesterday by the FDA's Cardiovascular and Renal Drugs Advisory Committee focused on the statistical strength of the evidence for the drug's effectiveness.

Committee members were concerned about the trial's novel design and the fact that the company's application for approval was based on a single clinical trial. The standard is usually two.

They also fretted over the wedding of two drugs at a fixed dose in BiDil's formulation, and over the impact on the data from the company's decision to end the trial early when higher mortality rates emerged among patients receiving a placebo.

BiDil and heart failure

Heart failure is a progressive weakening of the heart muscle.

5 million Americans suffer from heart failure, including 750,000 African-Americans.

Middle-age blacks are 2 1/2 times as likely as whites to die from heart failure.

BiDil, made by NitroMed in Lexington, Mass., might help by increasing levels of nitric oxide, which lowers blood pressure.

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