A drug built to lower a heart-attack risk that Black patients carry more often than white patients did not prevent heart attacks. Pelacarsen, made by Novartis, cut lipoprotein(a), known as Lp(a), by 78% in a trial of 8,323 people, and it made no difference to who had a heart attack, a stroke or died of heart disease. Fewer than 4% of the participants were of African ancestry.
The results were presented Saturday at the American Heart Association’s Scientific Sessions and published in the New England Journal of Medicine. Patients at 797 sites in 42 countries had all survived a cardiovascular event and had high Lp(a). After nearly five years, 503 patients on pelacarsen and 511 on placebo had suffered a major cardiovascular event, about 12% in each group.
“The results were completely neutral across multiple analyses,” lead researcher Dr. Steven Nissen said, according to the American Heart Association’s release. The drug also carried costs: 21% of patients taking it stopped treatment because of adverse reactions, against 7% on placebo, and 19 people on pelacarsen had anaphylaxis, against none on placebo.
Lp(a) is an inherited, cholesterol-like particle that standard cholesterol drugs barely touch, which is why this trial was watched so closely. It is also not evenly distributed. In the Atherosclerosis Risk in Communities study, which followed 9,519 adults for 20 to 25 years, 53.5% of Black participants had elevated Lp(a), against 24% of white participants, according to the analysis published in Circulation in 2023. The researchers estimated that high Lp(a) accounted for 10.7% of heart disease cases among Black participants and 4.7% among white participants. They concluded that drugs lowering it could help narrow racial gaps in heart disease.
That promise has now been tested on a population that was about 78% white. The trial does not show that the drug would fail in Black patients, and it does not show it would work. Nobody can say, because the people most likely to benefit were barely in the room. Medicine has done this before: it builds the evidence on one group and hands the result to everyone.
The failure is also not a reason to stop looking. Nissen said measuring Lp(a) remains important for assessing cardiovascular risk. The trial covered only people who had already had a cardiovascular event, so its results say nothing about preventing a first one, and other Lp(a)-lowering drugs are still being studied.
Those trials are enrolling now. Whether they recruit Black patients in numbers that can answer the question is the thing to watch, and sponsors and the National Institutes of Health should be made to show their enrollment figures before the next results arrive.
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