The prescription product (Vascepa), consisting of a “highly purified” form of the omega-3 acid eicosapentaenoic acid (EPA), was heralded in 2018 (N Engl J Med. 2019;380:11-22) as ushering in “the dawn of a new era” in cardiovascular disease (CVD) prevention that “should definitely change practice going forward,” according to REDUCE-IT’s lead author Deepak L. Bhatt, MD, formerly of Brigham and Women’s Hospital in Boston and now director of the Mount Sinai Heart Center in New York.
However, skeptics questioned why the results differed from most previous trials of fish oil that showed no benefit. Was it caused by the high dose of EPA: 4 g/daily versus 1 g daily in earlier trials with fish oil capsules? Was it the different formulation of purified EPA versus more common combinations of EPA plus docosahexaenoic acid (DHA)? Or, as suggested by Steven Nissen, MD, chief academic officer of Cleveland Clinic’s Heart and Vascular Institute and others, was it caused by the negative effects of the mineral oil placebo, given the significant increases in LDL cholesterol and high-sensitivity C-reactive protein (hsCRP) seen in the control group?
‘Not all omega-3s created equal’
Dr. Bhatt recently said in an interview: “I think there’s confusion in the field. It’s a challenge when just one drug in a class looks good and everything else in that class looks bad. That in itself can breed some skepticism. Also, not everyone always embraces advances. Some people have other reasons to impugn datasets; for example, it could be because they are running competing trials with competing drugs.”
REDUCE-IT enrolled more than 8,000 patients at high CV risk despite statin treatment, and randomly assigned them to 2 g of EPA twice daily or the mineral oil placebo. Although the results showed a 25% reduction in the rate of CV events in the EPA group, there was also an increased risk of atrial fibrillation among those taking EPA after a median of 4.9 years follow-up.
Dr. Bhatt noted that Amarin, which manufactures Vascepa, is essentially a one-drug company, and its stock price is dependent on the product. When the trial results were released, he said, “there were people in the investor world that wanted the stock price to go up or wanted it to go down, and they were alternately hyping or disparaging the data in both cases, sometimes inappropriately and excessively, which created noise around the science.”
The fact is, he said, “not all omega-3 fatty acids are created equal. There are differences between supplements and prescription medicines, and within the prescription medicines, differences between pure EPA and the mixtures of EPA and DHA.”
Dr. Bhatt added that other trials also showed positive results. He pointed to the JELIS trial, published in 2007, which showed a 19% reduction in major adverse CV events with a 1.8-g daily EPA dose.
More recently, RESPECT-EPA was presented at the 2022 annual meeting of the American Heart Association. That study had methodological issues and was underpowered, but it did suggest a possible benefit of EPA in reducing CV events in patients with chronic coronary artery disease who were taking statins. “Looking at the totality of evidence, I think it’s quite clear there’s CV benefit,” Dr. Bhatt said.