ACC.13: Heart-pounding late-breakers

What a wild ride it has been, and most of us have not even packed our bags yet. I am talking about the late-breaking clinical trials program at the American College of Cardiology scientific sessions in San Francisco, which will kick off March 9.

First came the publication of results from HPS2-THRIVE in the European Heart Journal. HPS2-THRIVE (Heart Protection Study 2—Treatment of HDL to Reduce the Incidence of Vascular Events) was designed to assess whether extended release niacin and laropiprant in addition to statins lowered  low-density lipoprotein cholesterol in patients who are at high risk of major vascular events. The authors reported that one-quarter of patients who received the niacin/laropiprant combination discontinued treatment, primarily due to adverse reactions. The niacin/laropiprant group had a four-fold higher risk of myopathy, and the risk was 10 times higher for patients in China compared with Europe.

The negative findings were not a surprise. Trial sponsor Merck revealed last December that HPS2-THRIVE had missed its primary endpoint. The timing of the publication—just weeks before a scheduled March 9 late-breaker presentation of the trial—had the potential to dampen interest, though. But the breadth and depth of data from the trial offers opportunities to explore patient subset, which may lead to new insights.

The second surprise appeared in the form of a press release posted March 4 by Boston Scientific, sponsor of the PREVAIL trial, which is a randomized controlled study comparing the Watchman left atrial appendage closure device to long-term warfarin therapy in patients with atrial fibrillation who are at risk for stroke. Final results of PREVAIL is the opening act for the late breakers. Given the often lamented drawbacks of warfarin, patients and physicians likely welcome options that prove safe and efficacious.

In its release, Boston Scientific announced that only the acute procedural safety results would be presented. Two days later, the company switch course and reported that the presentation would include all three co-primary endpoints: the acute occurrence of death, ischemic stroke, system embolism and procedure device-related complications that require major cardiovascular or endovascular intervention; a comparison of the composite of stroke, systemic embolism and cardiovascular and unexplained death at 18 months follow-up; and a comparison of ischemic stroke or systemic embolism between seven days and 18 months follow-up.

Given the keen need for alternative therapies to warfarin, PREVAIL likely already was on many ACC.13 attendees’ “must see” list. After the seesaw by Boston Scientific, I suspect interest will be even more piqued. Mine sure is.

Stay tuned for daily coverage by Cardiovascular Business of the late-breakers as well as other sessions at ACC.13.

Candace Stuart

Cardiovascular Business, editor