A study of alirocumab showed similar results. Both studies were published last month in the New England Journal of Medicine.
“We know from previous research that evolocumab lowers LDL cholesterol, but these data offer support for their potential to reduce major adverse cardiovascular events in our patients,” said Dr. Marc Sabatine, a senior cardiologist at Brigham and Women's Hospital in Boston and lead investigator in the evolocumab study.
Still, some experts raise questions about the efficacy and safety of the new drugs. Dr. Neil Stone, a lipid expert at Northwestern University and lead author of the 2013 American Heart Association/American College of Cardiology guidelines for treating cholesterol in people at high risk for cardiovascular diseases, called the new research “promising but not definitive.”
“It's not enough just to lower cholesterol. You want to be able to say that (the drugs) reduce the rate of heart attack and stroke,” he said.
Stone noted that previous promising cholesterol-lowering drugs turned out to have safety issues. He cited Pfizer's torcetrapib, which lowered LDL and raised good cholesterol but was found in 2006 to increase mortality.
But the drug companies express confidence in the evidence they submitted to the FDA. Carrie Brown, a spokeswoman for Sanofi/Regeneron, said data from more than 5,000 patients, across 10 Phase 3 double-blind Odyssey trials, are the basis for their global regulatory submissions. “This is one of the largest sets of data ever used to support the initial regulatory filing of an LDL-C lowering therapy,” she said.
Cuyler Mayer, an Amgen spokesman, said the biologics licensing application for evolocumab contains data from approximately 6,800 patients, including more than 4,500 patients with high cholesterol in 10 Phase 3 trials.
Outcome trials are not expected to be completed until 2017. Nevertheless, the FDA has set Prescription Drug User Fee Act deadlines for making its determination in July for alirocumab and August for evolocumab.
Dr. Harlan Krumholz, a cardiologist and a health policy researcher at Yale University, said it's not unusual for the FDA to approve preventive medications, especially to treat high cholesterol, diabetes and hypertension, before complete data on efficacy are in. “People will have to realize that there will be some uncertainty about whether this drug helps people or not, or whether it just makes their lab tests look better,” he said.