Nov. 19, 2014 -- Lowering cholesterol in new ways -- potentially to unheard-of levels -- was a big topic of discussion at this week's American Heart Association Scientific Sessions conference in Chicago.
Mark Creager, MD, president-elect of the American Heart Association, says the trial combining Zetia and the statin Zocor had the most impact. "This is the first line of evidence that shows when a non-statin drug is added to a statin drug, it resulted in very effective outcomes,” Creager says.
The study followed more than 18,000 people with known heart disease. It found that those who took the two drugs together had a 13% drop in heart attack risk, and a 21% drop in stroke risk, compared to those who only took the statin.
"These findings... reaffirm that reducing LDL cholesterol prevents cardiovascular disease," says Christopher Cannon, MD, one of the lead investigators in the trial.
Cannon says the side effects were minimal, and comparable to those of taking statins alone.
The second cholesterol trial looked at a new class of cholesterol-lowering drugs. These so-called PCSK9 inhibitors work to boost the liver's natural ability to filter cholesterol out of the blood.
"What's been seen is that they can reduce cholesterol, and the bad cholesterol in particular, by 50% more, and that's on top of statin medications," says Cannon, who was also involved with the second trial. "One can get cholesterol levels down to what we're born with, so never-before-seen low levels."
Doctors have long sought alternatives to statins, because some people simply can’t get cholesterol low enough on those drugs alone, he says. Others can’t tolerate the high doses of statins needed for their conditions, or the side effects.
The PCSK9 inhibitors, which are given by injection once every 2 to 4 weeks, are still in testing, but they show great promise.
"So far, there have been no surprises or any big safety issues," Cannon says.
Although trials aren't yet complete, three drug companies -- Amgen, Pfizer and Sanofi -- are working to get a PCSK9 inhibitor to market.
Cannon expects these drugs will be available within the next year or two.
Another question he and other researchers have looked at is the idea of whether cholesterol can be too low.
"We haven't seen that yet, but it remains a little bit of a question," he says. "These drugs are so powerful you can get the cholesterol down to zero, and that seems like it's probably not a good idea, but we don't know yet."
He says PCSK9 inhibitors can work with or without the help of a typical statin drug, so they might be a good option for people who can't get cholesterol levels low enough on statins, can't tolerate them, or routinely forget to take them.
"Many of us have thought, 'Well, who would want to take an injection when you could take a pill?'" Cannon says. "On the other hand, if you do that every 2 weeks, or sometimes every 4 weeks, maybe that's easier, and you don't have to worry about taking your pills every day."
These findings were presented at a medical conference. They should be considered preliminary as they have not yet undergone the "peer review" process, in which outside experts scrutinize the data prior to publication in a medical journal.