But a day after Keehan spoke, on July 29, the large pharmacy benefit manager Express Scripts made clear it remains worried spending on the drugs could eventually top $100 billion annually, noting that "additional clinical trials are underway for PCSK9 inhibitors that ultimately may expand the target population in 2017, further increasing this potential cost burden."
"Even if physicians adopt this new therapy slower than anticipated, it is clear that PCSK9 inhibitors are on a path to become the costliest therapy class this country has ever seen," wrote Dr. Steve Miller, chief medical officer and senior vice president at Express Scripts, in a blog post.
Miller added that the $14,600 per patient per year announced price of Praluent, the PCSK9 inhibitor made by Sanofi and Regeneron that won Food and Drug Administration approval July 24, "is on the high end of what we were expecting." It's also about 50 times the price of generic statins that many people use to control their cholesterol.
He also wrote that over the next month, during which Amgen's competing drug Repatha is expected to win FDA approval, "we will work hard ... to achieve the best possible for the patients and payers that we represent."
"In the immediate term, we will cover Praulent for those patients for whom the drug is clinically appropriate," Miller wrote.
When the FDA approved Praulent, it did so for use by patients who are already at their "maximally tolerated statin" use who have a genetic condition known as HeFH, or heterozygous familial hypercholesterolemia, "or patients with clinical atherosclerotic cardiovascular disease such as heart attacks or strokes who require additional lowering of LDL cholesterol," the agency said. That would mean that an estimated 8 million to 10 million people would be eligible to use Praluent for its approved use.
Miller's blog noted that although all of those people wouldn't be expected to use Praluent at once, the total annual cost from Praluent "could eventually grow to more than $100 billion each year, if not managed properly." Miller noted that amount represents a potential increase of 30 percent to what the U.S. spent on all prescription medication in 2014.
Regeneron, which has begun selling Praluent, said it expects the actual number of patients using the drug will be smaller than the 8 million to 10 million, since a number of those people will be able to lower their cholesterol by upping their statin dosage beyond current levels, or will be disinclined to inject a drug, or for other reasons.
And the pharmaceutical industry trade group PhRMA has also pushed back over claims that PCSK9s will lead to an explosion in overall drug spending.
"Yet again pharmacy benefit managers are making unfounded claims about spending on medicines that disregard the impact of competition and price negotiation in the marketplace," said Robert Zirkelbach, PhRMA senior vice president.
"It is disingenuous to discuss costs without acknowledging the tremendous value medicines provide to patients and the health-care system," Zirkelbach said. "New cholesterol-lowering treatments have the potential to address a significant unmet medical need for patients unable to control their cholesterol levels with existing treatment options and who face a high risk of developing serious and costly cardiovascular complications, such as heart attack and stroke."