At a time when the rising cost of medicines is causing consternation, an exclusive deal between Express Scripts Holding Co. , the nation’s largest pharmacy-benefits manager, and AbbVie Inc., a big drug maker, over a new hepatitis C treatment is generating concern about the implications for patient choice.

The deal came after the benefits manager spent a year railing about the prices charged by Gilead Sciences Inc., which until now has had a lock on the market. Fresh off FDA approval for its drug, AbbVie last month offered Express Scripts an undisclosed discount off its $84,000 list price. The newest Gilead drug, called Harvoni, costs between $63,000 and $94,500, depending upon the regimen.

The benefits manager argues that patients who were previously shut out of treatment now have an option. In response to Gilead pricing, some public and private payers had approved treatment only for the sickest patients. Express Scripts, meanwhile, is making the AbbVie medication available to patients with the most common form of the virus, which amounts to some 70 percent of those infected in the U.S.

There are, however, some crucial distinctions. Although both treatments offer cure rates exceeding 90 percent, the newest Gilead medicine requires patients to take just one pill a day. The AbbVie regimen, known as Viekira Pak, involves a few pills, and about 60 percent of the patients covered by Express Scripts will also need to take another drug called ribavirin, which can be difficult to tolerate. This may lead to adherence issues, as well.

Consequently, some say the deal raises troubling questions about access to the best available care, because patients whose pharmacy benefit is managed by Express Scripts will be directed toward a treatment that a physician may determine is not as desirable.

“Payers exercising cost control is certainly not new, but the burden should be on the payer to justify any deviation from optimal care,” says Art Caplan, who heads bioethics in the Division of Medical Ethics at the NYU Langone Medical Center. “You should lead with medical considerations. In this case, the monetary tail is wagging the medical dog.”

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