Last month, Express Scripts , the nation’s biggest pharmacy benefits manager, and AbbVie reached an exclusive deal that ushered in a price war for hepatitis C treatments. The drug maker offered an undisclosed discount in hopes of breaking the lock that Gilead Sciences has on the burgeoning market. The PBM, which has railed against Gilead pricing, agreed to offer the AbbVie treatment to patients with the most common form of the virus, a population that constitutes some 70% of those infected in the U.S. The AbbVie regimen, however, can be more cumbersome and some physicians worry about patient compliance. We spoke with Steve Miller, the chief medical officer at Express Scripts, about the move. This is an excerpt.

Pharmalot: Let’s talk about this deal.

Miller: We’ve been very consistent over the past year saying the price of hepatitis C products was too high and we had publicly stated a couple of goals. One, we want the price to be low enough to treat everyone. The price was so high that payers had to prioritize patients. They were willing to pay for the sickest patients first in terms of severity. For those who were at an earlier stage, there wasn’t enough money to go around.

Second, the thing we made a lot of comments about is the disparity between Western wealthy countries and America. America has been shouldering the burden of world defense for years, but we cannot be asked to shoulder the burden of pharmaceutical products. This has to be shared more similarly.

We’ve wanted the price to look more similar across western countries. The (AbbVie) discount was large enough so that we narrowed the gap between other Western countries and America. The price is sufficiently low that we can go to our clients and say that they can treat every patient with hepatitis C.