Express Scripts, the largest pharmacy benefit manager (PBM) in the United States, may change its preferred drug formulary to treat the hepatitis C virus (HCV) from Sovaldi (sofosbuvir), made by Gilead Sciences, to an upcoming AbbVie treatment, Reuters reports.

The PBM will consider making the switch if AbbVie’s new drug turns out to be clinically equivalent to Gilead’s treatment, which was approved by the U.S. Food and Drug Administration (FDA) in December 2013.

Express Scripts representatives are eyeing AbbVie’s new interferon-free combo because it is expected to hit markets at a lower overall cost than Sovaldi, which is currently priced at around $1,000 per pill, or $84,000 for a 12-week course of treatment.

The FDA is expected to make a decision on AbbVie’s “3D” multi-drug regimen in December. The pharmaceutical company has not yet disclosed an exact price for the upcoming treatment, but is boasting cure rates of more than 90 percent in Phase III clinical trials.

Another factor for Express Scripts to consider is what the pricing will be for Harvoni, also made by Gilead. Combining Sovaldi with ledipasvir, the drug is expected to be a favorite. It is unclear how a lower cost "3D" will compete on price against Harvoni.