Gilead Sciences may finally be forced to offer a lower price for its $94,500 hepatitis C drug.

The biotechnology company could have no choice but to negotiate its own discounts with CVS Health Corp say analysts, after rival drugmaker AbbVie announced a deal to block Gilead's pill Harvoni from a list of medicines covered by Express Scripts Holding.

Express Scripts manages pharmacy benefits for about 85 million people in the US, while CVS had about 26 per cent of the pharmacy benefits market in the US last year, behind Express Scripts, according to the US Department of Labor.

"Does Gilead really want to be blocked from half of the US population?" John Kreger, an analyst at William Blair and Co, said. "They would be the most motivated to cut a deal with CVS."

AbbVie’s deal with Express Scripts flips the power balance to favour insurers who now can pit drugmaker against drugmaker to force price cuts. – (Bloomberg)