What does disappointing results of Gilead’s oral Hep C drug mean for early development in direct-acting antivirals?

GS-7977 was the major asset behind Gilead's $10.8billion acquisition of Pharmasset last year and was at the forefront of big pharma's bet in this field. The megablockbuster prospect of a next-gen oral therapy to quell the hep C virus without the use of interferons (which have well-described side-effects – fatigue, influzena-like symptoms, hematologic abnormalities and neuropsychiatric symptoms) is something that …