Biotech Values

[DewDiligence]

Re: IDIX’s two protease HCV inhibitors

Based on yesterday’s Morgan Stanley webcast, IDX316 has been designated the lead PI and IDX136 is the backup. Good call by GG and bad call by me.

What it means: IDIX is positioning IDX316 as a component of an all-oral HCV cocktail, rather than a sole addend to the current interferon + ribavirin standard of care. If IDIX had been interested in developing a PI as an addend to the current SoC, I think IDX136’s higher barrier to resistance would have trumped IDX316’s greater potency (i.e. lower dose) and longer half-life. (The half-life would have been relatively unimportant because ribavirin is a BID drug).

IDIX has evidently been impressed by the progress to date of Roche’s INFORM-1 study, and they intend to mimic Roche’s progress by employing a combination of IDX184 and IDX316. In such a nuke+PI cocktail, IDX184 (the nuke) can mitigate the relatively rapid onset of resistance to IDX316 (compared to IDX136), which renders the PI’s barrier to resistance somewhat less consequential than it would be in a PI+SoC cocktail.