"... Just two quick ones, first, can you give us an update on the back up compounds for telaprevir, and whether or not we might see anything head towards clinic this year. And secondly John, if you could just review the characteristics that you look forward for a go/no-go decision on 702? Thanks, like I said, date is coming Q3."
"Well, I actually can't provide you any specifics on the back up on the follow on program. It's just for let's say it�s a highly competitive field and we have a research program that's ongoing. We have a very good eye on which aspects we need to optimize on in order to have the most competitive program. And we are moving forward. But I can't be any more specific than that. ....."
<< backup compounds to TVR >> is not a correct word to say. He, of course, meant to say he wants to know about the second generation compounds. John understood what Meg meant, and answered that Vertex has a program to generate such compounds which would be competitive against other 2nd generation compounds. In a recent paper written by a French group, they showed that different PIs have different resistance profile, and drew a conclusion that combinations of PIs can overcome resistant variants.
Because HCV infection depends critically on viral NS3/4a protease manipulation of host immune defence, PI, which neutralize protease, is the most powerful defence agaist HCV infection at this time (until potent polymerase inhibitors are developed,which don't appear forthcoming).