Biotech Values

[genisi]

Resistance to telaprevir (from PROVE-2 data)

The preexisting dominant strain in patient's quasispecies was the WT but 2 variants were also present at baseline (in a very small percentage) and perhaps more that were not detected. After a short time of selection stress (telaprevir) highly resistant variants were selected and were seen while viral breakthrough. But there's a price to be paid even for a virus and so highly resistant variants typically are associated with a significantly impaired replicative fitness. Unless they do not compensate by additional mutation/s that restore replicative replication efficiency, then after termination of antiviral therapy they no longer have any advantage and are replaced by lower resistant variants and WT. So I don't think that relapse requires that the virus become at least low level resistant.