|The analysis was
done using two definitions of treatment failure
protocol-defined treatment failure (PDTF) definition and
|2) subjects with
PDTF plus subjects with >400 copies/mL at Week 24
|Regardless of the
definition of treatment failure, more subjects (~50-60%) failed with CXCR4-
or dual/mixed-tropic virus in the MVC arms, whereas >80% of the subjects
in the placebo arm failed with CCR5-tropic virus.
|A high percentage
of treatment failure on MVC appears to be driven by tropism change from
CCR5-tropic to CXCR4- or dual/mixed-tropic virus.
|This supports the
mechanism of action of MVC and suggests emergence of CXCR4-tropic virus is a
prominent reason for failure on MVC.