Association between specific enfuvirtide resistance mutations and CD4 cell response during enfuvirtide-based therapy.

Analysis of CD4 cell responses during 48 weeks of enfuvirtide therapy after virological failure (analysis of covariance) demonstrated significant associations between V38 mutations (n = 58 subjects) and continued CD4 cell increases and between Q40 mutations (n=8) and loss of CD4 cell benefit (+34 versus -95 cells/μl, P<0.001). Subjects with N43 (n=20) or other mutations (n=48) had intermediate CD4 cell responses. These data suggest that key enfuvirtide resistance mutations may be associated with reduced viral pathogenicity in vivo.