Unexpected dramatic increase in CD4(+) cell count in a patient with AIDS after enfuvirtide treatment despite persistent viremia and resistance mutations

An unexpected dramatic immune recovery was observed in a patient with full-blown AIDS receiving enfuvirtide-based antiretroviral therapy after multiple treatment failures. A complex interplay of viral and host factors, including the control of X4 viruses and proviral burden, may favor immune restoration with HIV neutralizing activity, despite persistent viremia.