- Additional Inclusion Criteria for HIV-infected participants a) participants must have a positive HIV-1 and/or -2 serology test within 6 months of screening, including the day of screening; b) participants must have a Screening CD4+ cell count >200 cells/microliter (mcL); c) in part 1, all participants must be on a stable highly active antiretroviral therapy (HAART) regimen for 4 weeks prior to Screening, in part 2 participants with screening CD4+ cell count <350 cells/mcL must also be on a stable HAART regimen for 4 weeks prior to Screening