Inclusion Criteria:  Males and females, age ≥18 years  For cohort 1: HIV-1 infected subjects initiated a stable combination antiretroviral therapy (ART) within 6 months of primary HIV infection (PHI), having the document evidence of initial diagnosis of HIV-1 infection and initiation of ART therapy within 6 months of PHI.  For cohort 2: Chronically HIV-1 infected subjects initiated a stable combination antiretroviral therapy (ART) after 6 months of primary HIV infection (PHI), having the document evidence of initial diagnosis of HIV-1 infection and initiation of ART therapy after 6 months of PHI.  Plasma HIV-1 RNA <50 copies/mL for at least 12 months prior to Screening Visit. An exception for a recorded HIV-1 RNA "blip" (e.g., transient HIV-1 RNA >50 copies/mL) can be considered. Plasma HIV-1 RNA <20 copies/mL at Screening Visit. CD4 cell count >500 cells/µL.  Laboratory values at Screening of:  Absolute neutrophil count (ANC) ≥0.75×10∧9/L; Hemoglobin (Hb) ≥105 g/L (male) or ≥95 g/L (female); Platelets ≥75×10∧9/L; Serum alanine transaminase (SGPT/ALT) < 2 x upper limit of normal (ULN) Serum aspartate transaminase (SGOT/AST) < 2 x ULN Bilirubin (total) <2.5 x ULN unless Gilbert's disease is present or subject is receiving atazanavir in the absence of other evidence of significant liver disease Creatinine ≤1.5 x ULN Clinically normal resting 12-lead ECG at Screening Visit or, if abnormal, considered not clinically significant by the Principal Investigator. Both male and female patients and their partners of childbearing potential must agree to use accepted methods of contraception. Females of childbearing potential must have a negative serum pregnancy test at Screening visit and negative urine pregnancy test prior to receiving the first dose of study drug. Subjects who have two or more potential alternative antiretroviral treatment regimens. Willing and able to participate in all aspects of the study, including use of IV medication, completion of evaluations, attendance at scheduled clinic visits, and compliance with all protocol requirements as evidenced by providing written informed consent.  Exclusion Criteria:  Any active infection or malignancy requiring acute therapy. Hepatitis B infection as manifest by the presence of Hepatitis B surface antigen (HBsAg). Hepatitis C infection as manifest by positive anti-HCV antibody and positive HCV RNA assay at the time of screening. Females who are pregnant, lactating, or breastfeeding, or who plan to become pregnant during the study Unexplained fever or clinically significant illness within 1 week prior to the first study dose Any vaccination within 2 weeks prior to the first study dose. Subjects BMI<20 or >27 kg/m∧2 [BMI＝weight/height∧2]. History of Bleeding Disorder or patients on anti-coagulant therapy Participation in an experimental drug trial(s) within 30 days of the Screening Visit Any known allergy or antibodies to the study drug or excipients  Treatment with any of the following:  Radiation or cytotoxic chemotherapy with 30 days prior to the screening visit Receipt of any fusion inhibitor and monoclonal antibody therapy of any kind in the past. Immunosuppressants within 60 days prior to the Screening Visit Immunomodulating agents (e.g., interleukins, interferons), hydroxyurea, or foscarnet within 60 days prior to the screening visit Oral or parenteral corticosteroids within 30 days prior to the Screening Visit. Subjects on chronic steroid therapy > 5 mg/day will be excluded with the following exception: Subjects on inhaled, nasal, or topical steroids will not be excluded Any other clinical condition that, in the Investigator's judgment, would potentially compromise study compliance or the ability to evaluate safety/efficacy.