Romidepsin Plus 3BNC117 Phase 2a Study

Inclusion Criteria: * Adults age 18-65 years with documented HIV-1 infection * CD4+ T-cell count \>500 cells/mm3 at screening * On ART for a minimum of 24 months and HIV-1 RNA plasma level of \< 50 copies/ml by standard assays for at least 18 months (a single viral load measurement \> 50 but \< 500 copies/ml during this time period is allowable). * Individuals on protease inhibitor or NNRTI-based regimens, or regimens containing cobicistat must be willing to switch to an integrase-inhibitor-based regimen (raltegravir or dolutegravir) prior to enrollment. Exclusion Criteria: * Use of systemic corticosteroids, immunosuppressive anti-cancer, or other medications considered significant by the investigators within the last 6 months * Pregnancy as determined by a positive urine or serum beta-hCG. * Participant unwilling to use two reliable contraception methods (i.e. condom with spermicide, diaphragm with spermicide, progestin-only containing intrauterine device (IUD) (eg, Mirena, Implanon, Nuva Ring), non-estrogen containing formulations of hormonal birth control drugs with condom) for the study duration. * Currently breast-feeding. * History of resistance to 2 or more classes of antiretroviral medications * Any medical, psychiatric, social, or occupational condition that, as judged by the investigators, would interfere with the evaluation of study objectives (such as severe alcohol or drug abuse, dementia). * Acute or chronic hepatitis B or C infection as indicated by the presence of Hepatitis B surface antigen (HBsAg) or hepatitis C virus RNA (HCV-RNA) in blood. * A history of AIDS-defining illness within 3 years prior to enrollment. * History of B-cell lymphoma, including CNS lymphoma * CD4 nadir \< 200 cells/mm3 * History of significant coronary artery disease, myocardial infarction, percutaneous coronary intervention with placement of cardiac stents, or family history of sudden death at age \< 50 years. * ECG at screening that shows QTc \>450 msec when calculated using the Fridericia formula from either lead V3 or V4, pathological Q-waves (Q-wave \> 40 msec or depth \> 0.4-0.5 mV), evidence of a ventricular pre-excitation syndromes, complete or incomplete LBBB or RBBB, second or third degree heart block, QRS duration \> 120 msec, or bradycardia defined by sinus rate \< 50 bps * Use of QT-prolonging medication, renal or hepatic disease, structural heart disease or left ventricular dysfunction * Any symptomatic or asymptomatic arrhythmia excluding sinus arrhythmia and bradycardia ≥ 50 bps. * Laboratory abnormalities in the parameters listed below: 1. Absolute neutrophil count ≤ 1,000 cells/μl 2. Hemoglobin \< 11 gm/dL 3. Platelet count \< 125,000 cells/μl 4. Alanine Aminotransferase (ALT) ≥ 1.25 x ULN 5. Aspartate Aminotransferase (AST) ≥ 1.25 x ULN 6. Total bilirubin \> 1.0 ULN 7. Creatinine \> 1.0 ULN * Any vaccination within 14 days prior to 3BNC117 administration * Receipt of any therapeutic HIV vaccine in the past * Receipt of any monoclonal antibody or HDAC inhibitor of any kind in the past. * Participation in another clinical study of an investigational product currently or within past 12 weeks, or expected participation during this study.