MGD014 in HIV-Infected Individuals on Suppressive Antiretroviral Therapy

Eligible participants will be maintained on ART and receive either one infusion (Part 1) or
multiple infusions of MGD014 (Part 2). Part 1 is a single ascending dose study with a 1+3
design for the first 2 dose cohorts, and a 3+3 design with staggered accrual for the 6 higher
dose cohorts, with an aim of determining the safety, pharmacokinetics (PK), and
pharmacodynamics (PD) of ascending doses up to either the Optimal Biologic Dose (OBD) or the
maximum administered dose (MAD).

Part 2 is a multi-dose expansion cohort with MGD014 administered at the OBD, as determined in
Part 1. In Part 2, additional assessments on the effects of MGD014 on HIV latent infection
parameters will be evaluated.

Inclusion Criteria:

- Ability and willingness of participant to provide written informed consent.

- Karnofsky performance status > 70.

- HIV-1 infection, documented by any FDA-approved rapid HIV test or HIV enzyme or
chemiluminescence immunoassay (E/CIA) test kit at any time prior to study entry and
confirmed by a licensed Western blot or a second antibody test by a method other than
the initial rapid HIV and/or E/CIA, or by HIV-1 antigen, plasma HIV-1 RNA viral load.

- On a potent, stable, continuous ART regimen for ≥ 6 months prior to Screening.

- Plasma HIV-1 RNA < 50 copies/mL at two time points in the previous 12 months prior to
screening (one time point can be screening) and never ≥ 50 copies/mL on 2 consecutive
time points in the last 24 months.

- Adequate organ function based on acceptable laboratory parameters.

Exclusion Criteria:

- Women of childbearing potential defined as any female who has experienced menarche and
who has not undergone successful surgical sterilization or menopause.

- Weight > 115 kg or < 53 kg.

- History or other evidence of severe illness, immunodeficiency other than HIV, or any
other condition that would make the potential participant unsuitable for study.

- History or other evidence of any condition or process for which signs or symptoms
could be confused with reactions to MGD014.

- History of any HIV immunotherapy or HIV vaccine except for MGD014 within 12 months
prior to screening.

- History of clinically significant cardiovascular disease, severe allergic reactions,
malignancy within 5 years, seizure disorder within 2 years, organ/tissue transplant,
autoimmune disease, unstable asthma, bleeding disorder.

- Active, untreated syphilis.

- Use of blood products, cytokine therapy, growth-stimulating factors, cytotoxic
chemotherapy or investigational therapy within 90 days.

- Current use of the antivirals maraviroc and/or enfuvirtide.

- Any vaccination within 30 days of screening.