This study will enroll participants from the RV 217 study who are diagnosed with early acute HIV infection. Participants will be randomly assigned to one of three groups: Group 1 will begin ART and receive a single infusion of placebo at Day 0. Group 2 will begin ART and receive a single infusion of VRC01 at Day 0. Group 3 will receive a single infusion of VRC01 on Day 0 and begin ART on Day 7. ART will vary by country and will consist of country guideline-recommended first line combination therapy: either efavirenz 600 mg/emtricitabine 200 mg/tenofovir disoproxil fumarate 300 mg or efavirenz 600 mg/lamivudine 300 mg/tenofovir disoproxil fumarate 300 mg. This initial ART regimen may be adjusted or switched to an alternate regimen as clinically indicated for regimen intolerance or failure.