This protocol serves to extend the successful treatment for HIV positive patients beyond the endpoints provided by the Phase 2b TaiMed Biologics-sponsored protocol TMB202 (entitled "A Phase 2b Randomized, Double-Blinded, 48-Week, Multicenter, Dose-Response Study of Ibalizumab Plus an Optimized Background Regimen in Treatment-Experienced Patients Infected with HIV-1 (Amended to 24 Week Study)"), for 24 weeks. Ibalizumab may be administered beyond 24 weeks under this protocol as supply permits and patients continue to demonstrate virologic response.

Ibalizumab is to be administered to HIV-infected patients that have responded (defined as a minimum 0.7 log10 decline in HIV-1 viral load from TMB-202 Baseline) on the TMB-202 protocol. In addition to the investigator-selected Optimized Background Regimen, patient(s) will continue to receive the TMB-202 randomized dose of ibalizumab in open-labeled fashion (800mg IV every two weeks or 2000mg IV every four weeks) as per their original drug assignment for the TMB-202 protocol.

Inclusion Criteria:

• Capable of understanding and have voluntarily signed the ICF
• Have documented HIV-1 infection
• Have successfully completed Protocol TMB202 (Amendment 2)(Week 16)
• Have had at least a 0.7 log10 decline in HIV-1 RNA from baseline at Week 16 and beyond while in TMB202 and are no longer eligible to participate in TMB-202 due to TMB-202 protocol-defined virologic failure
• Have not withdrawn or been discontinued from TMB202 9Amendment 2) for any reason
• Are able and willing to comply with all protocol requirements and procedures
• Are 18 years of age or older
• If sexually active, are willing to use an effective method of contraception during the study and for 30days after the last administration of the study drug.

Exclusion Criteria:

• Any active AIDS-defining illness per Category C except for cutaneous Kaposi's sarcoma and wasting due to HIV
• Any significant disease (other than HIV-1 infection) or clinically significant findings, including psychiatric and behavioral problems, medical history and/or physical examination that, in the investigator's opinion, would preclude the patient from participating in this study
• Any current alcohol or illicit drug use that, in the investigator's opinion, will interfere with the patient's ability to comply with the study schedule and protocol evaluations
• Any previous clinically significant allergy or hypersensitivity to any excipient in the ibalizumab formulation