A Dose-Escalation Study of MDX-010 Administered Monthly as Immunotherapy in Subjects Infected With Human Immunodeficiency Virus (HIV)

Inclusion Criteria:

- Detectable HIV viremia (HIV-1 RNA level between 1,000 and 100,000 copies/mL)

- CD4 count greater than or equal to 100 cells/mm3

- Current antiretroviral therapy regimen following at least 2 previous changes for
documented virologic failure

- Documented resistance tests demonstrating the presence of at least 1 mutation to each
major therapeutic class of antiretroviral therapy

- No significant organ compromise

Exclusion Criteria:

- Initiation of any new medications that might reasonably affect the immune response or
viral load within 4 weeks prior to screening

- Tetanus booster immunization within 2 months of screening, or a history of anaphylaxis
or severe local reaction to the tetanus vaccine

- History of autoimmune disease at risk for recurrence

- Current malignancy, except Stage A or B cervical carcinoma or basal cell carcinoma

- Chronic viral hepatitis, due to Hepatitis B or Hepatitis C undergoing current
treatment or Hepatitis B DNA greater than 25 pg/cc or Hepatitis C RNA greater than
20,000 IU/cc

- Currently undergoing treatment or prophylaxis for tuberculosis infection

- Chronic active infectious disease (other than HIV)