Abstract
BACKGROUND
Administration of a single broadly neutralizing human immunodeficiency virus (HIV)–specific antibody to HIV-infected persons leads to the development of antibody-resistant virus in the absence of antiretroviral therapy (ART). It is possible that monotherapy with UB-421, an antibody that blocks the virus-binding site on human CD4+ T cells, could induce sustained virologic suppression without induction of resistance in HIV-infected persons after analytic treatment interruption.
METHODS
We conducted a nonrandomized, open-label, phase 2 clinical study evaluating the safety, pharmacokinetics, and antiviral activity of UB-421 monotherapy in HIV-infected persons undergoing analytic treatment interruption. All the participants had undetectable plasma viremia (< 20 copies of HIV RNA per milliliter) at the screening visit. After discontinuation of ART, participants received eight intravenous infusions of UB-421, at a dose of either 10 mg per kilogram of body weight every week (Cohort 1) or 25 mg per kilogram every 2 weeks(Cohort 2). The primary outcome was the time to viral rebound (≥ 400 copies per milliliter).
RESULTS
A total of 29 participants were enrolled, 14 in Cohort 1 and 15 in Cohort 2. Administration of UB-421 maintained virologic suppression.
CONCLUSIONS
UB-421 maintained virologic suppression(during the 8 to 16 weeks of study) in participants in the absence of ART. One participant discontinued therapy owing to a rash. (Funded by United Biomedical and others; ClinicalTrials.gov number, NCT02369146)
Effect of Anti-CD4 Antibody UB-421 on HIV-1 Rebound after Treatment Interruption (N Engl J Med 2019; 380:1535-1545)