Study to Evaluate the Safety and Efficacy of Teropavimab and Zinlirvimab in Combination With Lenacapavir in Virologically Suppressed Adults With HIV-1 Infection

A Phase 1b Randomized, Blinded, Proof-of-Concept Study to Evaluate the Safety and Efficacy of Broadly Neutralizing Antibodies (bNAbs) GS-5423 and GS-2872 in Combination With Capsid Inhibitor Lenacapavir (GS-6207) in Virologically Suppressed Adults With HIV-1 Infection

The primary objective of this study is to evaluate the safety and tolerability of a combination of the broadly neutralizing antibodies (bNAbs) teropavimab (formerly GS-5423) and zinlirvimab (formerly GS-2872) in combination with the HIV capsid inhibitor lenacapavir (LEN).

Key Inclusion Criteria:

• On first-line antiretroviral therapy (ART) for ≥ 2 years prior to screening. A change in ART regimen ≥ 28 days prior to screening for reasons other than virologic failure (VF) (eg, tolerability, simplification, drug-drug interaction profile) is allowed

• No documented historical resistance to the current ART regimen

• Plasma HIV-1 RNA < 50 copies/mL at screening

• Documented plasma HIV-1 RNA < 50 copies/mL for ≥ 18 months preceding the screening visit (or undetectable HIV-1 RNA level according to the local assay being used if the limit of detection is ≥ 50 copies/mL). Unconfirmed virologic elevations of ≥ 50 copies/mL (transient detectable viremia, or "blip") prior to screening are acceptable.

• Proviral phenotypic sensitivity to both teropavimab and zinlirvimab at screening by the PhenoSense mAb Assay (Monogram Biosciences) for inclusion in the Primary Cohort; sensitivity at screening by the PhenoSense mAb Assay (Monogram Biosciences) to 1 mAb, either teropavimab or zinlirvimab, within 18 months prior to enrollment for inclusion in the optional Pilot Cohort

  -- In both cohorts, teropavimab sensitivity is defined as 90% inhibitory concentration (IC90) ≤ 2 μg/mL; zinlirvimab sensitivity is defined as IC90 ≤ 2 μg/mL;

• Cluster determinant 4+ (CD4+) count nadir ≥ 350 cells/μL

• Screening CD4+ count ≥ 500 cells/μL

• Availability of a fully active alternative ART regimen, in the opinion of the investigator, in the event of discontinuation of the current ART regimen with development of resistance

Key Exclusion Criteria:

• Comorbid condition requiring ongoing immunosuppression
• Evidence of current hepatitis B virus (HBV) infection
• Evidence of current hepatitis C virus (HCV) infection (prior infection cleared spontaneously or with treatment is acceptable)
• History of opportunistic infection or illness indicative of Stage 3 HIV disease

Note: Other protocol defined Inclusion/Exclusion criteria may apply.