# Combined Use of Ibalizumab and Lenacapavir for the Treatment of Multidrug-resistant HIV-1: A Case Series

## TL;DR

A combination of injectable drugs helps people with drug-resistant HIV lower their virus levels and improve immune health.

## Contribution

This study provides real-world evidence on the effectiveness of combining ibalizumab and lenacapavir for multidrug-resistant HIV.

## Key findings

- Combined IBA + LEN treatment reduced viral load by a median of −2710 copies/mL in 12–24 weeks.
- CD4+ counts increased by a median of 67.5 cells/mm³ within 4–44 weeks of treatment.
- The treatment was well tolerated, with few intolerances requiring regimen changes.

## Abstract

Some individuals with human immunodeficiency virus (HIV-1) have acquired multidrug-resistant (MDR) strains of HIV and/or are nonadherent to antiretroviral (ARV) medication. Injectable ARVs can provide salvage therapy for those with limited therapeutic options and may be preferred by some people with HIV (PWH). Real-world evidence may contribute to a more comprehensive understanding of the barriers to adherence and the utility of injectable ARVs in PWH. Currently, there is a lack of data on combined use of injectable ibalizumab (IBA) and lenacapavir (LEN) with optimized background regimen (OBR).

A retrospective observational study examined medical charts from people with MDR HIV across 8 facilities in the United States. All PWH used a combination of both IBA + LEN ± OBR for at least 6 months. Viral loads and CD4+ counts were collected.

A total of 21 PWH were included. Four-class resistance at baseline was reported in 38.1% of PWH. Within 12 to 24 weeks of combined IBA + LEN treatment, a median reduction of −2710 copies/mL HIV RNA was observed. Median increase to CD4+ count was 67.5 cells/mm3 within 4 to 44 weeks of treatment initiation. Few intolerances required changes to treatment. Therapy with IBA + LEN continued for an average of 30 months and 20 months, respectively.

In this small group of individuals with MDR HIV who were heavily treatment-experienced and/or faced adherence challenges, the use of IBA + LEN ± OBR was well tolerated and led to clinically significant reductions in viral loads and improvements in CD4+ counts.

A group of 21 individuals living with multidrug-resistant HIV and/or adherence challenges received injectable ibalizumab and lenacapavir plus optimized background regimen for at least 6 months. People with HIV experienced clinically significant reductions in viral load and increases in CD4+ count after combined treatment.