Pharmacist Medication Insights: Ibalizumab (Trogarzo) for HIV

In March 2018, the FDA approved ibalizumab-uiyk (Trogarzo, Theratechnologies), an injectable CD4-directed post-attachment HIV-1 inhibitor, indicated for the treatment of HIV type 1 infection in heavily treatment-experienced adults with multidrug resistant HIV-1 infection failing their current antiretroviral regimen.

With its approval, ibalizumab-uiyk became the first monoclonal antibody to treat HIV. It was also the first HIV therapy with a new mechanism of action to be approved in 10 years.

Ibalizumab-uiyk is a CD4-directed post-attachment HIV-1 inhibitor. It works by blocking HIV-1 from infecting CD4+ T cells by binding to domain 2 of CD4 and interfering with post-attachment steps required for the entry of HIV-1 virus particles into host cells and preventing the viral transmission that occurs via cell-cell fusion.

Notably, the medication binds opposite to the site in domain 1 that is required for CD4 binding of the MHC class II molecules and therefore does not interfere with CD4-mediated immune functions.

Ibalizumab-uiyk is supplied as a single-dose, colorless to slightly yellow solution, 2 mL vial containing 150 mg/mL of medication. Each vial delivers approximately 1.33 mL containing 200 mg of ibalizumab-uiyk. It is commercially available in a carton containing two single-dose vials.