ViiV Healthcare, the global specialist HIV company majority owned by GlaxoSmithKline plc (GSK), with Pfizer Inc and Shionogi Limited as shareholders, announced the European Marketing Authorisation of Rukobia (fostemsavir) 600mg extended-release tablets, for use in combination with other antiretroviral (ARV) therapies for the treatment of adults with multidrug-resistant HIV-1 infection, for whom it is otherwise not possible to construct a suppressive anti-viral regimen.
Fostemsavir is a first-in-class HIV attachment inhibitor; it works by targeting the first step of the HIV lifecycle and shows no cross-resistance to other currently licensed antiretroviral classes, offering a new option to this group of people who are multidrug-resistant and at risk of disease progression and death.
Fostemsavir, under the brand name Rukobia, was licensed by the US Food and Drug Administration on 2 July 2020, and further regulatory applications have been submitted worldwide.
Rukobia (fostemsavir) is a first-in-class HIV-1 attachment inhibitor. After oral administration, fostemsavir is converted to temsavir, which is then absorbed and exerts antiviral activity by attaching directly to the glycoprotein 120 (gp120) subunit on the surface of the virus, thereby blocking HIV from attaching to host immune system CD4+ T-cells and preventing the virus from infecting those cells and multiplying. As fostemsavir is the first ARV therapy to target this step of the viral cycle, there is no demonstrated resistance to other classes of ARVs, which may help patients whose HIV infection has become resistant to most other medicines.
Clinical basis of approval
The Marketing Authorisation Application (MAA) for fostemsavir is supported by data from the pivotal phase III BRIGHTE study, which evaluated the safety and efficacy of fostemsavir in combination with an optimised background therapy (OBT) in heavily treatment experienced (HTE) adults living with multidrug-resistant HIV, many of whom had advanced HIV disease at study entry. In the randomised cohort, 60% (n=163/272) of individuals who received fostemsavir in addition to an investigator-selected OBT achieved undetectable HIV viral load and clinically significant improvements to CD4+ T-cell count through week 96.
The BRIGHTE trial is an international, phase III, partially-randomised, double-blind, placebo-controlled study conducted in 371 heavily-treatment experienced (HTE) adults living with HIV-1 infection with multidrug resistance. All trial participants were required to have a viral load =400 copies/mL and =2 classes of ARV medications remaining at baseline due to resistance, intolerability, contraindication, or other safety considerations.