ViiV files monthly HIV jab in Europe

ViiV Healthcare has submitted its once-monthly two-drug injectable therapy for HIV to the EMA, setting up possible approval in the EU next year.

The HIV specialist – which is majority owned by GlaxoSmithKline – says the combination of its integrase inhibitor cabotegravir and Johnson & Johnson’s non-nucleoside reverse transcriptase inhibitor Edurant (rilpivirine) could be the first alternative to daily oral doses of antiretroviral therapy (ART) for keeping HIV suppressed.

The marketing application is based on the results of the pivotal FLAIR and ATLAS trials, which showed the monthly injection was as effective as a standard three-drug oral regime at suppressing levels of HIV in previously-treated and treatment-naïve patients. It has already been submitted for approval in the US.

ViiV says patient surveys suggest those who switched to the long-acting injectable regimen preferred it over their prior oral therapy. It also thinks having just 12 doses a year delivered by a healthcare practitioner could lead to improved adherence to ART – and less chance of stimulating drug resistance – than daily oral dosing.

It’s just one of the ways ViiV is trying to wrest market share from Gilead Sciences, its arch-rival in the HIV sector with a market share of more than 50% from its three-drug combination ART products against ViiV’s 22% or so.

ViiV is also trying to build momentum behind two-drug ART combinations given once-daily, arguing that reduces the exposure of people with HIV to drug compounds and might also cut side effects.

Gilead on the other hand says that using two- rather than three-drug combinations could increase the risk of drug resistance, particularly in real-world settings where people may miss a dose.

ViiV recently reported 48-week data from its TANGO trial of two-drug combo Dovato (dolutegravir/lamivudine) which found no evidence of resistance mutations after 48 weeks’ treatment.

With the once-monthly depot GSK could sidestep the resistance issue altogether, although it does introduce other issues. ViiV has just kinked off a new study – called CUSTOMIZE – to try to address what would actually be an increased frequency of clinic visits compared to oral ART.

Currently people on ART typically meet with their doctors once or twice a year, so having to step up that frequency to a monthly visit will involve changes to typical medical practice.

Cabotegravir/rilpivirine could see competition in future from a rival drug from Merck & Co – nucleoside reverse transcriptase translocation inhibitor islatravir (MK-8591) - that the company believes could offer a year of anti-HIV activity from a single implant.

However, rather than positioning it as a treatment for HIV-positive people, Merck is looking at using islatravir for pre-exposure prophylaxis or PrEP – protecting people who are HIV-negative but at a higher risk of contracting the virus, for example if they are in a sexual relationship with an HIV-positive person.

Another company – Taiwan’s United BioPharma – recently reported phase 2 results with an antibody that suppressed HIV for up to four months after patients stopped taking antiretroviral medicines.