ViiV to begin trials of HIV prevention injection

GlaxoSmithKline’s ViiV Healthcare joint venture is developing an injectable pre-exposure prophylaxis (PrEP) which can prevent permanent HIV infection

According to Reuters, ViiV, a joint venture between GSK, Pfizer and Shionogi, is developing the first injectable PrEP treatment in collaboration with US government agencies and the Bill and Melinda Gates Foundation.

Gilead’s Truvada (tenofovir+emtricitabine) is already approved in this use, but as a pill, has to be taken as directed, and adherence has proved to be an issue for users.

Gilead is already beginning PrEP trials of Descovy, a newer version of the treatment with fewer side-effects – but this will not solve some of the other problems posed by an oral PrEP treatment.

ViiV says that an injectable PrEP treatment will be more acceptable to some patients who would rather not have HIV tablets in the house, because they are concerned about what partners or neighbours would think.

The joint venture is planning to start a four-year trial in the coming weeks based around its experimental drug cabotegravir in gay men in the Americas and Thailand, with a second trial next year assessing the medicine in African women.

This follows two separate phase 3 studies evaluating cabotegravir in combination with Janssen’s rilpivirine, announced earlier this month.

Myron Cohen of the University of North Carolina, who is involved with the PrEP programme, said that although a vaccine is the “holy grail” of HIV research, scientists are also excited by the possibility of using slow-release drug implants to protect against the disease.

Use of Gilead’s Truvada in PrEP has proved to be a thorny issue in England, after the government gave the impression it would fund a national programme based on findings of the PROUD study.

But earlier this year it did a U-turn and said the NHS would only fund small pilot projects, arguing that local authorities are the only bodies that could legally fund disease prevention treatments.

This argument has since been overturned in the Court of Appeal after months of legal battles between HIV campaigners and the government, and NHS England is due to make a fresh decision on whether to fund Truvada PrEP soon.