Men on preventive HIV pill infected, but why?

Scientists are worried over high infection rates among men using the daily HIV prevention pill within a vaccine study group in Mtwapa, Kilifi.

Out of 170 gay men participating in the study, nine have been infected with HIV, despite religiously collecting their pills.

“In this study, we document a substantial overall HIV incidence rate among the participants,” report scientists from the Kenya Medical Research Institute (Kemri).

Published last Month in the journal EClinicalMedicine, the team had assessed participants’ drug uptake and adherence as well as HIV infection rates.

The use of medication for HIV prevention called pre-exposure prophylaxis or PrEP was launched in Kenya in 2017.

The programme targets persons at high risk of HIV infection, including adolescent girls and young women aged 15 to 24 years. Others are discordant couples, drug injectors, and male and female prostitutes.

The project, however, has been characterised by low uptake and high dropout rates. Data from the Ministry of Health shows only 26,098 users so far against a targeted 500,000 by 2022.

The data also suggests most of beginners drop off within three to six months, with young girls being the most affected. Experts say with consistent and correct use; PrEP can virtually eliminate the risk of HIV infection.

But in the current study, led by Elizabeth Wahome of Kemri, the rate of HIV infection among PrEP users is described as significantly high.

Of the nine men who acquired HIV, five had reported having been using PrEP at the time they were infected.

But when blood tests were carried out on the five, only one person had detectable PrEP concentrations, suggesting the others had not been truthful.

“We also found that among participants taking PrEP for at least six months, only one in seven had sufficient PrEP taken to achieve protection against HIV infection,” says the study suggesting poor adherence.

The researchers were, however, surprised that some participants continued to religiously collect their monthly pill refills without using them. “Why some participants were collecting PrEP monthly and not taking it is not clear.”

But Lisa, a peer educator in a similar programme run by the National Aids & STI Control Programme in Nairobi’s Central Business District says such users are motivated by stipends paid for participating in some of the research activities.

Also some unconfirmed reports have indicated that HIV medicines provided freely in public facilities find their way into the private sector.

But Kemri is in the process of closing up this loophole where some people collect the medicines without intending to use them.

In trials already approved by the Pharmacy and Poisons Board, Dr Nelly Mugo of Kemri will be assessing a urine test to tell whether one has been taking the pills before they can get a refill.

A few drops of the patient’s urine, the researchers say is dropped into the test and tells the health provider “yes” or “no” if the patient has been taking PrEP recently. It works like a pregnancy test.

In most of the local studies, side effects, and the burden of taking pills every day are blamed for poor adherence and discontinuation.

An assessment of the five-year Jilinde PrEP project of the Ministry of Health in May reported massive dropout rates mainly due to drug side effects.

Between 2017 and 2019 Jilinde had enrolled 25,542 people on PrEP, but only 1,908 were still n it up three months later. Of the 3,136 eligible girls, only 154 were still in the programme three months later.