Two new simplified treatment options for people with HIV – a new one a day pill, and a monthly injection – have moved a step closer to availability.
The pill, named Genvoya, is a combination of four currently licensed antiretrovirals – elvitegravir, cobicistat, emtricitabine, and tenofovir. It has been cleared by both the FDA and the European Medicines Agency after completing four clinical trials at various sites; these involved a total of 3171 adults and found the pill to be as effective as other treatment regimens at reducing viral load.
Developed by Gilead Sciences in an attempt to further simplify the drug regimen of individuals being treated for HIV-1, Genvoya has also been designed to place less stress on the kidneys of patients – a common side effect of antiretroviral medication. This has been achieved by modifying the tenofovir component of the treatment; the form of tenofovir used in the combination – tenofovir alafenamide (TAF) – is more effective than tenofovir at entering cells, and can thus be used at lower doses. According to laboratory analyses carried out during drug trials, Genvoya has indeed shown lower kidney toxicity, although increases in serum lipids (cholesterol and low density lipoprotein) have also been found. Nausea was the most common side effect reported by study participants.
Approaching the issue of treatment simplification from another angle, the second treatment is in the form of a monthly or bi-monthly injection. Under investigation by ViiV Healthcare, their system involves two drugs – the currently licensed rilpivirine (Edurant), and cabotegravir – which is currently unlicensed. A stage IIb clinical trial named LATTE-2 (Long-Acting AntireTroviral Treatment Enabling trial), involving 309 adults, has shown that a single injection every four or eight weeks leads to suppression of HIV equivalent to other available treatments. The most common reported side effect was pain at injection site.
These promising results mean that ViiV can move on to Stage 3 clinical trials – larger studies involving greater numbers of patients, and the final stage before a treatment is cleared for general use. The chief scientific and medical officer of ViiV, John Pottage, hopes this will be completed in 2019, with a positive result allowing the FDA and European Medicines Agency to approve licensing.
Injectable HIV treatment is under development by a number of agencies, although many are still in early developmental stages and involve a variety of different drug combinations and dosing schedules. While at first sight injections may seem to be a more complicated treatment option than oral administration in the form of a pill, the low frequency of dosing (in the case of the ViiV treatment as long as once every two months) can offer substantial benefits to certain, often vulnerable, groups. These include individuals with psychiatric or drug abuse problems, who often have difficulty sticking to the routine of daily treatment.
Simplification of treatment schedules has been an ongoing goal in HIV research ever since the introduction of HAART. Simpler treatment makes it more both likely that individuals will remember to stick to the treatment and ensures maximum efficacy of the drugs given; this is especially important in the case of HIV, which, given the chance, has the ability to rapidly adapt. Above and beyond this, increasing the number of effective treatment schedules and options ensures that treatment reaches a greater number and variety of individuals, whatever their background or personal circumstance.
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