Posted 11 January 2018
HIV (human immunodeficiency virus) is no longer the death
sentence it once was, thanks to the development of numerous tests and
treatments over the years. However, the cocktail of drugs that those diagnosed
with HIV must take daily, just to keep the virus at a low enough level to
maintain a functional immune system, could be considered a life sentence.
Understandably, a way to reduce this frequency of dosing is greatly desired –
and recent research shows that in the future it may become reality. (1)
HIV is primarily a sexually transmitted infection, but it
may also be passed from one person to another via sharing needles or sex toys,
accidentally pricking oneself with a contaminated needle or via blood
transfusion. It can also be passed to a baby during birth or breastfeeding if
the mother is infected. People at greatest risk include homosexual men,
heterosexual black African people of any gender, and anyone who shares needles
or syringes with others. (2, 3)
Once HIV has found its way into the body, it hijacks
specific cells in the immune system known as CD4 lymphocytes, forcing them to
abandon their intended function and instead produce thousands more copies of
the virus. The CD4 cells then die, releasing the newly made viruses, which go
on to repeat the process again and again over a timespan of up to 10 years
until CD4 levels are critically low and the immune system fails. (2)
If HIV is diagnosed early, a course of HIV medication known
as post-exposure prophylaxis (PEP) can prevent the virus from taking hold, as
long as it is taken within three days of first contact with the virus. If this
is unsuccessful, or more than three days have elapsed, medication will need to
be started as soon as possible to keep the virus under control. (2)
There is a wide range of HIV medication, also known as
antiretroviral medication, available and people with HIV must take a
combination of medicines daily to halt the progression of the disease and
maintain health. Antiretrovirals are grouped into the following categories:
nucleoside reverse transcriptase inhibitors
(NRTIs), which include zidovudine, abacavir and lamuvidine, and work by preventing the virus’s genetic material
from being copied
non-nucleoside reverse transcriptase inhibitors
(NNRTIs), including efavirenz, etravirine and rilpivirine, which work in the same way as NRTIs
protease inhibitors, such as ritonavir, saquinavir and atazanavir, which
prevent formation of new copies of the virus
integrase inhibitors, including dolutegravir and raltegravir, which prevent the hijacking of CD4 cells by the virus.
(4)
Other antiretroviral medications outside these categories
include enfuvirtide and maraviroc, which work in different ways
to the medications listed above. (4)
The promising news
Recent research by the Massachusetts Institute of Technology
has demonstrated that in the future it may be possible to reduce the frequency
of HIV medication dosing from daily to weekly by adopting a new formulation. Pigs
were administered various drugs in the form of a capsule containing a
star-shaped structure, which broke down much more slowly than a tablet or
standard capsule, releasing the medicine gradually over as long as two weeks.
Biotechnology company Lyndra is now planning to bring this success forward to
human trials over the next year. Such a formulation would be life-changing for
millions of people worldwide, making it easier to remember to take medication
as well as freeing them of the inconvenience of taking numerous drugs daily. It
is too early to know how long it may be before weekly HIV medication becomes
mainstream, but this is very exciting news indeed. (1)
Respect yourself and those around you - know your status
Follow these quick easy links to select your products:
HIV lab and home home-self test kits
Pre PrEP treatment test kit
PrEP Annual Test kit
Thinking of taking PrEP - read our informative blog to explain what you need to know.
References
BBC News (2018). ‘Once-a-week pill for HIV shows
promise in animals’. Available at: http://www.bbc.co.uk/news/health-42610315
NHS Choices. Causes [cited 9 January 2018].
Available at: https://www.nhs.uk/conditions/hiv-and-aids/causes/
NHS Choices. Overview [cited 9 January 2018].
Available at: https://www.nhs.uk/conditions/hiv-and-aids/#causes-of-hiv-infection
British National Formulary (version 4.2) [Mobile
application software]. Retrieved from: www.bnf.org
Author: Gabby Gallagher MPharm
Medically reviewed by: Superintendent pharmacist Margaret Hudson BSc(Hons)MRPharmS 11/01/18
Author: Gabby Gallagher MPharm
Medically reviewed by: Superintendent pharmacist Margaret Hudson BSc(Hons)MRPharmS 11/01/18
Posted in Men's Health, Sexual Health, Womens health