New HIV infections in the US continue to be on the rise, and like many other things, our QPOC communities continue to be disproportionately affected. With gay, bi, and queer men of color, and trans women of color being the most impacted by new infections.
Recently, there have been an increasing amount of conversations about Pre-Exposure Prophylaxis (PrEP), currently the daily pill regimen of the medication Truvada that can reduce a person’s risk of contracting HIV. Those conversations will, more often than not, focus on why PrEP is effective and only rarely discuss HOW it is effective, and often those conversations are full of language that is hard to follow. In response to this, we have created a quick, hopefully easily understandable, breakdown of the language that is often used when talking about HIV (which can be found below), as well as how Truvada, when used for PrEP, protects our cells from HIV replication.
So let’s break down how Truvada works in our bodies, this part may be filled with that language that is hard to follow that we were talking about. If you would like to know how Truvada works in the body, but aren’t interested in knowing the science behind it, feel free to skip to the next paragraph. Truvada works the same way in our bodies to prevent HIV as PrEP as it does when used to treat HIV. The major difference being that, when used to treat HIV, it is paired with other medications, as Truvada, by itself, is not a treatment for HIV. Both medications in Truvada, Emtricitabine and Tenofovir Disoproxil are nucleoside/nucleotide reverse transcriptase inhibitors (NRTI). When the reverse transcriptase enzyme, released by the HIV virus into our cells, is converting viral RNA into viral DNA it is using building blocks from inside the helper T-cell. NRTIs work by being very similar to, and taking the place of, those building blocks, except that NRTIs do not allow other building blocks to be connected to them. What this means is that, after they have been added into the viral DNA chain, the process cannot continue. This, in turn, forces the reverse transcriptase enzyme to stop converting viral RNA into viral DNA, keeping the new viral DNA from being created. HIV, as a result, is kept from replicating within your cells.
Another way to think about this is by thinking about the RNA and DNA compounds as building blocks like those in the picture above. When reverse transcriptase, released by HIV into our cells, is turning HIV RNA into HIV DNA, it is using the building blocks found in our cells. Each building block has ridges on its top that allows the next block to attach. The medications in Truvada work by being just like those building blocks, except that they do not have the ridges on top for the next block to attach. That means that reverse transcriptase can not continue to add additional building blocks to the chain causing it to stop production.
By taking the medication every day, a person ensures that their cells have enough of those NRTIs building blocks around to stop new HIV from replicating. It can take up to 7 days for NRTIs to build up in your system to offer the best protection during anal and vaginal sex, though some studies are showing that a higher dose of the medication over a longer period of time may be needed for vaginal sex to be as effective.
After learning about PrEP many people ask “How much does it cost?”
The answer to that is… It depends. Depending on where you live the full price of Truvada, without insurance or assistance, can be over $1,300, though very few people pay that. Some insurance companies cover the cost, and Gilead Sciences, Inc has an Insurance Assistance program which can help you navigate working with your insurance company and provider, as well as a Co-Pay Assistance Program that can help offset the cost. There are also organizations in Austin that can assist you in the process. The Center for Health Empowerment and the Kind Clinic both have their own providers and staff available to assist people who wish to access PrEP for low to no cost, as well as a number of other health services.
The next question many people have is “Is PrEP right for me?”
The answer to that is again, it depends. PrEP isn’t right for everyone. Like every medication some people experience side effects and some people experience these side effects more than others. Common side effects are some nausea and stomach discomfort, diarrhea, tiredness, headache, dizziness, depression, problems sleeping, abnormal dreams, and rash. For many people these side effects are temporary, but you should tell your healthcare provider if you have any side effects that causes you discomfort or do not go away. For some people there have been a reduction in kidney function and a loss of bone density, both of these are reversible should be noticed by your provider at your regular check up. and Your provider should also schedule regular check ups with you to discuss how the medication is working for you, as well at to run tests to check your kidney function and bone density and to make sure you have not contracted HIV while taking Truvada.
Truvada can also interact with other medications. It is important that you tell your provider about any medication you are taking before starting a new medication. It is also most effective if you remember to take it every day and pair it with other sexual health strategies. People should talk with their healthcare provider to discuss the pros and cons of starting and taking a medication. Remember, PrEP is not 100% effective, but by combining it with other sexual health strategies, people can significantly reduce their chances of contracting HIV. If you are interested in talking to a provider about PrEP, and how to you may be able to access it for low to no cost, contact Center for Health Empowerment or the Kind Clinic to schedule an appointment.
In order to better understand how HIV and medications like Truvada work we created this list with some definitions:
Retrovirus – a virus that contains single stranded RNA (genetic material) inside of it, instead of double stranded DNA. RNA and DNA are used by our cells as a set of instructions about how to build more cells. Below is a picture that shows the difference in how RNA and DNA look
PrEP (Pre-Exposure Prophylaxis) – a medicine you take before exposure to a virus to reduce your chances of contracting that virus. In reference to HIV it is, currently, a daily pill regimen that, if taken correctly, may reduce the risk of HIV infection by up to 92%.
PEP (Post-Exposure Prophylaxis) – a medicine regimen that begins after exposure to a virus to reduce the chance that the virus will be able to cause new infection. In reference to HIV is it a month long daily pill regimen that must be started within 72 hours of exposure, and may reduce your risk of HIV infection by up to 72%
Truvada – an antiretroviral, made by the company Gilead Sciences, Inc. that is used in combination with other medications to treat HIV. Also, it is, currently, the only medication approved for PrEP.
TasP (Treatment as Prevention) – the use of antiretroviral medication to help people living with HIV to achieve an undetectable viral load, which will lower the chances of HIV transmission to their sexual partners.
Undetectable – through the use of antiretroviral medications a person living with HIV may reach an undetectable level of the virus in their system. Studies have shown that people living with HIV who reach an undetectable viral load have much better health outcomes than those who do not. Reaching an undetectable viral load may also reduce the chances of passing the virus to others by up to 95%. Achieving an undetectable viral load status does not mean that a person is cured of HIV, as there is currently no cure for HIV.
Viral Load – is the amount of virus within a person’s body. Can also be used in a larger context such as community viral load, which is in reference to the impact of HIV on specific communities.
Adherence – in reference to medication, it is the ability of a person to take medication as prescribed.
Helper T-Cell – also known as CD4 cells, CD4+, or T-cells, are white blood cells that search out infectious or cancerous agents in our bodies and send a signal to other white blood cells that a response is needed.
Enzyme – A protein that helps start or speed up a chemical or biological process.
Now that we are all on the same page with definitions, let’s learn a little bit about the HIV replication cycle, which we will need to understand if we want to know how medications work.
There are 7 steps in the HIV replication cycle
Step 1: Entry – HIV attaches to the outside of a helper T-cell and merges with the cell, releasing its two single stranded viral RNA and three enzymes (reverse transcriptase, integrase, and protease) into the host cell.
Step 2: Reverse transcriptase – the enzyme reverse transcriptase takes the single strand viral RNA and converts it to double stranded viral DNA.
Step 3: Integration– the enzyme integrase takes the viral DNA and connects it to the DNA of the helper T-cell.
Step 4: Transcription – The helper T-cell’s own processes are used to read the new viral DNA and begin the process of creating more viral RNA.
Step 5: Translation – The new viral RNA once again uses the helper T-cell’s own processes to create the rest of the components needed to create new virus particles.
Step 6: Assembly – The new viral components begin to assemble at the edge of the helper T-cell, using the cell’s proteins to create a bud that will become the new HIV virus. The enzyme protease separates each of the viral components into individual proteins.
Step 7: Release – the new HIV particle is released from the host cell, where it will go on to infect a new helper T-cell and create more virus. Each infected helper T-cell can make millions of new virus particles before eventually being destroyed.