Truvada fails in a smaller group of the population commonly known as MSM. Recently, these cases have been more and rarer but not fully ruled out. It’s a shocking reality but something not to be feared. Still, Truvada provides protection up to 99% or more for an individual following the drug’s prescription.
It’s time to get understand the root reasons for acquiring HIV even with a committed PrEP prescription. At HIVPrEP, we explore this condition with an amiable discussion to let you know how to use the PrEP medication as well as what preventive measures to consider while using the PrEP drug.
Is PrEP right for you? Tenofovir/emtricitabine is a drug combination with the brand name Truvada. It’s a daily pill prescribed for individuals who are at very high risk for HIV. These medications lower the chances of getting infected by stopping the virus from taking hold and multiplying in your blood cells .
It’s prescribed for:
PrEP meds are highly effective for preventing HIV, providing a protection level up to 99% (or more than 70% for individuals who inject drugs) if used as prescribed. On the contrary, the same drug is much less effective if not administered consistently or as prescribed.
There are a few known incidences where PrEP HIV resistant (virus-resistant) to the use of tenofovir/emtricitabine. Very few men acquired the virus while on the PrEP medication with Truvada – even while adhering to the dose prescription as proven from the three test samples of hair and dried blood spots.
Performing a sexual act with a person who has a fully suppressed virus (viral load) is virtually uninfectious. But some men can get the infection even in such conditions. This is most evident in MSMs contracting HIV from condomless sex while on PrEP (in perfect adherence to the daily Truvada regimen).
Drug resistance can happen due to multiple resistance mutations (cross-resistance), including the use of Truvada’s tenofovir and emtricitabine medicines. As a matter of fact, this condition of having a virus that is resistant to both of the antiretrovirals existing in tenofovir/emtricitabine is extremely rare.
From the research done by CROI 2018 based on King County, 0.3% (only 12 people) of the total sample population of 6,963 has high-level resistance to both the medicines in Truvada . That means this percentage contracted virus not because of non-adherence but due to the fact that the virus was resistant to both emtricitabine and tenofovir.
Another study in macaques depicts that the tenofovir-resistant virus but not the emtricitabine-resistant virus can lead to a breakthrough virus infection despite the two-drug combination (TDF/FTC) for PrEP. FTC resistance with M184V/I occurs more frequently than TDF resistance with K65R in seroconverts .
There is evidence of individuals who acquired the virus even with full adherence to PrEP. One is from New York City and another – a 43-year-old Canadian. Both men are in the MSM category .
There are also other studies that show cases of this rare PrEP failure including a man from California. Others having been observed in North Carolina, the Netherlands, and Thailand. And maybe there are other cases not known to clinicians .
As there are cases arising rarely, this condition is prevailing. Although the benefit of preventing HIV-1 virus infections with FTC/TDF PrEP far outweighs the possible risk of drug-resistant acquisition, we should not fear virus resistance from this drug for PrEP.
It’s important to administer PrEP only if you have been fully proven to be HIV- negative. Drug resistance is something that’s strange and if detected earlier, there is a possibility to prevent the spread of HIV-1 resistance to TDF/FTC.
The first step to take before starting PrEP is to make sure you are confirmed HIV-negative. Adherence to the drug’s prescription is a must. In most cases, resistance to PrEP drugs is only a risk if you are infected with the virus.
Although it is required to consistently take PrEP, a person may contract HIV-1 during a break from PrEP and from not testing their HIV status prior to restarting Truvada medication.
When a person misses too many FTC/TDF doses (inconsistent taking of the drug), it may contribute to low levels of Truvada’s active substance in the body making it ineffective to fully prevent virus acquisition. In this case, the continual exercise of unprotected sex may make the virus escape the protection and finally infect the blood. Continual use of PrEP while being infected may develop virus resistance to ARV.
TDF/FTC is the only approved medication for PrEP. Although there exist drug-resistant strains of HIV, they’re very rare. Truvada still remains highly effective for both PrEP and ART.
The WHO is raising awareness and a program is active until 2021 to prevent, monitor, and effectively respond to the emergence of HIV-1 drug resistance .
In the UK, PrEP is available in various ways including the NHS sexual health clinics, PrEP impact trial, local clinics…
Treating HIV involves use of a combination of antiretroviral medicines. Truvada has been around for a very long time and…