Non-nucleoside reverse transcriptase inhibitor resistant HIV-1 infection

Non-nucleoside Reverse Transcriptase Inhibitor Resistant HIV-1 Infection

Non-nucleoside reverse transcriptase inhibitors (NNRTIs) are a class of drugs used to treat HIV that block the action of reverse transcriptase, a key enzyme needed for the virus to replicate. If the virus becomes resistant to the drug, the HIV-1 treatment will no longer be effective.

It is estimated that approximately 10-20% of people with HIV develop a resistance to NNRTIs over time and this can negatively affect treatment outcomes. People who are at higher risk for developing resistance include those who have a high HIV viral load, have not previously been on HIV treatment, or are taking a new NNRTI medication or a combination of medications.

Causes of NNRTI Resistance

NNRTI resistance can be caused by several different things, including:

• The virus can mutate in a way that renders the drug ineffective.
• Poor adherence to taking the medications.
• Incomplete absorption of the drug.
• Insufficient drug levels in the body.
• Pre-existing resistance due to previous exposure.

Detecting NNRTI Resistance

There are several ways to detect NNRTI resistance. The most common method is through a genotypic resistance test, which looks for HIV mutations that can confer resistance to the NNRTI. This test is usually performed when a patient does not respond to their current antiviral therapy.

There is also a phenotypic resistance test, which measures the susceptibility of the virus to a drug directly in blood samples. This test is more expensive and time consuming, but provides more detailed information about the susceptibility of the virus to medications.

Managing NNRTI Resistance

People with NNRTI resistance should talk to their doctor about possible treatment options. If their current regimen is not working, they may need to switch to a different class of antiretroviral medication. Some newer drugs, such as integrase inhibitors, may be more effective at fighting the virus.

Adherence to medications is also important in order to prevent and manage resistance. If you have any problems with side effects or taking your medications as prescribed, talk to your doctor or a healthcare provider for help.