HIV drugs, also called antiretroviral medications, are lumped into different classes based on the kinds of methods the drug will use the attack the virus. Doctors often use drugs from more than one class for their patients’ treatment regimen, as this helps to improve their effectiveness and stop the chance of drug resistance.
What are the different HIV classes, and how do they work?
Entry and Fusion Inhibitors (EIs) – Drugs of this class keep the HIV from fusing, binding and getting into the T cells. EIs are used along with other HIV drugs.
Integrase Strand Transfer Inhibitors (INSTIs) – The drugs of this class block integrase, which is an enzyme HIV must have to replicate. HIV will use integrase to add its viral DNA to the T cells DNA. Blocking the process means HIV cannot replicate. They are taken in conjunction with other HIV meds.
Nucleoside Reverse Transcriptase Inhibitors (NRTIs) – Drugs here will block reverse transcriptase, which is the enzyme HIV must have to replicate. The virus will use the reverse transcriptase to change the RNA it has into DNA, which stops the process and the HIV from reproducing. These drugs are taken with other HIV drugs.
Nonnucleoside Reverse Transcriptase Inhibitors (NNRTIs) – These drugs stop reverse transcriptase just like NRTIs but in another way. They are used simultaneously with their drugs.
Pharmacokinetic Enhancer/CYP3A Inhibitors (PKE) – These drugs increase the effectiveness of the antiretroviral medication. When two of them are taken simultaneously, the PKE slows the other drug’s breakdown, ensuring the drug to stay in the body longer at a higher level. These are used with other HIV drugs.
Post-Attachment Inhibitors (PAIs) – These drugs will bind to CD4 cells after the HIV attaches to them, but keep the HIV from getting into the cells. They are used with other HIV meds.
Protease Inhibitors (PIs) – The drugs in HIV class block protease activation, which is the enzyme HIV must have to grow. By blocking the protease, it stops the premature types of HIV from growing into a mature virus that can infect the T cells. These are used with other medication for HIV.
Single-Tablet Regimens (STRs) – These fixed-dose pills combine several anti-HIV meds into one tablet and are taken one time a day. These meds are not used with any HIV medication.