More than a million Americans are living with HIV. HIV is a virus that attacks a person’s immune system—specifically CD4 cells. These cells are a type of white blood cell, which play an important role in fighting infections. HIV damages CD4 cells and reduce their numbers. This makes the body more prone to infections and other diseases, such as certain types of cancer. Left untreated, HIV can lead to AIDS and be fatal. Fortunately, HIV drug therapy can help people with HIV live active, healthy lives for much longer than in the past.
Evidence shows early HIV treatment—regardless of CD4 count—leads to fewer complications and possibly even deaths. As a result, current expert guidelines recommend starting HAART (highly active antiretroviral therapy) for anyone with HIV. HAART with at least three drugs is standard care for HIV infection. There are several classes of HIV drugs doctors can use when designing HAART:
- Nucleoside reverse transcriptase inhibitors (NRTIs). These drugs block reverse transcriptase, an enzyme the virus needs to make new viruses. NRTIs block new virus production by inserting themselves into the virus’s DNA as it tries to copy itself. NRTIs were the first class of HIV drugs. In general, an initial HAART regimen will include two of these drugs.
- Non-nucleoside reverse transcriptase inhibitors (NNRTIs). This class binds to reverse transcriptase and changes the enzyme in way that makes it unable to function. Doctors may use an NNRTI as the third drug in an initial HAART regimen.
- Protease inhibitors (PIs). These drugs block protease, another enzyme the virus needs to reproduce. PIs can be part of an initial HAART regimen. However, they need the addition of a pharmacokinetic enhancer—a drug that boosts the effects of PIs on HIV.
- Integrase strand transfer inhibitors (INSTIs). INSTIs—or simply integrase inhibitors—block HIV from making copies of itself. HIV inserts its DNA into the CD4 cell’s DNA in order to replicate. Integrase inhibitors block the HIV enzyme that allows the transfer. INSTIs can be the third drug in an initial HAART regimen.
- Entry inhibitors. These drugs are also known as CCR5s (chemokine coreceptor antagonists). They block a protein—CCR5—on the surface of CD4 cells that the virus needs to get inside the cell. This prevents the virus from entering. Only certain strains of HIV use this protein. A blood test can tell your doctor if your HIV strand will respond to this class.
- Fusion inhibitors. These drugs prevent HIV from merging with the cell membrane of CD4 cells. This prevents the virus from entering the cell. This class is not currently recommended as first-line treatment. Instead, it is an option for treatment-experienced patients needing to change regimens.
- Pharmacokinetic enhancers. This class boosts the effectiveness of other drugs. They accomplish this by interfering with the breakdown of the other drug. This increases the blood levels of the drug.
Your doctor will consider your other health conditions, ease of taking the regimen of HIV drugs, and drug side effects and interactions when deciding on the best treatment for you. It is possible to transmit a drug-resistant virus. Your doctor will find out whether you have a wild-type virus (naturally occurring virus) or a drug-resistant one (mutated virus).
Here are 10 commonly prescribed HIV drugs:
1. Atripla (efavirenz + tenofovir + emtricitabine) combines an NNRTI and two NRTIs into one medication. The usual dose is once daily on an empty stomach—one hour before or two hours after a meal. Dizziness, diarrhea and tiredness are common side effects. Serious, life-threatening side effects are also possible, such as liver problems and a buildup of lactic acid in the blood.
2. Complera (rilpivirine + tenofovir + emtricitabine) combines an NNRTI and two NRTIs. The usual dose is once daily with a meal. Strange dreams, trouble sleeping, depressed mood, headache, and digestive problems are common. Serious liver problems and lactic acid buildup in the blood can occur.
3. Genvoya, Stribild (elvitegravir + cobicistat + tenofovir + emtricitabine) combines an INSTI, a pharmacokinetic booster, and two NRTIs. You usually take it once a day with food. Headache, nausea, and diarrhea are common side effects. Like Atripla and Complera, serious liver problems and lactic acid buildup in the blood are possible.
4. Isentress (raltegravir) is an INSTI you usually take twice a day. Nausea, headache, dizziness and fatigue are common side effects. Although rare, muscle breakdown leading to kidney failure may occur.
5. Norvir (ritonavir) is a PI you usually take twice daily with meals. Digestive side effects are common, as are headache and burning or tingling sensations. Norvir can also cause serious side effects and drug interactions. Tell your doctor and your pharmacist about all of your medications.
6. Prezista (darunavir) is a PI you usually take with ritonavir either once or twice a day. Ritonavir acts as a pharmacokinetic booster. Digestive problems, headache, and changes in body fat are common side effects. Severe skin reactions and liver problems are also possible.
7. Tivicay (dolutegravir) is an INSTI you take once or twice a day. Headache, fatigue, sleep problems, and changes in body fat are common side effects. Serious liver problems are also possible.
8. Triumeq (dolutegravir + abacavir + lamivudine) combines an INSTI and two NRTIs. The usual dose is once daily. Headache, fatigue, sleep problems, and changes in body fat are common side effects. It is also possible to have serious side effects, including a serious allergic reaction, liver problems, and a buildup of lactic acid in the blood.
9. Truvada (emtricitabine + tenofovir) combines two NRTIs. The usual dose is once daily. Abnormal dreams, trouble sleeping, depressed mood, headache, and dizziness are common side effects. Like other NRTI combinations, liver problems and lactic acidosis buildup in the blood is also possible.
10. Vemlidy, Viread (tenofovir) is an NRTI you usually take once a day. Digestive problems, fatigue, headache, depressed mood, sleep problems, and changes in body fat are common side effects. Like other NRTIs, serious side effects are possible, including liver problems and lactic acid buildup in the blood.
Once you and your doctor agree on a regimen, take every dose every day. This will decrease the risk of developing a drug-resistant virus. If you are having side effects, talk with your doctor. Many common side effects are mild and go away or improve with time. If side effects start to affect your health and quality of life, it may be time to consider another regimen. Serious side effects are also a sign that a change may be necessary. Talk with your doctor before stopping any of your HIV medicines.
Researchers continue to look for new HIV treatments. They are studying new drugs in the current classes, as well as new combinations of drugs. There are also studies looking at new drug classes and the use of monoclonal antibodies (biologics) to fight the disease. Talk with your doctor if you are interested in a clinical trial.
