What Is Etravirine?
Etravirine is a drug used as part of antiretroviral therapy (ART). It is also called Intelence. It is manufactured by Tibotec Pharmaceuticals.
Etravirine is a non-nucleoside reverse transcriptase inhibitor (a "non-nuke" or NNRTI). These drugs stop HIV from multiplying by preventing the reverse transcriptase enzyme from working. This enzyme changes HIV's genetic material (RNA) into the form of DNA. This step has to occur before HIV's genetic code gets inserted into an infected cell's genetic codes.
Who Should Take It?
Etravirine was approved in 2008 as an antiretroviral drug (ARV) for people with HIV infection. Etravirine is intended for use by people who have already used several combinations of drugs to fight HIV. It has not been studied in older adults. In 2012 the FDA approved Etravirine for people between 6 and 18 years old who have already used other antiviral medications and who weigh at least 35 pounds (16 kg).
There are no absolute rules about when to start ART. You and your health care provider should consider your CD4 cell count, your viral load, any symptoms you are having, and your attitude about taking HIV medications. Fact Sheet 404 has more information about guidelines for the use of ARVs.
If you take etravirine with other ARVs, you can reduce your viral load to extremely low levels, and increase your CD4 cell counts. This should mean staying healthier longer.
What About Drug Resistance?
Many new copies of HIV are mutations. They are slightly different from the original virus. Some mutations can keep multiplying even when you are taking an ARV. When this happens, the drug will stop working. This is called "developing resistance" to the drug. See Fact Sheet 126 for more information on resistance.
Sometimes, if your virus develops resistance to one drug, it will also have resistance to other ARVs. This is called "cross-resistance." Cross-resistance between efavirenz, delavirdine and nevirapine (all NNRTIs) develops very easily. If you develop resistance to one of these NNRTIs, you probably won't be able to use any of them in your ART. However, etravirine has shown that it can control HIV that has developed some resistance to other NNRTIs.
Resistance can develop quickly. It is very important to take ARVs according to instructions, on schedule, and not to skip or reduce doses.
How Is It Taken?
Etravirine is taken by mouth as a tablet. The normal adult dose is 400 milligrams (mg) a day. Etravirine was originally available in 100 mg tablets. In 2010, a 200 mg tablet was approved. You will take either 1 or 2 tablets, twice a day. Dosing for children and adolescents is based on body weight. A 25 mg tablet is now available.
It is recommended that you take etravirine following a meal. Do not take it on an empty stomach. If you have trouble swallowing etravirine, you can dissolve the tablets in water.
No dose adjustments are recommended for patients with mild liver problems or with kidney problems.
What Are the Side Effects?
When you start any ART, you may have temporary side effects such as headaches, high blood pressure, or just feeling ill. These side effects usually get better or disappear over time.
The most common side effects are rash and nausea. Rashes usually occurred during the second week of treatment with etravirine. In rare cases the rash can be severe, even fatal. This reaction is called Stevens-Johnson syndrome. Patients should stop taking etravirine immediately if they have a severe rash. Some patients also experienced abdominal pain and vomiting.
Patients who switched to etravirine saw improvements in their blood fats (see Fact Sheet 123).
How Does It React With Other Drugs?
Etravirine can interact with other drugs or supplements that you are taking. These interactions can change the amount of each drug in your bloodstream and cause an under- or overdose. New interactions are being identified all the time.
Drugs to watch out for include other ARVs, including all protease inhibitors. Also be careful with drugs to treat tuberculosis (see Fact Sheet 518), for erectile dysfunction (such as Viagra), for heart rhythm (antiarrhythmics) or angina. Interactions are also possible with several drugs to lower cholesterol. Make sure that your health care provider knows about ALL drugs and supplements you are taking.
Etravirine does not appear to affect blood levels of oral contraceptives, antacids or methadone. Etravirine slightly decreases levels of buprenorphine. Although no dose adjustments are necessary, patients taking etravirine and buprenorphine should be monitored carefully.
The herb St. John's Wort (see Fact Sheet 729) lowers the blood levels of some non-nucleoside reverse transcriptase inhibitors. Do not take it with etravirine.