From WikiProjectMed
Jump to navigation Jump to search
Efavirenz/emtricitabine/tenofovir disoproxil
Combination of
Efavirenznon-nucleoside reverse transcriptase inhibitor
Emtricitabinenucleoside analog reverse transcriptase inhibitor
Tenofovir disoproxilnucleotide analog reverse transcriptase inhibitor
Trade namesAtripla, Viraday, others
Clinical data
  • AU: D[1]
  • US: D (Evidence of risk)[1]
Routes of
By mouth
Defined daily dosenot established[2]
External links
AHFS/Drugs.comProfessional Drug Facts
License data
Legal status
  • UK: POM (Prescription only) [3]
  • US: ℞-only
  • In general: ℞ (Prescription only)

Efavirenz/emtricitabine/tenofovir, sold under the brand name Atripla among others, is a fixed-dose combination medication used to treat HIV/AIDS.[4][5] It contains efavirenz, emtricitabine, and tenofovir disoproxil.[4][5] It can be used by itself or together with other antiretroviral medications.[4] It is taken by mouth once a day.[4][5]

Common side effects include headache, trouble sleeping, sleepiness, and unsteadiness.[6] Serious side effects may include high blood lactate levels, psychiatric symptoms, and enlargement of the liver.[6] It should not be used in children.[4] If used during the first trimester of pregnancy harm to the baby may occur.[6]

Efavirenz/emtricitabine/tenofovir was approved for medical use in the United States in 2006,[6] and in the European Union in 2007.[5] It is on the World Health Organization's List of Essential Medicines.[7] The wholesale cost in the developing world is about US$10.71–14.19 per month as of 2014.[8] The wholesale cost in the United States is about $2308.20 a month as of 2016, while in the United Kingdom it costs the NHS GB£532.87 per month as of 2015.[9][10]

Medical uses

Combining the three drugs into a single, once-daily pill reduces pill burden and simplifies dosing schedules, and therefore has the potential to increase adherence to antiretroviral therapy.


The defined daily dose is not established[2]


People who have shown strong hypersensitivity to efavirenz, should not take efavirenz/emtricitabine/tenofovir. Drugs that are contraindicated are: voriconazole, ergot derivative drugs, benzodiazepines midazolam and triazolam, calcium channel blocker bepridil, cisapride, pimozide and St. John's wort (Hypericum perforatum). Breastfeeding is also contraindicated.[6]

Side effects

Common side effects of efavirenz/emtricitabine/tenofovir are tiredness, dizziness, gastrointestinal distress, and skin discoloration. More severe side effects are hallucinations, sleeplessness and depression.[11]

Recommended dosage for efavirenz/emtricitabine/tenofovir is one tablet at or before bedtime. Side effects can be reduced if it is taken on an empty stomach. People with kidney or liver problems can take one tablet by mouth once a day. However, people whose CrCl levels are less than 50ml/min should not follow this dosage. Instead, patients should be prescribed drug components of the fixed-dose combinations while adjusting TDF and FTC doses according to the patient's CrCl levels.[12]


Medications that should not be taken with efavirenz/emtricitabine/tenofovir include bepridil, midazolam, pimozide, triazolam, or ergot derivatives. Additionally, St. John's wort is known to reduce the effectiveness of efavirenz/emtricitabine/tenofovir, resulting in increased viral load and possible resistance to efavirenz/emtricitabine/tenofovir.[13]

Mechanism of action

Efavirenz is a non-nucleoside reverse transcriptase inhibitor (NNRTI) of HIV-1. Emtricitabine is a nucleoside reverse transcriptase inhibitor (NRTI) of HIV-1. Tenofovir is a nucleotide reverse transcriptase inhibitor of HIV-1, and it can be classified as an NtRTI. These three drugs work in combination to target the HIV reverse transcriptase protein in three ways, which reduces the virus's capacity to mutate.[6]

In combination studies there were synergistic antiviral effects observed between emtricitabine and efavirenz, efavirenz and tenofovir, and emtricitabine and tenofovir.[6]


Efavirenz/emtricitabine/tenofovir was approved in the United States as a once-daily tablet to treat HIV in 2006. The main advantage of the new drug was that it could be taken once daily and reduce the overall stress in an antiretroviral regimen.[14] There is no generic version available in the United States. An equivalent two pill regimen is available in developing countries at a price of about US$1.00 per day, as Gilead Sciences has licensed the patents covering emtricitabine/tenofovir to the Medicines Patent Pool[15] and Merck and Co makes efavirenz available in developing countries at a reduced price.[16]

Society and culture

It is the first multi-class antiretroviral drug available in the United States and represents the first collaboration between two U.S. pharmaceutical companies to combine their patented anti-HIV drugs into one product.[17]

In North America and Europe, Atripla is marketed jointly by Gilead Sciences and Bristol-Myers Squibb, but in much of the developing world, marketing and distribution is handled by Merck & Co.[18]


Atripla is a pink, film-coated tablet with "123" impressed on one side.


  1. 1.0 1.1 "Efavirenz / emtricitabine / tenofovir (Atripla) Use During Pregnancy". Drugs.com. 27 July 2018. Archived from the original on 28 October 2020. Retrieved 31 March 2020.
  2. 2.0 2.1 "WHOCC - ATC/DDD Index". www.whocc.no. Archived from the original on 27 November 2020. Retrieved 20 September 2020.
  3. "Atripla 600 mg/200 mg/245 mg film coated tablets - Summary of Product Characteristics (SmPC)". (emc). 2 March 2020. Archived from the original on 10 August 2020. Retrieved 31 March 2020.
  4. 4.0 4.1 4.2 4.3 4.4 World Health Organization (2009). Stuart MC, Kouimtzi M, Hill SR (eds.). WHO Model Formulary 2008. World Health Organization. p. 160. hdl:10665/44053. ISBN 9789241547659.
  5. 5.0 5.1 5.2 5.3 "Atripla EPAR". European Medicines Agency (EMA). 7 July 2008. Archived from the original on 12 August 2020. Retrieved 31 March 2020.
  6. 6.0 6.1 6.2 6.3 6.4 6.5 6.6 "Atripla- efavirenz, emtricitabine, and tenofovir disoproxil fumarate tablet, film coated". DailyMed. 5 November 2019. Archived from the original on 30 November 2020. Retrieved 3 February 2020.
  7. World Health Organization (2019). World Health Organization model list of essential medicines: 21st list 2019. Geneva: World Health Organization. hdl:10665/325771. WHO/MVP/EMP/IAU/2019.06. License: CC BY-NC-SA 3.0 IGO.
  8. "Efavirenz + Emtricitabine + Tenofovir Df". International Drug Price Indicator Guide. Archived from the original on 22 January 2018. Retrieved 28 November 2016.
  9. "NADAC as of 2016-12-07 | Data.Medicaid.gov". Centers for Medicare and Medicaid Services. Archived from the original on 21 December 2016. Retrieved 12 December 2016.
  10. British National Formulary (BNF) 69 (69 ed.). Pharmaceutical Press. 2015. p. 423. ISBN 9780857111562.
  11. "Possible Side Effects of Atripla". Bristol-Myers Squibb & Gilead Sciences, LLC. 2008. Archived from the original on 2009-03-03. Retrieved 2010-01-03.
  12. "Panel on Antiretroviral Guidelines for Adults and Adolescents. Guidelines for the use of antiretroviral agents in HIV-1-infected adults and adolescents" (PDF). Archived (PDF) from the original on 1 November 2016. Retrieved 19 October 2012.
  13. "Medicines You Should Not Take with Atripla". Bristol-Myers Squibb & Gilead Sciences, LLC. 2008. Archived from the original on 2009-12-17. Retrieved 2010-01-03.
  14. "HIV Medication List - AIDS Drugs:". AIDS Drugs HIV Reference. aidsdrugsonline. 2009. Archived from the original on December 26, 2008. Retrieved 2010-01-03.
  15. "Medicines Patent Pool Signs Licence Agreement with Gilead to Increase Access to HIV/AIDS Medicines". Archived from the original on 2014-02-19.
  16. "HIV & AIDS Information :: Merck cuts price of efavirenz for developing countries again". Archived from the original on 2014-02-19.
  17. "Search for Tradename: Atripla". Drug Patent Watch. 2010. Archived from the original on 2011-08-15. Retrieved 2010-01-03.
  18. "Merck To Register, Lower Cost Of Antiretroviral Atripla In Developing Countries". Medical News Today. 23 February 2007. Archived from the original on 2010-07-03. Retrieved 2010-01-03.

External links