Search tips
Search criteria 


Logo of cmajCMAJ Information for AuthorsCMAJ Home Page
CMAJ. 2016 September 20; 188(13): 971.
PMCID: PMC5026515

Single-tablet antiretroviral treatment (once daily)

Single-tablet antiretroviral treatment taken once daily improves adherence and quality of life compared with multiple-pill regimens

Current guidelines recommend combination antiretroviral treatment for all patients with HIV infection.1,2 The backbone of this treatment regimen is a dual nucleoside reverse transcriptase inhibitor combination, typically tenofovir/emtricitabine or abacavir/lamivudine, which is combined with a non-nucleoside reverse transcriptase inhibitor, integrase strand-transfer inhibitor or boosted protease inhibitor.3 A meta-analysis of randomized controlled trials (RCTs) showed higher pill burden is inversely associated with adherence to combination antiretroviral treatment and virologic suppression, which provides a rationale for using single-tablet regimens.4

Abacavir/lamivudine/dolutegravir has the highest genetic barrier to resistance; however, there is a risk of hypersensitivity

Abacavir/lamivudine/dolutegravir is recommended as first-line treatment based on RCT evidence.1,2 Abacavir is associated with severe hypersensitivity reactions in patients with the HLA-B5701 allele.1,3 Pretreatment genetic testing is indicated, and abacavir should be avoided if test results are positive for the presence of the allele.2,3 Dolutegravir is an integrase strand-transfer inhibitor with minimal adverse effects and a high genetic barrier to resistance.13

Tenofovir/emtricitabine/efavirenz is associated with neuropsychiatric adverse effects

Tenofovir/emtricitabine forms the backbone in three of four single-tablet regimens and is the preferred treatment for HIV/hepatitis B virus co-infection.1 Tenofovir/emtricitabine/efavirenz is recommended only as an alternative regimen, because efavirenz is associated with neuropsychiatric symptoms and may increase suicidality.1,2 Tenofovir may cause renal toxicity and osteoporosis.13

Tenofovir/emtricitabine/rilpivirine is less effective in patients with pretreatment HIV viral loads greater than 100 000 copies/mL or CD4 counts less than 200 cells/μL

Tenofovir/emtricitabine/rilpivirine should not be prescribed as initial treatment for these patients but is a recommended alternative regimen.13 Rilpivirine is a non-nucleoside reverse transcriptase inhibitor with less central nervous system toxicity than efavirenz.1 Adequate absorption requires administration in conjunction with a high-energy meal (> 400 kcal).1 Rilpivirine should not be prescribed to patients taking proton pump inhibitors and should be prescribed with caution in patients taking other acid-lowering drugs.1,3

Tenofovir/emtricitabine/elvitegravir/cobicistat is well-tolerated but associated with multiple drug interactions

Tenofovir/emtricitabine/elvitegravir/cobicistat is recommended first-line therapy based on RCT evidence.1 It is contraindicated if creatinine clearance is less than 70 mL/min.1,3 Elvitegravir, which is an integrase strand-transfer inhibitor, has a lower genetic barrier to resistance than dolutegravir.1,2 Cobicistat is a cytochrome P450 3A4 inhibitor that acts to increase elvitegravir levels in plasma.2 However, it has the potential for multiple drug interactions (e.g., with statins and rifampin).13

CMAJ invites submissions to “Five things to know about …” Submit manuscripts online at


Competing interests: None declared.

This article has been peer reviewed.


1. Panel on Antiretroviral Guidelines for Adults and Adolescents. Guidelines for the use of antiretroviral agents in HIV-1 infected adults and adolescents. Bethesda (MD): Department of Health and Human Services; 2014. Available: (accessed 2015 Oct. 16).
2. Günthard HF, Aberg JA, Eron JJ, et al. Antiretroviral treatment of adult HIV infection: 2014 recommendations of the International Antiviral Society — USA Panel. JAMA 2014;312:410–25. [PubMed]
3. Gandhi M, Gandhi RT. Single-pill combination regimens for treatment of HIV-1 infection. N Engl J Med 2014;371:248–59. [PubMed]
4. Nachega JB, Parienti J, Uthman OA, et al. Lower pill burden and once-daily antiretroviral treatment regimens for HIV infection: a meta-analysis of randomized controlled trials. Clin Infect Dis 2014; 58:1297–307. [PMC free article] [PubMed]

Articles from CMAJ : Canadian Medical Association Journal are provided here courtesy of Canadian Medical Association