Efavirenz (Sustiva, Stocrin)
January 25, 2001; Updated
|Susa Coffey, MD|
| 1. ||Staszewski
Efavirenz plus zidovudine and lamivudine, efavirenz plus indinavir, and indinavir plus zidovudine and lamivudine in the treatment of HIV-1 infection in adults. Study 006 Team. N Engl J Med. 1999 Dec;341(25):1865-73
[PubMed ID: 10601505]
BACKGROUND: Efavirenz is a nonnucleoside reverse-transcriptase inhibitor of human immunodeficiency virus type 1 (HIV-1). We compared two regimens containing efavirenz, one with a protease inhibitor and the other with two nucleoside reverse-transcriptase inhibitors, with a standard three-drug regimen. METHODS: The study subjects were 450 patients who had not previously been treated with lamivudine or any nonnucleoside reverse-transcriptase inhibitor or protease inhibitor. In this open-label study, patients were randomly assigned to one of three regimens: efavirenz (600 mg daily) plus zidovudine (300 mg twice daily) and lamivudine (150 mg twice daily); the protease inhibitor indinavir (800 mg every eight hours) plus zidovudine and lamivudine; or efavirenz plus indinavir (1000 mg every eight hours). RESULTS: Suppression of plasma HIV-1 RNA to undetectable levels was achieved in more patients in the group given efavirenz plus nucleoside reverse-transcriptase inhibitors than in the group given indinavir plus nucleoside reverse-transcriptase inhibitors (70 percent vs. 48 percent, P<0.001). The efficacy of the regimen of efavirenz plus indinavir was similar (53 percent) to that of the regimen of indinavir, zidovudine, and lamivudine. CD4 cell counts increased significantly with all combinations (range of increases, 180 to 201 cells per cubic millimeter). More patients discontinued treatment because of adverse events in the group given indinavir and two nucleoside reverse-transcriptase inhibitors than in the group given efavirenz and two nucleoside reverse-transcriptase inhibitors (43 percent vs. 27 percent, P=0.005). CONCLUSIONS: As antiretroviral therapy in HIV-1-infected adults, the combination of efavirenz, zidovudine, and lamivudine has greater antiviral activity and is better tolerated than the combination of indinavir, zidovudine, and lamivudine.
| 2. ||Robbins
GK, De Gruttola
L, van der Horst
MS; AIDS Clinical Trials Group 384 Team.|
Comparison of sequential three-drug regimens as initial therapy for HIV-1 infection. N Engl J Med. 2003 Dec;349(24):2293-303
[PubMed ID: 14668455]
BACKGROUND: The optimal sequencing of antiretroviral regimens for the treatment of infection with human immunodeficiency virus type 1 (HIV-1) is unknown. We compared several different antiretroviral treatment strategies. METHODS: This multicenter, randomized, partially double-blind trial used a factorial design to compare pairs of sequential three-drug regimens, starting with a regimen including zidovudine and lamivudine or a regimen including didanosine and stavudine in combination with either nelfinavir or efavirenz. The primary end point was the length of time to the failure of the second three-drug regimen. RESULTS: A total of 620 subjects who had not previously received antiretroviral therapy were followed for a median of 2.3 years. Starting with a three-drug regimen containing efavirenz combined with zidovudine and lamivudine (but not efavirenz combined with didanosine and stavudine) appeared to delay the failure of the second regimen, as compared with starting with a regimen containing nelfinavir (hazard ratio for failure of the second regimen, 0.71; 95 percent confidence interval, 0.48 to 1.06), as well as to delay the second virologic failure (hazard ratio, 0.56; 95 percent confidence interval, 0.29 to 1.09), and significantly delayed the failure of the first regimen (hazard ratio, 0.39) and the first virologic failure (hazard ratio, 0.34). Starting with zidovudine and lamivudine combined with efavirenz (but not zidovudine and lamivudine combined with nelfinavir) appeared to delay the failure of the second regimen, as compared with starting with didanosine and stavudine (hazard ratio, 0.68), and significantly delayed both the first and the second virologic failures (hazard ratio for the first virologic failure, 0.39; hazard ratio for the second virologic failure, 0.47), as well as the failure of the first regimen (hazard ratio, 0.35). The initial use of zidovudine, lamivudine, and efavirenz resulted in a shorter time to viral suppression. CONCLUSIONS: The efficacy of antiretroviral drugs depends on how they are combined. The combination of zidovudine, lamivudine, and efavirenz is superior to the other antiretroviral regimens used as initial therapy in this study.
| 3. ||Gallant
AK; 903 Study Group.|
Efficacy and safety of tenofovir DF vs stavudine in combination therapy in antiretroviral-naive patients: a 3-year randomized trial. JAMA. 2004 Jul;292(2):191-201
[PubMed ID: 15249568]
CONTEXT: Tenofovir disoproxil fumarate (DF) is a once-daily nucleotide analogue reverse transcriptase inhibitor. OBJECTIVE: To evaluate the efficacy and safety of tenofovir DF compared with stavudine in antiretroviral-naive patients. DESIGN, SETTING, AND PARTICIPANTS: A prospective, randomized, double-blind study conducted at 81 centers in the United States, South America, and Europe from June 9, 2000, to January 30, 2004. A total of 753 patients infected with HIV who were antiretroviral naive were screened and 602 patients entered the study. INTERVENTION: Patients were randomized to receive either tenofovir DF (n = 299) or stavudine (n = 303), with placebo, in combination with lamivudine and efavirenz. MAIN OUTCOME MEASURE: Proportion of patients with HIV RNA levels of less than 400 copies/mL at week 48. RESULTS: In the primary intent-to-treat analysis in which patients with missing data or who added or switched antiretroviral medications before week 48 were considered as failures, the proportion of patients with HIV RNA of less than 400 copies/mL at week 48 was 239 (80%) of 299 in patients receiving tenofovir DF and 253 (84%) of 301 in patients receiving stavudine (95% confidence interval, -10.4% to 1.5%), exceeding the predefined -10% limit for equivalence. However, equivalence was demonstrated in the secondary analyses (HIV RNA <50 copies/mL) at week 48 and through 144 weeks. Virologic failure was associated most frequently with efavirenz and lamivudine resistance. Through 144 weeks, the K65R mutation emerged in 8 and 2 patients in the tenofovir DF and stavudine groups, respectively (P =.06). A more favorable mean change from baseline in fasting lipid profile was noted in the tenofovir DF group at week 144: for triglyceride levels (+1 mg/dL for tenofovir DF [n = 170] vs +134 mg/dL for stavudine [n = 162], P<.001), total cholesterol (+30 mg/dL [n = 170] vs +58 mg/dL [n = 162], P<.001), direct low-density lipoprotein cholesterol (+14 mg/dL [n = 169] vs +26 mg/dL [n = 161], P<.001), and high-density lipoprotein cholesterol (+9 mg/dL [n = 168] vs +6 mg/dL [n = 154], P =.003). Investigator-reported lipodystrophy was less common in the tenofovir DF group compared with the stavudine group (9 [3%] of 299 vs 58 [19%] of 301, P<.001). The number of bone fractures and the renal safety profile were similar between the 2 groups. CONCLUSIONS: Through 144 weeks, the combination of tenofovir DF, lamivudine, and efavirenz was highly effective and comparable with stavudine, lamivudine, and efavirenz in antiretroviral-naive patients. However, tenofovir DF appeared to be associated with better lipid profiles and less lipodystrophy.
| 4. ||DeJesus
TR; CNA30024 Study Team.|
Abacavir versus zidovudine combined with lamivudine and efavirenz, for the treatment of antiretroviral-naive HIV-infected adults. Clin Infect Dis. 2004 Oct;39(7):1038-46
[PubMed ID: 15472858]
BACKGROUND: Zidovudine, lamivudine, and efavirenz comprise a highly effective and well-tolerated triple regimen for antiretroviral-naive patients. Evaluating other unique nucleoside reverse-transcriptase inhibitor (NRTI) combinations for long-term viral suppression is desirable. METHODS: This multicenter, randomized, double-blind noninferiority clinical trial compared the efficacy and safety of abacavir with that of zidovudine plus lamivudine and efavirenz in 649 antiretroviral-naive HIV-infected patients. The primary objective was a comparison of proportions of patients achieving plasma HIV-1 RNA levels <or=50 copies/mL through week 48 of the study. RESULTS: At study week 48, 70% of patients in the abacavir group, compared with 69% in the zidovudine group, maintained confirmed plasma HIV-1 RNA levels of <or=50 copies/mL (in the intent-to-treat exposed population). Virologic failure was infrequent (6% in the abacavir group and 4% in the zidovudine group). There was a significant CD4(+) cell response (209 cells/mm(3) in the abacavir group and 155 cells/mm(3) in the zidovudine group). Safety profiles were as expected. CONCLUSION: Abacavir provided an effective and durable antiretroviral response that was noninferior to zidovudine, when combined with lamivudine and efavirenz.
| 5. ||Saag
F; FTC-301A Study Team.|
Efficacy and safety of emtricitabine vs stavudine in combination therapy in antiretroviral-naive patients: a randomized trial. JAMA. 2004 Jul;292(2):180-9
[PubMed ID: 15249567]
CONTEXT: Emtricitabine is a new, once-daily nucleoside reverse transcriptase inhibitor (NRTI) with potent activity against human immunodeficiency virus (HIV). OBJECTIVE: To assess the efficacy and safety of emtricitabine as compared with stavudine when used with a background regimen of didanosine and efavirenz. DESIGN, SETTING, AND PATIENTS: Randomized, double-blind, double-dummy study conducted at 101 research clinics in North America, Latin America, and Europe. The first patient was enrolled on August 21, 2000; no investigator or patient was unblinded until the last patient randomized completed the week 48 visit on October 24, 2002. Analyses were based on data collected in a double-blind setting with a median follow-up of 60 weeks. Patients were 571 antiretroviral-naive, HIV-1-infected adults aged 18 years or older with viral load levels greater than or equal to 5000 copies/mL. INTERVENTIONS: Receipt of either 200 mg of emtricitabine once daily (plus stavudine placebo twice daily) (n = 286) or stavudine at standard doses twice daily (plus emtricitabine placebo once daily) (n = 285) plus open-label didanosine and efavirenz, once daily. MAIN OUTCOME MEASURE: Persistent virological response, defined as achieving and maintaining viral load at or below the limit of assay quantification (< or =400 or 50 copies/mL). RESULTS: At the interim analysis on June 14, 2002, when the last patient randomized completed 24 weeks of double-blind treatment (median follow-up time of 42 weeks), patients in the emtricitabine group had a higher probability of a persistent virological response < or =50 copies/mL vs the stavudine group (85% vs 76%, P =.005). This was associated with a higher mean CD4 cell count change from baseline for the emtricitabine group (156 cells/ microL vs 119 cells/microL, P =.01 [of note, there was no statistical difference at 48 weeks [P =.15], although a sensitivity analysis, using an intent-to-treat population with the last CD4 cell count observation carried forward to week 48 showed a difference [P =.02]]). The independent data and safety monitoring board recommended offering open-label emtricitabine based on the interim analysis. The probability of persistent virological response < or =50 copies/mL through week 60 was 76% for the emtricitabine group vs 54% for the stavudine group (P<.001). The probability of virological failure through week 60 was 4% in the emtricitabine group and 12% in the stavudine group (P<.001). Patients in the stavudine group had a greater probability of an adverse event that led to study drug discontinuation through week 60 than did those in the emtricitabine group (15% vs 7%, P =.005). CONCLUSION: Once-daily emtricitabine appeared to demonstrate greater virological efficacy, durability of response, and tolerability compared with twice-daily stavudine when used with once-daily didanosine and efavirenz.
| 6. ||Gallant
AK; Study 934 Group.|
Tenofovir DF, emtricitabine, and efavirenz vs. zidovudine, lamivudine, and efavirenz for HIV. N Engl J Med. 2006 Jan;354(3):251-60
[PubMed ID: 16421366]
BACKGROUND: Durable suppression of replication of the human immunodeficiency virus (HIV) depends on the use of potent, well-tolerated antiretroviral regimens to which patients can easily adhere. METHODS: We conducted an open-label, noninferiority study involving 517 patients with HIV infection who had not previously received antiretroviral therapy and who were randomly assigned to receive either a regimen of tenofovir disoproxil fumarate (DF), emtricitabine, and efavirenz once daily (tenofovir-emtricitabine group) or a regimen of fixed-dose zidovudine and lamivudine twice daily plus efavirenz once daily (zidovudine-lamivudine group). The primary end point was the proportion of patients without baseline resistance to efavirenz in whom the HIV RNA level was less than 400 copies per milliliter at week 48 of the study. RESULTS: Through week 48, significantly more patients in the tenofovir-emtricitabine group reached and maintained the primary end point of less than 400 copies of HIV RNA per milliliter than did those in the zidovudine-lamivudine group (84 percent vs. 73 percent, respectively; 95 percent confidence interval for the difference, 4 to 19 percent; P=0.002). This difference excludes the inferiority of the tenofovir DF, emtricitabine, and efavirenz regimen, indicating a significantly greater response with this regimen. Significant differences were also seen in the proportion of patients with HIV RNA levels of less than 50 copies per milliliter (80 percent in the tenofovir-emtricitabine group vs. 70 percent in the zidovudine-lamivudine group; 95 percent confidence interval for the difference, 2 to 17 percent; P=0.02) and in increases in CD4 cell counts (190 vs. 158 cells per cubic millimeter, respectively; 95 percent confidence interval for the difference, 9 to 55; P=0.002). More patients in the zidovudine-lamivudine group than in the tenofovir-emtricitabine group had adverse events resulting in discontinuation of the study drugs (9 percent vs. 4 percent, respectively; P=0.02). In none of the patients did the K65R mutation develop. CONCLUSIONS: Through week 48, the combination of tenofovir DF and emtricitabine plus efavirenz fulfilled the criteria for noninferiority to a fixed dose of zidovudine and lamivudine plus efavirenz and proved superior in terms of virologic suppression, CD4 response, and adverse events resulting in discontinuation of the study drugs. (ClinicalTrials.gov number, NCT00112047.)
|8. ||Gulick RM, Ribaudo HJ, Shikuma CM, et al. Three- vs four-drug antiretroviral regimens for the initial treatment of HIV-1 infection: a randomized controlled trial. JAMA. 2006 Aug 16;296(7):769-81. |