Abacavir/lamivudine/zidovudine maintenance after standard induction in antiretroviral therapy-naïve patients: FREE randomized trial interim results. A randomized trial of simplified maintenance therapy with abacavir, lamivudine, and zidovudine in human immunodeficiency virus infection. Impact of an educational program on efficacy and adherence with a twice-daily lamivudine/zidovudine/abacavir regimen in underrepresented HIV-infected patients. Triple-nucleoside regimens versus efavirenz-containing regimens for the initial treatment of HIV-1 infection. A prospective, 96-week study of the impact of Trizivir, Combivir/nelfinavir, and lamivudine/stavudine/nelfinavir on lipids, metabolic parameters and efficacy in antiretroviral-naive patients: effect of sex and ethnicity. Maintenance antiretroviral therapies in HIV infected patients with undetectable plasma HIV RNA after triple-drug therapy. AIDS Clinical Trials Group Study 343 Team. Comparison of sequential three-drug regimens as initial therapy for HIV-1 infection. High rate of early virological failure with the once-daily tenofovir/lamivudine/nevirapine combination in naive HIV-1-infected patients. Efficacy of three short-course regimens of zidovudine and lamivudine in preventing early and late transmission of HIV-1 from mother to child in Tanzania, South Africa, and Uganda (Petra study): a randomised, double-blind, placebo-controlled trial.
Maintenance with a triple nucleoside reverse transcriptase Inhibitor (NRTI) regimen after successful induction with a dual NRTI/protease inhibitor (PI) combination may be advantageous, because of low pill burden, favorable lipids, and less drug interactions. This strategy to become free of PI-related problems without losing viral efficacy has not been formally tested. We performed a randomized, open-label, multicenter, 96-week comparative study in antiretroviral therapy (ART)-naïve patients with CD4 <or=350 cells/mm(3) and HIV-1 RNA concentrations (viral load [VL]) greater than 30,000 copies per milliliter. Patients were randomized after reaching VL less than 50 copies per milliliter on two consecutive occasions between 12 and 24 weeks after start of zidovudine/lamuvidine and lopinavir/ritonavir combination. Eligible subjects switched to abacavir/lamivudine/zidovudine (TZV) or continued the PI-containing regimen. Here we present the 48-week data with virologic success rate (failure: VL > 50 copies per milliliter). Two hundred seven patients had similar baseline (BL) characteristics: median CD4 180 cells/mm(3), median VL 5.19 log(10) copies per milliliter. One hundred twenty subjects (58%) met randomization criteria. Baseline VL differed significantly between dropouts and randomized subjects (median 5.41 versus 5.06 log(10) copies per milliliter, p = 0.017), as did CD4 cells (median 160 and 200 cells/mm(3), p = 0.044). Sixty-one subjects received TZV and 59 subjects continued NRTIs/PI. At week 48, 2 patients in the TZV group and 5 in the PI group did not have a sustained virologic suppression (log rank test; p = 0.379). CD4 counts increased significantly in both arms. In ART-naïve patients, TZV maintenance had similar antiviral efficacy compared to continued standard ART at 48 weeks after baseline. Patients on successful standard ART can be safely switched to a NRTI-only regimen, at least for the tested time period. This randomized study evaluated the efficacy and tolerability of continued treatment with protease inhibitor plus nucleoside-analogue combination regimens (n=79) or a change to the simplified regimen of abacavir-lamivudine-zidovudine (n=84) in patients with suppressed human immunodeficiency virus type 1 (HIV-1) RNA for > or = 6 months who did not have the reverse transcriptase 215 mutation. After a median follow-up of 84 weeks, virologic failure was 6% in the continuation and 15% in the simplified group (P=.081). Previous zidovudine monotherapy or dual therapy and archived reverse transcriptase resistance mutations in HIV-1 DNA at baseline were significant predictors of failure. Study treatment was discontinued because of adverse events in 20% of the continuation and 7% of the simplified group (P=.021). Simplification to abacavir-lamivudine-zidovudine significantly decreased nonfasting cholesterol and triglyceride levels; however, this switch strategy carries a risk of virologic failure when treatment history or resistance testing suggest the presence of archived resistance mutations to the simplified regimen. A 24-week open-label clinical trial was conducted in 195 HIV-infected adults commonly underrepresented in research (35% female, 71% African American, 21% Hispanic, and 20% injection drug users [IDUs]) to evaluate the effect of an HIV educational program on efficacy and adherence with a simple, compact, twice-daily triple nucleoside regimen containing a lamivudine (150 mg)/zidovudine (300 mg) combination (COM) tablet plus abacavir (ABC), 300 mg. At baseline, the patients' median plasma HIV-1 RNA level was 4.18 log10 copies/mL and the median CD4+ cell count was 379 cells/mm3. Patients were randomized 1:1 to 4 modules of the Tools for Health and Empowerment HIV education intervention plus routine counseling (EI + RC; n = 96) or to routine counseling alone (RC; n = 99). No differences between the EI + RC and RC treatment arms were observed with respect to the proportion of patients achieving plasma HIV-1 RNA levels <40 copies/mL (60% [33/55] vs. 55% [38/69]; P = 0.529) or <400 copies/mL (80% [44/55] vs. 80% [55/69]; P = 0.689) at week 24 (intent-to-treat observed analysis), increase in median CD4 cell count above baseline at week 24 (78.3 vs. 104.8 cells/mm3; P = 0.498), or mean overall adherence rates as measured by the Medication Event Monitoring System (MEMS) (70% vs. 74%). COM + ABC was generally well tolerated, and no association was observed between interruptions in treatment and the development of ABC hypersensitivity (5 suspected cases). In conclusion, in underrepresented patients, the EI used in this study did not affect the efficacy and adherence results with ABC + COM to any greater degree than did RC. Regimens containing three nucleoside reverse-transcriptase inhibitors offer an alternative to regimens containing nonnucleoside reverse-transcriptase inhibitors or protease inhibitors for the initial treatment of human immunodeficiency virus type 1 (HIV-1) infection, but data from direct comparisons are limited.
                This randomized, double-blind study involved three antiretroviral regimens for the initial treatment of subjects infected with HIV-1: zidovudine-lamivudine-abacavir, zidovudine-lamivudine plus efavirenz, and zidovudine-lamivudine-abacavir plus efavirenz.
                We enrolled a total of 1147 subjects with a mean baseline HIV-1 RNA level of 4.85 log10 (71,434) copies per milliliter and a mean CD4 cell count of 238 per cubic millimeter were enrolled. A scheduled review by the data and safety monitoring board with the use of prespecified stopping boundaries led to a recommendation to stop the triple-nucleoside group and to present the results in the triple-nucleoside group in comparison with pooled data from the efavirenz groups. After a median follow-up of 32 weeks, 82 of 382 subjects in the triple-nucleoside group (21 percent) and 85 of 765 of those in the combined efavirenz groups (11 percent) had virologic failure; the time to virologic failure was significantly shorter in the triple-nucleoside group (P<0.001). This difference was observed regardless of the pretreatment HIV-1 RNA stratum (at least 100,000 copies per milliliter or below this level; P< or =0.001 for both comparisons). Changes in the CD4 cell count and the incidence of grade 3 or grade 4 adverse events did not differ significantly between the groups.
                In this trial of the initial treatment of HIV-1 infection, the triple-nucleoside combination of abacavir, zidovudine, and lamivudine was virologically inferior to a regimen containing efavirenz and two or three nucleosides.
                Copyright 2004 Massachusetts Medical Society To compare the lipid and metabolic effects, efficacy, and safety of twice-daily regimens of Trizivir (abacavir 300 mg/lamivudine 150 mg/zidovudine 300 mg triple nucleoside tablet; TZV), Combivir (lamivudine 150 mg/zidovudine 300 mg combination tablet; COM)+nelfinavir (NFV), and stavudine (d4 T)+lamivudine (3TC)+NFV.
                An international, phase 4, open-label, parallel-group, 34-centre study was conducted in 254 non-diabetic, antiretroviral-naive, HIV-infected out-patients with an HIV-1 RNA level of >1000 HIV-1 RNA copies/mL and < or =200,000 copies/mL and a CD4 cell count of >50 cells/microL.
                Patients were randomized 1 : 1 : 1 to TZV twice daily (n = 85), COM/NFV 1250 mg twice daily (n = 88), or d4T 40 mg+3TC 150 mg+NFV 1250 mg twice daily (n = 81) for 96 weeks. Treatments were compared using analysis of covariance (ANCOVA) with regard to changes from baseline in fasting lipids in the total population and in sex and ethnic subgroups. The proportions of patients achieving HIV-1 RNA <50 and <400 copies/mL were compared using a 95% confidence interval (CI) on the difference between proportions.
                The study population was diverse (50% female, 40% black and 37% Hispanic). Mean baseline low-density lipoprotein (LDL) cholesterol was 99 mg/dL, HIV-1 RNA was 4.43 log10 copies/mL and CD4 cell count was 355 cells/microL. At week 96, fasting LDL cholesterol changed minimally in the TZV group [least square mean (LSM) change from baseline, -8 mg/dL], but increased with d4T/3TC/NFV and COM/NFV (+29 and +19 mg/dL, respectively; P < 0.001 versus TZV). Week 96 LDL-cholesterol levels were significantly lower in the TZV group than in the other two treatment groups in women and men and lower than in the d4T/3TC/NFV group in Hispanic and black patients. In black patients, the week-96 LSM change from baseline in LDL cholesterol was significantly less with TZV than with d4T/3TC/NFV (+1 vs+39 mg/dL; P = 0.003). Total cholesterol >200 mg/dL occurred in a smaller proportion of patients receiving TZV (30%) compared with COM/NFV (50%) or d4T/3TC/NFV (60%; P = 0.005 vs TZV). High-density lipoprotein (HDL) cholesterol did not change markedly with any treatment. Although triglycerides increased, they changed least in women and Hispanic patients receiving TZV. Virological and CD4 responses to the treatments were similar in the total population and in the subgroups. Diarrhoea was reported more often in the NFV arms and nausea in the ZDV arms.
                Over 96 weeks, TZV twice daily has significantly less effect on LDL cholesterol than COM/NFV or d4T/3TC/NFV twice daily, especially in women and black patients, and is associated with similar virological and CD4 responses. Combination antiretroviral therapy with indinavir, zidovudine, and lamivudine can suppress the level of human immunodeficiency virus (HIV) RNA in plasma below the threshold of detection for two years or more. We investigated whether a less intensive maintenance regimen could sustain viral suppression after an initial response to combination therapy.
                HIV-infected subjects who had CD4 cell counts greater than 200 per cubic millimeter, who had been treated with indinavir, lamivudine, and zidovudine, and who had less than 200 copies of HIV RNA per milliliter of plasma after 16, 20, and 24 weeks of induction therapy were randomly assigned to receive either continued triple-drug therapy (106 subjects), indinavir alone (103 subjects), or a combination of zidovudine and lamivudine (107 subjects). The primary end point was loss of viral suppression, which was defined as a plasma level of at least 200 copies of HIV RNA per milliliter on two consecutive measurements during maintenance therapy.
                During maintenance treatment, 23 percent of the subjects receiving indinavir and 23 percent of those receiving zidovudine and lamivudine, but only 4 percent of those receiving all three drugs, had loss of viral suppression (P<0.001 for the comparison between triple-drug therapy and the other two maintenance regimens). Subjects with greater increases in CD4 cell counts during induction therapy, higher viral loads at base line (i.e., at the beginning of induction therapy), and slower rates of viral clearance were at greater risk for loss of viral suppression. The presence of zidovudine-resistance mutations in HIV RNA at base line was strongly predictive of the loss of viral suppression in subjects treated with zidovudine and lamivudine.
                The suppression of plasma HIV RNA after six months of treatment with indinavir, zidovudine, and lamivudine is better sustained by the continuation of these three drugs than by maintenance therapy with either indinavir alone or zidovudine and lamivudine. 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.
                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.
                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.
                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.
                Copyright 2003 Massachusetts Medical Society The combination of one non-nucleoside reverse transcriptase inhibitor (NNRTI) with two nucleoside reverse transcriptase inhibitors is a validated first-line antiretroviral (ARV) therapy. The once-daily combination of lamivudine, tenofovirDF and nevirapine has not been evaluated in a clinical trial.
                Randomized, open-label, multicentre, non-inferiority trial comparing lamivudine, tenofovirDF and nevirapine once daily (Group 2) with zidovudine/lamivudine and nevirapine twice daily (Group 1), in naive HIV-1-infected patients with a CD4 count <350/mm(3). We planned to enroll 250 patients.
                As of May 2006, 71 patients had been enrolled (35 in Group 1 and 36 in Group 2) and an unplanned interim analysis was done. The groups were comparable at baseline: median CD4 count was 195 and 191/mm(3) and median plasma viral load was 4.9 log(10) and 5.01 log(10), respectively, in Groups 1 and 2. Eight early non-responses (22.2%) were observed, all in Group 2, while two later viral rebounds occurred. Resistance genotypes for the nine Group 2 failing patients showed the mutations M184V/I (n = 3), K65R (n = 6), one or more NNRTI resistance mutations in all cases. At baseline, the nine Group 2 patients who failed had higher median plasma viral load (5.4 log(10)) and lower median CD4 count (110/mm(3)) than the other Group 2 patients (4.7 log(10), P = 0.002 and 223/mm(3), P = 0.004). Nevirapine trough concentrations were not different between the two groups, nor between patients with full viral suppression or those who failed in Group 2. Due to slow recruitment, and those results, the steering committee decided to stop the trial at 12 months.
                In ARV-naive HIV-1-infected patients, the once-daily lamivudine, tenofovirDF and nevirapine regimen resulted in a high rate of early virological failures. The reasons for the failures remain unclear. Large reductions in transmission of HIV-1 from mother to child have been achieved in more-developed countries due to the use of antiretrovirals. Short-course regimens, suitable for resource-poor countries, have also been shown to significantly reduce peripartum HIV-1 transmission. We assessed the efficacy of short-course regimens with zidovudine and lamivudine in a predominantly breastfeeding population.
                We did a randomised, double-blind, placebo-controlled trial in South Africa, Uganda, and Tanzania. Between June, 1996, and January, 2000, HIV-1-infected mothers were randomised to one of four regimens: A, zidovudine plus lamivudine starting at 36 weeks' gestation, followed by oral intrapartum dosing and by 7 days' postpartum dosing of mothers and infants; B, as regimen A, but without the prepartum component; C, intrapartum zidovudine and lamivudine only; or placebo. From Feb 18, 1998, onward, women were only randomised to one of the active treatment groups. Primary outcomes were HIV-1 infection and child mortality at week 6 and month 18 after birth. Analysis was by intention to treat of those randomised before Feb 18, 1998.
                1797 HIV-1-infected women were identified. Week 6 HIV-1 transmission rates were 5.7% for group A, 8.9% for group B, 14.2% for group C, and 15.3% for the placebo group. Respective relative risks for HIV-1 transmission in the treatment groups compared with placebo were 0.37 (95% CI 0.21-0.65), 0.58 (0.36-0.94), and 0.93 (0.62-1.40). For the combined endpoint of HIV-1 infection and infant mortality at week 6 rates were 7.0%, 11.6%, 17.5%, and 18.1%, respectively, with relative risks of 0.39 (0.24-0.64), 0.64 (0.42-0.97), and 0.97 (0.68-1.38). 1081 (74%) of the women analysed initiated breastfeeding. Based on an interval-censored survival analysis, HIV-1 infection rates at month 18 were 15% (95% CI 9-23), 18% (12-26), 20% (13-30) and 22% (16-30), respectively.
                Although at week 6 after birth, regimens A and B were effective in reducing HIV-1 transmission, benefits have diminished considerably after 18 months of follow-up. Introduction of short-course regimens to prevent mother-to-child transmission of HIV-1 in less-developed countries should be accompanied by interventions to minimise the risk of subsequent transmission via breastfeeding.
This review provides evidence that co-formulated abacavir-lamivudine-zidovudine remains a viable option for initiating antiretroviral therapy, especially in HIV-infected patients with pre-existing hyperlipidaemia. The varied geographical locations of the included trials augment the external validity of these findings. We are moderately confident in our estimate of the treatment effects of the triple NRTI regimen as initial therapy for HIV infection. In the context of the GRADE approach, such moderate quality of evidence implies that the true effects of the regimen are likely to be close to the estimate of effects found in this review; but there is a possibility that they could be substantially different.  Further research should be geared towards defining the subgroup of HIV patients for whom this regimen will be most beneficial.