Efficacy and tolerability of long-term efavirenz plus nucleoside reverse transcriptase inhibitors for HIV-1 infection.

OBJECTIVE: To compare the long-term efficacy and tolerability of two efavirenz-containing regimens with those of an indinavir-containing regimen in the initial use of HAART. METHOD: HIV-1-infected patients (N = 1266) were randomly assigned to receive one of three regimens: efavirenz, zidovudine plus lamivudine, n = 422; efavirenz plus indinavir, n = 429; or indinavir, zidovudine plus lamivudine, n = 415. Entrance criteria included baseline viral load greater than 10 000 copies/ml HIV-1 RNA, CD4 cell count 50 cells/mul or greater, and no previous use of lamivudine, any non-nucleoside reverse-transcriptase inhibitor or protease inhibitor. The primary endpoint was the proportion of patients (response rate) in each regimen with a viral load under 400 copies/ml at 168 weeks of treatment. RESULTS: Response rates at 168 weeks were 30% in the indinavir, zidovudine, lamivudine group, 48% in the efavirenz, zidovudine, lamivudine group (P < 0.0001, difference estimate; 97.5% confidence interval (CI) 18.5; 10.9, 26), and 40% in the efavirenz plus indinavir group (P = 0.0018, difference estimate; 97.5% CI 10.2; 2.9, 17.6). Median CD4 cell counts increased above respective baselines by 292 cells/mul (efavirenz, zidovudine, lamivudine and indinavir, zidovudine, lamivudine) and 300 cells/mul (efavirenz plus indinavir). Total discontinuations were 54% (efavirenz, zidovudine, lamivudine), 63% (efavirenz plus indinavir), and 69% (indinavir, zidovudine, lamivudine) of which 13, 12 and 26%, respectively, were caused by adverse events. No new or unexpected increases in the rates or severity of adverse events occurred from long-term treatment with efavirenz-containing regimens. CONCLUSION: Long-term HIV therapy with efavirenz-containing regimens, particularly efavirenz, zidovudine, lamivudine, provides significantly greater antiviral activity and tolerability than a regimen of indinavir, zidovudine plus lamivudine.

Dual vs single protease inhibitor therapy following antiretroviral treatment failure: a randomized trial.

CONTEXT: Management of antiretroviral treatment failure in patients receiving protease inhibitor (PI)-containing regimens is a therapeutic challenge. OBJECTIVE: To assess whether adding a second PI improves antiviral efficacy of a 4-drug combination in patients with virologic failure while taking a PI-containing regimen. DESIGN: Multicenter, randomized, 4-arm trial, double-blind and placebo-controlled for second PI, conducted between October 1998 and April 2000, for which there was a 24-week primary analysis with extension to 48 weeks. SETTING: Thirty-one participating AIDS (acquired immunodeficiency syndrome) Clinical Trials Units in the United States. PARTICIPANTS: A total of 481 human immunodeficiency virus (HIV)-infected persons with prior exposure to a maximum of 3 PIs and viral load above 1000 copies/mL. INTERVENTION: Selectively randomized assignment (per prior PI exposure) to saquinavir (n = 116); indinavir (n = 69); nelfinavir (n = 139); or placebo twice per day (n = 157); in combination with amprenavir, abacavir, efavirenz, and adefovir dipivoxil. MAIN OUTCOME MEASURES: Primary efficacy analysis involved the proportion with viral load below 200 copies/mL at 24 weeks. Other measures were changes in viral load and CD4 cell count from baseline, adverse events, and HIV drug susceptibility. RESULTS: Of 481 patients, 148 (31%) had a viral load below 200 copies/mL at week 24. The proportions of patients with a viral load below 200 copies/mL in the saquinavir, indinavir, nelfinavir, and placebo arms were 34% (40/116), 36% (25/69), 34% (47/139), and 23% (36/157), respectively. The proportion in the combined dual-PI arms was higher than in the amprenavir-plus-placebo arm (35% [112/324] vs 23% [36/157], respectively; P =.002). Overall, a higher proportion of nonnucleoside reverse transcriptase inhibitor (NNRTI)-naive patients had a viral load below 200 copies/mL compared with NNRTI-experienced patients (43% [115/270] vs 16% [33/211], respectively; P<.001). Baseline HIV-1 hypersusceptibility to efavirenz (< or = 0.4-fold difference in susceptibility compared with reference virus) was associated with suppression of viral load at 24 weeks to below 200 copies/mL (odds ratio [OR], 3.49; 95% confidence interval [CI], 1.62-7.33; P =.001), and more than 10-fold reduction in efavirenz susceptibility, with less likelihood of suppression at 24 weeks (OR, 0.28; 95% CI, 0.09-0.87; P =.03). CONCLUSIONS: In this study of antiretroviral-experienced patients with advanced immunodeficiency, viral load suppression to below 200 copies/mL was achieved in 31% of patients with regimens containing 4 or 5 new drugs. Use of 2 PIs, being naive to NNRTIs, and baseline hypersusceptibility to efavirenz were associated with a favorable outcome.