Abacavir versus zidovudine combined with lamivudine and efavirenz, for the treatment of antiretroviral-naive HIV-infected adults.
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.


CONCLUSIONS
Abacavir provided an effective and durable antiretroviral response that was noninferior to zidovudine, when combined with lamivudine and efavirenz.
DeJesus
Edwin
E
IDC Research, Altamonte Springs, FL 32701, USA. EdwinDeJesusMD@aol.com
Herrera
Gisela
G
Teofilo
Eugenio
E
Gerstoft
Jan
J
Buendia
Carlos Beltran
CB
Brand
J David
JD
Brothers
Cynthia H
CH
Hernandez
Jaime
J
Castillo
Steve A
SA
Bonny
Tab
T
Lanier
E Randall
ER
Scott
Trevor R
TR
D000293:Adolescent; D000328:Adult; D000368:Aged; D000480:Alkynes; D019380:Anti-HIV Agents / Q000009:adverse effects / Q000627:therapeutic use; D048588:Benzoxazines; D018791:CD4 Lymphocyte Count; D003521:Cyclopropanes; D015224:Dideoxynucleosides / Q000009:adverse effects / Q000627:therapeutic use*; D004311:Double-Blind Method; D004359:Drug Therapy, Combination; D005260:Female; D015658:HIV Infections / Q000188:drug therapy*; D006801:Humans; D019259:Lamivudine / Q000009:adverse effects / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D010078:Oxazines / Q000009:adverse effects / Q000627:therapeutic use*; D012367:RNA, Viral / Q000097:blood; D015215:Zidovudine / Q000009:adverse effects / Q000627:therapeutic use*; D000099227:Abacavir
D000480:Alkynes; D019380:Anti-HIV Agents; D048588:Benzoxazines; D003521:Cyclopropanes; D015224:Dideoxynucleosides; D019259:Lamivudine; D010078:Oxazines; D012367:RNA, Viral; D015215:Zidovudine; D000099227:Abacavir; C098320:efavirenz