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.
IDC Research, Altamonte Springs, FL 32701, USA. EdwinDeJesusMD@aol.com
Edwin
E
DeJesus
Gisela
G
Herrera
Eugenio
E
Teofilo
Jan
J
Gerstoft
Carlos Beltran
CB
Buendia
J David
JD
Brand
Cynthia H
CH
Brothers
Jaime
J
Hernandez
Steve A
SA
Castillo
Tab
T
Bonny
E Randall
ER
Lanier
Trevor R
TR
Scott
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