Similar antiviral efficacy and tolerability between efavirenz and lopinavir/ritonavir, administered with abacavir/lamivudine (Kivexa), in antiretroviral-naïve patients: a 48-week, multicentre, randomized study (Lake Study).
BACKGROUND
Although efavirenz and lopinavir/ritonavir(r) are both recommended antiretroviral agents in antiretroviral-naïve HIV-infected patients, there are few randomized comparisons of their efficacy and tolerability.


METHODS
A multicenter and randomized study was performed including 126 antiretroviral-naïve patients, randomly assigned to efavirenz+Kivexa (n=63) or lopinavir/r+Kivexa (n=63). Efficacy endpoints were the percentage of patients with HIV-RNA < or =50 copies/mL at week 48 and CD4 recovery. Safety was assessed by comparing toxicity and discontinuations. Statistical analyses were performed on an intention-to-treat (ITT) basis (Missing=Failure).


RESULTS
At week 48, 56.7% of patients in the efavirenz and 63.2% in the lopinavir/r groups showed HIV-1 RNA <50 copies/mL (P=0.770) (intention-to-treat analysis; Missing=Failure). Only 1 (1.53%) patient from each group experienced virological failure. CD4 values increased in both groups (298 cells in the efavirenz group, P=0.001; 249 cells in the lopinavir/r group, P=0.002; P=0.126 between groups). HDL-cholesterol only increased in the efavirenz group (from 39+/-12 mg/dL to 49+/-11; P=0.001). Discontinuations were more frequent in the lopinavir/r group (36.5% versus 28.5%; P=0.193), but more patients with efavirenz interrupted due to toxicity (11.1% versus 6.3%); most of them were attributed to hypersensitivity reaction.


CONCLUSIONS
Similar virological efficacy was observed for efavirenz and lopinavir/r, when administered with Kivexa in antiretroviral-naïve patients, while immunological improvement was slightly superior for efavirenz. The higher rate of discontinuation due to toxicity in the efavirenz group was related to a higher incidence of hypersensitivity reaction. Nowadays, the use of the new formulation of lopinavir/r and the HLA-B*5701 genotype test before starting abacavir should improve the safety profiles of these regimens.
Echeverría
P
P
Fundació Lluita contra SIDA, Hospital Universitari Germans Trias i Pujol, Ctra de Canyet, s/n, 08916 Badalona, Barcelona, Spain. pecheverria@flsida.org
Negredo
E
E
Carosi
G
G
Gálvez
J
J
Gómez
J L
JL
Ocampo
A
A
Portilla
J
J
Prieto
A
A
López
J C
JC
Rubio
R
R
Mariño
A
A
Pedrol
E
E
Viladés
C
C
del Arco
A
A
Moreno
A
A
Bravo
I
I
López-Blazquez
R
R
Pérez-Alvarez
N
N
Clotet
B
B
D000328:Adult; D000480:Alkynes; D019380:Anti-HIV Agents / Q000009:adverse effects / Q000627:therapeutic use*; D048588:Benzoxazines / Q000009:adverse effects / Q000627:therapeutic use*; D018791:CD4 Lymphocyte Count; D003521:Cyclopropanes; D015224:Dideoxynucleosides; D004338:Drug Combinations; D004342:Drug Hypersensitivity; D005260:Female; D015658:HIV Infections / Q000188:drug therapy*; D006801:Humans; D019259:Lamivudine / Q000009:adverse effects; D061466:Lopinavir; D008297:Male; D008875:Middle Aged; D011744:Pyrimidinones / Q000009:adverse effects / Q000627:therapeutic use*; D012367:RNA, Viral / Q000097:blood; D019438:Ritonavir / Q000009:adverse effects / Q000627:therapeutic use*; D016896:Treatment Outcome; D019562:Viral Load; D028761:Withholding Treatment / Q000706:statistics & numerical data; D000099227:Abacavir
D000480:Alkynes; D019380:Anti-HIV Agents; D048588:Benzoxazines; D003521:Cyclopropanes; D015224:Dideoxynucleosides; D004338:Drug Combinations; D019259:Lamivudine; D061466:Lopinavir; D011744:Pyrimidinones; D012367:RNA, Viral; D019438:Ritonavir; C492871:abacavir, lamivudine drug combination; D000099227:Abacavir; C098320:efavirenz