Efficacy and safety of atazanavir-based highly active antiretroviral therapy in patients with virologic suppression switched from a stable, boosted or unboosted protease inhibitor treatment regimen: the SWAN Study (AI424-097) 48-week results.
BACKGROUND
Atazanavir is a once-daily protease inhibitor (PI) for the treatment of human immunodeficiency virus (HIV) infection that has previously been studied in cohorts of treatment-naive and treatment-experienced patients. Limited data are available on the usefulness of switching from a PI-based regimen to a regimen based on a different PI, such as atazanavir, in HIV-infected patients experiencing virologic suppression but seeking regimen simplification.


METHODS
The Switch to Another Protease Inhibitor (SWAN) study was a 48-week, open-label trial involving HIV-positive patients with virologic suppression who were receiving stable PI-based regimens (with or without ritonavir). Patients were randomized 2 : 1 to switch to atazanavir (400 mg per day)--or, if they were receiving tenofovir, to atazanavir-ritonavir (300/100 mg per day)--or to continue to receive their existing PI. The proportion of patients who experienced virologic rebound (defined as an HIV RNA load >or=50 copies/mL) was compared through study week 48.


RESULTS
Patients either received an atazanavir-containing regimen (278 patients) or continued to receive a comparator PI-containing regimen (141 patients). The proportion of patients who experienced virologic rebound was significantly lower among those who switched to an atazanavir-containing regimen (19 [7%] of 278) than it was among those who continued to receive a comparator PI regimen (22 [16%] of 141; P=.004). Patients who switched to atazanavir therapy experienced significantly fewer total cholesterol, fasting triglyceride, and non-high density lipoprotein cholesterol elevations than did patients in the comparator PI group (P<.001); patients receiving atazanavir had comparable rates of adverse event-related discontinuation and serious adverse events.


CONCLUSIONS
In patients with virologic suppression who were receiving other PIs, switching to a once-per-day regimen containing atazanavir provided better maintenance of virologic suppression (as demonstrated by significantly lower rates of virologic rebound and treatment failure than those observed with continued unmodified therapy), a comparable safety profile, and improved lipid parameters, compared with those for patients who continued their prior PI-based regimen through 48 weeks.
Gatell
Jose
J
Hospital Clinic-IDIBAPS, University of Barcelona, Barcelona, Spain. gatell0@attglobal.net
Salmon-Ceron
Dominique
D
Lazzarin
Adriano
A
Van Wijngaerden
Eric
E
Antunes
Francisco
F
Leen
Clifford
C
Horban
Andrzej
A
Wirtz
Victoria
V
Odeshoo
Linda
L
Van den Dungen
Monique
M
Gruber
Claudia
C
Ledesma
Emilio
E
D000293:Adolescent; D000328:Adult; D000368:Aged; D023241:Antiretroviral Therapy, Highly Active / Q000009:adverse effects; D000069446:Atazanavir Sulfate; D004334:Drug Administration Schedule; D005260:Female; D015658:HIV Infections / Q000188:drug therapy* / Q000821:virology; D017320:HIV Protease Inhibitors / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009842:Oligopeptides / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D011725:Pyridines / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D016896:Treatment Outcome; D019562:Viral Load
D017320:HIV Protease Inhibitors; D009842:Oligopeptides; D011725:Pyridines; D000069446:Atazanavir Sulfate