Simplification of protease inhibitor-containing regimens with efavirenz, nevirapine or abacavir: safety and efficacy outcomes.
OBJECTIVE
To describe the immunological and virological outcome, and the factors associated to discontinuation in patients switching to a regimen containing efavirenz (EFV), nevirapine (NVP) or abacavir (ABC) after long-term viral suppression under protease inhibitor-including HAART.


METHODS
Observational study at three outpatient clinics for HIV care in Italy.


METHODS
Patients with HIV RNA <80 copies/ml and CD4 >200 cells/ml for at least 6 months on a protease inhibitor-containing treatment who switched to NVP, EFV or ABC were included in the study. End-points were immunological failure, virological failure and discontinuation due to toxicity. Survival analyses were performed to find out any independent variables predictive of reaching the end-points.


RESULTS
177 patients were enrolled; 85 started EFV, 54 NVP and 38 ABC as part of the simplification regimen. 16/159 patients experienced immunological failure: the variables associated to CD4 count decrease were HIV RNA set point value (HR 2.32 for each log10 copies more, P=0.040) and intolerance/toxicity as reason for simplification (HR 3.96, P=0.05). 13/151 subjects showed virological failure; an AIDS diagnosis (HR 6.04, P=0.021) and the use of NVP (HR 7.98, P=0.027) were associated to a worse virological outcome, while patients naive before HAART showed a lower risk of failure (HR 0.008, P=0.007). 16/177 patients discontinued simplification regimen due to toxicity; longer HAART duration before switch was associated to risk reduction (HR 0.92, P=0.004).


CONCLUSIONS
Simplification is safe and effective, but it should be offered to patients with shorter treatment duration, and in good clinical and immunovirological conditions.
Chiesa
Elisabetta
E
Institute of Infectious Diseases and Tropical Medicine, University of Milan, Italy.
Bini
Teresa
T
Adorni
Fulvio
F
Capetti
Amedeo
A
Rizzardini
Giuliano
G
Faggion
Ivano
I
Mussini
Cristina
C
Sollima
Salvatore
S
Melzi
Sara
S
Bongiovanni
Marco
M
Tordato
Federica
F
Cicconi
Paola
P
Castelnuovo
Barbara
B
Rusconi
Stefano
S
d'Arminio Monforte
Antonella
A
D000480:Alkynes; D019380:Anti-HIV Agents / Q000627:therapeutic use*; D023241:Antiretroviral Therapy, Highly Active; D048588:Benzoxazines; D018791:CD4 Lymphocyte Count; D003521:Cyclopropanes; D015224:Dideoxynucleosides / Q000009:adverse effects / Q000627:therapeutic use*; D004334:Drug Administration Schedule; D004359:Drug Therapy, Combination; D015658:HIV Infections / Q000188:drug therapy* / Q000276:immunology / Q000821:virology; D017320:HIV Protease Inhibitors / Q000009:adverse effects / Q000627:therapeutic use*; D015497:HIV-1 / Q000502:physiology; D006801:Humans; D019829:Nevirapine / Q000009:adverse effects / Q000627:therapeutic use*; D010078:Oxazines / Q000009:adverse effects / Q000627:therapeutic use*; D012367:RNA, Viral / Q000097:blood; D012189:Retrospective Studies; D018894:Reverse Transcriptase Inhibitors / Q000009:adverse effects / Q000627:therapeutic use*; D016896:Treatment Outcome; D000099227:Abacavir
D000480:Alkynes; D019380:Anti-HIV Agents; D048588:Benzoxazines; D003521:Cyclopropanes; D015224:Dideoxynucleosides; D017320:HIV Protease Inhibitors; D019829:Nevirapine; D010078:Oxazines; D012367:RNA, Viral; D018894:Reverse Transcriptase Inhibitors; D000099227:Abacavir; C098320:efavirenz