Evaluation of sex differences of fosamprenavir (with and without ritonavir) in HIV-infected men and women.
OBJECTIVE
Recent studies focusing on HIV-1-infected women have suggested the existence of sex-related differences in natural history, antiretroviral pharmacokinetics, efficacy, and tolerability. This article analyzes three pivotal trials of the protease inhibitor (PI) fosamprenavir (FPV) with a view to providing a better understanding of potential sex differences in efficacy and safety.


METHODS
A post hoc, descriptive analysis was performed on data from 700 subjects (26% women) in three trials of FPV to evaluate sex differences with regard to efficacy, rates of discontinuation, and treatment-related adverse events.


RESULTS
No major sex differences were found. Men and women had similarly good antiviral responses, with greater than 60% of treatment-naïve subjects achieving virologic suppression (<400 copies/mL) at 48 weeks. PI-experienced women in CONTEXT receiving once-daily FPV/r experienced the highest rates of discontinuations due to virologic failure (29% in women vs. 8% in men). Women generally had slightly lower rates of liver enzyme elevations and fewer abnormalities of total cholesterol and triglycerides.


CONCLUSIONS
The absence of major sex differences provides reassurance, but the small number of women in these trials limited the ability to draw conclusions. Future trials should be specifically powered to detect sex differences in safety and efficacy.
Division of Infectious Diseases and Center for Clinical AIDS Research Education, David Geffen School of Medicine at UCLA, Los Angeles, California 90095, USA. rhoffman@mednet.ucla.edu
Risa M
RM
Hoffman
Obiamiwe C
OC
Umeh
Cindy
C
Garris
Naomi
N
Givens
Judith S
JS
Currier
D000328:Adult; D000368:Aged; D019380:Anti-HIV Agents / Q000627:therapeutic use*; D002219:Carbamates / Q000009:adverse effects* / Q000627:therapeutic use*; D002784:Cholesterol / Q000097:blood; D005260:Female; D005663:Furans; D015658:HIV Infections / Q000188:drug therapy*; D006801:Humans; D008111:Liver Function Tests; D008297:Male; D008875:Middle Aged; D010755:Organophosphates / Q000009:adverse effects* / Q000627:therapeutic use*; D019438:Ritonavir / Q000627:therapeutic use*; D012737:Sex Factors; D013449:Sulfonamides / Q000009:adverse effects* / Q000627:therapeutic use*; D016896:Treatment Outcome; D014280:Triglycerides / Q000097:blood; D019562:Viral Load
D019380:Anti-HIV Agents; D002219:Carbamates; D005663:Furans; D010755:Organophosphates; D013449:Sulfonamides; D014280:Triglycerides; D002784:Cholesterol; D019438:Ritonavir; C426859:fosamprenavir