Response to efavirenz-containing regimens in previously antiretroviral-naive HIV-positive patients: the role of gender.
BACKGROUND
We investigated the role of gender on response to efavirenz (EFV)-containing regimens in previously antiretroviral-naive patients.


METHODS
All previously antiretroviral-naive individuals from the Royal Free Hospital in London starting EFV from 1996 onward were included. Treatment failure was defined as the first of 2 consecutive viral load measurements >500 copies/mL more than 24 weeks after starting EFV. Standard survival methods were used to assess time to discontinuation and to treatment failure.


RESULTS
Ninety-six women and 337 men were included. Women were mostly of black African ethnicity (64.6%) with a heterosexual risk (94.8%), whereas men were mostly white (66.8%; P < 0.0001) with a homosexual risk (71.2%; P < 0.0001). Women had lower CD4 counts when starting EFV (median [interquartile range [IQR] = 126 [36, 220] cells/mm for women vs. 190 [109, 268] cells/mm for men; P = 0.0003). After 48 and 96 weeks, 38.8% (95% confidence interval [CI]: 28.8% to 48.7%) and 56.3% (95% CI: 45.8% to 66.9%) of women had discontinued EFV compared with 28.3% (95% CI: 23.4% to 33.2%) and 41.8% (95% CI: 36.3% to 47.3%) of men (P = 0.005). The percentage experiencing failure by 48 and 96 weeks when ignoring treatment changes but censoring at the date of discontinuing all treatment was 1.3% (0.0%, 3.9%) and 4.4% (0.0%, 9.3%) for women compared with 3.8% (1.6%, 6.0%; P = 0.49) and 5.8% (3.0%, 8.6%) for men. Median (IQR) CD4 count increases at 48 weeks were +166 (+89, +239) cells/mm for women and +176 (+93, +263) cells/mm for men.


CONCLUSIONS
Women seem to have comparable virologic and immunologic outcomes to first-line EFV-containing regimens compared with men, although they are more likely to discontinue the drug.
HIV Biostatistics and Epidemiology Group and Department of Primary Care and Population Science, Royal Free and University College Medical School, London, United Kingdom. c.smith@pcps.ucl.ac.uk
Colette J
CJ
Smith
Caroline A
CA
Sabin
Mike S
MS
Youle
Fiona C
FC
Lampe
Sanjay
S
Bhagani
Sara
S
Madge
Dewi
D
Puradiredja
Margaret A
MA
Johnson
Andrew N
AN
Phillips
D000328:Adult; D000480:Alkynes; D019380:Anti-HIV Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D048588:Benzoxazines / Q000008:administration & dosage / Q000627:therapeutic use*; D018791:CD4 Lymphocyte Count; D003521:Cyclopropanes; D005260:Female; D015658:HIV Infections / Q000188:drug therapy*; D006801:Humans; D008297:Male; D012727:Sex Characteristics; D013997:Time Factors; D016896:Treatment Outcome; D019562:Viral Load
D000480:Alkynes; D019380:Anti-HIV Agents; D048588:Benzoxazines; D003521:Cyclopropanes; C098320:efavirenz