The effects of enfuvirtide therapy on body composition and metabolic parameters over 48 weeks in the TORO body imaging substudy.
OBJECTIVE
The aim of the study was to compare the metabolic and morphological effects of enfuvirtide plus an optimized background (OB) regimen vs. OB alone (control group) in treatment-experienced patients in the T-20 vs. Optimized Regimen Only (TORO) studies.


METHODS
Body composition and metabolic changes were investigated in patients over 48 weeks, based on fasting chemistries, body weight, and other anthropometric measurements. Dual-energy X-ray absorptiometry (DEXA) and computed tomography (CT) scans were performed in a patient subgroup (n=155) at baseline and at weeks 24 and 48.


RESULTS
At week 48, mean changes from baseline were similar between treatment groups for glucose, insulin, C-peptide, total cholesterol, low-density lipoprotein (LDL) cholesterol, very low density lipoprotein (VLDL) cholesterol, high-density lipoprotein (HDL) cholesterol and triglyceride levels. The enfuvirtide group experienced a significant increase in body weight [mean change from baseline +0.99 kg; 95% confidence interval (CI) +0.54, +1.44] and, in those who had body scans, there was a significant increase in truncal fat (by DEXA: median change +419.4 g; 95% CI+71.3, +767.5) and total fat [visceral adipose tissue (VAT)+subcutaneous adipose tissue (SAT) by single-slice abdominal CT scan: median change +25.5 cm(2) ; 95% CI+8.9, +42.0] over 48 weeks; significant increases in these parameters were not seen in the control group. There was no significant change in truncal:peripheral fat ratio in either the enfuvirtide or the control group.


CONCLUSIONS
The addition of enfuvirtide to an OB regimen does not appear to have unfavourable effects on fat distribution or metabolic parameters.
Cooper
D A
DA
National Centre in HIV Epidemiology and Clinical Research, University of New South Wales, Sydney, Australia. dcooper@nchecr.unsw.edu.au
Cordery
D V
DV
Reiss
P
P
Henry
K
K
Nelson
M
M
O'Hearn
M
M
Reynes
J
J
Arastéh
K
K
Chung
J
J
Rowell
L
L
Guimaraes
D
D
Bertasso
A
A
D015502:Absorptiometry, Photon; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D023241:Antiretroviral Therapy, Highly Active / Q000009:adverse effects / Q000379:methods; D001823:Body Composition / Q000187:drug effects*; D001835:Body Weight / Q000187:drug effects; D050171:Dyslipidemias / Q000139:chemically induced* / Q000453:epidemiology; D000077560:Enfuvirtide; D005260:Female; D015700:HIV Envelope Protein gp41 / Q000009:adverse effects* / Q000494:pharmacology; D023581:HIV Fusion Inhibitors / Q000009:adverse effects* / Q000494:pharmacology; D015658:HIV Infections / Q000188:drug therapy* / Q000378:metabolism; D039682:HIV-Associated Lipodystrophy Syndrome / Q000139:chemically induced; D006801:Humans; D008297:Male; D008875:Middle Aged; D010446:Peptide Fragments / Q000009:adverse effects* / Q000494:pharmacology; D014057:Tomography, X-Ray Computed; D055105:Waist Circumference / Q000187:drug effects; D049629:Waist-Hip Ratio; D055815:Young Adult
D015700:HIV Envelope Protein gp41; D023581:HIV Fusion Inhibitors; D010446:Peptide Fragments; D000077560:Enfuvirtide