Trial Information

Screening visit 1:

Fifty six patients will be randomized to receive etanercept or identical placebo. During the
screening visit, after informed consent is obtained, subjects will undergo a medical history
and physical exam, which will include vital signs, weight, abdominal girth measurements and
an evaluation for signs of underlying infection. A purified protein derivative (PPD) of 5
tuberculin units (TU) (0.1 milliliter of 5 TU/0.1 ml solution) will be intradermally placed
to test for the presence of tuberculosis (TB). Fasting blood work will include a complete
blood count (CBC), glucose, insulin, a cholesterol panel, and urine pregnancy test. Subjects
will be shown what a subcutaneous injection entails using placebo. Patients will be selected
based on their laboratory results, abdominal girth measurements and PPD negativity 48 hrs
after placement.

Screening visit 2:

Subjects will return 48 hours after their first screening visit for evaluation of their PPD
test. In the event of a positive PPD, subjects will be excluded from the study, and their
primary care physicians will be notified of their test result.

Day 1 visit:

Subjects will report to Massachusetts General Hospital (MGH) or Massachusetts Institute of
Technology (MIT) Clinical Research Center (GCRC) after an overnight fast. Fasting blood work
will be obtained to test for CRP, adiponectin, IL-6, TNF-alpha, TNF-alpha receptor 1,
TNF-alpha receptor 2, free fatty acids, glucose, insulin and a cholesterol panel, and CBC. A
urine pregnancy test will be done. Patients will be asked to recall the food they consumed
over the past 24 hours. A bionutritionist will measure height, weight, waist, hip, chest,
arm, neck and thigh circumference. Subjects will be instructed to practice adequate birth
control throughout the study. Serum will be stored for etanercept antibody testing.

Subjects will then undergo an insulin modified frequently sampled intravenous (IV) glucose
tolerance test (FSIGT) as initially developed by Bergman et al.

Dual energy x-ray absorptiometry (DEXA) (Hologic QDR 4500) will be used to determine whole
body and regional fat. The technique has a precision error (1 SD) of 3% for whole body fat
and 1.5% for lean mass. Subjects will also undergo a single thin-slice CT scan of the
abdomen at L4 vertebral body to determine visceral and subcutaneous fat area.

Indirect calorimetry for the measurement of resting energy expenditure indirect calorimetry
using the Deltatrac instrument (Sensormedics, Anaheim, CA) will be carried out.

Drug administration:

Patients will be given a total of either etanercept 50 mg subcutaneously or placebo
subcutaneously at the GCRC at the end of their visit. They will receive this in two
injections of 25 mg each, one given immediately following the other, at different body
sites. Etanercept will be supplied as a sterile, white, preservative-free, lyophilized
powder. The pharmacy will reconstitute it with 1 mL of the supplied sterile bacteriostatic
water for injection (BWFI), USP (containing 0.9% benzyl alcohol). Each vial of etanercept
contains 25 mg etanercept, 40 mg mannitol, 10 mg sucrose, and 1.2 mg tromethamine. Subjects
will receive the 50 mg dose of etanercept or placebo once a week, given as two 25 mg
injections, one immediately following the other, at different body sites, at each of their
ensuing three visits to the GCRC, on Visit Day 8, Visit Day 15 and Visit Day 22. Subjects
will be monitored for 30 minutes after the injection of study drug at each visit. The skin
injection site will be observed and their vital signs will be taken. If a subject has a
significant exposure to varicella virus during the study, transient termination of the study
will be considered.

Day 8 visit, Day 15 visit, Day 22 visit:

Subjects will report to MGH or MIT Clinical Research Center after an overnight fast. Each
subject will undergo a history and physical exam to assess for safety and compliance.
Fasting blood work will be obtained. A bionutritionist will measure subjects' height,
weight, hip and waist circumference and calculate a waist to hip ratio. They will receive 50
mg of either etanercept or placebo, given as two 25 mg doses subcutaneously, at different
body sites.

Day 25 visit:

Subjects will report to MGH or MIT Clinical Research Center after an overnight fast. Each
subject will undergo a history and physical exam to assess for safety and compliance. Blood
work, a urine pregnancy test and 24 hour food recall will be collected, identical to that on
Day 1 visit. Anthropomorphic measurements will be the same as the Day 1 visit. Subjects will
undergo an intravenous glucose tolerance test (IVGTT) identical to that on the Day 1 visit.
Subjects will undergo a DEXA, bioelectric impedance analysis (BIA), and CT, and indirect
calorimetry identical to those on the Day 1 visit. No study drug will be administered at
this visit.