A Study To Monitor Long-Term Treatment With PF-00547659

The rationale for conducting this open-label extension (OLE) study is primarily to evaluate
long term safety of PF 00547659. This protocol also provides the opportunity for continued
treatment for subjects responding to treatment from the feeder study. It also provides an
opportunity for initial treatment for subjects randomized to placebo in the feeder study.
This is a multi center Phase 2, open label, safety extension study for feeder studies which
evaluate PF 00546759 in subjects with moderate to severe Crohn's disease. Subjects eligible
for this study will have completed the 12 week double blind induction period in study
A7281006 and will be stratified by responders or non responders based on change in CDAI in
that study, without unblinding treatment assignment from study A7281006. Additionally,
subjects who have completed study A7281008 with a clinical response, as defined by that
protocol, will also be eligible for this study and treated as "responders". All subjects
entering this study must have discontinued immunosuppressant therapy.

Subjects entering this study will be given a 75 mg SC dose at baseline and then every 4
weeks through Week 72. After the active treatment period, the subjects will enter a 24 month
follow up period including 6 monthly visits followed by 18 month extended contact (every 6
month telephone contacts). At Week 96, subjects will undergo an End of Study visit but will
continue the every 6 month telephone contacts until Week 168.

Inclusion Criteria:

- Subjects between 18 and 76 years of age.

- Subjects previously enrolled in study A7281006 who have completed the blinded 84 day
(12 week) induction period or in study A7281008 who have completed Week 12 and have
demonstrated a clinical response as defined by that protocol.

Exclusion Criteria:

- Subjects that have completed Day 84 (Week 12) of a PF-00547659 study but have
experienced serious event(s) related to the investigational product, an unstable
medical condition, or any other reason, in the opinion of the investigator, would
hinder entry or participation in this study.

- Subjects who are taking any dose of azathioprine, 6-mercaptopurine or methotrexate.