A Phase 3 Study of Tanezumab for Chronic Low Back Pain

This is a randomized, double blind, placebo and active controlled, multicenter, parallel
group Phase 3 study of the efficacy and safety of tanezumab when administered by SC injection
for up to 56 weeks in subjects with chronic low back pain. Approximately 1800 subjects will
be randomized to 1 of 4 treatment groups in a 2:2:2:3 ratio (ie, 400 subjects per treatment
group for the placebo, tanezumab 5 mg and tanezumab 10 mg treatment groups and 600 subjects
in the tramadol PR treatment group). Treatment groups will include: 1.) Placebo administered
SC at an 8 week interval plus placebo matching tramadol PR up to Week 16. At the Week 16
visit, subjects in this group who meet the efficacy responder criteria will be switched in a
blinded fashion in a 1:1 ratio to either tanezumab 5 mg or tanezumab 10 mg administered SC at
an 8 week interval plus placebo matching tramadol PR to Week 56; 2.)Tanezumab 5 mg SC
administered at an 8 week interval plus placebo matching tramadol PR to Week 56; 3.)
Tanezumab 10 mg SC administered at an 8 week interval plus placebo matching tramadol PR to
Week 56; 4.) Oral tramadol PR plus placebo administered SC at an 8 week interval to Week 56.
The study is designed with a total duration (post randomization) of up to 80 weeks and will
consist of three periods: Screening (up to a maximum of 37 days; includes a Washout Period
and an Initial Pain Assessment Period), a Double blind Treatment Period (comprised of a 16
week Primary Efficacy Phase and a 40 week Long Term Safety and Efficacy Phase), and a Follow
up Period (24 weeks). The Screening Period (beginning up to 37 days prior to Randomization)
includes a Washout Period (lasting 2 32 days), if required, and an Initial Pain Assessment
Period (the 5 days prior to Randomization/Baseline). Prior to entering the study, subjects
must have a documented history of previous inadequate treatment response to medications in 3
different categories of agents commonly used to treat and generally considered effective for
the treatment of chronic low back pain.

Inclusion Criteria:

-Chronic low back pain ≥3 months in duration, Quebec Task Force in Spinal Disorders class 1
or 2, with documented history of previous inadequate treatment response to at least 3
different categories of agents commonly used and generally considered effective for the
treatment of chronic low back pain.

Exclusion Criteria:

--Diagnosis of osteoarthritis of the knee or hip as defined by the American College of
Rheumatology (ACR) criteria.

- Subjects who have Kellgren Lawrence Grade > or =2 radiographic evidence of hip or
Grade > or=3 radiographic evidence of knee osteoarthritis will be excluded;

- History or radiographic evidence of other diseases that could confound efficacy or
safety assessments (e.g., rheumatoid arthritis).

- History or radiographic evidence of orthopedic conditions that may increase the risk
of, or confound assessment of joint safety conditions during the study.

- Signs and symptoms of clinically significant cardiac disease within 6 months of the
study (e.g., unstable angina, myocardial infarction, resting bradycardia, poorly
controlled or untreated hypertension) as defined in the protocol or subjects with any
other cardiovascular illness that in the opinion of the Investigator would render a
subject unsuitable to participate in the study

- History, diagnosis, or signs and symptoms of clinically significant neurological
disease (e.g., transient ischemic attack, stroke, peripheral or autonomic neuropathy)
as specified in the protocol

- Subjects with evidence or symptoms consistent with autonomic dysfunction (e.g.,
orthostatic hypotension and/or autonomic symptoms) as defined in the protocol.