Efficacy and Safety Study of Buprenorphine HCl Buccal Film in Subjects With Low Back Pain

This is an enriched enrollment, randomized withdrawal study with an open label,
dose-titration period followed by a randomized, double-blind, placebo-controlled treatment
period of 12 weeks. During the double-blind treatment period, this study will evaluate the
effectiveness of buprenorphine HCl buccal film versus placebo buccal film in treating CLBP
in subjects.

Buprenorphine HCl buccal film is an oral transmucosal form of the opioid analgesic,
buprenorphine hydrochloride, intended for application to the buccal mucosa. Buprenorphine is
a synthetic opioid that is classified as a partial µ-receptor agonist and a Schedule III
controlled substance in the United States.

Inclusion Criteria:

- Male or non-pregnant and non-nursing female aged 18 or older

- History of moderate to severe chronic low back pain for ≥3 months with a pain
intensity ≥5 [11 point numerical rating scale] reported at the open-label titration
period Day 0/1 visit following a washout period (opioids, nonsteroidal
anti-inflammatory drugs [NSAIDs], and muscle relaxants) of approximately 12 to 24
hours

- Currently taking ≤60 mg oral morphine/day or equianalgesic dose of another opioid
(including opioid naïve) for 1 week or longer

- Stable health, as determined by the Investigator, on the basis of medical history,
physical examination, and screening laboratory results so as to comply with all study
procedures

- Female subjects of childbearing potential must be using a recognized effective method
of birth control

- Written informed consent obtained at Screening, prior to any procedure being
performed

Exclusion Criteria:

- Reflex sympathetic dystrophy or causalgia (complex regional pain syndrome), acute
spinal cord compression, cauda equina compression, acute nerve root compression,
meningitis, and discitis

- Surgical procedure for back pain within 2 months prior to screening or nerve/plexus
block within 4 weeks of screening

- Hypokalemia or clinically unstable cardiac disease, including: unstable atrial
fibrillation, symptomatic bradycardia, unstable congestive heart failure, or active
myocardial ischemia

- Corrected QT (QTc) interval of >450 milliseconds on the 12-lead electrocardiogram
(ECG)

- History of long QT syndrome, or an immediate family member with this condition

- Diagnosis of moderate to severe hepatic impairment.

- History of severe emesis with opioids

- Clinically significant sleep apnea