Patients with unilateral or bilateral osteoarthritis (OA) of the knee participated in a Phase II clinical trial to assess the efficacy of lidocaine 5% patch compared with placebo in the treatment of pain from OA of the knee.

Key Inclusion Criteria:

1. Had unilateral or bilateral OA of the knee diagnosed according to the American College of Rheumatology (ACR) criteria based on clinical and radiographic evidence (presence of osteophytes on x-ray and written evaluation) of OA
2. Had functional capacity class rating of I, II, or III according to ACR classification
3. Had normal 12-lead electrocardiogram (ECG) without any clinically significant abnormalities in heart rate, rhythm, or conduction
4. Had discontinued use of all analgesic medications (including over-the-counter [OTC] analgesics) prior to randomization (patients were allowed limited use of analgesic medications for non study pain
5. At baseline visit, patients were randomized to double-blind treatment if they had an average pain intensity rating for the index joint of 6 or greater (on a 0 to 10 scale) for at least 3 days out of the 5 consecutive days immediately prior to the baseline visit; 0 is defined as "no pain" and 10 is defined as "pain as bad as ever imagined" as measured by Question 5 of the BPI and recorded in a diary
6. At baseline visit, patients were randomized to double-blind treatment if they had, at the baseline visit, an OA severity score for the index joint of 7 or greater on a composite scale of 0 to 24 as measured by the Index of Severity for Osteoarthrosis of the Knee

Key Exclusion Criteria:

1. Had been diagnosed with inflammatory arthritis, gout, pseudo-gout or Paget's disease that in the investigator's opinion would have interfered with the assessment of pain and other symptoms of OA
2. Had serious medical conditions requiring daily medications, such as anticonvulsants and tricyclic antidepressants, that could have confounded study results
3. Had any other clinically significant joint disease or prior joint replacement surgery at the index joint
4. Had severe renal insufficiency (creatinine clearance of <30 mL/min)
5. Had moderate or greater hepatic impairment
6. Were taking analgesic medications, glucosamine, or chondroitin that could not be discontinued during the study. Patients taking these medications prior to the study were required to discontinue use for the duration of the study. Patients using opioid analgesics at study entry were required to taper off these medications.
7. Were taking long-acting opioids or opioids that could not be discontinued over the first 5 days of the placebo run-in period.
8. Were using lidocaine-containing product that could not be discontinued during the study
9. Had previously failed treatment with Lidoderm analgesic patch for OA
10. Had recently received either a corticosteroid injection (within 8 weeks) or hyaluronic acid (within 6 months) of study entry
11. Were unable to discontinue use of topical drugs applied to the knee
12. Were taking class I anti-arrhythmic drugs (e.g. mexiletine, tocainide)