A Study to Assess Safety and Tolerability of PCRX-201 in Subjects With Painful Osteoarthritis of the Knee

The study will consist of two parts, Part A and Part B, which will use PCRX-201 from two different manufacturing processes. A total of 135 eligible subjects, with painful OA of the index knee will be enrolled. Subjects will be randomly assigned to a treatment dose group, stratified by Kellgren-Lawrence (K-L) Grade, in both parts of the study. Enrollment of subjects with K-L Grade 4 will be capped at 4 subjects per dose group in Part A and 8 subjects per dose group in Part B. Enrollment of subjects with K-L Grade 2 or 3 will include a minimum of 4 subjects per Grade per dose group in Part A and a minimum of 8 subjects per Grade per dose group in Part B. This study does not require an equal number of subjects between K-L Grade 2 and 3. All eligible subjects will be pretreated with the same dose of methylprednisolone acetate (40 mg) on Day 1 immediately before treatment with PCRX-201 or placebo. Part A will enroll approximately 45 subjects into 3 dose groups (15 subjects in each treatment group, stratified by K-L Grade as noted above). Part B will enroll approximately 90 subjects into 3 groups (30 subjects in each treatment group, stratified by K-L Grade as noted above). Enrollment in Part B is dependent upon the availability of study drug developed with manufacturing process 2.