The primary objective of this study is to demonstrate superior efficacy of tanezumab 5 mg and 2.5 mg administered subcutaneously (SC) every 8 weeks versus placebo at Week 24 in subjects with osteoarthritis of the knee or hip. The 2.5 mg dose was shown to provide efficacy benefits with a favorable safety profile when administered intravenously in previous Phase 3 clinical trials. The 5 mg dose is expected to provide added efficacy benefit over the 2.5 mg dose based on data from previous studies.