Double-Blind, Randomized, Single Dose Escalation Safety Study of Intraarticular Bone Morphogenic Protein (38A BMP-7) in Subjects With Osteoarthritis (OA) of the Knee

Inclusion Criteria * Ambulatory with a diagnosis of OA of the knee with symptoms for at least 6 months and pain on the majority of days in the last 30 days. * \>40 years * Radiographic evidence of at least one osteophyte in either knee at screening Exclusion Criteria * Concurrent medical or arthritis condition that could interfere with evaluation of index knee joint (including fibromyalgia) * Unwilling to abstain from NSAIDs and/or other analgesic medications for 48 hrs prior to assessments. Subjects can remain on acetaminophen up to 3.0 g daily. * Received arthroscopic or open surgery to the index knee within 6 months of screening * History of joint replacement surgery (index knee). * Corticosteroid, short acting hyaluronic acid, or other intraarticular injections of the index knee within 3 months of screening * Long acting hyaluronic acid injection of the index knee within 6 months of screening * History of Reiter's syndrome, rheumatoid arthritis, psoriatic arthritis, ankylosing spondylitis, lymphoma, and arthritis associated with inflammatory bowel disease, sarcoidosis, amyloidosis or fibromyalgia. * History of malignancy with the exception of resected basal cell, squamous cell of the skin, resected cervical atypia or carcinoma in situ. * Female subject with reproductive capability.