Inclusion Criteria:  Diagnosis of knee OA by clinical criteria (American College of Rheumatology). Identification of knee osteoarthritis by a radiologist on an existing knee radiograph obtained within 3 years of enrollment. Moderate to severe knee pain for at least 3 months, defined as a score of ≥ 4 (on a 0-10 point numeric rating scale) in response to the question "What is the average level of your left/right knee pain in the past 3 months?".  Exclusion Criteria:  Pregnancy. Diabetes. Anticoagulation therapy. History of total knee replacement. Prior knee prolotherapy or other regenerative product. Any knee injection within 3 months. Inflammatory (RA, gout, pseudogout etc.) or postinfectious knee arthritis. Daily use of opioid medication. Allergy or intolerance to study medication, corn allergy. Body mass index (BMI) greater than 40 kg/m^2. Comorbidity severe enough to prevent participation in the study protocol.