A Randomized, Controlled, Double-Blind Study of a Single Intra-Articular Injection of the less than 5,000 MW Fraction of Human Albumin 5% (Ampion-Trademark) in Adults with Osteoarthritis of the Knee

This study is testing whether a single injection of a substance called Ampion directly into the knee joint can reduce pain and improve movement in people with knee osteoarthritis (wear-and-tear arthritis). Ampion is derived from human albumin (a natural protein in blood). Participants will receive one of three types of injections and will be followed for 4 days to check for effects and side effects. You may be eligible if: - You are between 40 and 85 years old - You have been diagnosed with moderate knee osteoarthritis (Grade II or III) for at least 6 months - You are able to walk independently - You are able to give written informed consent - You are willing to avoid pregnancy during the study (if applicable) You may NOT be eligible if: - You are pregnant or breastfeeding - You have had a knee injection, surgery, or arthroscopy recently - You have inflammatory arthritis, crystal arthritis, fracture, or severe bone loss - You have a known allergy to human albumin - You have been treated with steroids, anticoagulants, or NSAIDs recently Talk to your doctor about whether this trial might be right for you.