A randomized, double-blind, placebo-controlled, multi-center, phase 3 study to determine the safety and efficacy of TG-C in subjects with Kellgren and Lawrence Grade 2 or 3 Osteoarthritis of the Knee, Osteoarthritis Research Society International (OARSI) medial joint space narrowing (JSN) Grade 1 or 2 of the knee joint. TG-C is to be administered by a single intra-articular injection to the damaged joint area via ultrasound guidance. Patients will be followed for 24 months for safety and efficacy.