Kolon TissueGene held a corporate briefing for investors on July 16 to discuss the status and potential success of TG-C’s clinical trials in the United States. TG-C is the world’s first cell and gene therapy for osteoarthritis, involving the injection of cartilage-derived cells combined with TGF-β1 into the knee to treat osteoarthritis. If TG-C successfully passes its final clinical trial in the U.S., the world’s largest pharmaceutical market, it could become a groundbreaking treatment for degenerative arthritis and gain global recognition.
Kolon TissueGene CEO Noh Moon-jong expressed optimism about the clinical trial’s success. “Given that the results of the U.S. Phase 2 clinical trial were replicated in the Korean Phase 3 trial, we expect similar outcomes in the U.S. Phase 3 trial,” he said. The Korean Phase 3 trial previously indicated that TG-C tended to delay the progression of knee osteoarthritis.
The briefing was held about a week after the completion of TG-C Phase 3 trial dosing in the U.S. on July 10. Phase 3 is the final stage of clinical trials required for market approval, following Phase 1 safety tests and Phase 2 efficacy tests. This phase ultimately evaluates the treatment’s effectiveness, benefits, and potential side effects.
TG-C has faced a challenging development journey. Despite receiving approval from South Korea’s Ministry of Food and Drug Safety in 2017, the U.S. Food and Drug Administration (FDA) halted the trial in 2019 upon discovering that Kolon TissueGene had used kidney-derived cells instead of cartilage-derived cells. This led to the cancellation of its domestic approval. However, Kolon TissueGene argued that the medication itself was not problematic and clarified the situation to the FDA. In 2020, the FDA accepted their explanation, allowing the resumption of the U.S. Phase 3 trial and recognizing the validity of previous clinical data.
The company resumed patient recruitment the following year. On July 10, it completed the dosing phase of the U.S. clinical trial, which began in 2006, and now moves into the follow-up phase. Over the next two years, Kolon TissueGene will monitor the progress of 1,066 patients to finalize the Phase 3 trial results. A Kolon TissueGene representative stated, “If everything goes as planned, we anticipate being able to market TG-C in the U.S. around 2028.” Given that no current medications fundamentally treat osteoarthritis and with 38 million osteoarthritis patients in the U.S. alone (as of 2020), the company expects TG-C to become a ‘global blockbuster drug’ with annual sales exceeding 1 trillion won if the clinical trials are successful.
Kolon TissueGene is also preparing for FDA approval by negotiating with contract manufacturing organizations (CMOs) like Lonza and Kolon Biotech for mass production, ensuring readiness for immediate market release upon approval. Additionally, the company plans to develop TG-C for other types of arthritis, including hip and spinal disc arthritis.
While the company remains optimistic, securing FDA approval is not an easy task. According to the Biotechnology Innovation Organization (BIO), the average success rate for Phase 3 clinical trials in the U.S. is around 50%.
