Kolon TissueGene presented compelling long-term safety and efficacy data for its investigational knee osteoarthritis therapy TG-C at the 2025 Osteoarthritis Research Society International (OARSI) World Congress held in Songdo, South Korea from April 24-27. The data highlights TG-C's potential to become the first disease-modifying osteoarthritis drug (DMOAD) to receive FDA approval.
The presentation, titled "TG-C, the First Potential DMOAD Therapy: Intra-Articular Cell-Based Gene Therapy with Long-Term Safety and Insight into Delaying Total Knee Arthroplasty (TKA)," showcased nearly 15 years of clinical observation data supporting the therapy's safety profile and preliminary efficacy benefits.
Robust Long-Term Safety Profile
The safety analysis included 33 subjects from the U.S. Phase 2 trial and 110 subjects from the Phase 3 trial who completed two years of follow-up. Notably, no treatment-related tumor cases were reported in TG-C-treated subjects during the extended observation period of nearly 15 years.
Further strengthening the safety case, age-specific cancer incidence among TG-C subjects was consistently lower compared to the general U.S. population, based on Surveillance, Epidemiology, and End Results (SEER) data from the U.S. National Cancer Institute.
Potential to Delay Knee Replacement Surgery
Perhaps most significant were the efficacy findings comparing knee replacement rates between TG-C-treated subjects and the broader osteoarthritis population. According to data from the Osteoarthritis Initiative (OAI), a longitudinal study sponsored by the U.S. National Institutes of Health (NIH), 15.5% of 595 patients meeting TG-C-eligible criteria underwent total knee arthroplasty (TKA) at a median of 5.1 years after osteoarthritis onset.
In contrast, only 7.0% of TG-C-treated subjects required knee replacement surgery, with the median time to surgery extended to 5.7 years. These results suggest TG-C may either eliminate the need for surgery in some patients or significantly delay surgical intervention—a key characteristic of a disease-modifying therapy.
The ongoing Phase 3 trial data were analyzed in a blinded manner, including both TG-C and placebo arms, allowing for an objective evaluation of the long-term safety and treatment effects.
Executive Perspectives
Dr. Moon Jong Noh, Co-CEO of Kolon TissueGene, expressed optimism about the therapy's future: "We are honored to share meaningful TG-C data at the first-ever OARSI congress held in Korea. This opportunity reinforces our optimism for FDA approval and recognition of TG-C as the world's first DMOAD therapy."
Co-CEO Seng Ho Jeon, who joined the company in March, added: "The scientific data presented strongly supports the safety and efficacy of TG-C. We are pursuing parallel strategies for both regulatory approval and commercialization to establish TG-C as a global blockbuster treatment."
Market Potential
TG-C represents a significant advancement in osteoarthritis treatment as the world's first cell and gene therapy developed specifically for knee osteoarthritis. It is classified as a first-in-class investigational drug and is currently in the follow-up phase of its U.S. Phase 3 trial.
The market opportunity is substantial. As of 2024, the osteoarthritis market in the seven major countries (U.S., France, Germany, Italy, Spain, U.K., and Japan) is estimated at KRW 3.8 trillion, with projections to reach KRW 5.5 trillion by 2031, representing a compound annual growth rate of 5.3%. The global market is expected to exceed KRW 12 trillion.
Currently dominated by low-cost analgesics that primarily address symptoms rather than disease progression, the introduction of effective disease-modifying therapies like TG-C could significantly expand the market potential while addressing a critical unmet need for the millions of patients suffering from knee osteoarthritis worldwide.
About OARSI
The Osteoarthritis Research Society International (OARSI), headquartered in New Jersey, USA, is the world's leading organization for scientists and healthcare professionals working in osteoarthritis prevention and treatment. This year marked the first time the prestigious society hosted its annual congress in Korea, drawing over 1,500 experts from more than 50 countries, including clinical researchers, orthopedic specialists, radiologists, and physical therapists.
