South Korea’s Ministry of Food and Drug Safety said today that it has approved the country’s first gene therapy for osteoarthritis, the lead product candidate of a Maryland-based regenerative medicine company.

Invossa-K Inj. was developed by Maryland-based TissueGene, whose Korean licensee, Kolon Life Sciences, won approval for the injectable treatment. According to the company, Invossa is a first-in-class cell-mediated gene therapy designed to treat moderate (Kellgren and Lawrence grade 3) knee osteoarthritis through regeneration of cartilage.

Invossa uses allogeneic human cartilage cells engineered to express transforming growth factor TGF-ß1. TissueGene’s platform technology involves transducing the cells with a retroviral vector engineered to express TGF-ß1 at a specific therapeutic level and duration of time.

The modified cell lines are further selected and screened for cellular expression characteristics intended to minimize patient immune response to the injected cells—then mixed with unmodified cells to create cartilage regeneration via Invossa, as well as bone, disc, and nerve regeneration through the company’s other product candidates.

Invossa is designed for a single injection directly into the knee joint, allowing the cells to induce repair and regeneration of tissue by secreting therapeutic growth factors. The gene therapy—included in GEN’s recent roundup of “Top Trends in Tissue Engineering”—is an alternative to surgery for arthritis patients, according to Kolon.

Kolon has said injection of Invossa has been shown in Phase III trials in Korea to ease the symptoms of about 84% of patients—while 88% of U.S. patients treated with the gene therapy in Phase 2 trials reported improved symptoms for up to two years.

Invossa is being assessed in a Phase III trial in the U.S. after TissueGene and the FDA came to agreement on a Special Protocol Assessment (SPA) for the study. The company is seeking agency approval for the gene therapy as the first disease-modifying osteoarthritis drug (DMOAD).

Kolon has also inked an exclusive licensing and development agreement with Mitsubishi Tanabe Pharma to market the drug in Japan. Under that deal, Mitsubishi Tanabe agreed to pay approximately $24 million upfront plus up to $410 million in payments tied to achieving development, regulatory, and commercial milestones, plus double-digit sales royalties.

In Korea, Mundipharma plans to market and distribute Invossa to general and semiprivate hospitals, while Kolon focuses on general practitioners, under an agreement announced April 11.

With the Korean drug ministry’s approval, Invossa became the 29^th South Korean–developed novel therapy approved by the country’s drug regulatory agency—and one of only four cell gene therapies to have ever been approved globally. The others were approved to treat immunodeficiency diseases, genetic disorders, and cancer.