바이오스펙테이터

바이오스펙테이터 Euna Lee 기자

▲오원일 메디포스트 부사장

“Our 5-year follow-up study reveals that Cartistem, human umbilical cord blood-derived mesenchymal stem cells, is effective and safe in the treatment of knee cartilage injury or defects, compared with microfracture,” said Oh II-won, vice president of Medipost in a recent press interview at Medipost headquarters in Pangyo, Seongnam-si.

“Clinical findings indicate ultimate therapeutic target of Cartistem when evaluating cartilage injuries and repairs in osteoarthritis, not as a simple pain-relief therapy,” he stated.

Vice President Oh Il-won elaborated the long-term outcome of Cartistem as a therapy having a similar effect to a disease-modifying osteoarthritis drug (DMOAD) that can slow or prevent progression of joint structural changes, coupled with pain-relieving effects associated with osteoarthritis.

Cartistem, a combination of human allogeneic umbilical cord blood-derived mesenchymal stem cells and sodium hyaluronate, is used as a single-dose therapeutic agent for cartilage regeneration in humans with defected knee cartilage due to degeneration or repetitive trauma. Five years have passed since Cartistem was marketed following approval of the Ministry of Food and Drug Safety in 2012.

In the 5-year follow-up study to investigate long-term safety and efficacy of Cartistem, 77 subjects (38: Cartistem group, 39: control group undergoing microfracture) that participated in and completed Phase III trial (for 36±3 months) have been tracked at each point (36, 48, and 60 months). Medipost will present the long-term data of Cartistem this year.

Vice President Oh Il-won emphasized that “Cartistem is the only stem cell therapy with a 5-year long-term data”. He further noted that “The range of motion and function of the knee joint have been monitored from baseline to 60 months based on the scores as assessed by Visual Analogue Scale (VAS), International Knee Documentation Committee (IKDC), and Western Ontario and MacMaster Universities Osteoarthritis Index (WOMIC) in subjects who were either administered Cartistem or treated with conventional microfracture in the primary phase III study.

In particular, differences in degree of improvement in knee assessments from baseline were more significant in the Cartistem group than in the control group at 60 months”.

Re-surgery was conducted in two patients receiving Cartistem versus three patients in the control group from the visit of a last subject in Phase III study to 60 months. However, statistically significant differences were not noted between the two groups.

Vice President Oh Il-won stated that “The two treatments did not show statistically significant differences in the incidence of treatment-related adverse events, including adverse drug reactions and serious adverse events”.

This clearly addresses safety concerns relative to long-term treatment of stem cell-based products.

Degenerative arthritis is characterized by numerous etiological factors, such as joint inflammation and higher oxygen level. With three specific proteins that are secreted by stimulated human allogeneic umbilical cord blood-derived mesenchymal stem cells under the macroenvironment of damaged cartilage lesion site, Cartistem inhibits synthesis and biological activity of proinflammatory cytokines (particularly TNF-α or INF-γ) and matrix metalloproteinase (MMP2), responsible for degradation of cartilage substrate. Ultimately, this will result in facilitating repair of damaged knee cartilage via chondrogenesis of human mesenchymal stem cells.

Vice President Oh Il-won emphasized that “This long-term study suggests that the complex mechanism of Cartistem has significantly contributed to pain reduction for 5 years and in this context, we can postulate that improved joint structural changes and cartilage regeneration can be maintained.”

He predicted that better effect of Cartistem is likely to be clearly visible in the actual clinical practice, since many patients that experienced improvement in the VAS, IKDC and WOMIC scores in the primary Phase III study did not actively participate in this long-term follow-up study.

Vice President Oh Il-won re-emphasized that “Cartistem has a DMOD-like effect, although we cannot define it as DMOD under the current regulation.”

Currently, the U.S. Food and Drug Administration has demanded that biomarker -based studies be conducted for biopharmaceutical developers who intend to seek FDA approval. However, the concept of biomarkers was not firmly established at the time when the first-in-human clinical trial of Cartistem was conducted in Korea in 2005. When Medipost conducted a Phase I trial in the U.S., the FDA had no biomarker-related regulations.

Meanwhile, preclinical studies on diabetic neuropathy and hair loss are also in progress using human allogeneic umbilical cord blood-derived mesenchymal stem cells. In particular, exploration of the development of cellular therapeutic agents has been conducted based on Medipost’s proprietary SUMP-cell platform technology and here, SUMP denotes ‘small, ultra-potent mesenchymal cell scale up. The company has filed a total of 4 SUMP-cell patents in the U.S., Australia and Korea.

“We believe that our SUMP-cell platform, which may contribute significantly to better production yield of existing stem cell, will lead us to develop promising agents in areas of unmet medical need and to lessen government healthcare burden in the long run,” said Vice President Oh Il-won.

“Now that our next-generation pipeline for degenerative arthritis has been under intensive study, we will launch a Phase I study next year at the latest and another pipeline will become Medipost’s future and hope”.