Jointstem, a stem cell therapy for degenerative arthritis, failed to obtain conditional approval. The therapy is an autologous adipose-derived mesenchymal stem cell injection, developed by Nature Cell.

The Ministry of Food and Drug Safety (MFDS)’s Central Pharmaceutical Affairs Council reviewed giving the nod to Jointstem at a meeting on Tuesday. However, the ministry said it concluded that Nature Cell’s plan for the clinical trials and study results were not valid for conditional approval.

The regulatory agency gives a conditional approval by reviewing phase-2 clinical trials data, on the condition that the drugmaker submits phase-3 trials materials, usage data, and safety use measures (such as specific use within a particular medical institution) to the regulator later.

In 2016, the ministry included cell therapies in the review list of conditional approval as long as they can be used to treat a life-threatening disease or an irreversible disease that makes symptoms get worse once it develops.

Nature Cell applied for conditional approval because degenerative arthritis is an irreversible disease that symptoms do not improve quickly. To get the regulatory approval, the pharmaceutical company submitted to the ministry interim data of the clinical trials in patients suffering the severity at Kellgren & Lawrence (K-L) Grade 3 or higher in the U.S.

The drugmaker conducted the phase-2 trials on 19 patients at K-L Grade 3 or 4 in the U.S. The study administered Jointstem to 13 patients, and Synvisc to six, comparing WOMAC (Western Ontario and McMaster Universities Arthritis Index) score that measures the severity of arthritis, VAS (Visual Analog Scale) measuring pain, and cartilage improvement in MRI (magnetic resonance imaging) scans.

Six months after the treatment of Jointstem, the patients’ WOMAC average score went down by 67.4 percent from 36.38 to 11.86. VAS fell by 69.9 percent from 57 to 17.15, and MRI scans also improved, according to Nature Cell.

However, the minutes of the ministry’s council revealed that the council members did not trust the results of the Jointstem clinical trials.

The study had too few specimens at 13, and MRI scans showed that 53.85 percent of patients, who were treated with Jointstem, experienced a progression of the disease. For such reasons, the council did not regard the trials as successful. Jointstem was not as effective as platelet-rich plasma (PRP) therapy either, according to the council members.

The council also pointed out that the study failed to provide reliable results for joint projection, joint regeneration, pain reduction, and anti-inflammation, which had been expected in a mesenchymal stem cell therapy.

The council noted that the trials did not control the variable correctly, either. The study allowed patients who had taken a combination therapy to participate in the tests as long as 30 days have passed since the administration of the combo.

However, effects of corticosteroids for arthritis treatment usually last for about 90 days and hyaluronic acid also lasts for at least six months. Patients who had 30 days past after the combo medication were allowed to participate in the study. In other words, the company conducted the trials in a situation where the effect of the combination therapy could not be excluded.

The council concluded that Nature Cell’s clinical trials plan for conditional approval for Jointstem and the study results were not valid.

lhs@docdocdoc.co.kr

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