Parkinson's stem-cell treatment used in Japan first

A patient in Japan has received a pioneering stem-cell treatment for Parkinson's disease in what drugmaker Sumitomo Pharma described as a world first after conditional approval in the country.

Sumitomo Pharma said Friday that the first transplant was performed at Kyoto University Hospital in October. The company gave no further details about the patient.

The treatment involves transplanting millions of induced pluripotent stem cells, or iPS cells, into a patient's brain. iPS cells are mature cells that have been induced to return to a juvenile state, allowing them to develop into different cell types.

Under the treatment, iPS cells from healthy donors are developed into precursors of dopamine-producing brain cells, which are no longer present in people with Parkinson's.

Japanese regulators conditionally approved the therapy in March after a clinical trial. In that trial, seven patients aged 50 to 69 received implants of either five million or 10 million cells on both sides of the brain and were monitored for two years. No major adverse effects were found, and four patients showed symptom improvements.

Sumitomo Pharma said it plans to carry out transplants on 20 to 30 patients by March 2029 and is also conducting a clinical trial in the United States. Local media said the treatment will gain full approval in Japan if its safety and efficacy are confirmed over the next seven years.

Parkinson's disease is a chronic degenerative neurological disorder that affects movement. The Parkinson's Foundation estimates that more than 10 million people worldwide have the illness and says currently available therapies improve symptoms without slowing or halting disease progression.