Photo/Illutration The Asahi Shimbun

An existing drug for Parkinson’s disease can delay the progress of amyotrophic lateral sclerosis (ALS) by about seven months, according to a clinical trial using induced pluripotent stem (iPS) cell technology.

Keio University researchers released the results of the trial on May 20. They will apply for approval to use the drug to treat ALS as soon as possible after considering the need to conduct additional clinical trials.

It is the first time in the world that the efficacy of drugs discovered through “drug discovery and development” methods, which include experiments using iPS cells, has been confirmed in a clinical trial.

Under the methods, medical professionals can create a large amount of nerve and muscle cells using iPS cells based on cells harvested from patients to reproduce the patients' conditions.

They can then use those cells to test thousands of chemical compounds and pick drug candidates more quickly.

The research team replicated ALS patients' conditions by using iPS cells based on cells harvested from them. The team tried about 1,230 types of drugs, leading to the discovery that ropinirole hydrochloride, a drug for Parkinson’s disease, is likely to be effective for ALS.

In 2018, the researchers began a clinical trial involving 20 ALS patients aged between 43 and 79 who developed symptoms within five years and could perform daily activities with some assistance.

Of these, 13 took ropinirole hydrochloride and seven received a placebo for half a year. All 17 participants who continued to take part in the trial took ropinirole hydrochloride for the following six months.

The median time for those who were administered ropinirole hydrochloride for a year to become unable to walk without assistance or begin having difficulty swallowing was approximately 50 weeks, 195 days longer than those who received the placebo for the first six months.

No participants stopped taking the drug for such reasons as side effects.

ALS is an incurable disease in which nerve damage causes patients to progressively lose control of their muscles and gradually become completely paralyzed. A specific protein that accumulates in patients’ nerve cells and other factors are thought to induce the illness.

Drugs and rehabilitation can slow the progression of the disease, but an effective treatment has yet to be established.