Gene therapy relieves Parkinson's symptoms

Researchers are testing gene therapy for Parkinson's disease

01/10/2014

Gene therapy offers promising new approaches to the treatment of Parkinson's disease. For decades, scientists worldwide have sought ways to treat the previously incurable degenerative neurological disease. Now has a British-French research team in the journal „The Lancet“ published a study, which concludes that the so-called ProSavin gene therapy at least a significant improvement in motor skills in Parkinson's patients can be achieved.

To date, Parkinson's disease is usually treated with an oral dopamine replacement therapy, however, the long-term treatment leads to significant side effects, such as „Pulse control disorders caused by intermittent stimulation of dopamine receptors and side effects“, The research team reports to Professor Stéphane Palfi from the Faculty of Medicine of the University of Paris. In her recent study, the efficacy and tolerability of alternative treatment based on ProSavin gene therapy was investigated. This had proven to be quite effective and well tolerated.

Gene therapy boosts dopamine production in the brain
In ProSavin gene therapy, scientists use seeded viruses as carriers for DNA sequences or genes that play a key role in dopamine production. These are injected into the brain of the patient and then automatically incorporated into certain brain cells, whereupon the production of dopamine in the brain increases significantly. Thus, caused by dopamine deficiency motor disorders of Parkinson's patients such as muscle twitching or the typical tremors and balance disorders significantly. The researchers have now studied the effectiveness of this method in 15 Parkinson's patients between the ages of 48 and 65 years. All subjects had been suffering from the neurological disorder for at least five years. Patients received different doses of ProSavin (three received low doses, six were median, six high) and were subsequently followed for at least 12 months.

No serious side effects
Be from the patients „54 drug-related adverse events (51 mild, three moderate)“ reported within the follow-up period, the researchers report. The most common complaints were so-called dyskinesias (disorders of movement). However, according to Palfi and colleagues, serious adverse events due to study medication or surgical procedures were not reported. After six months, all patients had a significant improvement in motor skills. The higher the dose administered, the clearer was this improvement in the motor skills of the patients. In some patients the effect lasted up to four years. Subsequently, however, the limitations of the motor skills in view of the progression of the disease again came significantly to bear.

Other aspects of Parkinson's disease are not considered
In a comment on the article in the trade magazine „The Lancet“ criticizes Jon Stoessl of the Pacific Parkinson's Research Center at the University of British Columbia and Vancouver that the current gene therapy approach had a proven effect on the motor skills of patients, but here the other symptoms of the disease would be neglected. Thus, the cognitive deficits and the changes in the character are for many patients a much greater impairment than the motor difficulties. A meaningful treatment method would therefore also have to consider these aspects. (Fp)