Intestinal gel reduces ‘off’ time in advanced Parkinson’s disease


A levodopa-carbidopa intestinal gel works better than standard oral levodopa-carbidopa in reducing “off” time in patients with advanced Parkinson’s disease, according to results of a phase three randomised, double-blind clinical trial presented as part of the Emerging Science programme at the American Academy of Neurology’s 64th Annual Meeting in New Orleans, USA. 

The intestinal gel contains levodopa and carbidopa, two drugs commonly prescribed for Parkinson’s, and is infused through a portable pump connected to a tube implanted in the intestine, similar to a feeding tube.

“Off” time occurs when Parkinson’s symptoms like tremor, slowness, stiffness and walking difficulty return as the beneficial effects of oral treatments wear off.

‘“Off’ time was reduced because the infusion of levodopa-carbidopa intestinal gel helps to deliver levodopa-carbidopa continuously, thereby avoiding the fluctuating levels that occur with standard oral levodopa-carbidopa therapy and that are thought to contribute to the development of wearing off,” said C Warren Olanow, professor of Neurology and Neuroscience at the Mount Sinai School of Medicine, New York, USA, and author of the study.

In the three-month double-blind trial, 71 participants were randomised to receive either the continuous infusion of levodopa-carbidopa intestinal gel and dummy pills or a dummy intestinal gel and pills that contained levodopa and carbidopa. At the start of the study, the average person had Parkinson’s disease for about 11 years and experienced 6.6 hours of “off” time per day. A total of 93% of participants completed the study.

The study found that the continuous levodopa-carbidopa intestinal gel reduced ‘off’ time by an average of nearly two extra hours per day and improved “on” time without troublesome movements by an average of two hours per day compared to people taking standard levodopa-carbidopa. Treatment with levodopa-carbidopa intestinal gel was also not associated with an increase in troublesome dyskinaesia.

“Less ‘off’ time for people with Parkinson’s means more time during the day in which they can enjoy the benefits of levodopa-carbidopa therapy and experience improved quality of life. We believe that benefits observed with this method of treatment compare favourably with other methods for treatment, such as deep brain stimulation, and avoid the need for an intracranial neurosurgical procedure,” said Olanow.