Researchers in a national study, including neurologists at the University of Maryland School of Medicine, found that a gel form of Parkinson's medications, administered directly into a patient's small intestine, works better than standard oral medications in reducing "off" times in patients with advanced Parkinson's disease (PD). "Off" times occur when standard oral medicines wear off, causing the return of symptoms such as tremor, slowness, stiffness and walking difficulty.
Investigators presented results of the Phase III trial at the American Academy of Neurology's 64th Annual Meeting in New Orleans.
"With this levodopa-carbidopa intestinal gel [LCIG], a pump infuses the drugs through a tube implanted in the small intestine, similar to a feeding tube," says William Weiner, MD, professor and chair of the Department of Neurology at the University of Maryland School of Medicine. "This is a new way to administer the most beneficial PD drug, levodopa, and it appears to be effective in this Phase III trial. This gel may prove to be an alternative for more advanced patients considering Deep Brain Stimulation surgery."
In the three-month double-blind study, researchers randomized 71 participants to receive either continuous infusion of LCIG and placebo pills or a placebo intestinal gel and pills that contained levodopa and carbidopa. The study found that the continuous LCIG reduced "off" time by an average of nearly two hours a day, without an increase in troublesome dyskinesia, a common side effect of Parkinson's medicines, which cause involuntary and uncontrolled dance-like movements. The gel also improved "on" time, providing patients good control with fewer side effects than the oral medication.
"At the start of the study, the average patient had more than 6 1/2 hours of 'off' time. More hours of quality 'on' time and lessening the amount of 'off' time by several hours can make a huge difference in people's lives," adds Weiner, who also directs the Parkinson's Disease and Movement Disorders Center at the University of Maryland Medical Center. "This added time may allow people to spend more time with their families and friends or simply go shopping or take a walk, which can greatly affect a person's quality of life," he says.
Researchers think the continuous infusion of the gel avoids the fluctuation of medication levels associated with oral therapy, and the gel may also avoid side effects that come with long-term use of oral medication.
"Results of this study may lead to new options for patients considering brain surgery as their Parkinson's disease progresses. The University of Maryland School of Medicine's participation in this national research reflects our faculty's commitment to finding new treatment options for their patients," says E. Albert Reece, MD, PhD, MBA, vice president for medical affairs, University of Maryland, and the John Z. and Akiko K. Bowers Distinguished Professor and dean, University of Maryland School of Medicine.
Abbott Laboratories, the company developing the new intestinal gel, supported the study, the results of which will be submitted to the U.S. Food and Drug Administration for approval. The most common side effects for the gel involved complications due to inserting the device, including pain during the procedure, abdominal pain and nausea.
Parkinson's disease affects about 1 million people in the United States and Canada. Most people begin to develop symptoms in their late 50s or early 60s, although it can occur in younger people. Parkinson's disease affects the brain's ability to produce dopamine, the neurotransmitter involved in the communication between the brain cells for motor control. Physical symptoms include tremor, muscle rigidity, and slowness of movement. There are also non-motor symptoms such as changes in memory ability, sleep disturbances, and depressed mood.