A new delivery method for levodopa/carbidopa, a common dual-drug Parkinson's disease (PD) regimen, significantly improved the duration of the drug's effectiveness in people with advanced PD, according to research by Mount Sinai School of Medicine. The new method is continuous delivery of an intestinal gel formulation of the therapies, which are traditionally taken orally. The study found that the continuous gel delivery reduced "off" time-when the medicine's effectiveness wears off-by an average of nearly two extra hours per day. The gel also improved "on" time without involuntary movements when patients enjoyed a good response, compared to people taking standard levodopa/carbidopa.
The researchers are presenting their findings at the Movement Disorder Society's 16th International Congress of Parkinson's Disease and Movement Disorders being held from June 17-21 in Dublin.
Levodopa is the most effective drug for treating PD, reducing tremors, slowness, stiffness, and walking difficulty, and carbidopa helps prevent nausea and vomiting associated with levodopa. After five to 10 years, however, the duration of its treatment benefits wears off and PD-related symptoms return, representing a major source of disability for patients despite the benefits of the drug. This period of ineffectiveness, which can last six hours or more per day, is known as "off" time.
Researchers led by C. Warren Olanow, MD, Henry P. and Georgette Professor and Chairman Emeritus, Department of Neurology and Director of the Bendheim Parkinson Center at The Mount Sinai Medical Center, performed a double-blind study to explore whether continuous delivery of an intestinal gel form of levodopa/carbidopa could reduce "off" time in people with advanced PD. They found that the levodopa/carbidopa intestinal gel (LCIG) reduced "off" time by nearly four hours, two hours more than standard oral formulations of levodopa.