Levodopa-Carbidopa Intestinal Gel Prolongs Treatment Benefit In Parkinson's Disease

The 2012 Annual Meeting of the American Academy of Neurology presented a phase 3 randomized, double-blind clinical trial which found that levodopa-carbidopa intestinal gel was more effective than standard oral levodopa-carbidopa.

New Orleans, LA — The Emerging Science program at the 2012 Annual Meeting of the American Academy of Neurology presented a phase 3 randomized, double-blind clinical trial which found that levodopa-carbidopa intestinal gel (LCIG, Abbott) was more effective than standard oral levodopa-carbidopa in reducing the “off” time for patients being treated for advanced Parkinson’s disease (PD).

LCIG is designed to avoid the fluctuating blood levels of oral levodopa-carbidopa, which are thought to contribute to motor complications of PD, explained lead author C. Warren Olanow, MD, professor of neurology and neuroscience at the Mount Sinai School of Medicine in New York City. “The ‘off’ time was reduced because the infusion of LCIG helps to deliver levodopa-carbidopa continuously,” he added.

LCIG is infused through a portable pump which is connected to a tube implanted in the intestine similar to a feeding tube.

The double-blind, double-dummy trial included 71 patients with advanced PD randomized to LCIG (n =3 7) or oral levodopa-carbidopa (n = 34). The mean duration of PD was 10.9 years. Patients received LCIG infusion plus placebo capsules, or levodopa-carbidopa tablets plus placebo gel infusion, for 12 weeks. A total of 93% (n = 66) of the patients completed the trial.

“Off” time refers to the return of PD symptoms such as tremor, slowness, stiffness, and difficulty walking as the beneficial effects of oral treatment wear off. In contrast, “on” time refers to time without troublesome symptoms related to movement. At baseline, the mean “off” time and “on” time without tardive dyskinesia (TD) was 6.6 and 8.3 hours per day.

The use of continuous LCIG reduced “off” time by a mean of 1.91 hours per day (P = .0015). Continuous LCIG improved “on” time without TD by a mean of 1.86 hours per day (P = .0059) compared with patients in the oral levodopa-carbidopa group. No significant benefit for LCIG was observed in “on” time with TD.

LCIG treatment was not associated with an increase in TD. Adverse events were reported in 35 (95%) of those treated with LCIG and 34 (100%) of those receiving oral levodopa-carbidopa. The most common adverse events were related to placement of the intestinal tube including device insertion (51%), abdominal pain (42%), procedural pain (32%), and nausea (25%).

“Less ‘off’ time means more time during the day (where patients experience) improved quality of life. We believe that the benefits observed with LCIG compare favorably with other treatments for PD, such as deep brain stimulation, and avoid the need for an intracranial neurological procedure,” said Dr Olanow.