Abbott has released results from a phase III trial evaluating the company's investigational compound, levodopa-carbidopa intestinal gel (LCIG), for advanced Parkinson's disease.

The study showed that patients treated with LCIG for 12 weeks reported clinically meaningful and statistically significant improvements in "off" time compared to levodopa-carbidopa immediate release tablets, without increasing troublesome dyskinesia. "Off" time refers to the periods of poor mobility, slowness and stiffness experienced by patients with Parkinson's disease.

The study was conducted to determine the efficacy, safety and tolerability of continuous LCIG infusion in patients with advanced Parkinson's disease compared to standard levodopa-carbidopa immediate release tablets. LCIG contains the same active medication as levodopa-carbidopa immediate release tablets but in gel form and is administered directly into the small intestine via a procedurally-implanted tube connected to a portable pump. At baseline, patients enrolled in the study had Parkinson's disease for an average of 10.9 years and experienced an average of 6.6 hours of "off" time a day.

The study’s primary efficacy endpoint was a change from baseline in daily "off" time (16 waking hours) at 12 weeks. Study results showed that patients treated with LCIG experienced a decrease by 4.0 hours per day in mean "off" time at 12 weeks, an average of 1.91 fewer hours of "off" time compared to levodopa-carbidopa immediate release tablets.

The secondary efficacy endpoint was a change from baseline in daily "on" time without troublesome dyskinesias. "On" time refers to periods of good motor symptom control. Study results show that mean "on" time improved by 4.1 hours with LCIG, an average of 1.86 more hours compared to levodopa-carbidopa immediate release tablets.

Treatment-emergent adverse events (AE) occurred in 35 patients on LCIG (95%) and in 34 patients on levodopa-carbidopa immediate release tablets (100%) and were similar between the two treatment groups. The most common adverse events were complication of device insertion, abdominal pain, procedural pain, nausea, constipation, orthostatic hypotension, post-operative wound infection and incision site erythema.

"These results demonstrate that continuous delivery of levodopa-carbidopa intestinal gel produces statistically meaningful improvements in advanced [Parkinson’s disease] patients by decreasing 'off' time and increasing 'on' time without troublesome dyskinetic symptoms," said Dr. C.W. Olanow, M.D., professor of neurology and neuroscience at the Mount Sinai School of Medicine in New York City. "These benefits, in a patient group that cannot be satisfactorily controlled with standard levodopa, represent an important step forward.”

LCIG is currently being evaluated other phase III clinical trials in the U.S. and is already approved in 40 other countries.