Results of levodopa-carbidopa intestinal gel study for Parkinson’s disease presented


Abbott has announced results from five abstracts evaluating levodopa-carbidopa intestinal (LCIG) gel, its investigational compound for advanced Parkinson’s disease. The abstracts include the results from the second interim analysis of a long-term safety and tolerability trial, as well as secondary endpoint analyses from the phase III pivotal trial. All of the abstracts were presented at the 16th International Congress of Parkinson’s Disease and Movement Disorders (17–21 June, Dublin, Ireland)

Long-term safety and tolerability

In a 54 week open-label safety and tolerability study of 354 patients with advanced Parkinson’s disease, the primary endpoint of safety showed adverse events were mostly mild to moderate, were generally associated with the Percutaneous Endoscopic Gastrostomy (PEG) tube placement procedure and its complications, were transient, and resolved over time.

In the secondary endpoint analysis from the open-label study, patients experienced an average daily “off” time of 6.7 hours, and 7.7 hours of “on” time without troublesome dyskinesia at baseline. “Off” time refers to periods of poor mobility, slowness and stiffness experienced by patients with Parkinson’s disease, while “on” time refers to periods of good motor symptom control. At week 54, mean daily “off” time had decreased an average of 4.5 hours, and “on” time without troublesome dyskinesia had increased by 5.1 hours. “On” time with troublesome dyskinesia decreased an average of 0.6 hours.

“Despite the many advances that have been made over the years in treating patients with Parkinson’s disease, managing motor complications such as wearing off in the advanced stages of the condition continues to be challenging for physicians, patients and their caregivers,” said CW Olanow, professor of Neurology and Neuroscience at the Mount Sinai School of Medicine in New York City, USA. “Data from the various clinical trials evaluating LCIG suggest that patients with advanced Parkinson’s disease may benefit from continuous intestinal infusion of levodopa and carbidopa.”

The most common treatment emergent adverse events were complication of device insertion (33.1%), abdominal pain (30%), procedural pain (21.7%) and nausea (16.1%). The most common serious treatment emergent adverse events were complication of device insertion (6.5%), abdominal pain (3.1%) peritonitis (2.8%) and polyneuropathy (2.8%).

Twenty-six patients (7.3%) withdrew due to at least one adverse event; 17 of these patients withdrew due to at least one serious adverse event. Gastrointestinal- and PEG-related issues were the most common cause of withdrawal from the study.

Phase 3 Efficacy

Functional and quality of life secondary endpoint analyses from a twelve-week double-blind, double-dummy pivotal trial of 71 patients comparing LCIG to standard levodopa-carbidopa immediate release (LC-IR) tablets were also presented.

The primary endpoint of this study showed a reduction in mean daily “off” time of 4.0 hours, a statistically significant difference of 1.91 fewer hours spent in “off” time with LCIG compared to LC-IR tablets. These data were previously presented at the American Academy of Neurology Annual Meeting (21–28 April, New Orleans, USA). The most common adverse events were complication of device insertion (51%), abdominal pain (42%), procedural pain (32%), nausea (25%), constipation (21%), orthostatic hypotension (18%), post-operative wound infection (17%), and incision site erythema (16%). 

“We are pleased to showcase the clinical trial results being presented for LCIG in patients with advanced Parkinson’s disease,” said Robert Lenz, divisional vice president, Global Pharmaceutical Research and Development, Abbott. “Obtaining pivotal and supportive clinical data is a critical stage in the overall development process of LCIG and further supports our efforts to develop LCIG for advanced Parkinson’s disease patients in the USA who are in need of alternative therapies.”

It is estimated that at least three million people worldwide have been diagnosed with Parkinson’s disease. As the disease progresses, the effect of oral medications may not last as long and can cause increasing side effects. Patients with advanced Parkinson’s disease may experience fluctuations between bradykinetic (slowness of movement) and hyperdyskinetic (involuntary movement) states.

LCIG is currently approved in 40 countries. In the USA, LCIG is an investigational therapy that is currently being evaluated in patients with advanced Parkinson’s disease in additional Phase 3 clinical trials.