Levodopa-Carbidopa Intestinal Gel Monotherapy: GLORIA Registry Demographics, Efficacy, and Safety

Background: Continuous delivery of levodopa-carbidopa intestinal gel (LCIG) provides stable plasma levodopa concentrations and reduces motor fluctuations in advanced Parkinson's disease (PD) patients. Objective: To compare the effectiveness and safety of LCIG monotherapy vs polytherapy in patients in the GLORIA registry. Methods: This was a post hoc analysis of a 24-month, multinational observational registry where advanced PD patients with persistent motor complications received LCIG (with adjunctive PD treatment, as necessary). Patients were categorized retrospectively into three stable treatment groups: LCIG monotherapy, LCIG in combination with oral levodopa only ('levodopa monotherapy' [including nighttime oral levodopa]), or LCIG in combination with any other antiparkinsonian medication ('LCIG polytherapy'). Results: Of 356 patients, 208 were on stable regimens (LCIG monotherapy n=80; levodopa monotherapy n=47; LCIG polytherapy n=81). Baseline characteristics were similar across groups. LCIG monotherapy showed significant improvements until month 18 in activities of daily living and quality of life, and until month 24 for Unified Parkinson's Disease Rating Scale (UPDRS) motor examination (p<0.05), 'Off' time (p<0.001), 'On' time with dyskinesia (p<0.01), and non-motor symptoms (p<0.01). More patients in the levodopa monotherapy and LCIG polytherapy groups experienced treatment-related adverse drug reactions (ADRs) including dyskinesias and serious ADRs than did patients in the LCIG monotherapy group. There were few polyneuropathy-related ADRs, of which one case of polyneuropathy led to discontinuation from the Levodopa monotherapy group. Conclusions: These data demonstrate that LCIG monotherapy is an effective treatment option in appropriate advanced PD patients; however, definitive baseline clinical predictors identifying patients who can discontinue concomitant oral therapy have not yet been defined.