Levodopa Pharmacokinetics in Patients With Parkinson’s Disease and Symptom Fluctuation: A Phase I, Open-label, Randomized, Multicentre, Crossover Study Comparing Intravenous and Subcutaneous Infudopa With Intestinal Duodopa

Status: 
Recruiting
Sponsor: 
Vastra Gotaland Region
Enrollment: 
28
Study Design: 
The current study is a prospective, 3-period-cross-over, open-label multicentre trial comparing i.v. and s.c. administration of the study drug, Infudopa, to Duodopa. The study is including advanced Parkinson’s patients who are already on a stable regimen of LCIG for at least 30 days with a dose between 685mg to 4000mg and be using it for 16- or 24-h. Standard exclusionary criteria apply. The study is being conducted in Sweden and requires three treatment visits. The study has a cross-over design with a minimum of 3 days of Duodopa in between the treatment visits. At each visit, the participant will receive either standard Duodopa infusion, Infudopa intravenously or Infudopa subcutaneously over a 16-h period. The order of the treatment will be non-blinded but randomized. A pre-study optimum dose of Duodopa will be established that will determine the dose of the i.v. and s.c. Infudopa that will yield a corresponding serum levodopa level. The Infudopa i.v. will be dosed at 75% of participant’s individual pre-study Duodopa dose and administered via an indwelling catheter in the arm as a morning rapid constant dose followed by continuous i.v. infusion up to 16-h. Similarly, Infudopa s.c. will be administered over 16-h as a morning rapid constant rate followed by continuous infusion dosed similarly to pre-study Duodopa dose for the participant.
Rationale: 
The primary objective focuses on demonstrating two major pharmacokinetic points. 1. To demonstrate that a steady state plasma concentration of levodopa and carbidopa, equivalent to that of Duodopa, can be achieved after the i.v. and s.c. infusion of Infudopa. 2. To demonstrate that peak-trough fluctuations of levodopa and carbidopa plasma concentrations during the dosage interval of both i.v. and s.c. Infudopa will be comparable to that of Duodopa. Secondary objectives are designed to look at the 1. Safety profile, particularly focusing on local skin reactions, 2. Expanded pharmacokinetic profile of both levodopa and carbidopa after s.c. and i.v. administration compared to Duodopa. The parameters being checked include bioavailability, maximum plasma concentration, time to maximum plasma concentration, area under the curve, and elimination half-life. 3. Effect on clinical parameters focusing on bradykinesia, dyskinesia, and tremors using the clinical rating scale UPDRS and objective assessments via Parkinson’s Kinetigraph.
Comments: 
Infudopa aims to demonstrate an equally efficacious alternative s.c. delivery of carbidopa/levodopa compared to LCIG. If the results are positive, it will be another alternative to LCIG. The Infudopa IntraV, if successful in demonstrating meaningful clinical benefit, will be a potentially interesting addition for use in peri-operative scenarios. Since these are still early phase studies, they rightly aim to demonstrate clinically acceptable PK and safety profile of the active drugs.