Welcome to the English webpage of the LEAP-study: Levodopa in EArly Parkinson’s disease.

The LEAP-study is a clinical study which will assess the long term effects of levodopa in Parkinson’s disease. All 446 patients have been recruited. The last measurement is completed in November 2017. Publication of the first results is expected in 2018.


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Summary of research protocol

The current mainstay of PD-treatment consists of dopamine replacement with levodopa or dopamine-agonists.
There is considerable debate about when and how to initiate pharmacological therapy. Although current guidelines indicate that symptomatic treatment for Parkinson’s disease (PD) should be started when functional health is hindered, most neurologists still delay starting symptomatic treatment. This results in an acceptance of disability early in the disease.
The results of recent studies suggest that early treatment with levodopa might have a — thus far unrecognized — delayed beneficial effect on PD symptoms.

To investigate whether early treatment with levodopa has a delayed beneficial effect on:
• PD symptoms and functional health;
• improves the ability to (maintain) work; and
• reduces the use of (informal) care, caregiver burden, and costs.
Additionally, cost-effectiveness and cost-utility of early levodopa treatment will be assessed.

Study design
The study is a prospective, randomized, delayed-start, double blind, placebo-controlled multicenter trial and started in August 2011.
In 30 months 446 patients with newly diagnosed PD, that do not need symptomatic treatment judged by the treating neurologist, will be included.
For 40 weeks, patients will receive either levodopa/carbidopa 100/25 mg TID or placebo; the last 40 weeks, all patients will receive levodopa/carbidopa 100/25 mg TID.
There are 8 assessments, all of which will be performed by trained research-nurses.

Outcome measures
The primary outcome measure is the difference between the early-start group and the delayed-start group after 80 weeks, measured with the Unified Parkinson’s Disease rating scale (UPDRS).
Secondary outcome measures include:
• the AMC Linear disability Scale (ALDS);
• side effects;
• Parkinson’s Disease Questionnaire-39;
• the EuroQol-5D;
• ability to (maintain) work, the use of (informal) care, caregiver burden, and costs.

Steering Committee
• Rob de Bie
• Marcel Dijkgraaf
• Bob van Hilten
• Teus van Laar
• Bart Post
• Gerrit Tissingh

Advisory Board
• Bas Bloem
• Günther Deuschl (Germany)
• Elisabeth Foncke
• Rob de Haan
• Anthony Lang (Canada)