Access to the latest research — for scientists and people living with PD alike — in PDF's new scientific journal.
Results In: Levadopa Drug Study
- May 22 2000
A controversy has long reigned over whether patients requiring symptomatic treatment for Parkinson's disease should be started on levodopa (as Sinemet) or on long-acting dopamine (DA) agonists. Those neurologists who advocate levodopa cite its status as the "gold standard" of anti-PD drugs. However, according to many scientists, levodopa may be toxic to already sick DA neurons, and should thus be used only as an add-on to the newer, more long-lasting DA agonists. At the recent American Academy of Neurology meeting, we heard presentations on the disease-modifying effect of ropinirole when used as monotherapy for up to five years, indicating either a protective value for the drug or an escape from the neurotoxicity of levodopa (Dr. David J. Brooks and colleagues, London). At this same meeting, Dr. Amos Korczyn (Tel Aviv) described the safety and efficacy of ropinirole when used in elderly patients (aged seventy-plus), again as monotherapy.
In the newest issue of the New England Journal of Medicine (NEJM) is the complete report on the five-year multi-center study of ropinirole, whose authors (including Drs. Brooks and Korczyn as well as Drs. Olivier Rascol and Anthony E. Lang, all movement disorders specialists) concluded that not only can patients benefit by long-term monotherapy with the drug, but such DA agonists are much less likely to cause the debilitating dyskinesias so common to patients exposes to levodopa therapy.
The study was begun with 179 patients randomized to ropinirole and 89 to levodopa. Approximately half of each group completed the five-year trial, the "endpoint" for each patient coming when he or she required supplementary medication for symptom control. At five years, only twenty percent of the ropinirole group were dyskinetic while 45% of the levodopa group experienced these disabling problems. The evidence for the DA agonist was even more striking in the patients on ropinirole who did not require supplementary levodopa; only five percent of them experienced dyskinesias vs. 36% of those in the early-use levodopa group. There were no differences between the patients in the two groups as to adverse effects, though the incidence of hallucinations was slightly higher (17 to 6%) in the ropinirole-treated patients.
However, these were mild and easily managed in most patients. As many specialists over the past five or more years have concluded, today's patients may benefit better by monotherapy with one of the newer DA agonists, i.e., ropinirole or pramipexole, holding levodopa for use as add-on supplementary treatment after many months of adequate symptomatic control.
Source Date: May 22 2000