Department of Neurology,
University of Miami School of Medicine, 1501 N.W.
9 Avenue, 33136, Miami, FL, USA.
Objective: To assess the long-term
safety and efficacy of pramipexole in advanced Parkinson's
disease over a four year time period.Methods: This
study is an open-label extension trial of pramipexole
for Parkinson's disease open to patients completing
a double-blind placebo controlled safety and efficacy
trial of this drug. Three hundred and six patients
entered the trial. These patients had moderate to
severe PD (stage II-IV Hoehn and Yahr during off time)
and were experiencing motor fluctuations. Patients
were titrated over a six week period and then entered
a maintenance phase which lasted up to 50 months.
Patients were evaluated every 3 months using the Unified
Parkinson's Disease Rating Scale (UPDRS II, III and
IV) and modified Schwab and England scale (S/E).Results:
Sixty-four percent (197) of the 306 patients who entered
this study completed it. Patients showed steady improvement
over the 6 week ascending dose interval when pramipexole
was reintroduced into the trial as the open-label
study medication. Over the duration of the trial patients
slowly returned to their baseline levels. This was
true for all measures evaluated except for the UPDRS
part IV. On UPDRS part IV patients remained below
their baseline score which indicated an improvement
for the duration of the study. Patterns similar to
the overall scores were seen when the individual components
of the UPDRS scale part II for "on" and
"off" periods and part III were evaluated.
However tremor during "on" periods showed
improvement over baseline for the duration of the
trial. The most common adverse events secondary to
pramipexole occurring in greater than 10% of patients
included dyskinesias, asymptomatic orthostatic hypotension,
dizziness, insomnia, and hallucinations.Conclusion:
Pramipexole was well tolerated for up to 4 years.
Pramipexole treatment appeared to show continued efficacy
in the treatment of Parkinson's disease for 3 years
in this open-label descriptive study. After 3 years
there was a gradual return to baseline motor states
perhaps suggesting progression of Parkinson's disease.
