A randomized, double-blind, placebo-controlled trial of subcutaneously injected apomorphine for parkinsonian off-state events.

OBJECTIVE To assess the safety and efficacy of subcutaneous apomorphine hydrochloride administration for off-state (poor motor function) periods in patients with Parkinson disease with motor fluctuations under both inpatient titration and outpatient therapeutic conditions. PATIENTS AND METHODS Twenty-nine patients had advanced Parkinson disease with 2 hours or more off time despite aggressive oral therapy. Patients randomly received titrated doses of subcutaneous apomorphine hydrochloride (2-10 mg, n = 20) or pH-matched vehicle placebo (n = 9) during an inpatient and 1-month outpatient phase. A change in the United Parkinson Disease Rating Scale motor score 20 minutes after inpatient dosing during a practically defined off-state event and the percentage of injections successfully aborting off-state events were the primary inpatient and outpatient efficacy factors. RESULTS The average (SEM) levodopa equivalent dose of apomorphine hydrochloride was 5.4 +/- 0.5 mg and the mean placebo dose was 1.0 mL. Mean inpatient United Parkinson Disease Rating Scale motor scores were reduced by 23.9 and 0.1 points (62% and 1%) by apomorphine treatment and placebo, respectively (P<.001). The mean percentage of outpatient injections resulting in successful abortion of off-state events was 95% for apomorphine and 23% for placebo (P<.001). Inpatient response was significantly correlated with and predictive of outpatient efficacy (P<.001). The levodopa dose was not predictive of the apomorphine dose requirement. Frequent adverse events included dyskinesia, yawning, and injection site reactions. CONCLUSION Apomorphine by intermittent subcutaneous injection is effective and safe for outpatient use to reverse off-state events that occur despite optimized oral therapy.