REPORT FROM THE AMERICAN ACADEMY OF NEUROLOGY (AAN) ANNUAL MEETING, PHILADELPHIA PA, APRIL 26-MAY 3, 2014 – A new phase II study reports that a novel dry-powder formulation of inhaled levodopa, CVT-301, may be useful for rapid improvement in motor function during Off periods (Freed et al. AAN 2014; abstract S7.007).

According to unpublished phase I results in healthy volunteers, inhaled levodopa achieved therapeutic levels within five minutes of inhalation and resulted in serum drug levels that were less variable than with oral dosing.

The phase II study was designed to evaluate levodopa pharmacokinetics and pharmacodynamics following dry-powder inhalation in 24 patients with Parkinson’s disease on oral levodopa who had periodic motor fluctuations and at least two hours per day of Off time. Subjects received placebo or adjunctive inhaled levodopa (25 or 50 mg) 4-5 hours after the morning dose of oral levodopa (Sinemet 25/100 mg).

There was a dose-proportional increase in levodopa Cmax and area under the curve (AUC) following inhaled CVT-301. With the 50-mg dose, levodopa levels approached therapeutic levels within five minutes of inhalation. Levodopa variability was lower with CVT-301 compared with oral Sinemet. CVT-301 50 mg produced significant improvements in timed tapping and UPDRS scores; improvements in motor response were seen at five minutes post-inhalation. There was no increase in the frequency or severity of dyskinesias. Treatment was well-tolerated and no adverse effects were seen on lung function.

A phase IIb study is currently investigating the use of adjunctive CVT-301 administered as-needed for the treatment of Off episodes.

Guest Reviewer: Dr. Daniel Selchen, Head of Neurology, St. Michael’s Hospital, Toronto, Canada