Hyper- and Hypokalemic Periodic Paralysis Study

2010-07-15 17:00:00 | BioPortfolio


The purpose of this study is to compare Dichlorphenamide with placebo (an inactive substance) for prevention of episodes and for improvement of strength in periodic paralysis. This study will also look at the long-term effects of Dichlorphenamide in periodic paralysis.


Periodic paralysis is a relatively rare, life-long disorder characterized by intermittent bouts of paralysis, progressive weakness, and diminished quality of life. Two drugs, acetazolamide and dichlorphenamide, have been prescribed to treat the disorder, however, dichlorphenamide is no longer available.

In this multi-center, parallel, randomized trial researchers will compare the effects of dichlorphenamide vs. placebo in patients with hyperkalemic (HYP) and hypokalemic (HOP) periodic paralysis.

The trial consists of two 9-week studies—one study will enroll persons with hyperkalemic periodic paralysis and the other study will enroll persons with hypokalemic periodic paralysis. Participants will be randomly assigned to one of two treatment groups: dichlorphenamide or placebo (an inactive substance). During the studies, participants will be asked to keep a daily computer diary to record the time, length, and severity of each episode of weakness. The study coordinator will contact participants weekly to review the diary information.

The 9-week phase will be followed by a 1-year open-label dichlorphenamide extension without placebo to determine the long-term effects of dichlorphenamide on the course of the disease and on inter-attack weakness.

Duration of the trial for participants is approximately 65 weeks, including a screening phase to determine eligibility, the first 9-week treatment phase, and the one-year open-label extension phase.

Study Design

Allocation: Randomized, Control: Placebo Control, Endpoint Classification: Efficacy Study, Intervention Model: Parallel Assignment, Masking: Double Blind (Subject, Investigator), Primary Purpose: Treatment


Periodic Paralysis


Dichlorphenamide, Placebo


University of California-San Francisco
San Francisco
United States




University of Rochester

Results (where available)

View Results


Published on BioPortfolio: 2010-07-15T17:00:00-0400

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