Clinical Trial: Amifampridine Phosphate for the Treatment of Congenital Myasthenic Syndromes

Study Status: Recruiting
Recruit Status: Recruiting
Study Type: Interventional

Official Title: A Phase 3, Double-blind, Outpatient Crossover Study to Evaluate the Efficacy and Safety of Amifampridine Phosphate (3,4 Diaminopyridine Phosphate) in Patients With Congenital Mya

Brief Summary: This randomized, double-blind, controlled, outpatient two-period, two-treatment crossover study is designed to evaluate the efficacy and safety of amifampridine phosphate in patients (ages 2 and above) diagnosed with certain genetic subtypes of CMS and demonstrated open label (amifampridine phosphate) or history of sustained amifampridine benefit from treatment.

Detailed Summary: Each patient will participate in an open-label unblinded drug escalation/treatment run-in phase for up to 4 weeks until stable dose and frequency of amifampridine phosphate is achieved for 7 days. After this phase, blinded treatment effect will be assessed in a randomized fashion of continuation or cessation of drug (Placebo) starting with Period I (duration 7 days). Following experimental Period 1, patients will be returned to the stable dose administered at the end of the open-label run-in period for approximately 2 weeks, followed by cross over treatment in Period 2 dosing for 7 days. After completion of Period 2, patients will be eligible for expanded access with restoration of open-label amifampridine phosphate at the same dose and frequency as established in the run in phase of the study.
Sponsor: Catalyst Pharmaceuticals, Inc.

Current Primary Outcome: Change from baseline in the subject global impression (SGI) scale [ Time Frame: Change from baseline in SGI scores at the end of week 5 (end of Period I) and change from baseline in SGI scores at the end of Week 8 (end of Period 2) ]

The CGI score is a 2-part observer-rated instrument that assesses 1) severity of the patient's disease (CGI S) at a given point in time and 2) change from baseline (CGI-I).


Original Primary Outcome:

  • Change from baseline in the composite motor function measure (MFM) score [ Time Frame: Change from baseline in MFM scores at the end of week 5 (end of Period I) and change from baseline in MFM scores at at the end of week 8 (end of Period 2) ]
    MFM evaluates the severity and progression of motor function
  • Change from baseline in the subject global impression (SGI) scale [ Time Frame: Change from baseline in SGI scores at the end of week 5 (end of Period I) and change from baseline in SGI scores at the end of Week 8 (end of Period 2) ]
    The CGI score is a 2-part observer-rated instrument that assesses 1) severity of the patient's disease (CGI S) at a given point in time and 2) change from baseline (CGI-I).


Current Secondary Outcome: Change from baseline in the Motor Function Measure (MFM) scale [ Time Frame: Change from baseline in MFM scores at the end of week 5 (end of Period I) and at the end of Week 8 (end of Period 2) ]

Original Secondary Outcome:

Information By: Catalyst Pharmaceuticals, Inc.

Dates:
Date Received: September 24, 2015
Date Started: January 2016
Date Completion: October 2017
Last Updated: January 31, 2017
Last Verified: January 2017