Long Term Safety of Amifampridine Phosphate in Spinal Muscular Atrophy 3 (SMA3)

Long Term Safety Study of Amifampridine Phosphate in Ambulatory Patients With Spinal Muscular Atrophy (SMA) Type 3

A long term safety study of amifampridine phosphate in patients with spinal muscular atrophy (SMA) Type 3.

Study Overview

• Status: Terminated
• Conditions: Spinal Muscular Atrophy Type 3
• Intervention / Treatment: Drug: Amifampridine Phosphate 10 MG Oral Tablet

Detailed Description

This open-label outpatient extension study was designed to evaluate the long-term safety and tolerability of amifampridine in patients diagnosed with SMA Type 3. In addition, the evaluation of the effects of amifampridine on the QoL was performed. The study was planned to enroll those patients who had completed the SMA-001 study and after all final evaluations for that study had been completed, or those who demonstrated benefit after completing the dose titration period but failed to meet the randomization criteria on Day 0 of SMA-001.

The duration of participation for each patient was expected to be at least 12 months as patients could continue in the study until amifampridine was approved by Regulatory Agencies or the clinical development of amifampridine was terminated for this indication. In addition to amifampridine, patients continued to receive previous concomitant medications, as needed.

• Study Type: Interventional
• Enrollment (Actual): 13
• Phase: Phase 2

Contacts and Locations

Study Locations

• Italy
  • Lombardy
    • Milano, Lombardy, Italy, 20133
      • Neurological Institute Carlo Besta

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 6 years to 50 years (Child, Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

Individuals eligible to participate in this study must meet all the following inclusion criteria:

1. Participated in the SMA-001 study
2. Willing and able to provide written informed consent after the nature of the study has been explained and before the start of any research-related procedures.
3. Female patients of childbearing potential must have a negative pregnancy test (urine human chorionic gonadotropin [HCG] at the end of SMA-001 study); and must practice an effective, reliable contraceptive regimen during the study and for up to 30 days following discontinuation of treatment.
4. Ability to participate in the study based on overall health of the patient and disease prognosis, as applicable, in the opinion of the Investigator; and able to comply with all requirements of the protocol, including completion of study questionnaires.

Exclusion Criteria:

Individuals who met any of the exclusion criteria in the original protocol or those listed below are not eligible to participate in the study:

1. Epilepsy and currently on medication.
2. Uncontrolled asthma.
3. Concomitant use with sultopride.
4. Concomitant use with medicinal products with a narrow therapeutic window.
5. Concomitant use with medicinal products with a known to cause QTc prolongation.
6. Clinically significant abnormalities in 12 lead ECG, in the opinion of the Investigator.
7. Subjects with congenital QT syndromes.
8. Breastfeeding or pregnant at Screening or planning to become pregnant at any time during the study.
9. Intolerable amifampridine-related side effects
10. Treatment with an investigational drug (other than amifampridine) or device while participating in this study.
11. Any medical condition that, in the opinion of the Investigator, might interfere with the patient's participation in the study, poses an added risk for the patient, or confound the assessment of the patient.
12. History of drug allergy to any pyridine-containing substances or any amifampridine excipient(s).

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: amifampridine phosphate; The dose of amifampridine was based on optimal neuromuscular benefit determined from the Run-in Period from SMA-001 or could be modified as the discretion of the Investigator. The maximum single dose was 20 mg. The dose range for patients 6 to 16 years of age was 15 to 60 mg, and for those 17 years and older the range was from 30 to 80 mg daily.	Drug: Amifampridine Phosphate 10 MG Oral Tablet; Oral tablets

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Long-term Safety and Tolerability of Amifampridine	Number of subjects with treatment emergent adverse events (TEAE).	18 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
To Assess the Clinical Efficacy of Amifampridine Phosphate Over Time in Patients With SMA Type 3 Based on Changes in Quality of Life (QoL).	Quality of life (QoL): the Individualized Quality of Life for neuromuscular disease (INQoL) or the Pediatric Quality of Life (PEDSQLTM) was used for adult or pediatric patients, respectively. Since there were no pediatric patients, none of the patients completed the PEDSQL. The INQol evaluated weakness, pain, fatigue, double vision, muscle locking, droopy eyelids, swallowing difficulties, activities, social relationships, emotions and body image. Each of these areas were measured in four categories as follows: 1- Incidence (0= No, 1 =Yes), 2-Severity (0= None to 7 = extreme), 3- Impact - (0= None to 6 = extreme) and 4-Importance (0= None to 6 = extreme). The numbers were summative and are input to the QOL calculation, which is a percentage of severity on a scale of 0-100. The mean value was taken across this population. The higher scores were a worse outcome.	Screening to end of study.

Collaborators and Investigators

• Sponsor: Catalyst Pharmaceuticals, Inc.
• Investigators: Principal Investigator: Lorenzo Maggi, MD, Carlo Besta Institute, Milan, Italy

Study record dates

Study Major Dates

• Study Start (Actual): March 7, 2019
• Primary Completion (Actual): September 13, 2021
• Study Completion (Actual): September 13, 2021

Study Registration Dates

• First Submitted: January 23, 2019
• First Submitted That Met QC Criteria: January 24, 2019
• First Posted (Actual): January 28, 2019

Study Record Updates

• Last Update Posted (Actual): November 30, 2023
• Last Update Submitted That Met QC Criteria: November 29, 2023
• Last Verified: November 1, 2023

More Information

Terms related to this study

• Keywords: Type 3
• Additional Relevant MeSH Terms: Central Nervous System Diseases; Nervous System Diseases; Neurologic Manifestations; Neuromuscular Diseases; Neurodegenerative Diseases; Neuromuscular Manifestations; Pathological Conditions, Anatomical; Spinal Cord Diseases; Motor Neuron Disease; Muscular Atrophy; Atrophy; Muscular Atrophy, Spinal; Physiological Effects of Drugs; Molecular Mechanisms of Pharmacological Action; Peripheral Nervous System Agents; Membrane Transport Modulators; Neuromuscular Agents; Potassium Channel Blockers; Amifampridine
• Other Study ID Numbers: SMA-002

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No