NCT03819660: SMA3

Long Term Safety of Amifampridine Phosphate in Spinal Muscular Atrophy 3

Terminated Phase 2 Results posted Last updated 30 November 2023

What this trial tests

Phase 2 trial testing Amifampridine Phosphate 10 MG Oral Tablet in Spinal Muscular Atrophy Type 3 in 13 participants. Terminated before completion.

Timeline

7 March 2019

Primary endpoint
13 September 2021

13 September 2021

Quick facts

Lead sponsor	Catalyst Pharmaceuticals, Inc.
Phase	Phase 2
Status	Terminated
Study type	INTERVENTIONAL
Allocation	na
Design	single group
Masking	none
Primary purpose	treatment
Enrollment	13
Start date	7 March 2019
Primary completion	13 September 2021
Estimated completion	13 September 2021
Sites	1 location across Italy

Drugs / interventions tested

• Amifampridine Phosphate 10 MG Oral Tablet — full drug profile →

Conditions studied

• Spinal Muscular Atrophy Type 3 — all drugs for Spinal Muscular Atrophy Type 3 →

Sponsor

Catalyst Pharmaceuticals, Inc. — full company profile →

Who can join

Adults 6 to 50, any sex, with Spinal Muscular Atrophy Type 3. Patients with the condition only — healthy volunteers not accepted.

Results — posted to ClinicalTrials.gov

Per-arm endpoint measurements with 95% confidence intervals where reported. Source: trial results section.

Long-term Safety and Tolerability of Amifampridine Primary · 18 months

Number of subjects with treatment emergent adverse events (TEAE).

Group	Value	95% CI
Amifampridine Phosphate	5

To Assess the Clinical Efficacy of Amifampridine Phosphate Over Time in Patients With SMA Type 3 Based on Changes in Quality of Life (QoL). Secondary · Screening to end of study.

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=

screening

Group	Value	95% CI
Amifampridine Phosphate	33.737	± 17.677

End of Study

Group	Value	95% CI
Amifampridine Phosphate	39.012	± 14.337

Adverse events — posted to ClinicalTrials.gov

Time frame: 27 months. Reporting threshold: 5%. Adverse-event reports describe events observed during the trial — not all are caused by the drug.

Amifampridine Phosphate

Serious: 1/13 (8%)

Deaths: 0/13

Serious adverse events (1 terms)

Reaction	System	Amifampridine Phosphate
Intellectual Disability	Nervous system disorders	—

Other adverse events (13 terms — click to expand)

Reaction	System	Amifampridine Phosphate
Paraesthesia oral	Gastrointestinal disorders	—
ABDOMINAL PAIN UPPER	Gastrointestinal disorders	—
HYPERPYREXIA	General disorders	—
FEELING HOT	General disorders	—
INFLUENZA LIKE ILLNESS	General disorders	—
MALAISE	General disorders	—
FALL	Injury, poisoning and procedural complications	—
POST LUMBAR PUNCTURE SYNDROME	General disorders	—
HYPOKALAEMIA	Metabolism and nutrition disorders	—
Paraesthesia	Nervous system disorders	—
HEADACHE	Nervous system disorders	—
TREMOR	Nervous system disorders	—
RASH	Skin and subcutaneous tissue disorders	—

Most-reported serious reactions: Intellectual Disability.

Data from ClinicalTrials.gov NCT03819660 adverse events section.

Sponsor's own description

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

Publications & conference data

4 peer-reviewed publications reference this trial (live from Europe PMC):

1. Therapy development for spinal muscular atrophy: perspectives for muscular dystrophies and neurodegenerative disorders.
   Jablonka S, Hennlein L, Sendtner M. · · 2022 · cited 37× · PMID 34983696 · DOI 10.1186/s42466-021-00162-9
2. Drug Screening and Drug Repositioning as Promising Therapeutic Approaches for Spinal Muscular Atrophy Treatment.
   Menduti G, Rasà DM, Stanga S, Boido M. · · 2020 · cited 27× · PMID 33281605 · DOI 10.3389/fphar.2020.592234
3. In Search of a Cure: The Development of Therapeutics to Alter the Progression of Spinal Muscular Atrophy.
   Ojala KS, Reedich EJ, DiDonato CJ, Meriney SD. · · 2021 · cited 16× · PMID 33562482 · DOI 10.3390/brainsci11020194
4. An updated review of the SMA clinical trial landscape in the United States: Findings from analysis of recruitment targets on ClinicalTrials.gov and a survey of SMA clinical trial sites on factors affecting site capacity and readiness.
   Sarr F, Peterson I, Glascock J, Curry M. · · 2026 · cited 1× · PMID 41658435 · DOI 10.1016/j.conctc.2026.101601