Safety and Efficacy of NMD670 in Ambulatory Adult Patients With Type 3 Spinal Muscular Atrophy (SYNAPSE-SMA)

June 2, 2026 updated by: NMD Pharma A/S

A Phase 2, Randomised, Double-blind, Placebo-controlled, 2-way Crossover Study to Evaluate the Efficacy, Safety, and Tolerability of NMD670 in Ambulatory Adults With Type 3 Spinal Muscular Atrophy

The purpose of this study is to evaluate the efficacy, safety, tolerability and pharmacokinetics of NMD670 in the treatment of ambulatory adults with spinal muscular atrophy type 3

Study Overview

Status

Completed

Conditions

Intervention / Treatment

Study Type

Interventional

Enrollment (Actual)

52

Phase

  • Phase 2

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • Belgium
      • Leuven, Belgium
        • UZ Leuven - Neurochirurgie Campus Gasthuisberg
      • Liège, Belgium
        • CHR de la Citadelle - Neurologie
  • Canada
      • Calgary, Canada
        • Heritage Medical Research Clinic
      • Montreal, Canada
        • Genge Partners Inc.
  • Denmark
      • Aarhus, Denmark
        • Aarhus Universitetshospital, Neurologisk Afdeling
      • Copenhagen, Denmark
        • Rigshospitalet - Neurologisk Afdeling
  • Germany
      • Berlin, Germany
        • Charite - Campus Virchow-Klinikum (CVK)
      • Essen, Germany
        • Universitätsklinikum Essen - Klinik Für Neurologie
  • Italy
      • Genova, Italy
        • Istituto Giannina Gaslini, IRCCS
      • Milan, Italy
        • Istituto Neurologico C. Besta, Fondazione IRCCS
      • Milan, Italy
        • Ospedale Niguarda, ASST Grande Ospedale Metropolitano Niguarda
      • Torino, Italy
        • AOU Città della Salute e della Scienza di Torino
  • Netherlands
      • Utrecht, Netherlands
        • Universitair Medisch Centrum Utrecht, locatie Academisch Zie - Neurology
  • Spain
      • Barcelona, Spain
        • Hospital Universitari Vall d Hebron
      • Madrid, Spain
        • Hospital Materno Infantil La Paz
      • Valencia, Spain
        • Hospital Universitario Y Politecnico La Fe
  • United States
    • California
      • Los Angeles, California, United States, 90095
        • UCLA David Geffen School Of Medicine - Neurology
      • Palo Alto, California, United States, 94304
        • Stanford University Medical Center
    • Kansas
      • Kansas City, Kansas, United States, 66160
        • University of Kansas Medical Center
    • Maryland
      • Baltimore, Maryland, United States, 21287
        • The Johns Hopkins Medicine, Spinal Muscular Atrophy Center
    • Missouri
      • Columbia, Missouri, United States, 65212
        • Roy Blunt NextGen Precision Health Institute
      • St Louis, Missouri, United States, 63110
        • Washington University School of Medicine
    • North Carolina
      • Hillsborough, North Carolina, United States, 27278
        • Rare Disease Research - Raleigh-Durham
    • Ohio
      • Columbus, Ohio, United States, 43210
        • The Ohio State University Wexner Medical Center
    • Texas
      • Denton, Texas, United States, 76208
        • Neurology Rare Disease Center

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

18 years to 60 years (Adult, Older Adult)

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  1. Participants with a clinical diagnosis of Type 3 SMA.
  2. Participants who are ambulatory, defined as being able to walk at least 50 metres without walking aids at screening during the 6-minute walk test.
  3. Participant with genetic confirmation of diagnosis (e.g., homozygous deletion or compound heterozygous deletion and mutation of survival of motor neuron 1 gene [SMN1])
  4. Participant with 3 to 5 copies of survival of motor neuron 2 gene [SMN2].
  5. Participant has a body mass index (BMI) within the range 19-35 kg/m2 (inclusive).
  6. Participant is male or female.
  7. Contraceptive use by men and women must be consistent with local regulations regarding the methods of contraception for those participating in clinical studies.
  8. Participant is capable of giving signed informed consent which includes compliance with the requirements and restrictions listed in the informed consent form (ICF) and in the protocol.

Exclusion Criteria:

  1. Participants with prior surgery or fixed deformity (scoliosis, contractures) which would restrict ability to perform study-related tasks.
  2. Participants with other significant disease that may interfere with the interpretation of study data (e.g., other neuromuscular or muscular diseases).
  3. Participants with other significant clinical and/or laboratory safety findings that may interfere with the conduction or interpretation of the study
  4. Participants received treatment with an investigational medical product (IMP) within 30 days (or 5 half-lives of the medication, whichever is longer) prior to Day 1.
  5. Participants with history of poor compliance with relevant SMA therapy.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Crossover Assignment
  • Masking: Triple

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Cohort 1
Experimental drug followed by placebo
Drug: Placebo
Tablets
Drug: NMD670
Tablets
Experimental: Cohort 2
Placebo followed by experimental drug
Drug: Placebo
Tablets
Drug: NMD670
Tablets

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Change from baseline in 6 minute walk test (6MWT) total distance versus placebo
Time Frame: Baseline to day 21
Distance walked (meters)
Baseline to day 21

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Change from baseline in muscle strength versus placebo
Time Frame: Baseline to day 21
Handgrip, knee flexor, elbow flexor, elbow extension and should abduction (Newton)
Baseline to day 21
Change from baseline in 6 minute walk test (6MWT) fatigue index versus placebo
Time Frame: Baseline to day 21
percentage change in distance walked in 6th minute compared to 1st minute
Baseline to day 21
Change from baseline in jitter versus placebo
Time Frame: Baseline to day 21
Jitter (micro seconds) assessed with single fiber EMG
Baseline to day 21
Change from baseline in blocking versus placebo
Time Frame: Baseline to day 21
Blocking (%) assessed with single fiber EMG
Baseline to day 21
Incidence of treatment emergent adverse events
Time Frame: Over 21 days of dosing
Summarised per treatment
Over 21 days of dosing
Incidence of serious treatment emergent adverse events
Time Frame: Over 21 days of dosing
Summarised per treatment
Over 21 days of dosing
Incidence of clinically significant abnormalities on physical examinations
Time Frame: Over 21 days of dosing
Summarised per treatment
Over 21 days of dosing
Incidence of clinically significant abnormalities on safety laboratory parameters
Time Frame: Over 21 days of dosing
Summarised per treatment
Over 21 days of dosing
Incidence of clinically significant vital signs abnormalities
Time Frame: Over 21 days of dosing
Summarised per treatment
Over 21 days of dosing
Incidence of clinically significant ECG abnormalities
Time Frame: Over 21 days of dosing
Summarised per treatment
Over 21 days of dosing
Change from baseline in Revised Hammersmith Scale (RHS) versus placebo
Time Frame: Baseline to day 21
Total score. Scale goes from 0-69 and higher score indicates improvement of symptoms
Baseline to day 21
Incidence of Suicidal Ideation or Suicidal Behavior
Time Frame: Over 21 days of dosing
Summarised per treatment
Over 21 days of dosing
Incidence of clinically significant abnormalities on opthalmological examinations
Time Frame: Over 21 days of dosing
Summarised per treatment
Over 21 days of dosing

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

NMD Pharma A/S

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

September 21, 2023

Primary Completion (Actual)

May 11, 2026

Study Completion (Actual)

May 18, 2026

Study Registration Dates

First Submitted

March 15, 2023

First Submitted That Met QC Criteria

March 29, 2023

First Posted (Actual)

April 3, 2023

Study Record Updates

Last Update Posted (Actual)

June 3, 2026

Last Update Submitted That Met QC Criteria

June 2, 2026

Last Verified

June 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • NMD670-02-0001
  • 2022-002301-24 (EudraCT Number)

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

product manufactured in and exported from the U.S.

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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