Clinical Trial Details
— Status: Recruiting
Administrative data
NCT number |
NCT04773470 |
Other study ID # |
DYSSMA1 |
Secondary ID |
|
Status |
Recruiting |
Phase |
N/A
|
First received |
|
Last updated |
|
Start date |
February 1, 2022 |
Est. completion date |
April 1, 2024 |
Study information
Verified date |
November 2023 |
Source |
University of Giessen |
Contact |
Samra Hamzic, MA |
Phone |
+4964198559233 |
Email |
samra.hamzi[@]neuro.med.uni-giessen.de |
Is FDA regulated |
No |
Health authority |
|
Study type |
Interventional
|
Clinical Trial Summary
The major aim of this project is to assess comprehensively frequency and extent of dysphagia
and bulbar dysfunction in SMA1, 2, and 3 patients by applying FEES and validated dysphagia
scores. Further aims are to follow changes of dysphagia over time in newly diagnosed
patients, and in subjects starting treatment with one of the new therapeutic SMA drugs.
Special attention will be paid to subjects treated with Risdiplam. If applicable, the data
will be compared between groups receiving different drugs.
Description:
Spinal muscular atrophy (SMA) is a progressive autosomal recessive neuromuscular disease
characterized by premature degeneration of the 2nd motor neuron and a broad phenotype. SMA
results from biallelic mutations in the SMN1 gene at 5q13. SMN1 encodes the SMN protein that
is essential for proper function of the anterior horn cells. The estimated incidence is 1 per
6000-11 000 births. The classification of SMA is based on age at symptom onset and maximum
motor function achieved. SMA1 patients develop symptoms within the first 6 months of life and
do not achieve sitting without support. SMA2 patients typically show first symptoms from 6 to
18 months and never learn to walk. SMA3 patients display first clinical signs after the age
of 18 months and achieve walking. Rarely, patients develop first symptoms in adulthood
(SMA4). While defects in SMN1 are the cause of SMA, the severity of disease is related to the
copy number of SMN2, a paralogous gene located next to SMN1 that differs from SMN1 by 5
nucleotides only. This results in a splicing defect reducing the amount of SMN protein
produced by one copy of SMN2 to about 10%.
The clinical hallmarks of SMA are progressive muscle weakness and muscular atrophy. Scoliotic
deformities, contractures, reduced head control, limited jaw closure, coughing difficulties,
and impaired clearance of tracheal secretions are common problems. In many patients, bulbar
muscle weakness including dysphagia represents a great diagnostic and therapeutic challenge.
Treatment of SMA remained purely symptomatic for many decades, but this has changed
fundamentally within the last years, since several therapeutic agents have been developed
targeting to correct causal disease mechanisms. Nusinersen, an antisense oligonucleotide
modifying SMN2 splicing, has been approved in the US and in Europe. Onasemnogene abeparvovec,
an AAV9-mediated gene therapy, provides patients with intact SMN1 copies and has also been
licensed in the US and in Europe. Finally, Risdiplam, an oral splicing modifier acting on
SMN2, has been approved in the US and is currently available in Germany for SMA1 and 2
patients via a compassionate use program. Data from two recent studies, FIREFISH (SMA1) and
SUNFISH (SMA2/3) have shown significant improvements in motor and bulbar functions in
Risdiplam treated individuals.
Although these new therapies will substantially modify the course of disease and improve the
prognosis of SMA, the treatment of clinical symptoms and their diagnosis will remain
challenging. Dysphagia of variable degree often necessitating artificial feeding to prevent
malnutrition and low body weight occurs in all types of SMA. Poor sucking, swallowing
difficulties, and inadequate mobilization of mucous with increased risk of aspiration and
pneumonia are frequent in SMA1, while restricted jaw mobility and opening as well as weakness
of the jaw muscles are common in SMA2 and 3. Altogether, dysphagia represents an important
factor of morbidity in SMA, and adequate diagnosis and care of this symptom are essential to
maintain quality of life. To achieve this, the application of validated diagnostic methods
and scales are necessary. But until now, only a few retrospective studies with small numbers
of patients or case reports dealing with dysphagia in SMA are on record, and no standardized
assessments using validated tests have been applied. Moreover, no larger study has
systematically analyzed which percentages of SMA1, 2, and 3 patients suffer from dysphagia,
and no data are available about severity of dysphagia in the single types. Furthermore, it is
not known, which effects on swallowing the new therapeutic agents have.
Flexible Endoscopic Evaluation of Swallowing (FEES) is the gold standard of swallowing
imaging, but has not yet been comprehensively and prospectively used for analysis of the
swallowing process in SMA. In patients with neurogenic dysphagia, validated dysphagia
severity scores in tandem with FEES are used since many years, and allow early detection and
improved management of swallowing disorders.