Infantile spinal muscular atrophy (SMA-I)
About
SMA-I is the most severe type of SMA, with a severe deficiency of survival motor neuron protein (SMN) caused by homozygous deletions or mutations in the SMN1 gene. SMN protein is crucial for the survival of motor neurons. Core dilemmas: ① Motor neurons begin to degenerate during the fetal period, and the first three months after birth is the most critical window for treatment and intervention;② Those who fail to intervene in time die before the age of 2;③ The one-time cost of gene therapy (Zolgensma) is as high as 2.1 million US dollars, although it has significant efficacy, it is expensive.
Features & Symptoms
- The disease occurs within 6 months of birth
- Severe muscle weakness, difficulty breathing and swallowing
- Can't sit alone and look up
- Motor neurons begin to degenerate during the fetal period
Treatment Options
| Treatment | Description | Stage | Price Range |
|---|---|---|---|
| Zolgensma gene replacement therapy | The AAV9 vector delivers normal SMN1 gene to motor neurons with one-time gene replacement. The FDA approved that the earlier the intervention, the better the effect, at a one-time cost of approximately US$2.1 million but can change the natural course of the disease. | FDA批准 | $1M - $2.1M/次（一次性） |
| Spinraza（nusinersen） | Intrathecal injection of ASO increases the production of functional SMN protein by modifying SMN2 gene splicing. It requires lifelong administration and is injected intrathecally every 4 months. | FDA批准 | $150K - $750K/年 |
| Evrysdi（risdiplam） | Oral small-molecule drugs also increase SMN protein by modifying SMN2 gene splicing. It is suitable for patients who cannot tolerate intrathecal injection. | FDA批准 | $100K - $300K/年 |
Prognosis
Those who did not intervene in time died before the age of 2
Additional Notes
Notes: Treatment window: The first 3 months after birth is the golden window for treatment, and the earlier the intervention, the better the effect; neonatal screening: SMA screening is recommended for all newborns. Early detection and early intervention can significantly improve the prognosis; gene therapy evaluation: Onasemnogene abeparvovec (Zolgensma) is suitable for patients with SMA-1 with a body weight of less than 13.5kg, and liver function and pre-stored AAV9 antibodies need to be evaluated; Drug selection: Nusinersen (intrathecal injection) and Risdiplam (oral) can also be selected, each of the three drugs has its advantages and disadvantages; Respiratory management: Respiratory function needs to be monitored regularly, and non-invasive ventilation is used if necessary. Exclusive service commitment: The platform will allocate a dedicated medical team to each patient to assist in dismantling and properly deploying the following precautions throughout the process. When cross-state and cross-border diagnosis and treatment projects or drugs are involved, the platform will make overall arrangements for the entire docking; for disabled and semi-disabled patient groups, the platform will provide rush-free alternative solutions (including remote consultation, door-to-door sampling, direct drug delivery in the cold chain, etc.), to ensure that patients can get the same high-quality diagnosis and treatment resources without having to travel in person.; Study phase: FDA approval. Prognosis: Those who did not intervene in time died before the age of 2.
Frequently Asked Questions
What is Infantile spinal muscular atrophy (SMA-I)?
SMA-I is the most severe type of SMA, with a severe deficiency of survival motor neuron protein (SMN) caused by homozygous deletions or mutations in the SMN1 gene. SMN protein is crucial for the survival of motor neurons. Core dilemmas: ① Motor neurons begin to degenerate during the fetal period, and the first three months after birth is the most critical window for treatment and intervention;② Those who fail to intervene in time die before the age of 2;③ The one-time cost of gene therapy (Zolgensma) is as high as 2.1 million US dollars, although it has significant efficacy, it is expensive.
What are the symptoms of Infantile spinal muscular atrophy (SMA-I)?
The disease occurs within 6 months of birth,Severe muscle weakness, difficulty breathing and swallowing,Can't sit alone and look up,Motor neurons begin to degenerate during the fetal period
How is Infantile spinal muscular atrophy (SMA-I) treated?
Zolgensma gene replacement therapy: The AAV9 vector delivers normal SMN1 gene to motor neurons with one-time gene replacement. The FDA approved that the earlier the intervention, the better the effect, at a one-time cost of approximately US$2.1 million but can change the natural course of the disease.; Spinraza（nusinersen）: Intrathecal injection of ASO increases the production of functional SMN protein by modifying SMN2 gene splicing. It requires lifelong administration and is injected intrathecally every 4 months.; Evrysdi（risdiplam）: Oral small-molecule drugs also increase SMN protein by modifying SMN2 gene splicing. It is suitable for patients who cannot tolerate intrathecal injection.
What is the prognosis for Infantile spinal muscular atrophy (SMA-I)?
Those who did not intervene in time died before the age of 2