China's First Homegrown ALS Gene Therapy Achieves 69% Protein Reduction — Published in Nature Medicine
Beijing Tiantan Hospital's neurology team developed RAG-17, China's first domestically developed siRNA drug for ALS, which reduced toxic SOD1 protein by up to 69% in a Phase 1 trial — results published in Nature Medicine.
A Chinese-Made Drug That Silences the Gene Causing ALS
Amyotrophic lateral sclerosis (ALS) — commonly known as "Lou Gehrig's disease" or "motor neuron disease" — progressively destroys the nerve cells controlling voluntary movement. Most patients die within 3-5 years of diagnosis. There is no cure, and existing treatments extend survival by only a few months.
But for the approximately 10% of ALS patients who carry mutations in the SOD1 gene, a new class of treatment has emerged: drugs that silence the defective gene itself, stopping the production of the toxic protein that kills motor neurons.
Now, Beijing Tiantan Hospital (Capital Medical University) has published results of RAG-17 — China's first domestically developed siRNA drug for ALS — in Nature Medicine, one of the world's most prestigious medical journals.
What Is RAG-17?
RAG-17 is a small interfering RNA (siRNA) — a molecule designed to bind to the messenger RNA produced by the mutant SOD1 gene and trigger its destruction before it can be translated into the toxic protein. Think of it as intercepting a dangerous message before it reaches its destination.
The drug was developed jointly by:
- Professor Wang Yilong's team at Beijing Tiantan Hospital's Center for Rare Neurological Diseases
- Professor Li Longcheng's team at Siranomics Nucleic Acid Technology Research Institute
The Phase 1 Trial Results
The trial enrolled 6 Chinese patients with confirmed SOD1 mutations. The results were striking:
| Outcome Measure | Result | Significance |
|---|---|---|
| CSF SOD1 protein reduction | 56-69% decrease | Directly demonstrates the drug is reaching and silencing the target in the central nervous system |
| Plasma neurofilament light chain (NfL) | 52-62% decrease | NfL is a biomarker of nerve damage — reduction indicates less ongoing motor neuron destruction |
| Serious adverse events | Zero | No deaths, no need for mechanical ventilation |
| Adverse events | 2 of 6 patients (33%), all mild-moderate | Acceptable safety profile for a Phase 1 trial |
Why This Is Historically Significant
RAG-17 is the first SOD1-targeting siRNA drug developed entirely by Chinese researchers. Previously, the only available option was tofersen (Qalsody), developed by Ionis/Biogen in the United States and priced at approximately $180,000 per year.
A domestically developed alternative could:
- Dramatically reduce cost — Making gene-silencing therapy accessible to patients who cannot afford imported drugs
- Ensure supply security — Eliminating dependence on foreign pharmaceutical supply chains
- Accelerate development — Chinese clinical trials can enroll patients faster due to the country's large patient population
ALS Treatment Cost: China vs Western Countries
| Treatment | China | United States |
|---|---|---|
| Riluzole (standard, annual) | $500 - $1,500 | $1,500 - $5,000 |
| Tofersen / Qalsody (SOD1-targeted, annual) | Not yet available domestically | $180,000 |
| RAG-17 (estimated, when approved) | Significantly lower than tofersen | N/A |
| Comprehensive ALS evaluation | $1,000 - $3,000 | $5,000 - $15,000 |
| Genetic testing (SOD1 panel) | $300 - $800 | $1,000 - $3,000 |
About Beijing Tiantan Hospital
Beijing Tiantan Hospital is China's premier neurological institution:
- Affiliated with Capital Medical University
- National Neurological Clinical Research Center — China's top designation for neurological research
- Center for Rare Neurological Diseases led by Professor Wang Yilong
- Published in Nature Medicine — one of the world's highest-impact medical journals (IF >80)
- Located in Beijing, with established international patient services
Frequently Asked Questions
Is RAG-17 available for patients now?
RAG-17 is currently in clinical trials (Phase 1 completed). It is not yet commercially available. However, patients with SOD1-mutant ALS may be eligible for expanded access or Phase 2 trials — contact us for the latest enrollment status.
How do I know if I have SOD1-mutant ALS?
Genetic testing can identify SOD1 mutations. This is recommended for all ALS patients, especially those with a family history of the disease. Testing is available at Beijing Tiantan Hospital and can be arranged through SinomedTrip.
Does this drug work for all types of ALS?
No. RAG-17 specifically targets SOD1 mutations, which account for approximately 10% of familial ALS cases. Research into siRNA drugs targeting other ALS-related genes (such as C9orf72 and FUS) is ongoing worldwide.
What current treatment options are available for ALS patients at Beijing Tiantan Hospital?
While the RAG-17 gene therapy is still in clinical development, Beijing Tiantan Hospital offers comprehensive ALS management including riluzole and edaravone therapy, multidisciplinary symptom management covering respiratory support, nutrition, physical therapy, and speech therapy. The hospital's neurology department is one of China's largest and most experienced in neurodegenerative diseases.
Living with ALS or a rare neurological disease? Request a free neurology consultation →
This article is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare provider for diagnosis and treatment decisions.
