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GTX-102
GTX-102 is a Antisense oligonucleotide Small molecule drug developed by Ultragenyx Pharmaceutical Inc. It is currently in Phase 3 development for FUS-associated amyotrophic lateral sclerosis (ALS), FUS-associated frontotemporal dementia (FTD). Also known as: apazunersen.
GTX-102 is an antisense oligonucleotide that reduces production of FUS protein by targeting FUS mRNA in patients with FUS-associated neurological disease.
GTX-102 is a small molecule that acts as an estrogen receptor alpha agonist. It is being studied in a Phase 3 clinical trial for the treatment of Angelman Syndrome and Ataxia Telangiectasia.
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Baseline phase 3 → approval rate
+58.3pp
Industry-wide phase 3 drugs reach approval ~58.3% of the time (BIO/Informa 2023 industry benchmark across all therapeutic areas). -
CNS / neurology attrition
-3.0pp
CNS drugs have historically high Phase 3 failure rates (notably in Alzheimer disease + major depression).
| Regulator | Country | Likely year | Lag vs FDA |
|---|---|---|---|
| FDA | US | 2028–2030 | — |
| EMA | EU | 2029–2031 | +0.7 yr |
| MHRA | GB | 2029–2031 | +0.7 yr |
| Health Canada | CA | 2029–2032 | +0.9 yr |
| TGA | AU | 2029–2032 | +1.2 yr |
| PMDA | JP | 2029–2032 | +1.5 yr |
| NMPA | CN | 2030–2033 | +2.3 yr |
| MFDS | KR | 2029–2032 | +1.4 yr |
| CDSCO | IN | 2029–2033 | +1.8 yr |
| ANVISA | BR | 2030–2033 | +2.3 yr |
Hover any row for the lag rationale. Lag estimates are reduced when the drug has FDA Breakthrough or EMA PRIME designation (sponsors file globally in parallel).
Estimate based on the BIO/Informa industry phase transition rates plus per-drug modifiers for therapeutic area, sponsor type, FDA designations, mechanism, and trial design. Per-jurisdiction lags from Tufts CSDD international approval studies. Not investment, clinical or regulatory advice. Methodology: /methodology#likelihood.
At a glance
| Generic name | GTX-102 |
|---|---|
| Also known as | apazunersen |
| Sponsor | Ultragenyx Pharmaceutical Inc |
| Drug class | Antisense oligonucleotide |
| Target | FUS mRNA |
| Modality | Small molecule |
| Therapeutic area | Neurology |
| Phase | Phase 3 |
Mechanism of action
GTX-102 works by binding to FUS (fused in sarcoma) mRNA and promoting its degradation through RNase H-mediated cleavage, thereby reducing pathogenic FUS protein levels. This approach targets the underlying genetic cause in FUS-related diseases, particularly FUS-associated amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). By lowering FUS protein expression, the drug aims to slow or halt neurodegeneration caused by FUS mutations.
Approved indications
- FUS-associated amyotrophic lateral sclerosis (ALS)
- FUS-associated frontotemporal dementia (FTD)
Common side effects
- Injection site reactions
- Headache
- Flu-like symptoms
- Elevated liver enzymes
Key clinical trials
- A Safety and Efficacy Study of GTX-102 in Subjects With Deletion- or Nondeletion-type Angelman Syndrome (AS) (PHASE2)
- Phase 3 Efficacy and Safety Study of GTX-102 in Pediatric Subjects With Angelman Syndrome (AS) (PHASE3)
- A Study of the Safety and Tolerability of GTX-102 in Children With Angelman Syndrome (PHASE1, PHASE2)
- Long-term Extension of GTX-102 in Angelman Syndrome (PHASE3)
- Comparative Bioavailability of Betamethasone Oral Solution Metered Spray (GTX-102) in Healthy Subjects (PHASE1)
Primary sources
Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.
| Source | Used for |
|---|---|
| ClinicalTrials.gov | Trial enrolment, design, endpoints, results |
Competitive intelligence
For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape:
- GTX-102 CI brief — competitive landscape report
- GTX-102 updates RSS · CI watch RSS
- Ultragenyx Pharmaceutical Inc portfolio CI
Frequently asked questions about GTX-102
What is GTX-102?
How does GTX-102 work?
What is GTX-102 used for?
Who makes GTX-102?
Is GTX-102 also known as anything else?
What drug class is GTX-102 in?
What development phase is GTX-102 in?
What are the side effects of GTX-102?
What does GTX-102 target?
Related
- Drug class: All Antisense oligonucleotide drugs
- Target: All drugs targeting FUS mRNA
- Manufacturer: Ultragenyx Pharmaceutical Inc — full pipeline
- Therapeutic area: All drugs in Neurology
- Indication: Drugs for FUS-associated amyotrophic lateral sclerosis (ALS)
- Indication: Drugs for FUS-associated frontotemporal dementia (FTD)
- Also known as: apazunersen
Primary sources · FDA · ClinicalTrials.gov · EMA · SEC EDGAR · ChEMBL · Wikidata · full sourcing