Follistatin-344
Also referenced as: FS344, FS315 precursor
A follistatin precursor isoform whose gene-transfer studies are often confused with injected protein products.
- Evidence grade
- DPreclinical Research
Preclinical Research
- Regulatory status
- Research Use Only
Not FDA-approved for the research uses discussed; no established clinical enhancement indication.
- Human data
- No
No registered clinical trials identified
- Last reviewed
- October 27, 2026
Overview
A follistatin precursor isoform whose gene-transfer studies are often confused with injected protein products.
Not FDA-approved for the research uses discussed; no established clinical enhancement indication.
A gene-therapy trial cannot establish efficacy, exposure or safety for an injected research protein.
Why It's Being Studied
- Muscle disease gene transfer
- Activin and myostatin biology
Mechanism of Action
The processed protein binds activins and modulates myostatin-family signalling; this is broader than selectively increasing muscle.
The processed protein binds activins and modulates myostatin-family signalling; this is broader than selectively increasing muscle. A gene-therapy trial cannot establish efficacy, exposure or safety for an injected research protein.
From molecular target to clinical evidence
Tap each stage to see what happens.
Background: Clinical Peptide Medicines
Clinical peptide medicines include endocrine treatments, antimicrobial drugs, receptor blockers and targeted diagnostic or cancer agents. They do not share one mechanism or one set of indications.
An approval belongs to a specific medicine and indication. A diagnostic tracer, an antibiotic and a hormone are not interchangeable wellness products; read each profile's own mechanism and prescribing source.
Research Areas & Routes Studied
- Muscle disease gene transfer
- Activin and myostatin biology
- Cell and animal research
Evidence Summary
Early human studies concern AAV-mediated gene transfer, not validated administration of commercial follistatin-344 protein.
Higher tiers carry more weight. Filled tiers have evidence for Follistatin-344; tap to read it.
No evidence at this tier is summarised for Follistatin-344. Absence of data is not evidence of safety or benefit.
1 cited sources.
- Narrative review1
Evidence limitations
- Early human studies concern AAV-mediated gene transfer, not validated administration of commercial follistatin-344 protein.
Reported Adverse Events in Research
- Activin, FSH and reproductive effects, broad biological signalling and uncertain product identity are unresolved concerns.
Limitations of Current Evidence
- A gene-therapy trial cannot establish efficacy, exposure or safety for an injected research protein.
- Findings apply to the product, route and population studied; they do not establish benefits or safety for unrelated wellness uses or research-vial products.
How to Read This Research
- Is this a single molecule or a family of medicines?
- Is the use diagnostic, therapeutic or investigational?
- Does the quoted outcome match the exact product, formulation and population?
- Use the compound-specific mechanism above; this diagram describes drug development, not a shared biological pathway.
- Historical approval, present availability and off-label use are distinct questions.
- For radiopharmaceuticals and hospital medicines, specialist handling is part of the treatment context.
- Indication
- The condition and population for which a medicine is approved.
- Antagonist
- A compound that blocks activity at a receptor.
- Radiopharmaceutical
- A medicine containing a radioactive isotope for imaging or treatment.
Compare With Other Compounds
| Follistatin-344 | Trofinetide | |
|---|---|---|
| Evidence grade | D — Preclinical Research | B — Moderate Human Evidence |
| Regulatory status | Research Use Only | FDA Approved for Specific Indication |
| Human data | No | Yes |
| Clinical trials | None identified | Registered trials exist |
| Research routes | Cell and animal research | Oral approved medicine |
| Cited sources | 1 | 2 |
Frequently Asked Questions
Research References
- Narrative review
Follistatin-344 — narrative review