Somatrogon
Somatrogon is an FDA-approved long-acting growth hormone fusion protein. Somatrogon fuses human growth hormone to three copies of the C-terminal peptide of the human chorionic gonadotropin beta subunit. The added carbohydrate-rich peptide increases hydrodynamic size and sialic acid content, slowing renal filtration and clearance sufficiently for weekly administration while preserving agonism at the growth hormone receptor.
For research use only.
Key Facts
- CAS
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- Molecular Weight (MW)
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- Half-life
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- FDA status
- Approved
- Administration Route
- subcutaneous
- Frequency
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- Last updated
- Aug 30, 2026
- Reviewed
- Aug 30, 2026
Research summary
Long-acting recombinant human growth hormone in which the hormone is fused to three copies of the C-terminal peptide of the chorionic gonadotropin beta subunit. The added glycosylation slows clearance enough for once-weekly rather than daily injection. Marketed as Ngenla and FDA-approved for growth hormone deficiency in children, it is a prescription medicine.
Peptide Library's Somatrogon profile summarises 5 cited studies listed in the Science section, the compound's regulatory status, and research-protocol parameters reported for it. It is a research reference, not medical advice.
Protocol
- Dosage Range
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- Frequency
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- Cycle
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- Administration Route
- subcutaneous
- Reconstitution Guide
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Science
Mechanism of Action
Somatrogon fuses human growth hormone to three copies of the C-terminal peptide of the human chorionic gonadotropin beta subunit. The added carbohydrate-rich peptide increases hydrodynamic size and sialic acid content, slowing renal filtration and clearance sufficiently for weekly administration while preserving agonism at the growth hormone receptor.
Studies
- Efficacy and Safety of Somapacitan Relative to Somatrogon and Lonapegsomatropin in Pediatric Growth Hormone Deficiency: Systematic Literature Review and Network Meta-analysis
- Efficacy and safety of once-weekly somatrogon in adults with growth hormone deficiency: a randomized phase 3 study
- Efficacy and safety of once-weekly somatrogon following up to 4 years of treatment in Japanese children with growth hormone deficiency: results from an open-label extension of a phase 3 study
- Efficacy and Safety of Weekly Somatrogon vs Daily Somatropin in Children With Growth Hormone Deficiency: A Phase 3 Study
- Long-acting growth hormone in the treatment of growth hormone deficiency in children: a systematic literature review and network meta-analysis
Regulatory & research status
Somatrogon is an FDA-approved product for specific labelled indications. Approval does not extend to the research contexts described on this page, and approved products are prescription medicines.
| FDA status | Approved |
|---|---|
| Research status | Approved product (see FDA status) |
| Availability | Prescription-Only |
| WADA (sport) | Unknown / Not Listed |
| Library classification | FDA-Approved |
Benefits
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Potential Side Effects
No side effects listed yet for this entry.
Storage & stability
Lyophilized (freeze-dried) peptide powder is far more stable than the reconstituted solution. Keep sealed vials cold, dry and away from light; long-term storage is typically frozen, with short-term refrigeration for vials in use.
Once reconstituted in bacteriostatic water, keep the solution refrigerated, avoid repeated freeze–thaw cycles and agitation, and label the vial with the reconstitution date and concentration. Discard any solution that turns cloudy or shows particulates.
Degradation rates differ by sequence: peptides containing methionine, cysteine, asparagine or glutamine are more prone to oxidation and deamidation, so shelf life after reconstitution is compound-specific rather than universal.
Read the full guide: how to store peptides before and after reconstitution →
Source: Manning MC, Chou DK, Murphy BM, Payne RW, Katayama DS. Stability of protein pharmaceuticals: an update. Pharm Res. 2010;27(4):544–575. (PMID 20143256). General guidance for research handling; not product-specific instructions.
Somatrogon: frequently asked questions
What is Somatrogon?
Long-acting recombinant human growth hormone in which the hormone is fused to three copies of the C-terminal peptide of the chorionic gonadotropin beta subunit. The added glycosylation slows clearance enough for once-weekly rather than daily injection. Marketed as Ngenla and FDA-approved for growth hormone deficiency in children, it is a prescription medicine.
How does Somatrogon work?
Somatrogon fuses human growth hormone to three copies of the C-terminal peptide of the human chorionic gonadotropin beta subunit. The added carbohydrate-rich peptide increases hydrodynamic size and sialic acid content, slowing renal filtration and clearance sufficiently for weekly administration while preserving agonism at the growth hormone receptor.
Is Somatrogon FDA approved?
Yes. Somatrogon is approved by the FDA, and approved products are prescription medicines. Approval is always for specific indications studied in clinical trials, so an approved status does not mean the compound is approved for every use it is discussed for. Research-chemical material sold under the same name is not the approved product.
What peptides are similar to Somatrogon?
Compounds most often compared with Somatrogon include Human Growth Hormone (Somatropin), Somapacitan, Lonapegsomatropin and Pegvisomant. They are grouped by shared mechanism or research area rather than by equivalence, and their regulatory status and evidence base differ.
References
- Efficacy and Safety of Somapacitan Relative to Somatrogon and Lonapegsomatropin in Pediatric Growth Hormone Deficiency: Systematic Literature Review and Network Meta-analysis — Adv Ther, 2024External reference
- Efficacy and safety of once-weekly somatrogon in adults with growth hormone deficiency: a randomized phase 3 study — Pituitary, 2026External reference
- Efficacy and safety of once-weekly somatrogon following up to 4 years of treatment in Japanese children with growth hormone deficiency: results from an open-label extension of a phase 3 study — Endocr J, 2026External reference
- Efficacy and Safety of Weekly Somatrogon vs Daily Somatropin in Children With Growth Hormone Deficiency: A Phase 3 Study — J Clin Endocrinol Metab, 2022External reference
- Long-acting growth hormone in the treatment of growth hormone deficiency in children: a systematic literature review and network meta-analysis — Sci Rep, 2024External reference
Related research, comparisons & guides
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Compiled by Peptide Library Editorial · Reviewed Aug 30, 2026 · Updated Aug 30, 2026 · Version 1
This Somatrogon profile is compiled from published literature (5 cited studies linked above), public regulatory records and chemical registries. It describes what research reports; it is not medical advice, and nothing here is a dosing recommendation for humans. Peptide Library does not sell peptides. Editorial policy · How profiles are compiled · Report an error
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