Peptide LibraryPegvisomant
Pegvisomant is an FDA-approved growth hormone receptor antagonist. Pegvisomant carries mutations that preserve binding at growth hormone receptor site 1 while disrupting site 2, so it occupies the receptor but cannot drive the functional dimerisation required for signalling. Blocking receptor activation lowers hepatic IGF-1 production.
For research use only.
Key Facts
- CAS
- —
- Molecular Weight (MW)
- —
- Half-life
- Mean half-life estimates of 60 to 138 hours after single or multiple doses (Somavert label)
- FDA status
- Approved
- Evidence level
- FDA Approved
- Human dose established
- Yes
- Administration Route
- Subcutaneous
- Frequency
- Once daily, after a single loading dose
- Last updated
- Nov 7, 2026
- Reviewed
- Nov 7, 2026
Research summary
PEGylated growth hormone analog approved for acromegaly in patients with inadequate response to surgery, radiotherapy, or other medical therapy. It is a receptor antagonist rather than an agonist.
Research evidence
- Regulatory review (FDA label)1 reviewed source
- Controlled human trialsNone in reviewed sources
- Early or uncontrolled human studiesNone in reviewed sources
- Lab & animal studiesNone in reviewed sources
How it works
Each step shows whether the sources Peptide Library has reviewed include that kind of research. Counts are reviewed sources, not every study ever published. Reviews and programme summaries that describe human use are shown as "reported", not as trials, and registered trials without published results are listed but not counted. A higher step means research has progressed further; it does not mean a compound works better or is safer. Compounds whose evidence has not been reviewed yet show "Not reviewed" instead of a guess.
Peptide Library's Pegvisomant 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.
Pegvisomant dosage evidence
Pegvisomant has an FDA-approved human dosage as Somavert, for acromegaly when surgery or radiation have not worked well enough or are not appropriate. The label gives a 40 mg subcutaneous loading dose under supervision, then 10 mg once daily from the next day, adjusted in 5 mg steps every 4–6 weeks to keep serum IGF-1 in the normal range, within 10–30 mg once daily.
| Human dosing established | Yes |
|---|---|
| Studied dose range | 10–30 mg once daily after a 40 mg loading dose |
| Route | Subcutaneous |
| Frequency | Once daily, after a single loading dose |
| Duration studied | Continuous |
| Titration | Measure serum IGF-1 every 4–6 weeks; raise the dose by 5 mg if IGF-1 is high and lower it by 5 mg if IGF-1 is below normal, within 10–30 mg once daily. The label says not to adjust the dose by growth hormone levels or symptoms. |
| Half-life | Mean half-life estimates of 60 to 138 hours after single or multiple doses (Somavert label) |
| Evidence level | FDA Approved |
| Last reviewed | 2026-11-07 |
Research-reported dosing
Doses as studied, one row per regimen. Different trials used different regimens; they are listed separately rather than averaged.
| Study / context | Population | Dose | Route | Frequency | Duration | Outcome studied | Source |
|---|---|---|---|---|---|---|---|
| FDA label — Somavert, acromegalyFDA-approved label · FDA prescribing information | Adults with acromegaly who had an inadequate response to surgery or radiation, or for whom these are not appropriate | 40 mg loading dose, then 10 mg daily; range 10–30 mg, maximum 30 mg daily | Subcutaneous, upper arm, upper thigh, abdomen or buttocks | Once daily | Continuous; titrated against serum IGF-1 | In the label's 12-week placebo-controlled study (112 patients), mean IGF-1 fell by 27%, 48% and 63% with 10, 15 and 20 mg/day, against 4% with placebo | SOMAVERT (pegvisomant) for injection — FDA prescribing information, DailyMed |
Where sources disagree
- Pegvisomant blocks the growth hormone receptor. It lowers IGF-1 rather than raising it, so it works in the opposite direction to growth hormone products.
- The label asks for liver tests before starting and lists liver toxicity as a warning. It also warns that glucose tolerance may improve, so people with diabetes may need lower doses of their diabetes medicines to avoid hypoglycaemia.
- Somavert comes as single-dose vials of powder (10, 15, 20, 25 or 30 mg) packed with a prefilled syringe of 1 mL sterile water; each vial is reconstituted with that syringe and used immediately. The label says not to shake the vial.
Science
Mechanism of Action
Pegvisomant carries mutations that preserve binding at growth hormone receptor site 1 while disrupting site 2, so it occupies the receptor but cannot drive the functional dimerisation required for signalling. Blocking receptor activation lowers hepatic IGF-1 production. Because it acts downstream of the pituitary, circulating growth hormone concentrations are not reduced and IGF-1 rather than GH is used to monitor response.
Studies
Research statistics
549 PubMed publications · 52.1% human clinical research · 34 registered trials
Counts of published research through 2026-11-01, not evidence that it works. Publications by year, study types and trials · How publications are counted
Regulatory & research status
Pegvisomant 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 |
How FDA approval, compounding and research-only status differ
Benefits
—
Pegvisomant side effects
No side effects listed yet for this entry.
Storage & stability
This compound is not supplied as a powder to be mixed, so the freeze-dried powder and reconstitution handling described for research peptides does not apply. Storage conditions are product-specific: follow the label or packaging of the product itself.
Pegvisomant: frequently asked questions
What is Pegvisomant?
PEGylated growth hormone analog approved for acromegaly in patients with inadequate response to surgery, radiotherapy, or other medical therapy. It is a receptor antagonist rather than an agonist.
How does Pegvisomant work?
Pegvisomant carries mutations that preserve binding at growth hormone receptor site 1 while disrupting site 2, so it occupies the receptor but cannot drive the functional dimerisation required for signalling. Blocking receptor activation lowers hepatic IGF-1 production.
Is Pegvisomant FDA approved?
Yes. Pegvisomant 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 Pegvisomant?
Compounds most often compared with Pegvisomant include Human Growth Hormone (Somatropin), Somapacitan, Lonapegsomatropin and Somatrogon. They are grouped by shared mechanism or research area rather than by equivalence, and their regulatory status and evidence base differ.
References
- [Pegvisomant in the treatment of acromegaly] — Vnitr Lek, 2022External reference
- Pegvisomant for acromegaly — Aust Prescr, 2017External reference
- Pegvisomant, 2006External reference
- Pegvisomant Pfizer/Sensus — Curr Opin Investig Drugs, 2004External reference
- Pegvisomant: structure and function — J Mol Endocrinol, 2002External reference
Related research, comparisons & guides
Related peptides
Compiled by Peptide Library Editorial · Reviewed Aug 30, 2026 · Updated Nov 7, 2026 · Version 2
This Pegvisomant 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
Track Pegvisomant research, inventory and reconstitution in the free Peptide Library app. Get the app for iOS or Android →