Pegvisomant

Pegvisomant selectively binds to growth hormone (GH) receptors on cell surfaces, where it blocks the binding of endogenous GH, and thus interferes with GH signal transduction. Inhibition of GH action results in decreased serum concentrations of IGF-1, as well as other GH-responsive serum proteins such as free IGF-1, the acid-labile subunit of IGF-1 (ALS), and insulin-like growth factor binding protein-3 (IGFBP-3).

• SOMAVERT is indicated for the treatment of acromegaly in patients who have had an inadequate response to surgery or radiation therapy, or for whom these therapies are not appropriate. The goal of treatment is to normalize serum insulin-like growth factor-1 (IGF-1) levels.

• None. None.contraindicated

• Administer a 40 mg loading dose subcutaneously under physician supervision. ( 2.1 ) • After proper injection instruction, on day after loading dose, patients or caregivers begin daily subcutaneous injections of 10 mg. ( 2.1 ) • Adjust dosage in 5 mg increments or decrements until serum IGF-1 concentrations are maintained within age-adjusted normal range. Do not adjust dosage based on growth hormone (GH) levels or signs or symptoms of acromegaly. ( 2.1 ) • Dosage range is 10 mg to 30 mg once daily. ( 2.1 ) • Perform liver tests prior to first dosage and if greater than 3 times upper limit of normal should work-up prior to SOMAVERT administration. ( 2.2 ) • Follow reconstitution and injection procedures. ( 2.3 , 2.4 ) 2.1 Dosage Information The recommended loading dose of SOMAVERT is 40 mg given subcutaneously, under healthcare provider supervision. Provide proper training in subcutaneous injection technique to patients or their caregivers so they can receive once daily subcutaneous injections. On the next day following the loading dose, instruct patients or their caregivers to begin daily subcutaneous injections of 10 mg of SOMAVERT. Titrate the dosage to normalize serum IGF-1 concentrations (serum IGF-1 concentrations should be measured every four to six weeks). The dosage should not be based on growth hormone (GH) concentrations or signs and symptoms of acromegaly. It is unknown whether patients who remain symptomatic while achieving normalized IGF-1 concentrations would benefit from increased SOMAVERT dosage.

• Hypoglycemia : Monitor blood glucose in patients with diabetes mellitus and reduce anti-diabetic drug therapy as necessary. ( 5.1 ) • Liver Toxicity: Should have more frequent liver tests and/or discontinue SOMAVERT. ( 5.2 ) • Systemic Hypersensitivity : Monitor closely when re-initiating SOMAVERT in patients with systemic hypersensitivity. ( 5.5 ) 5.1 Hypoglycemia Associated With GH Lowering in Patients With Diabetes Mellitus GH opposes the effects of insulin on carbohydrate metabolism by decreasing insulin sensitivity; thus, glucose tolerance may improve in some patients treated with SOMAVERT. Patients should be carefully monitored and doses of anti-diabetic drugs reduced as necessary to avoid hypoglycemia in patients with diabetes mellitus. 5.2 Liver Toxicity Baseline serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), serum total bilirubin (TBIL), and alkaline phosphatase (ALP) levels should be obtained prior to initiating therapy with SOMAVERT. Table 1 lists recommendations regarding initiation of treatment with SOMAVERT, based on the results of these liver tests (LTs). Asymptomatic, transient elevations in transaminases up to 15 times ULN have been observed in <2% of subjects among two open-label trials (with a total of 147 patients). These reports were not associated with an increase in bilirubin. Transaminase elevations normalized with time, most often after suspending treatment.

Clinically significant adverse reactions that appear in other section of the labeling include: • Hypoglycemia Associated with GH Lowering in Patients with Diabetes Mellitus [see Warnings and Precautions (5.1) ] • Liver Toxicity [see Warnings and Precautions (5.2) ] • Cross-Reactivity with GH Assays [see Warnings and Precautions (5.3) ] • Lipohypertrophy [see Warnings and Precautions (5.4) ] • Systemic Hypersensitivity [see Warnings and Precautions (5.5) ] Elevations of serum concentrations of ALT and AST greater than ten times the ULN were reported in two patients (0.8%) exposed to SOMAVERT in pre-approval clinical studies. One patient was rechallenged with SOMAVERT, and the recurrence of elevated transaminase levels suggested a probable causal relationship between administration of the drug and the elevation in liver enzymes. A liver biopsy performed on the second patient was consistent with chronic hepatitis of unknown etiology. In both patients, the transaminase elevations normalized after discontinuation of the drug. Elevations in ALT and AST levels were not associated with increased levels of TBIL and ALP, with the exception of two patients with minimal associated increases in ALP levels (i.e., less than 3 times ULN). The transaminase elevations did not appear to be related to the dose of SOMAVERT administered, generally occurred within 4 to 12 weeks of initiation of therapy, and were not associated with any identifiable biochemical, phenotypic, or genetic predictors.

Females and Males of Reproductive Potential: Advise premenopausal females of the potential for an unintended pregnancy. ( 8.3 ) 8.1 Pregnancy Risk Summary Postmarketing reports of SOMAVERT use in pregnant women are insufficient to establish a drug-associated risk for major birth defects, miscarriage or adverse maternal or fetal outcomes. Acromegaly may improve during pregnancy (see Clinical Considerations ) . In animal reproduction studies, fetotoxicity was observed at a dose that was 6 times the maximum recommended human dose based on body surface area following subcutaneous administration of pegvisomant during organogenesis or during the preimplantation period (see Data ) . The estimated background risk of major birth defects and miscarriage for the indicated population is unknown. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2–4% and 15–20%, respectively. Clinical Considerations Disease-associated maternal and/or embryofetal risk Published data from case reports, case series, and a small interventional study in pregnant women with acromegaly have demonstrated that acromegaly may improve or stabilize without treatment during pregnancy, particularly if acromegaly is treated before pregnancy. In rare cases, acromegaly may worsen during pregnancy.

Metabolism

Absorption: Following subcutaneous administration, peak serum pegvisomant concentrations are not generally attained until 33 to 77 hours after administration. The mean extent of absorption of a 20-mg subcutaneous dose was 57%, relative to a 10-mg intravenous dose.

In one reported incident of acute overdose with SOMAVERT during pre-marketing clinical studies, a patient self-administered 80 mg/day (2.7 times the maximum recommended maintenance dosage) for seven days. The patient experienced a slight increase in fatigue, had no other complaints, and demonstrated no significant clinical laboratory abnormalities. In cases of overdose, administration of SOMAVERT should be discontinued and not resumed until IGF-1 levels return to within or above the normal range.

• Mar 25, 2003BLABLA021106Pharmacia

1. 1Off Label Use48612%
2. 2Drug Ineffective43311%
3. 3Headache4029.9%
4. 4Fatigue3859.5%
5. 5Insulin-like Growth Factor Increased3799.3%
6. 6Arthralgia3007.4%
7. 7Product Dose Omission Issue2686.6%
8. 8Injection Site Pain2616.4%
9. 9Diarrhoea2556.3%
10. 10Nausea2315.7%
11. 11Pain2135.2%
12. 12Blood Pressure Increased2055.0%
13. 13Product Use Issue2035.0%
14. 14Needle Issue1994.9%
15. 15Malaise1984.9%

The 10 most recently updated of 41 ClinicalTrials.gov registrations naming Pegvisomant as an intervention. Registration is not evidence of efficacy or safety — reference crosswalk only.

• Study of Growth Hormone Inhibition Using Pegvisomant in Severe Insulin Resistance
  Recruiting · Phase 2 · Interventional · 25 enrolled · National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
  NCT05470504updated 2026-05-12
• Safety and Efficacy of Pegvisomant in Children With Growth Hormone Excess
  Completed · Phase 3 · Interventional · 12 enrolled · Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD)
  NCT03882034updated 2025-11-06
• Effects of Pasireotide Lar Therapy on Bone Metabolism
  Recruiting · Observational · 120 enrolled · Fondazione Policlinico Universitario Agostino Gemelli IRCCS
  NCT07179926updated 2025-09-18
• Korean Regulatory Post Marketing Surveillance for Somavert
  Recruiting · Observational · 100 enrolled · Pfizer
  NCT05131100updated 2025-07-04
• PegvisOMant and the Immune SystEm (PROMISE)
  Completed · Observational · 62 enrolled · University of Roma La Sapienza
  NCT05069324updated 2025-01-16
• The RApid Switch From 1st Generation Somatostatin Analogues to PaSireOtiDe In Acromegaly
  Recruiting · Observational · 100 enrolled · IRCCS San Raffaele
  NCT06597383updated 2024-09-19
• Long Term Use of Somavert (Pegvisomant) For A Regulatory Post Marketing Commitment Plan
  Completed · Observational · 251 enrolled · Pfizer
  NCT00658879updated 2023-09-25
• Growth Hormone as a Model for Reversible Activation of Adipose Tissue Fibrosis
  Unknown · Interventional · 10 enrolled · University of Aarhus
  NCT04998500updated 2023-05-30
• Acromegaly Combination Treatment Study
  Terminated · Interventional · 76 enrolled · Cedars-Sinai Medical Center
  NCT01538966updated 2023-01-04
• Growth Hormone, IGF-1 and Medical Treatment in Acromegaly: Are There Effects on Gut Hormone Physiology and Postprandial Substrate Metabolism?
  Completed · Observational · 21 enrolled · University Hospital, Ghent
  NCT02152124updated 2022-12-29

Frequently asked questions

How does Pegvisomant work?

Pegvisomant selectively binds to growth hormone (GH) receptors on cell surfaces, where it blocks the binding of endogenous GH, and thus interferes with GH signal transduction. Inhibition of GH action results in decreased serum concentrations of IGF-1, as well as other GH-responsive serum proteins such as free IGF-1, the acid-labile subunit of IGF-1 (ALS), and insulin-like growth factor binding protein-3 (IGFBP-3).

What is Pegvisomant used for?

According to FDA labeling, Pegvisomant carries indications including: SOMAVERT is indicated for the treatment of acromegaly in patients who have had an inadequate response to surgery or radiation therapy, or for whom these therapies are not appropriate. The goal of treatment is to normalize serum insulin-like growth factor-1 (IGF-1) levels.. This is a reference summary of labeled uses, not medical advice or a treatment recommendation.

What class of drug is Pegvisomant?

Pegvisomant is classified as Other anterior pituitary lobe hormones and analogues, Growth Hormone Receptor Antagonist, Growth Hormone Receptor Antagonists, Insulin-like Growth Factor-1 Receptor Interactions, Bone Formation Stimulation, Decreased Erythroid Cell Production, Decreased Growth Factor Activity, Decreased Protein Synthesis.

What are the brand names for Pegvisomant?

Pegvisomant is marketed under brand names including Somavert.

What are the contraindications for Pegvisomant?

Pegvisomant labeling lists contraindications including: None. None.. Always consult the full prescribing information and a clinician.