Somavert

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Somavert

Classes

Growth Hormone Receptor Antagonists

Administration
Oral Administration Extemporaneous Compounding-Oral

Visually inspect parenteral products for particulate matter and discoloration prior to administration whenever solution and container permit.

Injectable Administration Subcutaneous Administration

Administer pegvisomant by subcutaneous injection only; avoid intravenous administration.
The loading dose of pegvisomant should be given under physician supervision.
Provide proper training in subcutaneous injection technique to patients or their caregivers so they can receive once daily subcutaneous injections.
 
Loading dose preparation:
Reconstitute 2 vials of pegvisomant each containing 20 mg with supplied diluent [2 vials of lyophilized powder and 2 of the 2.25 mL syringes (each syringe contains 1 mL of diluent - Sterile Water for Injection)].
Remove the first package (1 vial of lyophilized powder containing 20 mg of pegvisomant and one 2.25 mL syringe containing the diluent) from the refrigerator about 10 minutes prior to the planned injection time.
Reconstitute the first 20 mg vial with diluent. When using the diluent in the 2.25 mL syringe, inject the contents of the syringe slowly onto the sides of the vial. Do not inject the diluent directly on the powder.
Slowly swirl the solution to ensure that all of the lyophilized powder has gone into solution. If foaming is seen, the solution is likely damaged and therefore inappropriate to inject. Do not invert the vial or shake the solution.
Visually inspect the reconstituted solution for particulate matter and discoloration prior to administration. The reconstituted solution should be clear. If the solution is cloudy, do not use it.
Once reconstituted, the solution will contain 20 mg/mL of pegvisomant. Withdraw 1 mL reconstituted pegvisomant solution and administer within 6 hours of reconstitution.
Repeat steps to reconstitute the second 20 mg dose.
 
Subcutaneous administration of loading dose:
Inject the first reconstituted pegvisomant solution (20 mg/mL) subcutaneously into the patient's upper arm, upper thigh, abdomen, or buttocks using a 90-degree angle.
Inject the second dose of 20 mg into a different site.
 
Reconstitution/Dilution of daily maintenance doses:
Remove the vial dose (containing 10, 15, 20, 25 or 30 mg of pegvisomant), as well as the 2.25 mL syringe (each syringe contains 1 mL of diluent - Sterile Water for Injection) from the refrigerator about 10 minutes prior to administration time.
Reconstitute by injecting 1 mL of the diluent provided (Sterile Water for Injection) into the vial, aiming the stream of diluent against the glass wall of the vial. Do not directly inject the diluent onto the vial powder.
Do not invert or shake the vial as denaturation of the pegvisomant may occur.
Slowly swirl the solution to ensure that all of the lyophilized powder has gone into solution. If foaming is seen, the solution is likely damaged and therefore inappropriate to inject.
The reconstituted solution should be clear and colorless.
Withdraw the dose (1 mL reconstituted solution) from the vial. The solution must be administered within 6 hours of reconstitution.
 
Subcutaneous administration of daily maintenance doses:
Inject the reconstituted pegvisomant solution subcutaneously into the patient's upper arm, upper thigh, abdomen, or buttocks using a 90-degree angle.

Adverse Reactions
Severe

laryngospasm / Rapid / Incidence not known
anaphylactoid reactions / Rapid / Incidence not known
angioedema / Rapid / Incidence not known

Moderate

antibody formation / Delayed / 17.0-17.0
elevated hepatic enzymes / Delayed / 1.2-12.0
chest pain (unspecified) / Early / 4.0-8.0
hypertension / Early / 8.0-8.0
peripheral edema / Delayed / 4.0-8.0
lipodystrophy / Delayed / 0.5-1.3
jaundice / Delayed / Incidence not known
hepatitis / Delayed / Incidence not known
erythema / Early / Incidence not known

Mild

infection / Delayed / 4.0-23.0
diarrhea / Early / 4.0-14.0
nausea / Early / 8.0-14.0
injection site reaction / Rapid / 4.0-11.0
dizziness / Early / 4.0-8.0
back pain / Delayed / 4.0-8.0
sinusitis / Delayed / 4.0-8.0
paresthesias / Delayed / 7.0-7.0
rash / Early / Incidence not known
urticaria / Rapid / Incidence not known
pruritus / Rapid / Incidence not known
weight gain / Delayed / Incidence not known

Common Brand Names

Somavert

Dea Class

Rx

Description

Growth hormone receptor antagonist, given subcutaneously
Used for treatment of acromegaly
Established efficacy and tolerability profile

Dosage And Indications
For the treatment of acromegaly in patients who have had an inadequate response to surgery and/or radiation therapy and/or other medical therapies, or for whom these therapies are not appropriate. Subcutaneous dosage Adults

40 mg subcutaneously loading dose, followed by 10 mg subcutaneously once daily. Adjust dose in 5-mg increments, up to 30 mg per day, based on serum IGF-I concentrations.

Dosing Considerations
Hepatic Impairment

Patients with transaminases more than 3 times the upper limit of normal (ULN), should not receive pegvisomant until a comprehensive workup establishes the cause of the patient's liver dysfunction. Monitor closely if treatment is initiated. If hepatotoxicity occurs during treatment in any patient, drug cessation may be required. Monitor liver function tests (LFTs) concentrations before pegvisomant initiation and periodically during drug receipt.

Renal Impairment

Specific guidelines for dosage adjustments in renal impairment are not available; it appears that no dosage adjustments are needed.

Drug Interactions

Acarbose: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Acetaminophen; Caffeine; Dihydrocodeine: (Moderate) In clinical trials, patients taking opiate agonists often required higher serum pegvisomant concentrations to achieve appropriate IGF-I suppression compared with patients not receiving opiate agonists. The mechanism of this interaction is unknown.
Acetaminophen; Codeine: (Moderate) In clinical trials, patients taking opiate agonists often required higher serum pegvisomant concentrations to achieve appropriate IGF-I suppression compared with patients not receiving opiate agonists. The mechanism of this interaction is unknown.
Acetaminophen; Hydrocodone: (Moderate) In clinical trials, patients taking opiate agonists often required higher serum pegvisomant concentrations to achieve appropriate IGF-I suppression compared with patients not receiving opiate agonists. The mechanism of this interaction is unknown.
Acetaminophen; Oxycodone: (Moderate) In clinical trials, patients taking opiate agonists often required higher serum pegvisomant concentrations to achieve appropriate IGF-I suppression compared with patients not receiving opiate agonists. The mechanism of this interaction is unknown.
Alfentanil: (Moderate) In clinical trials, patients taking opiate agonists often required higher serum pegvisomant concentrations to achieve appropriate IGF-I suppression compared with patients not receiving opiate agonists. The mechanism of this interaction is unknown.
Alogliptin: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Alogliptin; Metformin: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Alogliptin; Pioglitazone: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Antidiabetic Agents: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Aspirin, ASA; Carisoprodol; Codeine: (Moderate) In clinical trials, patients taking opiate agonists often required higher serum pegvisomant concentrations to achieve appropriate IGF-I suppression compared with patients not receiving opiate agonists. The mechanism of this interaction is unknown.
Aspirin, ASA; Oxycodone: (Moderate) In clinical trials, patients taking opiate agonists often required higher serum pegvisomant concentrations to achieve appropriate IGF-I suppression compared with patients not receiving opiate agonists. The mechanism of this interaction is unknown.
Atropine; Difenoxin: (Moderate) Diphenoxylate/difenoxin is a synthetic opiate agonist with a chemical structure similar to that of meperidine. In clinical trials, patients taking opiate agonists often required higher serum pegvisomant concentrations to achieve appropriate IGF-I suppression compared with patients not receiving opiate agonists. The mechanism of this interaction is unknown.
Belladonna; Opium: (Moderate) In clinical trials, patients taking opiate agonists often required higher serum pegvisomant concentrations to achieve appropriate IGF-I suppression compared with patients not receiving opiate agonists. The mechanism of this interaction is unknown.
Benzhydrocodone; Acetaminophen: (Moderate) In clinical trials, patients taking opiate agonists often required higher serum pegvisomant concentrations to achieve appropriate IGF-I suppression compared with patients not receiving opiate agonists. The mechanism of this interaction is unknown.
Bromocriptine: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Butalbital; Acetaminophen; Caffeine; Codeine: (Moderate) In clinical trials, patients taking opiate agonists often required higher serum pegvisomant concentrations to achieve appropriate IGF-I suppression compared with patients not receiving opiate agonists. The mechanism of this interaction is unknown.
Butalbital; Aspirin; Caffeine; Codeine: (Moderate) In clinical trials, patients taking opiate agonists often required higher serum pegvisomant concentrations to achieve appropriate IGF-I suppression compared with patients not receiving opiate agonists. The mechanism of this interaction is unknown.
Canagliflozin: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Canagliflozin; Metformin: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Celecoxib; Tramadol: (Moderate) In clinical trials, patients taking opiate agonists often required higher serum pegvisomant concentrations to achieve appropriate IGF-I suppression compared with patients not receiving opiate agonists. The mechanism of this interaction is unknown.
Chlorpheniramine; Codeine: (Moderate) In clinical trials, patients taking opiate agonists often required higher serum pegvisomant concentrations to achieve appropriate IGF-I suppression compared with patients not receiving opiate agonists. The mechanism of this interaction is unknown.
Chlorpheniramine; Dihydrocodeine; Phenylephrine: (Moderate) In clinical trials, patients taking opiate agonists often required higher serum pegvisomant concentrations to achieve appropriate IGF-I suppression compared with patients not receiving opiate agonists. The mechanism of this interaction is unknown.
Chlorpheniramine; Hydrocodone: (Moderate) In clinical trials, patients taking opiate agonists often required higher serum pegvisomant concentrations to achieve appropriate IGF-I suppression compared with patients not receiving opiate agonists. The mechanism of this interaction is unknown.
Chlorpropamide: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Codeine: (Moderate) In clinical trials, patients taking opiate agonists often required higher serum pegvisomant concentrations to achieve appropriate IGF-I suppression compared with patients not receiving opiate agonists. The mechanism of this interaction is unknown.
Codeine; Guaifenesin: (Moderate) In clinical trials, patients taking opiate agonists often required higher serum pegvisomant concentrations to achieve appropriate IGF-I suppression compared with patients not receiving opiate agonists. The mechanism of this interaction is unknown.
Codeine; Guaifenesin; Pseudoephedrine: (Moderate) In clinical trials, patients taking opiate agonists often required higher serum pegvisomant concentrations to achieve appropriate IGF-I suppression compared with patients not receiving opiate agonists. The mechanism of this interaction is unknown.
Codeine; Phenylephrine; Promethazine: (Moderate) In clinical trials, patients taking opiate agonists often required higher serum pegvisomant concentrations to achieve appropriate IGF-I suppression compared with patients not receiving opiate agonists. The mechanism of this interaction is unknown.
Codeine; Promethazine: (Moderate) In clinical trials, patients taking opiate agonists often required higher serum pegvisomant concentrations to achieve appropriate IGF-I suppression compared with patients not receiving opiate agonists. The mechanism of this interaction is unknown.
Dapagliflozin: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Dapagliflozin; Metformin: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Dapagliflozin; Saxagliptin: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Diphenoxylate; Atropine: (Moderate) Diphenoxylate/difenoxin is a synthetic opiate agonist with a chemical structure similar to that of meperidine. In clinical trials, patients taking opiate agonists often required higher serum pegvisomant concentrations to achieve appropriate IGF-I suppression compared with patients not receiving opiate agonists. The mechanism of this interaction is unknown.
Dulaglutide: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Empagliflozin: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Empagliflozin; Linagliptin: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Empagliflozin; Linagliptin; Metformin: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Empagliflozin; Metformin: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Ertugliflozin: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Ertugliflozin; Metformin: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Ertugliflozin; Sitagliptin: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Exenatide: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Fentanyl: (Moderate) In clinical trials, patients taking opiate agonists often required higher serum pegvisomant concentrations to achieve appropriate IGF-I suppression compared with patients not receiving opiate agonists. The mechanism of this interaction is unknown.
Glimepiride: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Glipizide: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Glipizide; Metformin: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Glyburide: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Glyburide; Metformin: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Guaifenesin; Hydrocodone: (Moderate) In clinical trials, patients taking opiate agonists often required higher serum pegvisomant concentrations to achieve appropriate IGF-I suppression compared with patients not receiving opiate agonists. The mechanism of this interaction is unknown.
Homatropine; Hydrocodone: (Moderate) In clinical trials, patients taking opiate agonists often required higher serum pegvisomant concentrations to achieve appropriate IGF-I suppression compared with patients not receiving opiate agonists. The mechanism of this interaction is unknown.
Hydrocodone: (Moderate) In clinical trials, patients taking opiate agonists often required higher serum pegvisomant concentrations to achieve appropriate IGF-I suppression compared with patients not receiving opiate agonists. The mechanism of this interaction is unknown.
Hydrocodone; Ibuprofen: (Moderate) In clinical trials, patients taking opiate agonists often required higher serum pegvisomant concentrations to achieve appropriate IGF-I suppression compared with patients not receiving opiate agonists. The mechanism of this interaction is unknown.
Hydrocodone; Pseudoephedrine: (Moderate) In clinical trials, patients taking opiate agonists often required higher serum pegvisomant concentrations to achieve appropriate IGF-I suppression compared with patients not receiving opiate agonists. The mechanism of this interaction is unknown.
Hydromorphone: (Moderate) In clinical trials, patients taking opiate agonists often required higher serum pegvisomant concentrations to achieve appropriate IGF-I suppression compared with patients not receiving opiate agonists. The mechanism of this interaction is unknown.
Ibuprofen; Oxycodone: (Moderate) In clinical trials, patients taking opiate agonists often required higher serum pegvisomant concentrations to achieve appropriate IGF-I suppression compared with patients not receiving opiate agonists. The mechanism of this interaction is unknown.
Insulin Aspart: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Insulin Aspart; Insulin Aspart Protamine: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Insulin Degludec; Liraglutide: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Insulin Detemir: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Insulin Glargine: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Insulin Glargine; Lixisenatide: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Insulin Glulisine: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Insulin Lispro: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Insulin Lispro; Insulin Lispro Protamine: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Insulin, Inhaled: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Isophane Insulin (NPH): (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Levorphanol: (Moderate) In clinical trials, patients taking opiate agonists often required higher serum pegvisomant concentrations to achieve appropriate IGF-I suppression compared with patients not receiving opiate agonists. The mechanism of this interaction is unknown.
Linagliptin: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Linagliptin; Metformin: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Liraglutide: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Lixisenatide: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Mecasermin, Recombinant, rh-IGF-1: (Major) Pegvisomant is a growth hormone receptor antagonist used in the treatment of acromegaly; administration results in a significant decrease of endogenous serum IGF-1 levels. Use caution if coadministering mecasermin and pegvisomant.
Meperidine: (Moderate) In clinical trials, patients taking opiate agonists often required higher serum pegvisomant concentrations to achieve appropriate IGF-I suppression compared with patients not receiving opiate agonists. The mechanism of this interaction is unknown.
Metformin: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Metformin; Repaglinide: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Metformin; Rosiglitazone: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Metformin; Saxagliptin: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Metformin; Sitagliptin: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Methadone: (Moderate) In clinical trials, patients taking opiate agonists often required higher serum pegvisomant concentrations to achieve appropriate IGF-I suppression compared with patients not receiving opiate agonists. The mechanism of this interaction is unknown.
Miglitol: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Morphine: (Moderate) In clinical trials, patients taking opiate agonists often required higher serum pegvisomant concentrations to achieve appropriate IGF-I suppression compared with patients not receiving opiate agonists. The mechanism of this interaction is unknown.
Morphine; Naltrexone: (Moderate) In clinical trials, patients taking opiate agonists often required higher serum pegvisomant concentrations to achieve appropriate IGF-I suppression compared with patients not receiving opiate agonists. The mechanism of this interaction is unknown.
Nateglinide: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Oliceridine: (Moderate) In clinical trials, patients taking opiate agonists often required higher serum pegvisomant concentrations to achieve appropriate IGF-I suppression compared with patients not receiving opiate agonists. The mechanism of this interaction is unknown.
Opiate Agonists: (Moderate) In clinical trials, patients taking opiate agonists often required higher serum pegvisomant concentrations to achieve appropriate IGF-I suppression compared with patients not receiving opiate agonists. The mechanism of this interaction is unknown.
Oxycodone: (Moderate) In clinical trials, patients taking opiate agonists often required higher serum pegvisomant concentrations to achieve appropriate IGF-I suppression compared with patients not receiving opiate agonists. The mechanism of this interaction is unknown.
Oxymorphone: (Moderate) In clinical trials, patients taking opiate agonists often required higher serum pegvisomant concentrations to achieve appropriate IGF-I suppression compared with patients not receiving opiate agonists. The mechanism of this interaction is unknown.
Pioglitazone: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Pioglitazone; Glimepiride: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Pioglitazone; Metformin: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Pramlintide: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Regular Insulin: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Regular Insulin; Isophane Insulin (NPH): (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Remifentanil: (Moderate) In clinical trials, patients taking opiate agonists often required higher serum pegvisomant concentrations to achieve appropriate IGF-I suppression compared with patients not receiving opiate agonists. The mechanism of this interaction is unknown.
Repaglinide: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Rosiglitazone: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Saxagliptin: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Semaglutide: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Sitagliptin: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Sufentanil: (Moderate) In clinical trials, patients taking opiate agonists often required higher serum pegvisomant concentrations to achieve appropriate IGF-I suppression compared with patients not receiving opiate agonists. The mechanism of this interaction is unknown.
Tapentadol: (Moderate) In clinical trials, patients taking opiate agonists often required higher serum pegvisomant concentrations to achieve appropriate IGF-I suppression compared with patients not receiving opiate agonists. The mechanism of this interaction is unknown.
Tolazamide: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Tolbutamide: (Moderate) Monitor blood glucose levels regularly in patients with diabetes, especially when pegvisomant treatment is initiated or when the dose is altered. Adjust treatment with antidiabetic agents as clinically indicated. Pegvisomant increases sensitivity to insulin by lowering the activity of growth hormone, and in some patients glucose tolerance improves with treatment. Patients with diabetes treated with pegvisomant and antidiabetic agents may be more likely to experience hypoglycemia.
Tramadol: (Moderate) In clinical trials, patients taking opiate agonists often required higher serum pegvisomant concentrations to achieve appropriate IGF-I suppression compared with patients not receiving opiate agonists. The mechanism of this interaction is unknown.
Tramadol; Acetaminophen: (Moderate) In clinical trials, patients taking opiate agonists often required higher serum pegvisomant concentrations to achieve appropriate IGF-I suppression compared with patients not receiving opiate agonists. The mechanism of this interaction is unknown.

How Supplied

Somavert/Somavert Kit Subcutaneous Pwd F/Recon: 10mg, 15mg, 20mg, 25mg, 30mg

Maximum Dosage
Adults

40 mg loading dose; 30 mg/day during maintenance therapy.

Elderly

40 mg loading dose; 30 mg/day during maintenance therapy.

Adolescents

Safety and efficacy have not been established.

Children

Safety and efficacy have not been established.

Mechanism Of Action

Pegvisomant is an analogue of human growth hormone that functions as a growth hormone receptor antagonist. In order for growth hormone (GH) to function properly, the GH molecule binds to two adjacent GH receptors, resulting in dimerization of the two receptors and then receptor activation. The most important result of this activation is the stimulation of the production of insulin-like growth factor-I (IGF-I), which mediates most of the actions of GH. As an analogue of GH, pegvisomant has nine mutations that increase its affinity for one of the binding sites on the GH receptor and abolishes the second binding site, thereby preventing functionally correct dimerization of the receptor. Pegvisomant is a highly selective ligand for the GH receptor, and it is not known to cross react with other receptors. After pegvisomant binds to the GH receptor a decreased production of IGF-I by the liver and other tissues is seen. As serum IGF-I levels return to normal patients should experience a decrease in the physical signs and symptoms of acromegaly, including soft-tissue swelling, arthralgia, excessive perspiration, and fatigue.

Pharmacokinetics

Pegvisomant is administered as a subcutaneous injection. Pegvisomant's route of elimination has not been studied in humans; less than 1% of administered drug is recovered in the urine over 96 hours. The rate of clearance is reduced by covalently bound polyethylene glycol (PEG) polymers in the pegvisomant molecule. Following multiple doses, the clearance of pegvisomant is lower than seen following a single dose. The mean total body systemic clearance following multiple doses is estimated to range between 28 to 36 mL/hour for subcutaneous doses ranging from 10 to 20 mg/day, respectively. Pegvisomant is eliminated from serum with a mean half-life of approximately 6 days following both single and multiple doses. Clearance of pegvisomant increases with body weight.
 
Seventy-five percent of patients reach the maximal reduction in serum IGF-I within 2 weeks after initiation of therapy that is sustained throughout treatment. Other patients, however, may not reach maximal reductions in IGF-I levels until 12 to 14 weeks of therapy.

Subcutaneous Route

Peak serum concentrations of pegvisomant are generally not attained until 33 to 77 hours after subcutaneous administration. Relative to a 10 mg intravenous dose, the mean extent of absorption of a 20 mg subcutaneous dose is 57%. The relative bioavailability of 1 injection of 30 mg pegvisomant was compared to 2 injections of 15 mg pegvisomant in a single dose study. The AUC and Cmax of pegvisomant when administered as a single-daily injection of 30 mg was approximately 6% and 4% greater, respectively, as compared to when administered as 2 injections of 15 mg. Pegvisomant does not distribute extensively into tissues, suggested by the mean apparent volume of distribution of 7 liters. Following a single subcutaneous administration, the Cmax and AUC increase disproportionately as the dose increases; mean serum pegvisomant concentrations after 12 weeks of therapy with daily doses of 10, 15, and 20 mg were 6,600, 16,000, and 27,000 ng/mL, respectively.

Pregnancy And Lactation
Pregnancy

There are no adequate, well controlled studies of pegvisomant use in pregnant women. Animal reproduction studies showed no evidence of teratogenic effects associated with pegvisomant treatment during organogenesis. There was a slight increase in post-implantation loss observed when pegvisomant was administered to rabbits at a dose equivalent to 6-times the maximum human dose. As animal reproduction studies are not always predictive of human response, pegvisomant should only be used during pregnancy if clearly needed.[47259]

It is not known if pegvisomant is excreted into human breast milk. Because many drugs are excreted in human milk, breast-feeding mothers should receive pegvisomant therapy cautiously.