Somavert

/ Pfizer

Treatment should be initiated under the supervision of a physician experienced in the treatment of acromegaly.
A loading dose of 80 mg pegvisomant should be administered subcutaneously under medical supervision. Following this, SOMAVERT 10 mg reconstituted in 1 ml of solvent should be administered once daily as a subcutaneous injection.
Dose adjustments should be based on serum IGF-I levels. Serum IGF-I concentrations should be measured every four to six weeks and appropriate dose adjustments made in increments of 5 mg/day in order to maintain the serum IGF-I concentration within the age-adjusted normal range and to maintain an optimal therapeutic response.
Assessment of baseline levels of liver enzymes prior to initiation of this medical product: Prior to the start of pegvisomant, patients should have an assessment of baseline levels of liver tests (LTs) [serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), serum total bilirubin (TBIL), and alkaline phosphatase (ALP)].
The maximum dose should not exceed 30 mg/day..
Paediatric population: 
Pegvisomant is not indicated for children and adolescents under 18 years old.
Elderly: No dose adjustment is required.
Hepatic or renal impairment: The safety and efficacy of pegvisomant in patients with renal or hepatic insufficiency has not been established.
Method of administration: Pegvisomant should be administered by subcutaneous injection.
The site of injection should be rotated daily to help prevent lipohypertrophy.
See prescribing information for full details

Treatment of adult patients with acromegaly who have had an inadequate response to surgery and/or radiation therapy and in whom an appropriate medical treatment with somatostatin analogues did not normalize IGF-I concentrations or was not tolerated.

Hypersensitivity to pegvisomant or any of the excipients.    

Growth hormone-secreting tumours: Growth hormone-secreting pituitary tumours may sometimes expand, causing serious complications (for example, visual field defects). Treatment by pegvisomant does not reduce tumour size. All patients with these tumours should be carefully monitored in order to avoid any eventual progression in tumour size under treatment.
Serum IGF-1 monitoring: Pegvisomant is a potent antagonist of growth hormone action. A growth hormone deficient state may result from administration of this medicinal product, despite the presence of elevated serum growth hormone levels. Serum IGF-I concentrations should be monitored and maintained within the age-adjusted normal range by adjustment of the pegvisomant dose.
ALT or AST elevations: Prior to the start of pegvisomant, patients should have an assessment of baseline levels of liver tests [serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), serum total bilirubin (TBIL), and alkaline phosphatase (ALP)].
Evidence of obstructive biliary tract disease should be ruled out in patients with elevations of ALT and AST or in patients with a prior history of treatment with any somatostatin analogue. Administration of pegvisomant should be discontinued if signs of liver disease persist.
Hypoglycaemia: The study conducted with pegvisomant in diabetic patients treated either by insulin or by oral hypoglycaemic medicinal products revealed the risk of hypoglycaemia in this population. Therefore, in acromegalic patients with diabetes mellitus, doses of insulin or hypoglycaemic medicinal products may need to be decreased.
Improved fertility
The therapeutic benefits of a reduction in IGF-I concentration which results in improvement of the patient’s clinical condition could potentially also improve fertility in female patients.
Pregnancy
Acromegaly control may improve during pregnancy. Pegvisomant is not recommended during pregnancy.  If pegvisomant is used during pregnancy, IGF-I levels should be closely monitored and
pegvisomant doses may need to be adjusted based on IGF-I values.
See prescribing information for full details.

The most commonly reported adverse reactions occurring in ≥ 10% of patients with acromegaly treated with pegvisomant during the clinical trials were headache 25%, arthralgia 16% and diarrhoea 13%.
See prescribing information for full details.

No interaction studies have been performed. It should be considered whether to continue treatment with somatostatin analogues. The use of this medicine in combination with other medicinal products for the treatment of acromegaly has not been extensively investigated.
Patients receiving insulin or oral hypoglycaemic medicinal products may require dose reduction of these active substances due to the effect of pegvisomant on insulin sensitivity.
Pegvisomant has significant structural similarity to growth hormone which causes it to cross-react in commercially available growth hormone assays. Since serum concentrations of therapeutically-effective doses of this medicine are generally 100 to 1000 times higher than the actual serum growth hormone concentrations seen in acromegalics, measurements of serum growth hormone concentrations will be spuriously reported in commercially available growth hormone assays. Pegvisomant treatment should therefore not be monitored or adjusted based on serum growth hormone concentrations reported from these assays.

Pregnancy: ® is not recommended during pregnancy and in women of childbearing potential not using contraception.
If pegvisomant is used during pregnancy, IGF-I levels should be closely monitored, especially during the first trimester. It may be necessary to adjust the dose of pegvisomant during pregnancy. 
Breast-feeding: The excretion of pegvisomant in breast milk has not been studied in animals. Clinical data are too limited (one reported case) to draw any conclusion on the excretion of pegvisomant in human breast milk. Therefore, pegvisomant should not be used in breast-feeding women. However, breast-feeding may be continued if this medicine is discontinued: this decision should take into account the benefit of pegvisomant therapy to the mother and the benefit of breast-feeding to the child.

There is limited experience of overdose with pegvisomant. In the one reported incident of acute overdose, where 80 mg/day was administered for 7 days, the patient experienced a slight increase in fatigue and dry mouth. In the week following discontinuation of treatment the adverse reactions noted were: insomnia, increased fatigue, oedema peripheral, tremor, and weight gain. Two weeks after stopping treatment, leukocytosis and moderate bleeding from injection and vein puncture sites was observed which were considered possibly related to pegvisomant.
In cases of overdose, administration of this medicine should be discontinued and not resumed until IGF-I levels return to within or above the normal range.

Incompatibilities: In the absence of compatibility studies, this medicinal product must not be mixed with other medicinal products.
Shelf life: The expiry date of the product is indicated on the packaging materials. After reconstitution, the product should be used immediately.
Storage: Store in a refrigerator (2°C – 8°C). Do not freeze. Keep the vial in the outer carton in order to protect from light.