Zomacton

Zomacton is a hormone of the hypothalamic-pituitary system.

Indications Zomactone

It is used in the following conditions:

• children who have growth retardation associated with insufficient secretion of STH;
• children with growth retardation caused by Turner syndrome, which was confirmed by a chromosomal testing procedure.

Release form

The drug is released in the form of a lyophilisate for injection liquid, together with a solvent, in vials with a capacity of 4 and 10 mg.

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Pharmacodynamics

Somatotropin is the active component of the drug, which is a polypeptide similar to human pituitary STH in its structure, amino acid sequence, and pharmacokinetics.

Zomacton causes systemic proportional growth of skeletal bones in a child with a deficiency of pituitary STH, affecting the growth plates of the epiphysis of long bones, as well as bone metabolism. In individuals with a deficiency of STH, as well as osteoporosis, HRT helps to stabilize bone density and mineral structure. The drug activates the processes of collagen binding to chondroitin sulfate and increases the excretion of hydroxyproline. Along with this, an increase in average serum ALP values is also noted.

As a reaction to the use of STH, along with systemic growth, a proportional increase in the size of the skeletal muscles is observed, as well as an increase in the size and number of muscle cells. In addition, the drug leads to an increase in the size of other tissues (epidermis with connective tissues, thymus, liver with increased cell proliferation, and also an insignificant increase in the size of the adrenal glands, sex glands and thyroid gland). HRT using STH did not lead to acceleration of puberty and a disproportionate growth process.

The drug promotes the stimulation of amino acid movement into cells, as well as protein binding. It also reduces cholesterol levels by affecting the lipid and lipoprotein profile. It helps to retain potassium with sodium and phosphorus. Increased renal excretion of calcium is compensated by increased intestinal absorption of this element. The accumulation of these salts shows that there is an increased need for them during tissue growth.

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Pharmacokinetics

The degree of absorption of the STH component with subcutaneous injection is 80%. Plasma Cmax values are recorded after 3-6 hours and are 13-35 ng/ml. Metabolic processes develop inside the liver.

The half-life is 3-4 hours. The excretion of the drug is carried out by the intestines.

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Dosing and administration

Zomacton therapy should be performed under the supervision of a qualified healthcare professional who has experience in treating people with growth hormone deficiency.

The administration schedule and dosage sizes of the medication are selected individually for each patient.

Often such therapy lasts for several years and is determined by the maximum possible medicinal result.

To prevent the occurrence of lipoatrophy in the injection area, injection sites must be changed regularly.

It is necessary to start therapy taking into account the standard recommended dosages.

Deficiency of the secreted element STH.

^{A dosage of 0.17-0.23 mg/kg (equivalent to 4.9-6.9 mg/ m2} of body surface area) is used per week, divided into 6-7 subcutaneous administrations (the daily dose is thus 0.02-0.03 mg/kg (0.7-1 mg/m2 ^of body surface area)). It is prohibited to use a total dose exceeding 0.27 mg/kg (8 mg/m2 ⁾ per week, which corresponds to a daily dose of 0.04 mg/kg.

Turner syndrome.

Over the course of a week, it is necessary to administer 0.33 mg/kg of the substance (approximately 9.86 mg/m2 ^of body surface area), which is divided into 6-7 subcutaneous injections (the daily dosage in this case is equal to 0.05 mg/kg (approximately 1.40-1.63 mg/m2 ⁾ ).

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Use Zomactone during pregnancy

Zomacton should not be prescribed to pregnant women or women of childbearing age who are not using contraceptives.

Clinical trials using drugs containing GH in nursing mothers have not been performed, so there is no information on whether GH is excreted in breast milk.

Contraindications

The drug is contraindicated in case of severe intolerance to STH or its other components. It is also not prescribed to children who have already had closure of the bone epiphyses.

The drug should not be used if the patient has symptoms of active tumor development. Antitumor treatment must be completed before starting therapy with STH; in addition, there should be no signs of tumor growth inside the skull. If symptoms of tumor growth are observed, therapy should be stopped.

It is prohibited to use the drug in people in critical condition, as well as in those who have complications associated with open cardiac surgery, abdominal surgery and multiple injuries, as well as in acute respiratory failure and other similar conditions.

Therapy with STH should be discontinued in children with chronic kidney disease in case of kidney transplantation.

Side effects Zomactone

With subcutaneous injection of the STH substance, atrophy or proliferation of the subcutaneous fat layer may develop, and in addition, bruises and pinpoint hemorrhages may be observed in the injection area. Sometimes people experience itchy erythema or pain at the injection site.

Other side effects include:

• disorders of the lymph and blood system: sometimes anemia appears;
• disorders in the cardiovascular system: sometimes the blood pressure level increases (adults) or tachycardia develops. An isolated increase in blood pressure values is also observed in children;
• damage to the vestibular apparatus with hearing organs: sometimes dizziness occurs;
• problems with the endocrine system: hypothyroidism is often observed;
• manifestations associated with the visual organs: sometimes diplopia or swelling of the disc in the area of the optic nerve appears;
• Gastrointestinal disorders: sometimes nausea, abdominal pain, vomiting or bloating occur. Diarrhea develops occasionally;
• systemic disorders and signs in the injection area: most often in adults, peripheral edema or simply edema occurs (with a lesser frequency they also occur in children) at the injection site, as well as asthenia. Sometimes atrophy in the injection area, a feeling of weakness, hemorrhage in the area of drug administration, as well as hypertrophy are observed;
• immune damage: often there is production of antibodies;
• changes in test results: diseases associated with kidney function are observed sporadically;
• nutritional and metabolic disorders: most often, mild hyperglycemia develops in adults. Less often, glucose tolerance disorder is noted (children). Sometimes hyperphosphatemia or hypoglycemia is recorded. Diabetes mellitus type 2 occurs sporadically;
• lesions of connective tissues, and at the same time, musculoskeletal tissues: myalgia or arthralgia are often observed in adults. Less often, these disorders occur in children. Often, adults may experience stiffness of limb movement (sometimes this also happens in children). Sometimes bone pain, muscle atrophy, and carpal tunnel syndrome appear;
• tumors of various nature: sometimes tumors of malignant or rare nature appear. Leukemia occasionally develops in children;
• problems with the function of the nervous system: paresthesia or headaches often occur in adults. Insomnia or hypertension are also common. Sometimes nystagmus or a feeling of drowsiness appears. Individually, the values of intracranial pressure increase, neuropathy occurs, and also (in children) paresthesia or insomnia;
• mental disorders: personality disorders are sometimes noted;
• lesions of the urinary system and kidneys: sometimes hematuria, urinary incontinence, abnormal urine, polyuria and urinary frequency disorder appear;
• Signs of the mammary glands and genitals: in adults, gynecomastia or genital discharge sometimes appears. Rarely, gynecomastia has been noted in children;
• disorders in the subcutaneous layer and epidermis: sometimes skin hypertrophy or atrophy, lipodystrophy, urticaria, and also hirsutism or exfoliative dermatitis occur.

There are data on the development of pancreatitis during post-registration use of STH (there are no data on the frequency of such cases).

Children taking STH sometimes developed slipped capital femoral epiphysis and Perthes disease. The first disorder mainly develops in disorders associated with the endocrine system, and the second - in the case of short stature. But there is no information on whether these diseases develop more often with the use of STH. With such diagnoses, painful and uncomfortable sensations appear in the hip or knee area.

Other negative signs are considered characteristic of STH - among them are hyperglycemia caused by a decrease in sensitivity to insulin, a decrease in free thyroxine levels, and also an increase in ICP values, which is benign.

There may also be a risk of developing intolerance symptoms.

Overdose

Although there is no information regarding intoxication with Zomacton, acute poisoning may result in an initial form of hypoglycemia, followed by hyperglycemia.

There is no data on the effects of prolonged intoxication. But there is a suggestion that it may cause symptoms similar to those seen in cases of excessive production of human STH (for example, the development of acromegaly).

Interactions with other drugs

Treatment with GCS can slow down the growth stimulation provided by the drug. People with existing ACTH deficiency need to select the replacement dose of GCS very carefully to avoid suppressive effects on STH activity.

Large doses of estrogens with androgens or anabolics can lead to accelerated bone maturation, which results in decreased growth of body length.

Because STH can cause insulin resistance in patients, there is a possibility that diabetics will need to adjust their therapy.

Information that emerged from drug interaction studies in adults with growth hormone deficiency shows that the use of somatotropin may significantly increase the clearance of components that undergo metabolic processes within the P450 3A4 hemoprotein system (including corticosteroids, cyclosporine with sex hormones, and anticonvulsants), causing their plasma levels to decrease. There is no data on the impact of this on the clinical picture.

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Storage conditions

Zomacton should be stored in a place closed to children. Temperature values are in the range of 2-8°C.

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Shelf life

Zomacton can be used for a period of 3 years from the date of production of the therapeutic drug. The diluted liquid must be stored in the refrigerator (temperature is 2-8 ° C), placing the bottle vertically, for up to 28 days.

Analogues

The analogs of the drug are the substances Biorostan, Somatin, Jintropin and Groutropin with Biosome and Rastan, and in addition Genotropin, Humatrop and Nutropin with Norditropin.

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