Genotropin

Genotropin is a somatotropin drug – a substance synthesized using specific recombinant technologies, similar to the growth hormone contained in the human body.

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Indications Genotropin

It is used in children in the following cases:

• growth problems caused by insufficient secretion of the growth hormone element by the body;
• growth disorders when a child has Turner syndrome;
• growth problems in a child with chronic kidney failure;
• growth retardation that occurred during the intrauterine period;
• people with Prader-Willi syndrome.

For adults, the drug is prescribed for diagnosed somatotropin deficiency.

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Release form

The drug is released in the form of a lyophilisate with a solvent for injection liquid.

1 pre-filled pen with a capacity of 5.3 mg contains 1 cartridge with 2 chambers (the front one contains lyophilisate, and the back one contains solvent). There is 1 such pen inside the box.

Also, such a pen can have a volume of 12 mg. Pens with such a capacity are packed in packs of 1 or 5 pieces.

Pharmacodynamics

In children with insufficient endogenous somatropin, as well as those suffering from Prader-Willi syndrome, the drug potentiates linear skeletal growth and increases its speed.

In both adults and children, the drug maintains a healthy body structure, promoting muscle growth and fat mobilization. The most sensitive to STH is adipose tissue of the visceral type.

In addition to stimulating lipolysis processes, the substance reduces the volume of triglycerides passing into fat depots. The STH component increases the indicators of IRF-1 substances, and in addition, IRFSB-3 in the blood serum.

Along with this, the drug affects the processes of carbohydrate, and in addition, fat and water-electrolyte metabolism. STH helps stimulate liver endings to LDL, and also affects the lipoprotein and lipid profiles inside the serum.

In general, the use of the drug in people with somatropin deficiency allows to reduce the LDL levels, as well as apolipoprotein B in the blood serum. Along with this, a decrease in the values of total cholesterol can be noted.

Somatotropin increases insulin levels, but fasting sugar levels often remain the same. A child with hypopituitarism may experience fasting hypoglycemia, which disappears when using the drug.

The medication restores the volume of tissue fluids with plasma, which decreases in the case of STH deficiency, and in addition helps to retain potassium with sodium and phosphorus.

The drug stimulates bone metabolism activity. In people with somatotropin deficiency, as well as osteoporosis, with long-term therapy using STH, restoration of bone density with mineral structure is noted.

The use of the drug potentiates physical endurance and muscle strength.

At the same time, STH increases the volume of cardiac output, but the structure of this effect has not yet been determined. A certain role in this process may be played by the deterioration of the resistance of peripheral vessels.

People with a deficiency of the STH component may experience a weakening of mental characteristics, and in addition, a change in mental state. The substance increases vitality, helps improve memory, and in addition affects the level of brain neural mediators.

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Pharmacokinetics

Suction.

The bioavailability values of STH administered subcutaneously are approximately 80% (both in volunteers and in patients with somatotropin deficiency). After subcutaneous administration of a 0.035 mg/kg portion, the Cmax values in blood plasma are within 13-35 ng/ml. It takes 3-6 hours to reach this level.

Excretion.

The half-life of the substance after intravenous injection in people with STH deficiency is about 0.4 hours. However, with subcutaneous administration, this period can increase to 2-3 hours. The noted difference may be associated with slow absorption from the injection site with subcutaneous injections.

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Dosing and administration

The dosage of the medicinal substance and the mode of use are determined individually for each child. The injection is performed subcutaneously, and for each new procedure the injection site should be changed to avoid the development of lipoatrophy.

Growth disorder due to a lack of secreted growth hormone in a child.

The dosage often suggested is 0.025-0.035 mg/kg or 0.7-1.0 mg/ ^m2 per day. There are also data on the use of drugs in higher doses.

If signs of GHD persist into adolescence, therapy should be continued until full somatic development (bone mass indices and body composition) is achieved. It is necessary to monitor the process of achieving the desired peak bone mass values, defined as the value of the T>-1 mark (standardized to the average peak bone mass level in an adult, measured using 2-energy X-ray absorptiometry, which takes into account the ethnicity and gender of the person). This is one of the main therapeutic goals during the transition period.

Treatment regimens for adults.

The initial dosage for an adult with STH deficiency is 0.15-0.3 mg (approximately 0.45-0.9 IU) per day. The maintenance dose is selected separately, taking into account the patient's gender and age; it only rarely exceeds 1.3 mg (4 IU) per day.

It should be taken into account that a woman may need a higher dose than a man. Since healthy physiological production of somatotropin decreases with age, the dose of the drug can be reduced in relation to age.

Clinical and negative symptoms and serum IGF-1 levels can be used as a guide when selecting portion sizes.

The medicine in a dose of 5.3 mg (16 IU) and 12 mg (36 IU) is administered subcutaneously using injector pens - No. 5.3 and No. 12, respectively. After inserting the cartridge into the injector, the process of dilution of the medicine is carried out automatically. Shaking the solution is prohibited at this time.

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Use Genotropin during pregnancy

The amount of clinical data on the use of Genotropin in pregnant women is limited. Therefore, during this period it is necessary to carefully assess the need for the use of the drug and the existing risks.

When pregnancy is normal, pituitary somatotropin levels decrease significantly after week 20, being almost completely replaced by placental somatotropin by week 30. Because of this, the need for replacement therapy with Genotropin in the 3rd trimester is considered low.

Contraindications

Main contraindications:

• the presence of signs of tumor growth, including uncontrolled growth of intracranial neoplasms that are benign in nature (antitumor treatment must be completed before starting to use Genotropin);
• critical pathological conditions in acute form that arise in patients due to surgical procedures inside the peritoneum or on the open heart, and in addition to this, provoked by injuries of a multiple nature and respiratory failure in the acute stage;
• severe obesity (with a weight/height ratio of more than 200%) or severe forms of respiratory disorders in people suffering from Prader-Willi syndrome;
• closure of epiphyseal growth areas in the area of tubular bones;
• the presence of intolerance to any element of the drug.

Caution is required when used in individuals with elevated intracranial pressure, diabetes mellitus or hypothyroidism.

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Side effects Genotropin

In adults, negative symptoms associated with fluid retention may develop: among them are myalgia, peripheral edema, pastosity of the legs, paresthesia and arthralgia. These signs are often of weak or moderate intensity, develop during the first months of therapy and disappear on their own or after a reduction in the dosage of the drug. The frequency of these disorders is determined by the dosage of the drug and the age of the patient, and may also be inversely proportional to the age at which the person developed STH deficiency. In children, such disorders occur quite rarely.

Other side effects include:

• disorders affecting the functioning of the central nervous system: occasionally, there is an increase in the level of intracranial pressure, which is benign in nature. Edema in the area of the optic nerve may also occur;
• problems with endocrine function: diabetes mellitus type 2 may occasionally develop. In addition, a decrease in serum cortisol values is noted. The therapeutic significance of such a phenomenon is considered limited;
• lesions in the area of the musculoskeletal structure: dislocations or subluxations of the femoral head, which are accompanied by pain in the area of the knee with the hip and limping. Scoliosis may occur in people with Prader-Willi syndrome (because the drug increases the growth rate). Myositis is observed sporadically (it may develop under the influence of the preservative m-cresol, which is a component of the drug);
• allergy symptoms: itching and rashes on the epidermis;
• local manifestations: pain, rashes, a feeling of numbness, as well as itching, swelling and hyperemia with lipoatrophy appear at the injection site;
• other disorders: leukemia has been reported in isolated cases in children, but the incidence of leukemia is similar to that reported in children without growth hormone deficiency.

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Overdose

Manifestations of acute intoxication are the development of hypoglycemia first, and later hyperglycemia. With prolonged overdose, the known effects of excess human STH (such as gigantism or acromegaly) may occur.

To eliminate such manifestations, it is necessary to stop taking the medication and perform symptomatic procedures.

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Interactions with other drugs

The combination of the drug with GCS leads to a weakening of its stimulating effect on growth processes.

Combining Genotropin with the substance thyroxine can lead to the development of a moderate form of thyrotoxicosis.

When used simultaneously, the drug can increase the clearance rates of compounds that are metabolized by the CYP3A4 isoenzyme (including GCS, sex hormones, cyclosporine, and anticonvulsants). The clinical significance of this effect has not yet been studied.

Storage conditions

Genotropin should be kept in a dark place out of reach of children. Temperature values are within the range of 2-8°C. Neither the prepared solution nor the cartridge should be frozen.

Shelf life

Genotropin may be used within 3 years from the date of manufacture of the medicinal product. The shelf life of the finished product (when kept in a refrigerator at a temperature of 2-8°C) is 1 month.

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Analogues

Analogues of the drug are Biorostan, Zomacton, Somatin and Biosoma with Nutropin, as well as Groutropin, Rastan, Jintropin with Norditropin and Humatrop.

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