Firmagon

Firmagon is a substance from the category of hormonal antagonists and a medication used in oncology.

When using the drug in compliance with all instructions, there is a rapid decrease in luteotropin and follitropin levels, which ultimately reduces testosterone levels. Intraplasmic dihydrotestosterone values also decrease.

This medication demonstrates efficacy in suppressing testosterone secretion below medical castration levels (0.5 mg/ml) and maintaining these levels. A standard monthly dose (administered once) causes sustained suppression of testosterone secretion for at least 12 months in 97% of treated men.

Indications Firmagona

It is used in men in cases of hormone-dependent prostate carcinoma, which is widespread.

Release form

The drug is released in the form of a lyophilisate for injection, inside vials with a capacity of 0.08 or 0.12 g. In addition, the box contains a syringe filled with solvent (injection liquid), with a volume of 3 or 4.2 ml, needles, adapters for vials and piston rods.

Pharmacodynamics

Carcinoma affecting the prostate is sensitive to androgens and therefore responds to therapy that eliminates the source of these hormones.

The drug acts as a selective antagonist of gonadorelin. It is reversibly and competitively synthesized with the endings of the pituitary gonadorelin, quickly reducing the volumes of released luteotropins, gonadotropins and follitropins, which induces the release of testosterone by the testicles.

Gonadorelin blockers differ from its antagonists in that they do not lead to the development of a luteotropin release followed by a testosterone release and stimulation of tumor growth. All this can potentially cause an exacerbation of the symptoms of the disease after the start of the treatment course.

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Pharmacokinetics

Suction.

With subcutaneous injection of 0.24 g degarelix with values of 40 mg/ml in patients with prostate carcinoma, the AUC level of 0-28 days is 635 (in the range of 602-668) ng/ml; Cmax values are 66 (in the range of 61-71) ng/ml and are recorded after 40 (in the range of 37-42) hours. Average values are 11-12 ng/ml with the introduction of the 1st portion, as well as 11-16 ng/ml when using maintenance doses (80 mg) with values of 20 mg/ml.

Plasma Cmax of degarelix decreases in 2 stages with a mean half-life of approximately 29 days for the maintenance dose. The prolonged half-life with subcutaneous injection is due to the extremely low rate of release of degarelix from depots formed at the injection sites.

The pharmacokinetics of the drug is determined by its concentration inside the injection fluid. Since the bioavailability and Cmax values decrease with increasing concentration, it is prohibited to use any other concentrations of the drug that are not prescribed.

Distribution processes.

The volume of distribution in elderly volunteers was approximately 1 L/kg. Intraplasmic protein synthesis was approximately 90%.

Exchange processes.

Degarelix is subject to standard peptide degradation during its passage through the hepatobiliary system; the major portion of the substance is secreted in the faeces in the form of peptide fragments.

When administered subcutaneously, no metabolic elements with medicinal activity are observed in the blood plasma. In vitro testing has shown that degarelix does not act as a substrate for the CYP450 hemoprotein structure in humans.

Excretion.

In men without renal problems, about 20-30% of degarelix (1st IV injection) is excreted through this system. It is assumed that the remaining 70-80% is excreted via the hepatobiliary system.

The clearance rate of the drug after administration of a single dose (0.864-49.4 mcg/kg) of the solution in elderly patients is 35-50 ml/hour/kg.

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Dosing and administration

The medication is started by administering the initial dosage to the patient. Then it is used once a month. At first, the medication is administered in 0.24 g doses – through 2 subcutaneous injections, each of 0.12 g.

During the maintenance course, the monthly dose is 0.08 g. The first maintenance injection should be administered 1 month after the initial injection.

Injections should be performed exclusively by the subcutaneous method, in the abdominal area. The injection areas should be changed periodically. The area for the procedure should be selected taking into account that it should not be compressed by clothing (you cannot inject the medicine in the area where you wear a belt, on the waist), and should not be located near the ribs.

The effect of Firmagon is verified by monitoring blood hormone levels.

Because this drug does not induce an increase in testosterone levels, it is not necessary to prescribe antiandrogen agents to protect against testosterone surge at the beginning of treatment.

It is prohibited to use the solution intravenously.

In severe stages of liver/kidney failure, the drug is used with extreme caution.

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Use Firmagona during pregnancy

Firmagon is not intended for use in women.

Contraindications

Contraindicated for use by individuals with severe intolerance to the components of the medication.

Caution is required when administering to people with severe renal dysfunction.

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Side effects Firmagona

The main side effects of the therapeutic agent are:

• febrile neutropenia or anemia;
• signs of allergy and intolerance in the form of anaphylaxis;
• hyperglycemia, weight loss or gain, increased cholesterol levels, decreased appetite, diabetes mellitus and changes in blood Ca levels;
• headaches, decreased libido, insomnia, dizziness and depression;
• dyspnea;
• deterioration of visual acuity;
• tachycardia or arrhythmia;
• increased blood pressure and hot flashes;
• diarrhea, xerostomia, vomiting, constipation and nausea;
• increased values of intrahepatic transaminases;
• urticaria, hyperhidrosis, alopecia, night sweats, erythema and itching;
• myalgia, swelling or discomfort affecting the joints;
• nocturia, polakiuria, urinary incontinence or urge to urinate, and renal failure;
• testicular atrophy, impotence and gynecomastia;
• manifestations in the injection area, severe fatigue, flu-like condition, fever or chills.

If you experience any uncharacteristic side effects while using the medication, you should consult your doctor regarding a possible change in your treatment regimen.

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Overdose

There have been no reported cases of poisoning with Firmagon yet.

In case of intoxication, it is necessary to monitor the condition of the victim, carrying out symptomatic or supportive measures if necessary.

Storage conditions

Firmagon should be stored at temperatures no higher than 25°C.

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Shelf life

Firmagon is approved for use for a period of 36 months from the date of manufacture of the therapeutic product.

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Application for children

The drug is not used in pediatrics.

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Analogues

The analogs of the drug are Zoladex, as well as Ichsbira and Zytiga.

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