Estrolet
Estrolet: instructions for use and reviews
- 1. Release form and composition
- 2. Pharmacological properties
- 3. Indications for use
- 4. Contraindications
- 5. Method of application and dosage
- 6. Side effects
- 7. Overdose
- 8. Special instructions
- 9. Application during pregnancy and lactation
- 10. Use in childhood
- 11. In case of impaired renal function
- 12. For violations of liver function
- 13. Use in the elderly
- 14. Drug interactions
- 15. Analogs
- 16. Terms and conditions of storage
- 17. Terms of dispensing from pharmacies
- 18. Reviews
- 19. Price in pharmacies
Latin name: Estrolet
ATX code: L02BG04
Active ingredient: letrozole (Letrozole)
Manufacturer: LLC "Nativa" (Russia); Pharmstandard-UfaVITA (Russia)
Description and photo update: 2019-08-07
Prices in pharmacies: from 901 rubles.
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Estrolet is an antineoplastic drug, an inhibitor of estrogen synthesis.
Release form and composition
The drug is available in the form of film-coated tablets: yellow, round, biconvex, white core (10 pcs. In blisters, in a cardboard box 1, 3, 6, 9 or 10 packs, 10, 30, 60, 90 or 100 pcs. In polymer bottles, in a cardboard box 1 bottle; each pack also contains instructions for the use of Estrolet).
1 tablet contains:
- active substance: letrozole - 2.5 mg;
- auxiliary components: magnesium aluminometasilicate, sodium croscarmellose, colloidal silicon dioxide, magnesium stearate, ludipress (lactose monohydrate, povidone, crospovidone);
- composition of the film shell: Opadray II yellow 85F32733 (polyvinyl alcohol, macrogol 3350, titanium dioxide, yellow iron oxide, talc).
Pharmacological properties
Pharmacodynamics
Estrolet is an anticancer drug that inhibits the synthesis of estrogens, the mechanism of action of which is due to the property of its active substance, letrozole.
Letrozole selectively inhibits the enzyme of estrogen synthesis, aromatase, by highly specific competitive binding to heme of cytochrome P 450, which is a subunit of aromatase. As a result of the antiestrogenic action of letrozole, the blocking of estrogen synthesis is observed in both peripheral and tumor tissues.
The formation of estrogens in the postmenopausal period occurs mainly with the participation of the aromatase enzyme, which converts androstenedione, testosterone and other androgens synthesized in the adrenal glands into estrone and estradiol. Regular intake of letrozole at a dose of up to 5 mg causes a decrease in the plasma concentration of estradiol, estrone and estrone sulfate by 75–95% of the initial level. The suppression of estrogen synthesis persists during the entire period of treatment.
The use of Estrolet in the range of therapeutic doses does not disrupt the synthesis of steroid hormones in the adrenal glands. There were no violations of the synthesis of aldosterone or cortisol during the test with adrenocorticotropic hormone (ACTH). There is no need for additional prescription of mineralocorticoids and glucocorticoids.
The blockade of estrogen biosynthesis does not cause the accumulation of androgens, which are estrogen precursors. In addition, there were no changes in the function of the thyroid gland and the lipid profile, violations of the levels of luteinizing and follicle-stimulating hormones in the blood plasma, an increase in the frequency of strokes and myocardial infarctions.
Estrolet has little effect on increasing the incidence of osteoporosis, but the incidence of bone fractures is comparable to that in healthy people of the same age.
The use of letrozole as an adjuvant therapy for early stages of breast cancer reduces the risk of recurrence, reduces the likelihood of developing secondary tumors, and increases disease-free survival for 5 years. With prolonged adjuvant therapy with letrozole, the risk of recurrence is reduced by 42%.
Pharmacokinetics
After oral administration, letrozole is rapidly absorbed from the gastrointestinal tract. Its average bioavailability is 99.9%. With the simultaneous intake of food, the absorption rate is slightly reduced. The maximum concentration (C max) of letrozole in the blood when taking tablets on an empty stomach is reached after 1 hour and averages 129 nmol / l, when taken with food - after 2 hours (average 98.7 nmol / l). It should be noted that the degree of absorption of letrozole does not change.
Estrolet can be taken regardless of food intake, since a slight change in the rate of absorption has no clinical significance.
Plasma protein binding (mainly albumin) is approximately 60%. The level of letrozole in erythrocytes reaches 80% of the concentration in blood plasma. The apparent volume of distribution of letrozole at equilibrium is approximately 1.87 L / kg. Equilibrium concentration is reached within 14–42 days with a daily intake of 2.5 mg.
The pharmacokinetics of the active substance Estrolet is nonlinear, with prolonged use, no cumulation is noted.
Letrozole is metabolized mainly by the action of isoenzymes CYP3A4 and CYP2A6 of cytochrome P 450 with the formation of an inactive carbinol compound.
Excretion in the form of metabolites occurs mainly through the kidneys and to a small extent through the intestines. The final half-life (T 1/2) is 48 hours.
The pharmacokinetic parameters of letrozole in patients of different age groups or in renal failure do not change.
With an average degree of liver failure (severity B on the Child-Pugh scale), the mean total concentration (AUC) values increase slightly, remaining within the acceptable range. In severe liver dysfunction (severity C on the Child-Pugh scale), there is an increase in AUC by 95%, and T 1/2 by 187%. But, due to the good tolerance of high doses of Estrolet (up to 10 mg per day), there is no need to change the therapeutic dose of letrozole in these cases.
Indications for use
- early stage of invasive breast cancer (provided that the cells have hormone receptors) in postmenopausal women - as adjuvant therapy;
- early-stage invasive breast cancer in postmenopausal women after completion of 5-year standard adjuvant tamoxifen therapy;
- common hormone-dependent forms of breast cancer in postmenopausal women - as first-line therapy;
- common hormone-dependent forms of breast cancer with the progression of the disease or the development of a relapse after previous anti-estrogen therapy in postmenopausal women, including those caused artificially.
Contraindications
Absolute:
- endocrine status characteristic of the reproductive period;
- period of pregnancy;
- breast-feeding;
- age up to 18 years;
- hypersensitivity to the components of the drug.
With caution, Estrolet tablets should be used for renal failure with creatinine clearance (CC) less than 10 ml / min, severe liver failure (severity C on the Child-Pugh scale), lactase deficiency, lactose intolerance, glucose-galactose malabsorption syndrome, concomitant drug therapy agents with a low therapeutic index.
Estrolet, instructions for use: method and dosage
Estrolet tablets are taken orally, regardless of the meal.
Recommended dosage: 1 pc. (With 2.5 mg) once a day for an extended period. The duration of the course when the drug is prescribed as an extended adjuvant therapy is up to 5 years.
The use of Estrolet should be discontinued when signs of disease progression appear.
For the treatment of patients in old age, with hepatic failure or renal failure with CC more than 10 ml / min, dose adjustment is not required. But the appointment of Estrolet to patients with severe hepatic insufficiency (severity C on the Child-Pugh scale) requires constant monitoring of the woman's condition.
Side effects
- from the musculoskeletal system: very often - arthralgia; often - bone fractures, osteoporosis, myalgia, bone pain; infrequently - arthritis; frequency not established - snapping finger syndrome;
- from the digestive system: often - dyspepsia, nausea, vomiting, diarrhea, constipation; infrequently - dry mouth, stomatitis, abdominal pain, increased activity of liver enzymes: alanine aminotransferase (ALT) and aspartate aminotransferase (ACT); very rarely - hepatitis;
- dermatological reactions: often - increased sweating, alopecia, psoriasis-like rash, erythematous, maculopapular and / or vesicular skin rash; infrequently - urticaria, pruritus, dry skin; very rarely - angioedema, toxic epidermal necrolysis (Lyell's syndrome), Stevens-Johnson syndrome, anaphylactic reactions;
- from the nervous system: often - dizziness, headache, depression; infrequently - impaired taste, drowsiness, irritability, memory impairment, anxiety, nervousness, insomnia, dysesthesia, hypesthesia, paresthesia, carpal tunnel syndrome, episodes of cerebrovascular accident;
- from the lymphatic system and blood: infrequently - leukopenia;
- from the cardiovascular system: infrequently - increased blood pressure (BP), tachycardia, palpitations, ischemic heart disease (heart failure, angina pectoris, myocardial infarction), thromboembolism, thrombophlebitis of both superficial and deep veins; rarely - arterial thrombosis, pulmonary embolism, stroke;
- from the respiratory system, chest and mediastinal organs: infrequently - cough, shortness of breath;
- from the urinary system: infrequently - urinary tract infections, increased urination;
- from the genitals and mammary gland: infrequently - vaginal dryness, vaginal discharge, vaginal bleeding, pain in the mammary glands;
- on the part of the organ of vision: infrequently - eye irritation, cataracts, blurred vision;
- others: very often - flushing of the face and / or body, hot flashes; often - asthenia, increased fatigue, anorexia, peripheral edema, malaise, increased appetite, weight gain, hypercholesterolemia; infrequently - thirst, dryness of mucous membranes, decrease in body weight, hyperthermia (pyrexia), pain in tumor foci, generalized edema.
Overdose
Symptoms of an Estrolet overdose have not been established.
Treatment: there are no specific methods of treatment for overdose. The appointment of symptomatic and supportive therapy is recommended. Shown is the use of hemodialysis to remove letrozole from plasma.
special instructions
Side effects of Estrolet are usually associated with suppression of estrogen synthesis and are mild to moderate in severity.
Treatment with letrozole should be accompanied by monitoring of bone density, and in severe hepatic insufficiency (severity C on the Child-Pugh scale) - regular determination of blood cholesterol concentration.
Conception should not be allowed during the period of using Estrolet, therefore, women in the perimenopausal and early postmenopausal period should use reliable methods of contraception until a stable postmenopausal hormonal level is established.
Influence on the ability to drive vehicles and complex mechanisms
Due to the existing risk of dizziness and general weakness, during the period of treatment, care should be taken and, when undesirable phenomena appear, refrain from performing potentially hazardous activities that require a high concentration of attention and quick reactions, including driving vehicles and mechanisms.
Application during pregnancy and lactation
The use of Estrolet is contraindicated during the period of gestation and breastfeeding.
Pediatric use
The use of Estrolet is contraindicated in patients under 18 years of age.
With impaired renal function
Care should be taken when prescribing Estrolet for the treatment of patients with renal insufficiency (CC less than 10 ml / min).
For violations of liver function
Care should be taken when prescribing Estrolet for the treatment of patients with severe hepatic impairment (severity C on the Child-Pugh scale).
Use in the elderly
For elderly patients, dose adjustment is not required.
Drug interactions
There is no clinical experience of the simultaneous use of Estrolet with other antineoplastic agents.
The combination of Estrolet with cimetidine or warfarin does not cause clinically significant interactions.
According to the research results, letrozole has an inhibitory activity against the isoenzyme CYP2A6 of cytochrome P 450, which does not play a significant role in the metabolism of drugs.
It has been experimentally established that letrozole in a dose causing a hundred-fold excess of the equilibrium plasma concentration values, when combined with diazepam (a substrate for CYP2C19), does not significantly suppress its metabolism. Therefore, it is considered unlikely a clinically significant interaction of Estrolet with the isoenzyme CYP2C19.
It is recommended to use drugs with caution, the metabolism of which is mainly associated with the participation of isoenzymes CYP2A6 and CYP2C19, and with a narrow therapeutic index, in combination with letrozole.
Analogs
The analogues of Estrolet are: Letrozole, Letroza, Letrozole-Teva, Letrosan, Letrotera, Loreta, Nexazol, Oreta, Femara, Extraza, etc.
Terms and conditions of storage
Keep out of the reach of children.
Store at temperatures up to 25 ° C in a dark place.
Shelf life is 2 years.
Terms of dispensing from pharmacies
Dispensed by prescription.
Reviews about Estrolet
The anticancer drug Estrolet was developed and is being produced as part of the federal target program (Federal Target Program) "Strategy for the Development of the Pharmaceutical Industry of the Russian Federation for the Period until 2020", focused on import substitution of popular drugs. Since the generic began to be released not so long ago and the experience of its use is still small, there are currently practically no reviews from patients and doctors about Estrolet.
Presumably, since it is made in Russia, the drug will be prescribed primarily on preferential and free vacation.
Price for Estrolet in pharmacies
The price of Estrolet for a package containing 30 tablets can range from 1065 rubles.
Estrolet: prices in online pharmacies
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Drug name Price Pharmacy |
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Estrolet 2.5 mg film-coated tablets 30 pcs. 901 RUB Buy |
Maria Kulkes Medical journalist About the author
Education: First Moscow State Medical University named after I. M. Sechenov, specialty "General Medicine".
Information about the drug is generalized, provided for informational purposes only and does not replace the official instructions. Self-medication is hazardous to health!
