Femara
Femara: 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. Drug interactions
- 14. Analogs
- 15. Terms and conditions of storage
- 16. Terms of dispensing from pharmacies
- 17. Reviews
- 18. Price in pharmacies
Latin name: Femara
ATX code: L02BG04
Active ingredient: letrozole (Letrozole)
Producer: Novartis Pharma Stein (Switzerland)
Description and photo updated: 2018-26-11
Prices in pharmacies: from 6753 rubles.
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Femara is an anticancer drug used to treat breast cancer in postmenopausal women.
Release form and composition
The dosage form of Femara is film-coated tablets: dark yellow, somewhat biconvex, round, with beveled edges, “CG” is printed on one side, “FV” on the other (in a carton box there are 3 blisters of 10 tablets).
Composition of 1 tablet:
- active substance: letrozole - 2.5 mg;
- auxiliary components: corn starch - 9.5 mg; colloidal silicon dioxide - 0.5 mg; sodium carboxymethyl starch - 5 mg; lactose monohydrate - 61.5 mg; magnesium stearate - 1 mg; microcrystalline cellulose - 20 mg;
- shell: titanium dioxide - 0.249 mg; hypromellose - 1.838 mg; macrogol 8000 - 0.333 mg; talc - 1.331 mg; dye iron oxide yellow (17 268) - 0.249 mg.
Pharmacological properties
Pharmacodynamics
Femara is one of the anticancer drugs.
It has an antiestrogenic effect, selectively inhibits the enzyme of estrogen synthesis - aromatase, which occurs due to highly specific competitive binding with cytochrome P450 heme (a subunit of this enzyme). In peripheral and tumor tissues, it blocks the synthesis of estrogen.
Estrogens in postmenopausal women are formed mainly with the participation of the aromatase enzyme, which converts androgens synthesized in the adrenal glands into estradiol and estrone.
With daily use of 0.1–5 mg letrozole, there is a decrease in the plasma concentration of estradiol, estrone sulfate and estrone in the blood by 75–95% of the initial value. Suppression of estrogen synthesis is maintained throughout the treatment.
The use of Femara in therapeutic doses (0.1–5 mg) does not lead to a violation of the synthesis of steroid hormones in the adrenal glands, as a result of the test with ACTH (adrenocorticotropic hormone), violations of the synthesis of cortisol or aldosterone are not detected. The additional appointment of mineralocorticoids and glucocorticoids is not necessary.
The blockade of estrogen biosynthesis does not lead to the accumulation of androgens, which are precursors of estrogens. Also, during the period of therapy, changes in plasma concentrations of follicle-stimulating and luteinizing hormones in the blood, lipid profile and thyroid function, and an increase in the number of strokes and myocardial infarctions are not observed.
During the period of taking Femara, the frequency of osteoporosis increases slightly, while the frequency of bone fractures does not change.
With adjuvant therapy of early stages of breast cancer, the risk of progression is reduced, the survival rate without signs of disease increases for 5 years, and the likelihood of a tumor in another breast decreases.
Prolonged adjuvant therapy reduces the risk of disease progression by 42%. Femara's group showed a significant benefit in disease-free survival, whether or not lymph nodes were involved. With the involvement of lymph nodes, Femara's reception can reduce mortality by 40%.
Pharmacokinetics
Letrozole is absorbed quickly and completely in the gastrointestinal tract. The average bioavailability is 99.9%. Food intake decreases the absorption rate slightly.
Cmax (maximum concentration of the substance) is achieved on average in 1 or 2 hours and reaches 129 ± 20.3 or 98.7 ± 18.6 nmol / L (when taking the drug on an empty stomach or with food, respectively). At the same time, there is no change in the degree of absorption of letrozole as measured by AUC (area under the concentration-time curve). Letrozole can be taken with or without food, as slight changes in absorption rate are judged to be of no clinical significance.
The binding of letrozole to blood plasma proteins is about 60% (mainly with albumin - 55%). In erythrocytes, the concentration of the substance is approximately 80% of its plasma level. During the equilibrium period, the apparent Vd (volume of distribution) is approximately 1.87 ± 0.47 L / kg. The time to reach Css (equilibrium concentration) is 2–6 weeks with daily Femara intake in a daily dose of 2.5 mg. Pharmacokinetics is non-linear. With prolonged use, no cumulation was observed.
Letrozole is metabolized to a large extent by the isoenzymes CYP3A4 and CYP2A6. This results in the formation of a pharmacologically inactive carbinol compound.
It is excreted mainly by the kidneys in the form of metabolites, to a lesser extent through the intestines. Final T1 / 2 - 48 hours.
In patients with moderately severe hepatic impairment (on the Child - Pugh scale - class B), the average AUC values are higher, but they are within the range of values that are observed in the absence of liver dysfunction. With cirrhosis of the liver and severe impairment of its function (on the Child - Pugh scale - class C), the AUC and T1 / 2 indices increase (by 95 and 187%, respectively). Given the good tolerance of high daily doses of Femara (from 5 to 10 mg), there is no need to change the dosage regimen.
Indications for use
- early-stage breast cancer in the presence of hormone receptors in cells (prescribed for postmenopausal women as adjuvant therapy);
- breast cancer in the early stages after the end of standard adjuvant therapy with tamoxifen (prescribed for postmenopausal women as prolonged adjuvant therapy);
- common hormone-dependent forms of breast cancer (prescribed for postmenopausal women as first-line therapy);
- common forms of breast cancer in women who have received prior antiestrogen therapy (prescribed to women in natural or artificially induced postmenopausal women).
Contraindications
Absolute:
- endocrine status, which is characteristic of the reproductive period;
- age up to 18 years;
- pregnancy and lactation;
- individual intolerance to the components of the drug.
Before prescribing Femara to women with creatinine clearance less than 10 ml / min, the doctor should assess the ratio of benefit to risk, since there is no experience of using the drug in this group of patients.
Instructions for use of Femara: method and dosage
Femara is taken orally, daily, regardless of food intake.
The recommended daily dose is 2.5 mg at a time. The drug is intended for long-term therapy.
When using Femara as an extended adjuvant therapy, its duration is 5 years (no longer).
In cases where there are signs of disease progression, the drug is canceled.
In severe hepatic impairments, the patient's condition should be monitored continuously.
Side effects
Adverse reactions are usually mild or moderate. Their development is associated mainly with the suppression of estrogen synthesis.
Possible adverse reactions (> 10% - very common;> 1% and 0.1% and 0.01% and <0.1% - rarely; <0.01% - very rare):
- reproductive system: infrequently - pain in the mammary glands, vaginal discharge, vaginal bleeding, vaginal dryness;
- urinary system: infrequently - urinary tract infections, frequent urination;
- digestive system: often - diarrhea, constipation, dyspepsia, nausea, vomiting; infrequently - stomatitis, abdominal pain, xerostomia, increased activity of liver enzymes;
- hematopoietic system: infrequently - leukopenia;
- nervous system: often - depression, dizziness, headache; infrequently - impaired cerebral circulation (episodes), insomnia, drowsiness, memory impairment, anxiety, nervousness, irritability, dysesthesia, paresthesia, disturbances in taste, hypesthesia;
- respiratory system: infrequently - cough, shortness of breath;
- cardiovascular system: infrequently - tachycardia, palpitations, thrombophlebitis of superficial and deep veins, thromboembolism, increased blood pressure, ischemic heart disease (myocardial infarction, angina pectoris, heart failure); rarely - arterial thrombosis, pulmonary embolism, stroke;
- dermatological reactions: often - increased sweating, alopecia, skin rash (including psoriasis-like rash, erythematous, maculopapular, vesicular rash); infrequently - dry skin, pruritus, urticaria; very rarely - anaphylactic reactions, angioedema;
- musculoskeletal system: very often - arthralgia; often - bone pain, myalgia, bone fractures, osteoporosis; infrequently - arthritis;
- sense organs: infrequently - blurred vision, eye irritation, cataracts, impaired taste;
- others: very often - hot flashes (hot flashes); often - increased appetite, peripheral edema, increased fatigue, malaise, asthenia, weight gain, hypercholesterolemia, anorexia; infrequently - pain in tumor foci, weight loss, thirst, hyperthermia, generalized edema, dryness of mucous membranes.
Overdose
There are data on individual cases of overdose.
Any specific methods of therapy for Femara's overdose are unknown. Symptomatic / supportive therapy is indicated. Letrozole is excreted from plasma during hemodialysis.
special instructions
In severe violations of hepatic function, the patient's condition should be monitored continuously.
Influence on the ability to drive vehicles and complex mechanisms
During the period of therapy, when driving vehicles, care must be taken, which is associated with the possibility of dizziness and general weakness.
Application during pregnancy and lactation
According to the instructions, Femara is not prescribed during pregnancy / lactation.
Women in the perimenopausal and early postmenopausal period are advised to use reliable methods of contraception until a stable postmenopausal hormonal level is established.
Pediatric use
Femara therapy is contraindicated in patients under 18 years of age.
With impaired renal function
Before prescribing Femara to women with creatinine clearance less than 10 ml / min, it is first necessary to assess the ratio of benefit to possible risk (no experience of use).
For violations of liver function
In case of liver dysfunction in severe course (on the Child-Pugh scale - class C), the patient's condition should be monitored continuously.
Drug interactions
There is no clinical experience of using Femara in combination with other anticancer drugs.
With the combined use of Femara with drugs that are metabolized mainly with the participation of cytochrome P450 isoenzymes - 2A6 and 2C19 and have a narrow therapeutic index, caution should be exercised.
Analogs
Femara's analogues are Extraza, Nexazol, Loreta, Letroza, Oreta, Lestrodex, Letrotera, Letrozole, Estrolet, Letrosan.
Terms and conditions of storage
Store in a place protected from moisture at temperatures up to 30 ° C. Keep out of the reach of children.
The shelf life is 5 years.
Terms of dispensing from pharmacies
Dispensed by prescription.
Reviews about Femara
Reviews about Femara are mostly positive. It is noted that the drug is better tolerated than Tamoxifen. Side effects are rare. It is indicated that in order to prevent osteoporosis, biophosphanates are sometimes additionally prescribed to therapy.
Femara price in pharmacies
The approximate price for Femara (30 tablets) is 6773-7469 rubles.
Femara: prices in online pharmacies
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Drug name Price Pharmacy |
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Femara 2.5 mg film-coated tablets 30 pcs. RUB 6753 Buy |
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Femara tab. p.p. 2.5mg n30 RUB 7498 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!
