Femara (letrozole) coated tablets 2.5 mg. №30

Description

Femara Storage:

active substance: letrozole;

1 tablet contains 2.5 mg of letrozole;

excipients: colloidal anhydrous silica; microcrystalline cellulose; lactose monohydrate; magnesium stearate; corn starch; sodium starch glycolate
(type A); hydroxypropylmethylcellulose; polyethylene glycol 8000; talc; titanium
dioxide (E 171); iron oxide yellow (E 172).

Femara Dosage form.

Film-coated tablets.

Main physical and chemical properties: dark yellow, round, slightly biconvex tablets, film-coated with beveled edges; on the one hand – marking “FV”, on the other – “CG”.

Femara Pharmacotherapeutic group.

Means used for hormone therapy. Hormone antagonists and similar drugs. Aromatase inhibitors. Letrozole.

ATX code L02B G04.

Pharmacological properties.

Pharmacodynamics.

Letrozole – a non-steroidal aromatase inhibitor (inhibitor of estrogen biosynthesis); antitumor drug.

In cases where the growth of tumor tissue depends on the presence of estrogen, the elimination of the stimulant effect mediated by them is a prerequisite for inhibition of tumor growth.
In postmenopausal women, estrogens are produced primarily by the enzyme aromatase, which converts androgens synthesized in the adrenal glands (primarily androstenedione and testosterone) to estrone (E1) and estradiol (E2). Therefore, with the help of specific inhibition of the enzyme aromatase, it is possible to achieve inhibition of estrogen biosynthesis in peripheral tissues and in tumor tissue.

Letrozole inhibits aromatase by competitive binding to a subunit of this enzyme, cytochrome P450 heme, which reduces estrogen biosynthesis in all tissues.

In healthy postmenopausal women, a single dose of letrozole of 0.1 mg, 0.5 mg and 2.5 mg reduces serum estrone and estradiol levels (compared to baseline) by 75-78% and 78%, respectively. . The maximum reduction is achieved through
48-78 hours.

In postmenopausal women with advanced breast cancer, daily administration of letrozole 0.1 mg to 5 mg reduces plasma levels of estradiol, estrone and estrone sulphate by 75-95% of baseline. When using the drug at a dose of 0.5 mg or more in many cases, the concentrations of estrone and estrone sulfate are below the sensitivity limit of the method used to determine hormones. This indicates that with these doses of the drug is a more pronounced inhibition of estrogen synthesis. Estrogen suppression was maintained during treatment in all patients.

Indication.

· Adjuvant therapy for hormone-positive invasive breast cancer in the early stages in postmenopausal women.

· Extended adjuvant therapy for invasive early-stage breast cancer in postmenopausal women who have received standard adjuvant tamoxifen therapy for 5 years.

· First-line therapy for hormone-dependent advanced breast cancer in postmenopausal women.

· Treatment of common forms of breast cancer in postmenopausal women (natural or artificially induced) after recurrence or progression of the disease who have received prior antiestrogen therapy.

· Neoadjuvant therapy in postmenopausal women with hormone-positive, HER-2-negative breast cancer who do not respond to chemotherapy and do not require immediate surgery.

The effectiveness of the drug for patients with hormone-negative breast cancer has not been proven.

Contraindication.

· Hypersensitivity to the active substance or to any other component of the drug.

· Endocrine status characteristic of the premenopausal period.

· Pregnancy, breastfeeding.

· Women of reproductive age.