Factory Supply USP/ EP 99% Letrozole ;Femara ;Letrozol powder CAS NO.112809-51-5

Introduction:                              

1.CAS NO: 112809-51-5

2.letrozole Content: 99%

3.Molecular Formula: C17H11N5

4. Molecular Weight: 285.31

5. Appearance white or off-white powder

6. Melting point 181-183 ° C

7. Letrozole is an oral non-steroidal inhibitor for the treatment of hormonally-responsive breast cancer after surgery. letrozole prevents the aromatase from producing estrogens by competitive, reversible binding to the heme of its cytochrome p450 unit, the action is specific,and letrozol does not reduce production of mineralo-or corticosteroids.

Letrozole is a new generation aromatase inhibitor, is a synthetic derivative of benzyl triazole, letrozole by inhibiting aromatase, estrogen levels drop, thereby eliminating the stimulating effect of estrogen on tumor growth. Chemotherapy and radiotherapy for breast cancer.

Function:                                     

Letrozole is a new generation of highly selective aromatase inhibitors for synthetic benzyl triazole derivatives, by inhibiting aromatase, estrogen levels drop, thereby eliminating the stimulating effect of estrogen on tumor growth. In vivo activity than the first-generation aromatase inhibitor aminoglutethimide 150-250 times stronger. Due to its high selectivity, without affecting glucocorticoid mineralocorticoid and thyroid function, high doses of a corticosteroid like substances secreted without inhibition, and therefore it has a high therapeutic index. The pre-clinical studies have shown that letrozole for the whole body system and there is no potential target organ toxicity, no mutagenic and carcinogenic effects, and less side effects, well tolerated, and other aromatase inhibitors and anti- estrogen drugs compared to stronger anti-tumor effect. Suitable for patients with early breast cancer treatment as well as anti-estrogen therapy after treatment of advanced breast cancer in postmenopausal invalid.
December 2005 the British Medicines and Healthcare products regulatory approvals Novartis produced letrozole (Femara) is used to treat breast cancer patients, allowing it to be used after surgery, postmenopausal hormone-positive early invasive breast cancer patients. This is the second in June 2005 approved the British AstraZeneca Arimidex approved the first two aromatase inhibitors. Two drugs in clinical trials have shown that, compared with the current standard tamoxifen treatment can better prevent the risk of breast cancer recurrence.

Letrozole and anastrozole tablets distinguish letrozole tablets: for postmenopausal women with advanced breast cancer, second-line therapy for the treatment of multiple anti-estrogen therapy after failure.

Anastrozole: selective triazole aromatase inhibitors a potent, can inhibit the cytochrome P-450 aromatase enzyme depends thus blocking the biosynthesis of estrogens, and estrogen to stimulate breast cancer cells The main factor in the growth. The product of human placental aromatase 50% inhibitory concentration (IC50) is

15nmol / L.

Application:                                

1. Treatment of postmenopausal women with advanced breast cancer (estrogen receptor, progesterone receptor positive or unknown receptor status), used for anti-estrogen therapy after the failure of second-line treatment;

2. For locally advanced or spread after the first-line treatment of postmenopausal breast cancer (foreign data);

3. For the received standard adjuvant tamoxifen therapy in postmenopausal breast cancer after five years of adjuvant therapy in patients with extension (foreign data);

4. Postoperative adjuvant therapy for hormone-positive early breast cancer patients.

Specification: