Letrazole Steroid Powders Femara Hormone for Anti-Breast Cancer
Other name: Femara
Appearance: White or light yellow crystal
Usage: Used as API in Treatment of breast disease
Letrozole (INN, trade name Femara) is an oral non-steroidal aromatase inhibitor that has been introduced for the adjuvant treatment of hormonally sensitive breast cancer
Estrogens are produced by the conversion of androgens through the activity of the enzyme aromatase. Letrozole blocks estrogen production in this way through a competitive and reversible binding to the heme of its cytochrome P450 unit. The action is specific and letrozole does not reduce the production of minerals or corticosteroids. On the contrary, the antiestrogenic action of tamoxifen, the main medical therapy prior to the arrival of aromatase inhibitors, is because it interferes with the estrogen receptor, rather than inhibiting estrogen production.
Letrozole has been used for ovarian stimulation by fertility doctors since 2001 because it has fewer side-effects than clomiphene (Clomid) and less chance of multiple gestation. A Canadian study presented at the American Society of Reproductive Medicine 2005 Conference suggested that letrozole may increase the risk of birth defects. A more detailed ovulation induction follow-up study found that letrozole, compared with a control group of clomiphene, had significantly lower congenital malformations and chromosomal abnormalities at an overall rate of 2.4% (1.2% major malformations) compared with clomiphene 4.8% (3.0% major malformations). Despite this, India banned the usage of letrozole in 2011, citing potential risks to infants.In 2012, an Indian parliamentary committee said that the drug controller office colluded with letrozole's makers to approve the drug for infertility in India and also stated that letrozole's use for infertility was illegal worldwide; however, such off-label uses are legal in many countries such as the US and UK.
The anti-estrogen action of letrozole has been shown to be useful in pretreatment for termination of pregnancy, in combination with misoprostol. It can be used in place of mifepristone, which is expensive and unavailable in many countries.
Letrozole is sometimes used as a treatment for gynecomastia, although it is probably most effective at this if caught in an early stage (such as in users of anabolic steroids).
Letrozole has also been shown to delay the fusing of the growth plates in mice.When used in combination with growth hormone, letrozole has been shown effective in one adolescent boy with a short stature.
White or off-white crystaline powder
Soluble in Chloroform;
(1)Maximum absorption in wavelength
(2)Infrared spectrum should be
|In accordance with the dominant peak|
Loss on drying