Letrozole

Breast cancer is the malignant tumor with the highest incidence rate among women globally, of which approximately 70% are hormone receptor-positive subtypes, and endocrine therapy is the core solution for the long-term management of such patients. As a third-generation aromatase inhibitor, letrozole inhibits aromatase activity with high specificity, blocks the conversion of androgens to estrogens in postmenopausal women, and reduces circulating estrogen levels, thereby inhibiting the growth of hormone-dependent tumor cells. At present, in addition to being used for adjuvant treatment of postmenopausal patients with early breast cancer and first-line and second-line treatment of advanced breast cancer, this drug is also widely used to induce ovulation in the field of assisted reproduction, covering tens of millions of applicable people in the two major fields of oncology and reproduction.

In 2023, the global letrozole market size was approximately USD 1.28 billion, with a compound annual growth rate of 3.2% in the past five years. The Chinese market accounts for approximately 18% of the global market, with a growth rate of 4.7%, which is higher than the global average. As the core patent has long expired, the current global market is dominated by generic drugs. China is the core supplier of letrozole active pharmaceutical ingredients (APIs), with a production capacity accounting for more than 65% of the global total production capacity. The domestic preparation market has completed three batches of national centralized drug procurement, and the winning bid price has dropped by more than 90% compared with the original research drug, which has greatly improved clinical accessibility and further driven the demand growth of upstream APIs.

The original research enterprise of letrozole is Novartis, and the original research brand name is "Femara". The core compound patent expired in 2011 in the United States, the European Union and China. The main dosage form approved for the original research drug is tablet, with a specification of 2.5mg. It has been included in the *Catalogue of Chemical Reference Preparations* of China, and is also a reference preparation designated by the FDA. Up to now, there are more than 30 registrations of letrozole APIs filed with the Center for Drug Evaluation (CDE) of China, among which more than 20 registration numbers are in Status A. Nearly 40 domestic enterprises have obtained marketing approval for letrozole tablets, with sufficient supply. (Data as of October 2024, please refer to the official CDE website for the latest information)

CATO provides a full set of letrozole impurity reference standards, covering full-path impurities such as those generated in the synthesis process and degradation products. All products meet the compliance requirements of multiple regulations such as the Chinese Pharmacopoeia and FDA regulations. Most products are in stock. For in-stock orders placed before 16:00, delivery can be made on the same day, which can fully meet various needs in the stages of API R&D, quality research and registration declaration.