Toremifene

In the long-term endocrine therapy for estrogen receptor-positive breast cancer, toremifene is an important choice that balances efficacy and safety. As a non-steroidal triphenylethylene derivative, its mechanism of action is to competitively bind to estrogen receptors on the surface of tumor cells to block estrogen-mediated tumor proliferation signals. Meanwhile, it has partial estrogen-like activity, which can reduce the risk of adverse reactions such as endometrial hyperplasia and thromboembolism. Clinically, it is mainly used for the treatment of metastatic breast cancer in postmenopausal women with positive or unknown estrogen receptors, and can also be used for adjuvant endocrine therapy after surgery for early-stage breast cancer, especially suitable for the patient group that cannot tolerate the adverse reactions of tamoxifen.

The global toremifene market size maintains a steady growth trend. In 2023, the market size was approximately USD 180 million, with a compound annual growth rate maintained at around 3.2%. In terms of the domestic market, the terminal sales in public medical institutions exceeded RMB 700 million in 2023. As the drug has been included in the National Medical Insurance Catalogue and clinical guidelines list it as a first-line optional regimen for endocrine therapy, the market demand continues to be released. The competitive landscape presents a coexistence of original research drugs and generics. Three domestic generic drug companies have obtained preparation approvals. At present, the supply of API is jointly covered by imported original research products and a small number of domestic manufacturers. The price drop after the expansion of centralized procurement has further promoted the increase of clinical penetration rate.

The original research enterprise of toremifene is Orion Corporation of Finland, and the original trade name is Fareston. The core compound patent expired in 2007 in major markets such as Europe and the United States, and the Chinese compound patent also expired in 2007. The main dosage form approved for the original research product is tablet, with a specification of 60 mg, which has been included in the *Catalogue of Reference Preparations of Chemical Drugs* of China, and also included in the FDA Reference Preparations Catalogue. In terms of domestic API registration, there are currently 6 API registration numbers including those of the original research enterprise, among which 5 are in status A (approved for use in marketed preparations). Three domestic enterprises have obtained marketing approval for toremifene tablets. (Data as of June 2025, please refer to the official website of CDE for the latest information)

In response to the needs of toremifene quality research and compliance declaration, CATO provides a full set of impurity reference standards for this API. Most products are in stock. For in-stock products, orders placed before 16:00 will be shipped on the same day. All products meet the compliance requirements of multiple regulatory systems such as the Chinese Pharmacopoeia and FDA, and can fully support the full-process needs of preparation enterprises in methodology validation, stability study and registration declaration.