Xuanzhu Biopharm's Xuanyuening® Approved for Two Breast Cancer Indications

HONG KONG, May 15, 2025 — The National Medical Products Administration announced a significant development in the oncology field with the approval of Bireociclib tablets, marketed under the name Xuanyuening®. Developed by Xuanzhu Biopharmaceutical, this Class 1 anti-tumor drug offers new treatment options for HR+/HER2- breast cancer patients in China, promising improved outcomes for many battling this disease.

Bireociclib is designed for adults with advanced or metastatic breast cancer who exhibit positive hormone receptor status and negative human epidermal growth factor receptor 2 (HER2) markers. The drug is approved for use in conjunction with fulvestrant in patients whose disease progresses despite prior endocrine therapy. Remarkably, it is the sole CDK4/6 inhibitor approved in China for use as monotherapy in patients who have undergone two or more endocrine therapies and chemotherapy during the metastatic stage. With approximately 420,000 new breast cancer cases annually in China, Bireociclib offers a vital new option for the nearly 100,000 cases that are advanced-stage.

Breast cancer remains the most prevalent malignant tumor among women worldwide, with about 70% classified as hormone receptor-positive. While CDK4/6 inhibitors have extended survival rates, challenges still abound, including limited efficacy in premenopausal patients, poor prognosis for those with visceral crisis, adverse drug reactions, and primary drug resistance. Bireociclib, targeting CDK2, 4, 6, and 9, blocks tumor cell proliferation while minimizing hematological toxicity. This dual-action approach not only inhibits tumor growth effectively but also enhances patient tolerance, addressing several of the existing barriers in treatment.

Clinical trials for Bireociclib were tailored to the unique characteristics of Chinese breast cancer patients, who generally experience an earlier onset age and a higher rate of Luminal B-type tumors and primary drug resistance, resulting in poorer prognoses compared to Western populations. The trials included diverse patient demographics with substantial pre-treatment histories: 23.9% had received advanced chemotherapy, 25.6% were resistant to primary drugs, 37% were premenopausal, and 68.2% had visceral metastases. In combination therapy, median progression-free survival reached 14.7 months as assessed by researchers and 17.5 months according to the Blinded Independent Review Committee (BIRC). As a standalone treatment in later stages, Bireociclib achieved up to 11 months of progression-free survival, setting a global record for similar therapies.

The market potential for Bireociclib is vast, given the rising incidence of breast cancer and increasing demand for efficient therapies. Experts predict the CDK4/6 inhibitor market in China to expand to tens of billions of yuan over the next five years. Thanks to its unique indications and favorable efficacy, Bireociclib is poised to capture a significant share of this market.

Xuanzhu Biopharmaceutical, the innovative arm of Sihuan Pharmaceutical, is actively working to integrate Bireociclib into China's national medical insurance system. This effort aligns with their commitment to making cancer treatments accessible, affordable, and effective, contributing meaningfully to the "Healthy China" initiative. This strategy not only underscores Xuanzhu Bio's dedication to corporate social responsibility but is also anticipated to accelerate the adoption of Bireociclib in clinical settings, vastly improving the lives of breast cancer patients throughout the country.