The board of directors of Sihuan Pharmaceutical Holdings Group Ltd. announced that the Phase II clinical trial application of Birociclib (XZP-3287, CDK4/6 inhibitor), a class 1 innovative drug under development by the Group's non-wholly owned subsidiary Xuanzhu Biopharmaceutical Co. Ltd. ("Xuanzhu Biopharmaceutical"), used as monotherapy or in combination with Abitherone acetate and prednisone in the treatment of metastatic prostate cancer has been approved by the Center for Drug Evaluation of the National Medical Products Administration (the " NMPA") of the People's Republic of China. Prostate cancer is one of the common malignant tumors in the genitourinary system of elderly men.

Its incidence rate and mortality rate rank second and fifth in the global spectrum of male malignant tumors, and sixth and seventh in Chinese men respectively. According to global market research and consulting firm Nova One Advisor, the global prostate cancer treatment market size is estimated to be $15.2 billion in 2021 and is expected to increase to $24.9 billion by 2030.