China approval for Xtandi as prostate cancer therapy

China’s Center for Drug Evaluation (CDE) of the China National Medical Products Administration (NMPA) has approved Japanese pharma major Astellas’ (TYO:4503) Xtandi (enzalutamide) for the treatment of patients with metastatic hormone-sensitive prostate cancer (mHSPC).

The approval is based on positive results from the Phase III global ARCHES and China ARCHES studies. China ARCHES used a surrogate endpoint (time to PSA progression) to bridge to the global ARCHES study results. In the China ARCHES study, 180 Chinese patients with mHSPC in mainland China were randomized to receive Xtandi plus ADT or placebo plus ADT.

Results show Xtandi plus ADT significantly reduced the risk of PSA progression by 87% vs placebo plus ADT (HR 0.130 [95%CI 0.076,0.222]; P<0.0001). Radiographic progression free survival (rPFS), time to castration resistance (TTCR), and PSA undetectable rate were among the secondary endpoints improved with Xtandi in combination with ADT compared to placebo plus ADT. These findings again show consistent positive results for XTANDI in line with those in Astellas’ global Phase III ARCHES study. In China ARCHES, the safety of Xtandi plus ADT was consistent with the known safety profile for the medication. Overall, these findings support the earlier usage of Xtandi in this treatment setting.