Toxicity & Pharmacokinetics of 2 & 3-weekly Docetaxel in Metastatic Hormone-Sensitive Prostate Cancer (mHSPC)

This pilot study is designed to investigate the toxicity and PK of 2-weekly and 3-weekly docetaxel in mHSPC. Furthermore, a mechanism-based population PK/ pharmacodynamics (PD) model will be developed to provide a better understanding of the complex relationships between the drug exposure and toxicity profiles of docetaxel in mHSPC. In addition, selected pro-inflammatory and macrophage-associated cytokines will be collected to assess the potential role of these cytokines as the early markers of docetaxel resistance in patients with mHSPC. (Cytokines: macrophage inhibitory cytokine 1 (MIC1), interleukin (IL)-1ra, IL-1β, IL-4, IL-6, IL-12, and IFNγ). Serological response, defined as a prostate-specific antigen (PSA) level of \<0.2 ng/mL at 12 months, and progression-free survival at 12 months are selected as the secondary clinical endpoints of the study.