A Phase III of Cabazitaxel and Pelvic Radiotherapy in Localized Prostate Cancer and High-risk Features of Relapse

Inclusion Criteria: 1. Any T histologically confirmed adenocarcinoma of the prostate 2. No clinically or radiologically suspected metastases, including no enlarged pelvic lymph nodes (\> 1 cm in small diameter) 3. Gleason score ≥ 6 4. Meets at least 2 of the following criteria for high-risk: * Gleason score ≥ 8 * T3 or T4 disease (T3 defined by MRI is acceptable) * Prostate-specific antigen equal or greater than 20 ng/mL 5. No prior treatment for prostate cancer except lymph node dissection (patients with pN- and pN+ disease can be accrued) or ADT (started up to 6 weeks before randomization). 6. 18 years ≤ Age ≤ 75 years 7. Eastern Cooperative Oncology Group (ECOG) 0-1 performance status 8. Expected life expectancy of more than 10 years 9. Absolute neutrophil count ≥ 1.5 x 10⁹/L 10. Platelets ≥ 100 x 10⁹/L 11. Hb ≥ 9.0 g/dL 12. Hepatic function: serum bilirubin ≤ 1 upper limit of normal (ULN); aspartate aminotransferase (AST) and alanine aminotransferase (ALT) ≤ 2.5 x ULN 13. Renal function (creatinine clearance using the Chronic Kidney Disease Epidemiology group (CKD-EPI) formula ≥ 60 mL/min). 14. Potentially reproductive patients must agree to use an effective contraceptive method while on treatment and for 6 months after the final dose of investigational product. 15. Patients must be affiliated to a Social Security System or should fulfill the country legislation for clinical trials. 16. Patients who have received the information sheet and signed the informed consent form. 17. Patients must be willing and able to comply with scheduled visits, treatment plan, laboratory tests and other study procedures Exclusion Criteria: 1. Patients with other known concurrent severe and/or uncontrolled medical disease which could compromise participation in the study, such as: 1. infection, 2. cardiac disease such as uncontrolled hypertension, congestive cardiac failure, ventricular arrhythmias, active ischemic heart disease, myocardial infarction within one year, left ventricular ejection fraction (LVEF) \> grade 2, 3. uncontrolled diabetes mellitus, 4. current active hepatic or biliary disease (with exception of subjects with Gilbert's syndrome, asymptomatic gallstones, stable chronic liver disease per investigator assessment), 5. renal disease, 6. active GI tract ulceration, malabsorption syndrome, disease significantly affecting gastrointestinal function, or resection of the stomach or small bowel. Subjects with active, uncontrolled ulcerative colitis are also excluded, 7. known severely impaired lung function (spirometry and diffusing capacity of the lungs for carbon monoxide (DLCO) 70% or less of normal and O2 saturation of 88% or less at rest on room air). 2. Other prior malignancy within the last 5 years, except basal cell skin cancer 3. Physical or psychological condition that would preclude study compliance 4. Hypersensitivity to cabazitaxel (hypersensitivity reaction ≥grade 3), to other taxanes, or to any excipients of the formulation including polysorbate 80 5. Patients with significantly altered mental status prohibiting the understanding of the study or with psychological, familial, sociological or geographical condition potentially hampering compliance with the study protocol and follow-up schedule; those conditions should be discussed with the patient before registration in the trial. 6. Patients who received any other investigational drugs within the 30 days prior to the start of cabazitaxel. 7. Previous pelvic irradiation that make prostatic irradiation impossible 8. Severe GI disorders precluding pelvic irradiation 9. Patients already included in another therapeutic trial involving an experimental drug 10. Individual deprived of liberty or placed under the authority of a tutor. 11. Concomitant prohibited treatment. Concurrent or planned treatment with strong inhibitors or strong inducers of cytochrome P450 3A4/5 (see Appendix 6). A one week wash-out period is necessary for patients who are already on these treatments