Trial Evaluating the Safety of 2 Schedules of Cabazitaxel in Elderly Men With mCRPC Previously Treated With a Docetaxel

Inclusion Criteria:

1. Patient aged ≥ 65 years with mCRPC previously treated with docetaxel
2. Medical or surgical castration with castrate level of testosterone (\< 50 ng/dl) based on the EAU definition of castrate level of testosterone
3. Progressive disease according to PCWG2
4. Histologically proven prostate carcinoma
5. Health status allowing use of chemotherapy: G8 \> 14; or G8 score ≤ 14 with geriatric assessment concluding to reversible impairment allowing use of chemotherapy
6. ECOG-PS 0, 1 or 2(ECOG-PS 2 should be related to prostate cancer)
7. Adequate hematologic, liver and renal functions:

   1. Neutrophil count ≥1.5 109/L
   2. Haemoglobin ≥10 g/ dL
   3. Platelet count ≥100.109/L
   4. Total bilirubin ≤ 1 the upper limit of normal (ULN)
   5. Transaminases ≤ 1.5 ULN
   6. Serum creatinine ≤ 2.0 ULN
8. Ongoing LHRH therapy at study entry
9. Signed informed consent

Exclusion Criteria:

1. History of severe hypersensitivity reaction (≥grade 3) to docetaxel
2. History of severe hypersensitivity reaction (≥grade 3) to polysorbate 80 containing drugs
3. Uncontrolled severe illness or medical condition (including uncontrolled diabetes mellitus)
4. Concurrent or planned treatment with strong inhibitors or strong inducers of cytochrome P450 3A4/5 (a one week wash-out period is necessary for patients who are already on these treatments) (see Appendix E)
5. PS \>2 not related to prostate cancer disease
6. G8 ≤ 14 with geriatric assessment contra-indicating standard cabazitaxel regimen
7. Concomitant vaccination with yellow fever vaccine
8. Patient who cannot be regularly followed or cannot answer to quality of life questionnaires because of psychological, social, familial or geographic reasons
9. Participation in another clinical trial with any investigational drug within 30 days prior to study enrolment.