Study of Cabozantinib in Combination With Abiraterone in Chemotherapy-Naïve Subjects With Bone-Metastatic Castration-Resistant Prostate Cancer

Recruitment & Eligibility

Inclusion Criteria

Histologically or cytologically confirmed adenocarcinoma of the prostate.
Must be surgically or medically castrated (serum testosterone levels less than or equal to 50 ng/dL)
Must have castration-resistant prostate cancer (CRPC) with disease progression during LHRH therapy or after a surgical bilateral orchiectomy.
Bone metastasis related to prostate cancer
Adequate organ and marrow function
Capable of understanding and complying with the protocol requirements and signed the informed consent document
Sexually active subjects and their partners must agree to use medically accepted methods of barrier contraception (eg, male condom or female condom) as well as one other medically accepted method of contraception during the course of the study treatment and for 4 months after the last dose of study treatment.

Exclusion Criteria

Any prior treatment with abiraterone, enzalutamide, or any investigational agents blocking androgen receptor (AR) or androgen synthesis.
Any prior treatment with cabozantinib or participation in a prior clinical trial of cabozantinib.
Any prior cytotoxic therapy (including estramustine) or biologic therapy for the treatment of prostate cancer (a few exceptions will be allowed)
Any prior radionuclide therapy (eg, samarium 153, strontium 89, alpharadin)
Use of investigational agent within 28 days
Any pathological finding consistent with small cell carcinoma of the prostate
Known brain metastases or cranial epidural disease
Diagnosis of another malignancy within 2 years, except for superficial non-melanoma skin cancers, or localized, low grade tumors deemed cured and not treated with systemic therapy

Study & Design

Arm && Interventions

Group	Intervention	Description
Cabozantinib arm 1	cabozantinib	Subjects randomized to this arm will receive cabozantinb 40 mg daily with abiratarone and prednisone
Cabozantinib arm 1	abiraterone	Subjects randomized to this arm will receive cabozantinb 40 mg daily with abiratarone and prednisone
Cabozantinib arm 1	prednisone	Subjects randomized to this arm will receive cabozantinb 40 mg daily with abiratarone and prednisone
Cabozantinib arm 2	cabozantinib	Subjects randomized to this arm will receive cabozantinib 20 mg daily with abiraterone and prednisone
Cabozantinib arm 2	abiraterone	Subjects randomized to this arm will receive cabozantinib 20 mg daily with abiraterone and prednisone
Cabozantinib arm 2	prednisone	Subjects randomized to this arm will receive cabozantinib 20 mg daily with abiraterone and prednisone
Cabozantinib arm 3	cabozantinib	Subjects randomized to this arm will receive cabozantinb 20 mg every other day with abiraterone and prednisone
Cabozantinib arm 3	abiraterone	Subjects randomized to this arm will receive cabozantinb 20 mg every other day with abiraterone and prednisone
Cabozantinib arm 3	prednisone	Subjects randomized to this arm will receive cabozantinb 20 mg every other day with abiraterone and prednisone
Abiraterone only arm (4)	abiraterone	Subjects randomized to this arm will receive abiraterone with prednisone only
Abiraterone only arm (4)	prednisone	Subjects randomized to this arm will receive abiraterone with prednisone only

Primary Outcome Measures

Name	Time	Method
Radiographic progression free survival (PFS)	Up to 18 months	PFS is defined as the time from randomization to the earlier of the following events: disease progression or death due to any cause

Secondary Outcome Measures

Name	Time	Method

Recruitment & Eligibility