LB-S&T-13 STATISTICAL AND BIOLOGICAL EVIDENCES OF LINK BETWEEN HELICOBACTER PYLORI EXPOSURE AND PROSTATE INFLAMMATORY DISEASES

AND OBJECTIVES: Radium Ra 223 dichloride (Ra-223), an intravenous alpha-emitting radioisotope, is a calcium mimetic, forming complexes with hydroxyapatite at sites of bone metastasis for castration-resistant prostate cancer (mCRPC) patients. Abiraterone Acetate (AA), an oral androgen biosynthesis inhibitor, decreases serum testosterone for mCRPC patients. This study evaluates safety and quality of life of concurrent use of these FDA approved CRPC therapies, and is the largest cohort of subjects reported to date. METHODS: This open-label, phase II study (NCT02097303), enrolled subjects with symptomatic bone mCRPC. Subjects were assessed at baseline, day 1 of each of 6 cycles and 30 days post final Ra-223 treatment. Primary objectives were quality of life and bone pain measured by Functional Assessment of Cancer Therapy-Prostate (FACT-P) and Bone Pain Index Short Form (BPI-SF). Secondary objectives were adverse events (AE), disease progression, performance status, total alkaline phosphatase, prostate specific antigen, skeletal related events, and more antineoplastic therapy. Safety data were analyzed for all with >/1⁄4 1 infusion of Ra-223. RESULTS: 31 of 37 enrolled subjects completed the study and received Ra-223 every 4 weeks x 6 doses. + 28/37 received AA 1000 mg QD; 3/37 required dose reduction. All subjects received prednisone 5 mg BID. Median AA use before first Ra-223 dose was 31 days [95% CI 24.2-37.8]. Subjects had significant improvements in FACT-P Prostate subscales and no significant increases in pain. They reported significant pain relief from treatment. 19/31 had radiographic disease improvement or stability. Secondary endpoints also showed benefit of the combined treatment. ECOG scores remained stable. Subjects reported 72 AEs related to treatment; 44, 26, and 2 were grade 1, 2, and 3, respectively. Common AEs were fatigue and gastrointestinal issues. 4 SAEs were reported; 1 abdominal pain possibly related to AA and 3 non-related to treatment, including one death. CONCLUSIONS: This prospective trial of Radium 223 and Abiraterone Acetate confirms an overall improvement in Quality of Life, and demonstrates tolerability of synergistic use of the approved mCRPC agents. Source of Funding: Bayer Healthcare Pharmaceuticals, Inc. Statistical Analysis Provided By: Department of Data Management & Statistical Analysis, American Urological Association.