247 Background: The ALSYMPCA study (Parker, NEJM, 2013) was the basis for regulatory approval of Ra-223 for the treatment of castrate-resistant prostate cancer (CRPC) patients (pts) with symptomatic bone metastases. The aim of this prospective EAP was to monitor acute and long-term safety of Ra-223. Pt profiles and findings in the EAP setting are presented. Methods: In the EAP, CRPC pts with symptomatic bone metastases who either received or were not eligible for docetaxel received Ra-223 50 kBq/kg by injection q4wks for 6 cycles. Primary endpts: ECOG PS, symptomatic skeletal-related events (SSE), treatment-emergent adverse events [TEAEs], routine laboratory tests including PSA. Exploratory endpts: overall survival (OS), SSE rates, changes in total ALP (tALP)/PSA responses, time to tALP normalization, and to tALP and PSA progression. Descriptive statistics were used. Results: 184 pts entered treatment; baseline characteristics were similar as seen in ALSYMPCA (N=600) (exceptions in table); 67% had total A...