Radium-223 dichloride

SSE-FS was defined as time (months) from randomization to the earliest of onset date of skeletal symptoms treated with external beam radiotherapy (EBRT), onset date of pathological bone fracture, onset date of spinal cord compression, procedure date of tumor-related orthopedic surgery, or death from any cause. Participants who died without prior SSE and ≥ 13 weeks after the last SSE assessment are censored at the last SSE assessment date. Participants alive at the survival cut-off date are censored at the last date known to be alive. Participants with multiple events are only counted for the category in which the first event occurred. If multiple SSE (component events) occur on the same date for 1 participant, the participant is only counted into 1 category in the order of: spinal cord compression \> bone fracture \> orthopedic surgery \> EBRT.

OS is defined as the time from date of first study drug treatment to death due to any cause. Subjects still alive at the time of analysis were censored at their last date of last contact.

Safety variables to be analyzed during the treatment period include: ECOG PS, Skeletal-related events, Treatment emergent Grade 3-4 AEs, any grade of treatment-related AEs and SAEs, Safety laboratory tests including hematology and serum chemistry

Safety variables to be analyzed during the follow-up period include: Skeletal-related events, Treatment related AEs and SAEs, Secondary malignancies

Overall survival was defined as the time from date of randomization to the date of death.

Time from date of randomization to occurrence of one of the following, whichever happened earlier: 1) an on study SSE, which was defined as the use of external beam radiotherapy (EBRT) to relieve skeletal symptoms, the occurrence of new symptomatic pathological bone fractures (vertebral or nonvertebral), the occurrence of spinal cord compression, a tumor related orthopedic surgical intervention; or 2) death from any cause. Per Protocol Amendment 10, following primary analysis completion, further assessments were focused on safety, and only limited efficacy data including SSE and survival were collected and not designed to support reconsideration of the primary analysis efficacy conclusions. Accordingly, no formal statistical analyses were performed for primary and secondary efficacy outcomes in the final analysis. All primary and secondary efficacy outcome measures presented in this document came from the primary completion analysis.

Symptomatic skeletal event (SSE) free survival is based on the following events: the use of external beam radiotherapy (EBRT) to relieve skeletal symptoms; the occurrence of new symptomatic pathological bone fractures (vertebral or nonvertebral); the occurrence of spinal cord compression; a tumor related orthopedic surgical intervention, and death. In this evaluation - comparison 1, SSE-FS following randomization is defined in ITT participants as the time from randomization to an SSE or death, whichever occurs first.

In this evaluation - comparison 1, SSE-FS following randomization is defined in ITT participants as the time from randomization to an SSE or death, whichever occurs first.

Symptomatic skeletal event (SSE) free survival is based on the following events: the use of external beam radiotherapy (EBRT) to relieve skeletal symptoms; the occurrence of new symptomatic pathological bone fractures (vertebral or nonvertebral); the occurrence of spinal cord compression; a tumor related orthopedic surgical intervention, and death. In this evaluation - Comparison 2, SSE-FS from 6th dose is defined in W24 participants as the time from Week 24 baseline (the 6th dose date) to an SSE or death, whichever occurs first.

In this evaluation - Comparison 2, SSE-FS from 6th dose is defined in W24 participants as the time from Week 24 baseline (the 6th dose date) to an SSE or death, whichever occurs first.

Symptomatic skeletal event (SSE) free survival is based on the following events: the use of external beam radiotherapy (EBRT) to relieve skeletal symptoms; the occurrence of new symptomatic pathological bone fractures (vertebral or nonvertebral); the occurrence of spinal cord compression; a tumor related orthopedic surgical intervention, and death.

Symptomatic skeletal event (SSE) is defined as follows: The use of external beam radiotherapy (EBRT) to relieve skeletal symptoms; The occurrence of new symptomatic pathological bone fractures (vertebral or nonvertebral); The occurrence of spinal cord compression; A tumor related orthopedic surgical intervention.

Radiological bone scan response based on change from baseline of digitized technetium-99 bone scans using computer-aided detection software. Responder (R): 30% or greater resolution of the BSLA compared to baseline. Stable Disease (SD): Not meeting the criteria for R, PD, or UE. Progressive Disease (PD): Two or more new areas of radiotracer uptake attributable to metastatic disease in regions of bone that had not previously shown radiotracer uptake or greater than 30% increase from baseline in BSLA attributable to metastatic disease. Unable to Evaluate (UE): Assigned if bone scan results cannot be interpreted due to inconsistent image acquisition parameters compared to the reference scan, incomplete imaging, or other similar technical deficiencies.

Bone scan lesion area was defined as the sum of the pixel areas (cm2) of the set of the whole body technetium-99 bone scan imaging pixels identified as bone lesion.

PSA response; each patient will be classified as PSA responder/non-responder according to the definition of PSA response:a decrease from baseline of at least 50% maintained for at least three weeks.

SREs are defined as: Increase in pain severity index during the last week; Increase in analgesic consumption; Neurological symptoms secondary to skeletal manifestations of prostate cancer; New pathologic bone fractures (vertebral and non-vertebral); Tumour related orthopaedic surgical intervention; Subsequent external beam radiation to relieve skeletal pain; Use of radioisotopes to relieve new skeletal related symptoms; Use of corticosteroids for skeletal pain, at doses aimed for pain palliation; Use of chemotherapy, bisphosphonates, or hormones, for the treatment of skeletal disease progression

The uptake of radium-223 in bone is determined with single-photon emission tomography / computed tomography (SPECT/CT).

An adverse event (AE) is any untoward medical occurrence (i.e., any unfavorable and unintended sign \[including abnormal laboratory findings\], symptom, or disease) in a participant or clinical investigation participant after providing written informed consent for participation in the study. A treatment-emergent adverse events (TEAE) is defined as any event arising or worsening after the start of study drug administration until 30 days after the last administration of radium-223 dichloride.

TESAE occurred after the start of radium-223 dichloride treatment until 30 days after the last dose and results in death; is life-threatening; requires inpatient hospitalization or prolongs existing hospitalization; results in persistent or significant disability or incapacity; is a congenital anomaly / birth defect; is another medically important serious event as judged by the investigator; or is an occurrence of leukemia, myelodysplastic syndrome, aplastic anemia, myelofibrosis, and primary bone cancer or any other new primary malignancy, such as acute myeloid leukemia.

An adverse event (AE) is any untoward medical occurrence (i.e., any unfavorable and unintended sign \[including abnormal laboratory findings\], symptom, or disease) in a participant or clinical investigation participant after providing written informed consent for participation in the study.

Treatment-related SAE is any SAE that, according to the investigator's causality assessment, is possibly or probably related to treatment with radium-223 dichloride.

An adverse event (AE) is any untoward medical occurrence (i.e., any unfavorable and unintended sign \[including abnormal laboratory findings\], symptom, or disease) in a participant or clinical investigation participant after providing written informed consent for participation in the study. A treatment-emergent adverse events (TEAE) is defined as any event arising or worsening after the start of study drug administration until 30 days after the last administration of radium-223 dichloride.

Critical toxicities (using National Cancer Institute Common Terminology Criteria for Adverse Events (NCI-CTCAE) version 4.0) will be defined as the occurrence of one or more of the following drug-related toxicities: 1) ≥Grade 3 non-hematologic toxicity, 2) Grade 3 neutropenia with fever, 3) Grade 4 neutropenia that failed to recover to grade 2 or less after treatment with Granulocyte colony-stimulating factor (GCSF) within 2 weeks, 4) Grade 4 thrombocytopenia

DLT was defined as - Absolute neutrophil count grade greater than or equal to (\>=) 4 (Common Terminology Criteria for Adverse Events \[CTCAE\], Version 4.0: less than \[\<\] 0.5 × 109 per Liter) lasting longer than 7 days without fever despite granulocyte colony-stimulating factor (G-CSF) support). Platelet count Grade \>= 4 (CTCAE, v4.0: \< 25× 109/L) lasting longer than 7 days. Diarrhea Grade \>= 3 (CTAE, v4.0: increase of \>= 7 stools per day over baseline; incontinence; hospitalization indicated; severe increase in ostomy output compared with baseline; limiting self-care in activities of daily living) in spite of optimal use of antidiarrheal medication. Vomiting or constipation Grade \>= 4 (CTCAE, v4.0: life-threatening consequences; urgent intervention indicated). Febrile neutropenia Grade \>= 3 (CTCAE, v4.0).

Treatment-emergent adverse event (TEAEs) were defined as events that occur following the first injection of study treatment, or that started prior to the first injection and worsened during treatment. An adverse event (AE) was any untoward medical occurrence in a subject who received study drug without regard to possibility of causal relationship. An Serious Adverse Event (SAE) was an AE resulting in any of the following outcomes or deemed significant for any other reason: death; initial or prolonged in patient hospitalization; lifethreatening experience (immediate risk of dying); persistent or significant disability/incapacity; congenital anomaly. Treatment-emergent adverse events were defined as adverse events/serious adverse events that started or worsened after the study drug treatment.

In the below table, 'n' signifies those subjects who were evaluable for this measure at given time points for each group.

In the below table, 'n' signifies those subjects who were evaluable for this measure at given time points for each group.

In the below table, 'n' signifies those subjects who were evaluable for this measure at given time points for each group.

In the below table, 'n' signifies those subjects who were evaluable for this measure at given time points for each group.

In the below table, 'n' signifies those subjects who were evaluable for this measure at given time points for each group.

In the below table, 'n' signifies those subjects who were evaluable for this measure at given time points for each group.

In the below table, 'n' signifies those subjects who were evaluable for this measure at given time points for each group.

In the below table, 'n' signifies those subjects who were evaluable for this measure at given time points for each group.

In the below table, 'n' signifies those subjects who were evaluable for this measure at given time points for each group.

In the below table, 'n' signifies those subjects who were evaluable for this measure at given time points for each group.

Any physical examination finding that was classified by the investigator as a clinically significant change (compared with previous examination) was considered an AE, documented on the eCRF, and followed until the outcome was known. The below physical examination findings were recorded and reported. GDASC = General disorders and administration site conditions MND = Metabolism and nutrition disorders SSTD= Skin and subcutaneous tissue disorders MCTD = Musculoskeletal and connective tissue disorders IPPC = Injury, poisoning and procedural complications RTMD = Respiratory, thoracic and mediastinal disorders NBMU = Neoplasms benign, malignant and unspecified (include cysts and polyps) In the below table.

Long-term radiation toxicity included incidence of potential late toxicity, such as new primary cancers and bone marrow changes (acute myelogenous leukemia, myelodysplastic syndrome, and aplastic anemia).