Study: NCT00401843

Intervention type: BIOLOGICAL
Group type: EXPERIMENTAL
Intervention: Siltuximab
Description: Siltuximab 6 mg/kg will be administered as intravenous infusion once every 2 weeks during cycle 1 in Part 1. Siltuximab 6 mg/kg will be administered as intravenous infusion once every 2 weeks during 42-day Treatment Phase and 35-day Maintenance Phase in Part 2.

Intervention type: BIOLOGICAL
Group type: EXPERIMENTAL
Intervention: Siltuximab
Description: Siltuximab 6 mg/kg will be administered as intravenous infusion once every 2 weeks during cycle 1 in Part 1. Siltuximab 6 mg/kg will be administered as intravenous infusion once every 2 weeks during 42-day Treatment Phase and 35-day Maintenance Phase in Part 2.

Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: Bortezomib
Description: Bortezomib 1.3 mg/m\^2 will be administered as intravenous bolus once every 2 weeks during cycle 1 in Part 1. Bortezomib 1.3 mg/m\^2 will be administered as intravenous bolus on Days 1, 4, 8, 11, followed by a 10-day rest period; and on Days 22, 25, 29, and 32 followed by a 10-day rest period during 42-day treatment phase in Part 2. Bortezomib 1.3 mg/m2 will be administered as intravenous bolus on Days 1, 8, 15, 22 followed by a 13-day rest period (cycle Days 23 to 35) during 35-day Maintenance Phase in Part 2.

Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: Bortezomib
Description: Bortezomib 1.3 mg/m\^2 will be administered as intravenous bolus once every 2 weeks during cycle 1 in Part 1. Bortezomib 1.3 mg/m\^2 will be administered as intravenous bolus on Days 1, 4, 8, 11, followed by a 10-day rest period; and on Days 22, 25, 29, and 32 followed by a 10-day rest period during 42-day treatment phase in Part 2. Bortezomib 1.3 mg/m2 will be administered as intravenous bolus on Days 1, 8, 15, 22 followed by a 13-day rest period (cycle Days 23 to 35) during 35-day Maintenance Phase in Part 2.

Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: Bortezomib
Description: Bortezomib 1.3 mg/m\^2 will be administered as intravenous bolus once every 2 weeks during cycle 1 in Part 1. Bortezomib 1.3 mg/m\^2 will be administered as intravenous bolus on Days 1, 4, 8, 11, followed by a 10-day rest period; and on Days 22, 25, 29, and 32 followed by a 10-day rest period during 42-day treatment phase in Part 2. Bortezomib 1.3 mg/m2 will be administered as intravenous bolus on Days 1, 8, 15, 22 followed by a 13-day rest period (cycle Days 23 to 35) during 35-day Maintenance Phase in Part 2.

Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: Placebo
Description: Matching placebo will be administered as intravenous infusion once every 2 weeks during 42-day treatment phase and 35-day maintenance phase in Part 2.

Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: Dexamethasone
Description: Dexamethasone tablet will be administered in this study at the first occurrence of documented disease progression or if bortezomib was discontinued due to intolerable toxicity. Dexamethasone 40 mg/day will be administered on days 1-4, 9-12, and 17-20 for four 28-day cycles then 40 mg/day for Days 1-4 for all subsequent cycles in treatment phase and maintenance phase of Part 2.

Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: Dexamethasone
Description: Dexamethasone tablet will be administered in this study at the first occurrence of documented disease progression or if bortezomib was discontinued due to intolerable toxicity. Dexamethasone 40 mg/day will be administered on days 1-4, 9-12, and 17-20 for four 28-day cycles then 40 mg/day for Days 1-4 for all subsequent cycles in treatment phase and maintenance phase of Part 2.