Elotuzumab was administered IV at a dose of 10 mg/kg weekly (Days 1, 8, 15 and 22 of 4-week cycle) for the first 2 cycles and bi-weekly (every 2 weeks) (Day 1 and Day 15) thereafter until disease progression or unacceptable toxicity became apparent. Lenalidomide 25 mg was administered PO once daily for the first 3 weeks of each 4-week cycle. The dose of lenalidomide was administered at least 2-4 hours after completion of elotuzumab infusion. On weeks without elotuzumab administration, dexamethasone was administered PO as a single dose of 40 mg. On weeks of elotuzumab infusion, the weekly dose of dexamethasone was administered as a split dose of: 28 mg PO (between 3 to 24 hours prior to the start of the elotuzumab infusion) and 8 mg IV (At least 45 min prior to the start of the elotuzumab infusion).

Elotuzumab was administered IV at a dose of 20 mg/kg weekly (Days 1, 8, 15 and 22 of 4-week cycle) for the first 2 cycles and bi-weekly (every 2 weeks) (Day 1 and Day 15) thereafter until disease progression or unacceptable toxicity became apparent. Lenalidomide 25 mg was administered PO once daily for the first 3 weeks of each 4-week cycle. The dose of lenalidomide was administered at least 2-4 hours after completion of elotuzumab infusion. On weeks without elotuzumab administration, dexamethasone was administered PO as a single dose of 40 mg. On weeks of elotuzumab infusion, the weekly dose of dexamethasone was administered as a split dose of: 28 mg PO (between 3 to 24 hours prior to the start of the elotuzumab infusion) and 8 mg IV (At least 45 min prior to the start of the elotuzumab infusion).

Elotuzumab was administered IV at a dose of 10 mg/kg weekly (Days 1, 8, 15 and 22 of 4-week cycle) for the first 2 cycles and bi-weekly (every 2 weeks) (Day 1 and Day 15) thereafter until disease progression or unacceptable toxicity became apparent. Lenalidomide 25 mg was administered PO once daily for the first 3 weeks of each 4-week cycle. The dose of lenalidomide was administered at least 2-4 hours after completion of elotuzumab infusion. On weeks without elotuzumab administration, dexamethasone was administered PO as a single dose of 40 mg. On weeks of elotuzumab infusion, the weekly dose of dexamethasone was administered as a split dose of: 28 mg PO (between 3 to 24 hours prior to the start of the elotuzumab infusion) and 8 mg IV (At least 45 min prior to the start of the elotuzumab infusion).

Elotuzumab was administered IV at a dose of 20 mg/kg weekly (Days 1, 8, 15 and 22 of 4-week cycle) for the first 2 cycles and bi-weekly (every 2 weeks) (Day 1 and Day 15) thereafter until disease progression or unacceptable toxicity became apparent. Lenalidomide 25 mg was administered PO once daily for the first 3 weeks of each 4-week cycle. The dose of lenalidomide was administered at least 2-4 hours after completion of elotuzumab infusion. On weeks without elotuzumab administration, dexamethasone was administered PO as a single dose of 40 mg. On weeks of elotuzumab infusion, the weekly dose of dexamethasone was administered as a split dose of: 28 mg PO (between 3 to 24 hours prior to the start of the elotuzumab infusion) and 8 mg IV (At least 45 min prior to the start of the elotuzumab infusion).

Elotuzumab was administered IV at a dose of 10 mg/kg weekly (Days 1, 8, 15 and 22 of 4-week cycle) for the first 2 cycles and bi-weekly (every 2 weeks) (Day 1 and Day 15) thereafter until disease progression or unacceptable toxicity became apparent. Lenalidomide 25 mg was administered PO once daily for the first 3 weeks of each 4-week cycle. The dose of lenalidomide was administered at least 2-4 hours after completion of elotuzumab infusion. On weeks without elotuzumab administration, dexamethasone was administered PO as a single dose of 40 mg. On weeks of elotuzumab infusion, the weekly dose of dexamethasone was administered as a split dose of: 28 mg PO (between 3 to 24 hours prior to the start of the elotuzumab infusion) and 8 mg IV (At least 45 min prior to the start of the elotuzumab infusion).

Elotuzumab was administered IV at a dose of 20 mg/kg weekly (Days 1, 8, 15 and 22 of 4-week cycle) for the first 2 cycles and bi-weekly (every 2 weeks) (Day 1 and Day 15) thereafter until disease progression or unacceptable toxicity became apparent. Lenalidomide 25 mg was administered PO once daily for the first 3 weeks of each 4-week cycle. The dose of lenalidomide was administered at least 2-4 hours after completion of elotuzumab infusion. On weeks without elotuzumab administration, dexamethasone was administered PO as a single dose of 40 mg. On weeks of elotuzumab infusion, the weekly dose of dexamethasone was administered as a split dose of: 28 mg PO (between 3 to 24 hours prior to the start of the elotuzumab infusion) and 8 mg IV (At least 45 min prior to the start of the elotuzumab infusion).

Elotuzumab was administered IV at a dose of 10 mg/kg weekly (Days 1, 8, 15 and 22 of 4-week cycle) for the first 2 cycles and bi-weekly (every 2 weeks) (Day 1 and Day 15) thereafter until disease progression or unacceptable toxicity became apparent. Lenalidomide 25 mg was administered PO once daily for the first 3 weeks of each 4-week cycle. The dose of lenalidomide was administered at least 2-4 hours after completion of elotuzumab infusion. On weeks without elotuzumab administration, dexamethasone was administered PO as a single dose of 40 mg. On weeks of elotuzumab infusion, the weekly dose of dexamethasone was administered as a split dose of: 28 mg PO (between 3 to 24 hours prior to the start of the elotuzumab infusion) and 8 mg IV (At least 45 min prior to the start of the elotuzumab infusion).

Elotuzumab was administered IV at a dose of 20 mg/kg weekly (Days 1, 8, 15 and 22 of 4-week cycle) for the first 2 cycles and bi-weekly (every 2 weeks) (Day 1 and Day 15) thereafter until disease progression or unacceptable toxicity became apparent. Lenalidomide 25 mg was administered PO once daily for the first 3 weeks of each 4-week cycle. The dose of lenalidomide was administered at least 2-4 hours after completion of elotuzumab infusion. On weeks without elotuzumab administration, dexamethasone was administered PO as a single dose of 40 mg. On weeks of elotuzumab infusion, the weekly dose of dexamethasone was administered as a split dose of: 28 mg PO (between 3 to 24 hours prior to the start of the elotuzumab infusion) and 8 mg IV (At least 45 min prior to the start of the elotuzumab infusion).

Elotuzumab was administered IV at a dose of 10 mg/kg weekly (Days 1, 8, 15 and 22 of 4-week cycle) for the first 2 cycles and bi-weekly (every 2 weeks) (Day 1 and Day 15) thereafter until disease progression or unacceptable toxicity became apparent. Lenalidomide 25 mg was administered PO once daily for the first 3 weeks of each 4-week cycle. The dose of lenalidomide was administered at least 2-4 hours after completion of elotuzumab infusion. On weeks without elotuzumab administration, dexamethasone was administered PO as a single dose of 40 mg. On weeks of elotuzumab infusion, the weekly dose of dexamethasone was administered as a split dose of: 28 mg PO (between 3 to 24 hours prior to the start of the elotuzumab infusion) and 8 mg IV (At least 45 min prior to the start of the elotuzumab infusion).

Elotuzumab was administered IV at a dose of 20 mg/kg weekly (Days 1, 8, 15 and 22 of 4-week cycle) for the first 2 cycles and bi-weekly (every 2 weeks) (Day 1 and Day 15) thereafter until disease progression or unacceptable toxicity became apparent. Lenalidomide 25 mg was administered PO once daily for the first 3 weeks of each 4-week cycle. The dose of lenalidomide was administered at least 2-4 hours after completion of elotuzumab infusion. On weeks without elotuzumab administration, dexamethasone was administered PO as a single dose of 40 mg. On weeks of elotuzumab infusion, the weekly dose of dexamethasone was administered as a split dose of: 28 mg PO (between 3 to 24 hours prior to the start of the elotuzumab infusion) and 8 mg IV (At least 45 min prior to the start of the elotuzumab infusion).

Elotuzumab was administered IV at a dose of 10 mg/kg weekly (Days 1, 8, 15 and 22 of 4-week cycle) for the first 2 cycles and bi-weekly (every 2 weeks) (Day 1 and Day 15) thereafter until disease progression or unacceptable toxicity became apparent. Lenalidomide 25 mg was administered PO once daily for the first 3 weeks of each 4-week cycle. The dose of lenalidomide was administered at least 2-4 hours after completion of elotuzumab infusion. On weeks without elotuzumab administration, dexamethasone was administered PO as a single dose of 40 mg. On weeks of elotuzumab infusion, the weekly dose of dexamethasone was administered as a split dose of: 28 mg PO (between 3 to 24 hours prior to the start of the elotuzumab infusion) and 8 mg IV (At least 45 min prior to the start of the elotuzumab infusion).

Elotuzumab was administered IV at a dose of 20 mg/kg weekly (Days 1, 8, 15 and 22 of 4-week cycle) for the first 2 cycles and bi-weekly (every 2 weeks) (Day 1 and Day 15) thereafter until disease progression or unacceptable toxicity became apparent. Lenalidomide 25 mg was administered PO once daily for the first 3 weeks of each 4-week cycle. The dose of lenalidomide was administered at least 2-4 hours after completion of elotuzumab infusion. On weeks without elotuzumab administration, dexamethasone was administered PO as a single dose of 40 mg. On weeks of elotuzumab infusion, the weekly dose of dexamethasone was administered as a split dose of: 28 mg PO (between 3 to 24 hours prior to the start of the elotuzumab infusion) and 8 mg IV (At least 45 min prior to the start of the elotuzumab infusion).

Elotuzumab 10 mg/kg was intravenously (IV) given weekly (Days 1, 8, 15 and 22 of 4-week cycle) for the first 2 cycles and bi-weekly (every 2 weeks) (Day 1 and Day 15) thereafter until disease progression or unacceptable toxicity. Elotuzumab was first given at 10 mg/kg. If all participants completed the first cycle and none experienced a dose limiting toxicity (DLT), the dose was escalated to 20 mg/kg. If 1 experienced a DLT at 10 mg/kg, 3 additional participants were assigned to 10 mg/kg. If no additional participants experienced a DLT, the dose was escalated to 20 mg/kg. Lenalidomide 25 mg was administered orally once daily for the first 3 weeks of each 4-week cycle. On weeks without elotuzumab, dexamethasone was administered as a single oral (PO) dose of 40 mg. On weeks of elotuzumab infusion, the weekly dose of dexamethasone was administered as a split dose of: 28 mg PO (3 to 24 hours prior to the start of elotuzumab) and 8 mg IV (45 min prior to start of elotuzumab).

Elotuzumab 20 mg/kg was intravenously (IV) given weekly (Days 1, 8, 15 and 22 of 4-week cycle) for the first 2 cycles and bi-weekly (every 2 weeks) (Day 1 and Day 15) thereafter until disease progression or unacceptable toxicity. Elotuzumab was first given at 10 mg/kg. If all participants completed the first cycle and none experienced a dose limiting toxicity (DLT), the dose was escalated to 20 mg/kg. If 1 experienced a DLT at 10 mg/kg, 3 additional participants were assigned to 10 mg/kg. If no additional participants experienced a DLT, the dose was escalated to 20 mg/kg. Lenalidomide 25 mg was administered orally once daily for the first 3 weeks of each 4-week cycle. On weeks without elotuzumab, dexamethasone was administered as a single oral (PO) dose of 40 mg. On weeks of elotuzumab infusion, the weekly dose of dexamethasone was administered as a split dose of: 28 mg PO (3 to 24 hours prior to the start of elotuzumab) and 8 mg IV (45 min prior to start of elotuzumab).

Elotuzumab was administered IV at a dose of 10 mg/kg weekly (Days 1, 8, 15 and 22 of 4-week cycle) for the first 2 cycles and bi-weekly (every 2 weeks) (Day 1 and Day 15) thereafter until disease progression or unacceptable toxicity became apparent. Lenalidomide 25 mg was administered PO once daily for the first 3 weeks of each 4-week cycle. The dose of lenalidomide was administered at least 2-4 hours after completion of elotuzumab infusion. On weeks without elotuzumab administration, dexamethasone was administered PO as a single dose of 40 mg. On weeks of elotuzumab infusion, the weekly dose of dexamethasone was administered as a split dose of: 28 mg PO (between 3 to 24 hours prior to the start of the elotuzumab infusion) and 8 mg IV (At least 45 min prior to the start of the elotuzumab infusion).

Elotuzumab was administered IV at a dose of 20 mg/kg weekly (Days 1, 8, 15 and 22 of 4-week cycle) for the first 2 cycles and bi-weekly (every 2 weeks) (Day 1 and Day 15) thereafter until disease progression or unacceptable toxicity became apparent. Lenalidomide 25 mg was administered PO once daily for the first 3 weeks of each 4-week cycle. The dose of lenalidomide was administered at least 2-4 hours after completion of elotuzumab infusion. On weeks without elotuzumab administration, dexamethasone was administered PO as a single dose of 40 mg. On weeks of elotuzumab infusion, the weekly dose of dexamethasone was administered as a split dose of: 28 mg PO (between 3 to 24 hours prior to the start of the elotuzumab infusion) and 8 mg IV (At least 45 min prior to the start of the elotuzumab infusion).