Study of Bortezomib and Dexamethasone With or Without Elotuzumab to Treat Relapsed or Refractory Multiple Myeloma

PE was planned for after at least 103 events; it was analyzed after 111 events. Response was assessed: Day 1 (± 7 days) of each cycle per modified International Myeloma Working Group (IMWG) criteria; assessed using adequate tumor assessment (ATA) (ie, serum and urine M-protein tests performed within 14 days of each other; imaging if baseline measurable extramedullary plasmacytoma existed). Progression: Any of following: Increase of 25% from lowest response in 1 or more: serum and/or urine M-component; in those without measurable serum and urine M-protein levels, difference between involved and uninvolved free light chain (FLC) levels (absolute increase > 100 mg/L); Bone marrow plasma cell percentage (≥10%). Definite new bone lesions or soft tissue plasmacytomas or definite increase in the size of existing lesions or plasmacytomas. Development of hypercalcemia attributed solely to the plasma cell proliferative disorder.

PE planned for after at least 103 events (progression/death); analyzed at 111 events. Those who neither progressed nor died were censored on the date of last adequate tumor assessment (ATA), which requires both serum and urine M-protein tests. If no post-baseline tumor assessments/no death, then censored on randomization day. Response assessed: Day 1 (± 7 days) each cycle; 30 and 60 days post treatment. Modified IMWG criteria used. Progression: Any of following: Increase of 25% in serum and/or urine M-component; if no measurable serum, urine M-protein levels, then difference between involved and uninvolved free light chain (FLC) levels (absolute increase > 100 mg/L) ; Bone marrow plasma cell percentage (≥10%). New bone lesions or soft tissue plasmacytomas or increase in size of existing lesions, plasmacytomas. Development of hypercalcemia attributed solely to plasma cell proliferative disorder. First dose occurs within 3 days of randomization.

PFS rate=Percentage probability of participants experiencing no progression or death up to 1 year, estimated using the Kaplan-Meier method. Response assessed by the investigator: Day 1 (± 7 days) of each cycle per modified IMWG criteria; assessed using ATA (ie, serum and urine M-protein tests performed within 14 days of each other; imaging done if baseline measurable extramedullary plasmacytoma existed). Progression: Any of the following: Increase of 25% from lowest response in 1 or more: serum and/or urine M-component; in those without measurable serum and urine M-protein levels, difference between involved and uninvolved FLC levels (absolute increase > 100 mg/L) ; Bone marrow plasma cell percentage (≥10%). Definite new bone lesions or soft tissue plasmacytomas or definite increase in the size of existing lesions or plasmacytomas. Development of hypercalcemia attributed solely to the plasma cell proliferative disorder.

PE was planned for after at least 103 events; it was analyzed after 111 events. Response was assessed: Day 1 (± 7 days) of each cycle per modified IMWG criteria; assessed using adequate tumor assessment (ATA) (ie, serum and urine M-protein tests performed within 14 days of each other; imaging if baseline measurable extramedullary plasmacytoma existed). Progression: Any of following: Increase of 25% from lowest response in 1 or more: serum and/or urine M-component; in those without measurable serum and urine M-protein levels, difference between involved and uninvolved FLC levels (absolute increase > 100 mg/L); Bone marrow plasma cell percentage (≥10%). Definite new bone lesions or soft tissue plasmacytomas or definite increase in the size of existing lesions or plasmacytomas. Development of hypercalcemia attributed solely to the plasma cell proliferative disorder. Randomized participants with at least 1 FcγRIIIa V allele were a sub-set of all randomized participants.

ORR was calculated for participants with a best overall response (BOR) of partial response (PR) or better, including stringent complete response (sCR), complete response (CR), and very good partial response (VGPR). BOR was determined by the investigator based on myeloma tumor assessments using IMWG criteria: CR=Negative immunofixation of serum and urine and disappearance of any soft tissue plasmacytomas, and < 5% plasma cells in bone marrow; sCR= CR + normal FLC ratio and absence of clonal cells in bone marrow; VGPR=Serum and urine M-protein detectable by immunofixation but not on electrophoresis or ≥90% reduction in serum M-protein level + urine M-protein level < 100 mg per 24 hour; PR= ≥50% reduction of serum M-protein and reduction in 24-hour urinary M-protein by ≥ 90% or to < 200 mg per 24 hour. ORR= number of participants responding divided by total number of participants randomized, measured as a percentage.

ORR was calculated for participants with a BOR of PR or better, sCR, CR, and VGPR. BOR was determined by the investigator based on myeloma tumor assessments using IMWG criteria: CR=Negative immunofixation of serum and urine and disappearance of any soft tissue plasmacytomas, and < 5% plasma cells in bone marrow; sCR= CR + normal FLC ratio and absence of clonal cells in bone marrow; VGPR=Serum and urine M-protein detectable by immunofixation but not on electrophoresis or ≥90% reduction in serum M-protein level + urine M-protein level < 100 mg per 24 hour; PR= ≥50% reduction of serum M-protein and reduction in 24-hour urinary M-protein by ≥ 90% or to < 200 mg per 24 hour. ORR= number of participants responding divided by total number of participants randomized, measured as a percentage. Randomized participants with at least 1 FcγRIIIa V allele were a sub-set of all randomized participants.