Defined as the time from the date of randomization to the date of first documented PD per International Myeloma Working Group (IMWG) criteria by Independent Review Committee (IRC) or death from any cause in the absence of progression, whichever occurs first.

Defined as achieving MRD negativity at 10\^-5 sensitivity threshold (1 nucleated tumor cell in 100,000 normal cells) assessed by next-generation sequencing (NGS) at least once during the time of confirmed complete response (CR) or better response per IMWG criteria by IRC.

PFS is defined as time from randomization until earliest date of disease progression (PD), determined by Independent Review Committee (IRC), according to the International Myeloma Working Group (IMWG) Response Criteria, or death due to any cause. PD is defined as increase of \>=25% from lowest value in \>=1 of following (serum M-protein \[absolute increase \>=0.5 grams per deciliter {g/dL}\]; serum M-protein increase \>=1g/dL \[when lowest M-protein \>=5g/dL\]; urine M-protein \[absolute increase \>=200 milligrams per 24 hours {mg/24h}\]; participants without measurable serum \& urine M-protein levels, difference between involved \& uninvolved serum free light chains (sFLC) levels \[absolute increase \>10mg/dL\]; appearance of new lesion,\>=50% increase from nadir in Sum of the products of the maximal perpendicular diameters of measured lesions (SPD) of \>1 lesion, or \>=50% increase in longest diameter of previous lesion \>1 centimeter (cm) in short axis.

PFS is time from randomization until earliest date of progressive disease (PD), or death due to any cause per investigator-assessed response per IMWG. PD is ≥25% increase from nadir in any of following: serum M-protein (absolute increase ≥0.5 gram per deciliter \[g/dL\]),urine M-protein(absolute increase ≥200 mg/24hr),difference between involved/uninvolved FLC levels (absolute increase \>10 mg/dL) in patients without measurable serum and urine M-protein levels, or bone marrow plasma-cell percentage irrespective of baseline status (absolute increase ≥10%) in patients without measurable serum and urine M-protein levels and without measurable involved FLC levels; appearance of new lesion,≥50% increase in longest diameter of a lesion previously measured \>1cm in short axis, or ≥50% increase from nadir in sum of products of two longest perpendicular diameters of more than 1 lesion; ≥50% increase in circulating plasma cells (minimum of 200 cells/microliter) if this is only measure of disease.

KVA scale ranges from 0 to 4 with higher score indicating greater severity of corneal events.

KVA scale ranges from 0 to 4 with higher score indicating greater severity of corneal events.

KVA scale ranges from 0 to 4 with higher score indicating greater severity of corneal events. Data will be presented for the total number of participants with corneal events in each study group during 6 to 12 months.

The overall CHR rate is defined as the proportion of participants who achieve a CHR during or after study treatment initiation, as assessed by the investigator, according to the consensus guidelines for AL amyloidosis.

ORR is defined as the percentage of participants with a confirmed partial response \[PR\] or better (i.e., PR, very good partial response (VGPR), complete response \[CR\], stringent complete response \[sCR\]). Responses will be assessed using International Myeloma Working Group (IMWG) criteria.

The KVA scale is based on the evaluation of corneal changes using slit lamp examination. This scale provides a standardized approach for evaluating the relationship between corneal health and visual acuity. KVA scale is defined as Grade 0: No keratopathy, normal visual acuity with no corneal abnormalities; Grade 1: Mild changes to the cornea with no significant loss in visual acuity; Grade 2: Moderate corneal changes with noticeable visual acuity reduction; Grade 3: Severe corneal changes with substantial visual acuity impairment; Grade 4: Very severe corneal changes leading to significant vision loss. Higher grade indicates greater severity of corneal events.

Criteria for dose-limiting toxicity (DLT) included hematologic indicators such as Grade 3-5 febrile neutropenia and thrombocytopenia with bleeding. Non-hematologic criteria, excluding corneal toxicity, comprise Grade 3-5 toxicities, with exceptions for manageable nausea, vomiting, or diarrhea, controlled Grade 3 hypertension, and events linked to disease progression. Tumor lysis syndrome (TLS) of Grade 3 or 4, successfully managed within 7 days without end-organ damage, is considered. Corneal toxicity, assessed by the GSK corneal grading scale at Grade 4, is a DLT. Other organ-specific toxicities, notably liver toxicity meeting GSK stopping criteria, also qualify as DLT severity was graded using National Cancer Institute (NCI) - Common Terminology Criteria for Adverse Events (CTCAE) (version 5.0).

An AE is any untoward medical occurrence in a clinical investigation participant, temporally associated with the use of a medicinal product, whether or not considered related to the medicinal product. AEs were coded using the Medical Dictionary for Regulatory Activities (MedDRA) coding system.

Blood samples were collected for the analysis of hematology parameters. The laboratory parameters were graded according to CTCAE version 5. Grade 1 (G1): mild; Grade 2 (G2): moderate; Grade 3 (G3): severe; Grade 4 (G4) life-threatening or disabling. Higher grade indicates greater severity and an increase in CTCAE grade was defined relative to the Baseline grade. Any worst-case post baseline increase to G1, G2, G3, and G4 are presented. Baseline value was defined as the most recent, non-missing value from a local laboratory prior to the first dose of study treatment.

Blood samples were collected for the analysis of chemistry parameters. The laboratory parameters were graded according to CTCAE version 5. G1: mild; G2: moderate; G3: severe; Grade 4 (G4) life-threatening or disabling. Higher grade indicates greater severity and an increase in CTCAE grade was defined relative to the Baseline grade. Any worst-case post baseline increase to G1, G2, G3, and G4 are presented. Baseline value was defined as the most recent, non-missing value from a local laboratory prior to the first dose of study treatment. CPK = creatine kinase.

Overall Response Rate (ORR) was defined as the percentage of participants with a confirmed Partial Response (PR) or better as the best overall response (i.e., PR, Very Good Partial Response \[VGPR\], Complete Response \[CR\], and stringent Complete Response \[sCR\]), as assessed by the investigator per international myeloma working group (IMWG) (2016). PR is defined as ≥50% reduction of serum M-protein and reduction in 24-hour urinary M-protein by ≥90% or to \<200 mg/24 h. VGPR is defined as serum and urine M-component detectable by immunofixation but not on electrophoresis OR ≥ 90% reduction in serum M-component plus urine M-component \<100 mg/24 h. CR is defined as negative immunofixation of serum and urine AND disappearance of any soft tissue plasmacytomas AND \<5% plasmacytomas in the bone marrow. sCR is defined as CR as above PLUS normal serum free light-chain (FLC) assay ratio and absence of clonal cells in bone marrow by immunohistochemistry or immunofluorescence.

Criteria for dose-limiting toxicity (DLT) included hematologic indicators such as Grade 3-5 febrile neutropenia and thrombocytopenia with bleeding. Non-hematologic criteria, excluding corneal toxicity, comprise Grade 3-5 toxicities, with exceptions for manageable nausea, vomiting, or diarrhea, controlled Grade 3 hypertension, and events linked to disease progression. Tumor lysis syndrome (TLS) of Grade 3 or 4, successfully managed within 7 days without end-organ damage, is considered. Corneal toxicity, assessed by the GSK corneal grading scale at Grade 4, is a DLT. Other organ-specific toxicities, notably liver toxicity meeting GSK stopping criteria, also qualify as DLT severity was graded using National Cancer Institute (NCI) - Common Terminology Criteria for Adverse Events (CTCAE) Version (v) 5.0.

Overall Response Rate (ORR) was defined as the percentage of participants with a confirmed Partial Response (PR) or better as the best overall response (i.e., PR, Very Good Partial Response \[VGPR\], Complete Response \[CR\], and stringent Complete Response \[sCR\]), as assessed by the investigator per international myeloma working group (IMWG) (2016). PR is defined as ≥50% reduction of serum M-protein and reduction in 24-hour urinary M-protein by ≥90% or to \<200 mg/24 h. VGPR is defined as serum and urine M-component detectable by immunofixation but not on electrophoresis OR ≥ 90% reduction in serum M-component plus urine M-component \<100 mg/24 h. CR is defined as negative immunofixation of serum and urine AND disappearance of any soft tissue plasmacytomas AND \<5% plasmacytomas in the bone marrow. sCR is defined as CR as above PLUS normal serum free light-chain (FLC) assay ratio and absence of clonal cells in bone marrow by immunohistochemistry or immunofluorescence.

Blood samples were collected for PK analysis of belantamab mafodotin ADC. As pre-specified in protocol, only specified treatment arms were planned to be analyzed for this outcome measure. As first dose of belantamab mafodotin was administered on Day 1, cycle length correlates to Day 1 plus 21 days i.e., Day 22 in timeframe. Only those participants who were measured and analyzed (i.e., contributed to data reported in the table) were included in the Overall Number of Participants Analyzed field. 'Number Analyzed' signifies participants evaluable for the specified timepoints.

Blood samples were collected for PK analysis of belantamab mafodotin ADC. As pre-specified in protocol, only specified treatment arms were planned to be analyzed for this outcome measure. As first dose of belantamab mafodotin was administered on Day 1, cycle length correlates to Day 1 plus 21 days i.e., Day 22 in timeframe.

Blood samples were collected for PK analysis of belantamab mafodotin ADC. As pre-specified in protocol, only specified treatment arms were planned to be analyzed for this outcome measure.

Blood samples were collected for PK analysis of belantamab mafodotin ADC. As pre-specified in protocol, only specified treatment arms were planned to be analyzed for this outcome measure. As first dose of belantamab mafodotin was administered on Day 1, cycle length correlates to Day 1 plus 21 days i.e., Day 22 in timeframe.

Blood samples were collected for PK analysis of belantamab mafodotin ADC. As pre-specified in protocol, only specified treatment arms were planned to be analyzed for this outcome measure. As first dose of belantamab mafodotin was administered on Day 1, cycle length correlates to Day 1 plus 21 days i.e., Day 22 in timeframe.

Blood samples were collected for PK analysis of belantamab mafodotin ADC. As pre-specified in protocol, only specified treatment arms were planned to be analyzed for this outcome measure. As first dose of belantamab mafodotin was administered on Day 1, cycle length correlates to Day 1 plus 21 days i.e., Day 22 in timeframe.

Blood samples were collected for PK analysis of belantamab mafodotin ADC. As pre-specified in protocol, only specified treatment arms were planned to be analyzed for this outcome measure. As first dose of belantamab mafodotin was administered on Day 1, cycle length correlates to Day 1 plus 21 days i.e., Day 22 in timeframe. For some participants, dosing in Cycle 2 or Cycle 4 was delayed, resulting in the pre-dose samples in these cycles (C2D1 or C4D1) being collected later than the protocol-defined planned days after dosing in C1D1 or C3D1. Consequently, the last PK samples for these participants were collected outside the pre-defined protocol time points, and certain Tlast values in the data table extend beyond the original protocol-defined Time Frame.

Blood samples were collected for PK analysis of belantamab mafodotin Total Antibody. As pre-specified in protocol, only specified treatment arms were planned to be analyzed for this outcome measure. As first dose of belantamab mafodotin was administered on Day 1, cycle length correlates to Day 1 plus 21 days i.e., Day 22 in timeframe.

Blood samples were collected for PK analysis of belantamab mafodotin total Antibody. As pre-specified in protocol, only specified treatment arms were planned to be analyzed for this outcome measure. As first dose of belantamab mafodotin was administered on Day 1, cycle length correlates to Day 1 plus 21 days i.e., Day 22 in timeframe.

Blood samples were collected for PK analysis of belantamab mafodotin Total Antibody. As pre-specified in protocol, only specified treatment arms were planned to be analyzed for this outcome measure.

Blood samples were collected for PK analysis of belantamab mafodotin Total Antibody. As pre-specified in protocol, only specified treatment arms were planned to be analyzed for this outcome measure. As first dose of belantamab mafodotin was administered on Day 1, cycle length correlates to Day 1 plus 21 days i.e., Day 22 in timeframe.

Blood samples were collected for PK analysis of belantamab mafodotin total antibody. As pre-specified in protocol, only specified treatment arms were planned to be analyzed for this outcome measure. As first dose of belantamab mafodotin was administered on Day 1, cycle length correlates to Day 1 plus 21 days i.e., Day 22 in timeframe.

Blood samples were collected for PK analysis of belantamab mafodotin Total Antibody. As pre-specified in protocol, only specified treatment arms were planned to be analyzed for this outcome measure. As first dose of belantamab mafodotin was administered on Day 1, cycle length correlates to Day 1 plus 21 days i.e., Day 22 in timeframe.

Blood samples were collected for PK analysis of belantamab mafodotin Total Antibody. As pre-specified in protocol, only specified treatment arms were planned to be analyzed for this outcome measure. As first dose of belantamab mafodotin was administered on Day 1, cycle length correlates to Day 1 plus 21 days i.e., Day 22 in timeframe. For some participants, dosing in Cycle 2 or Cycle 4 was delayed, resulting in the pre-dose samples in these cycles (C2D1 or C4D1) being collected later than the protocol-defined planned days after dosing in C1D1 or C3D1. Consequently, the last PK samples for these participants were collected outside the pre-defined protocol time points, and certain Tlast values in the data table extend beyond the original protocol-defined Time Frame.

Blood samples were collected for PK analysis of belantamab mafodotin Cys-mcMMAF. As pre-specified in protocol, only specified treatment arms were planned to be analyzed for this outcome measure. As first dose of belantamab mafodotin was administered on Day 1, cycle length correlates to Day 1 plus 21 days i.e., Day 22 in timeframe.

Blood samples were collected for PK analysis of belantamab mafodotin Cys-mcMMAF. As pre-specified in protocol, only specified treatment arms were planned to be analyzed for this outcome measure. In cases where the nominal Day 8 sample was collected prior to 168 hours and earlier time points did not permit reliable extrapolation to 168 hours, a later sample (e.g., Day 15) with a measurable concentration was used to support estimation of the concentration at 168 hours. Outcome data are reported only for AUC over 0-168 hours.

Blood samples were collected for PK analysis of belantamab mafodotin Cys-mcMMAF. As pre-specified in protocol, only specified treatment arms were planned to be analyzed for this outcome measure.

Blood samples were collected for PK analysis of belantamab mafodotin Cys-mcMMAF. As pre-specified in protocol, only specified treatment arms were planned to be analyzed for this outcome measure. As first dose of belantamab mafodotin was administered on Day 1, cycle length correlates to Day 1 plus 21 days i.e., Day 22 in timeframe.

Blood samples were collected for PK analysis of belantamab mafodotin Cys-mcMMAF. As pre-specified in protocol, only specified treatment arms were planned to be analyzed for this outcome measure. As first dose of belantamab mafodotin was administered on Day 1, cycle length correlates to Day 1 plus 21 days i.e., Day 22 in timeframe.

Blood samples were collected for PK analysis of belantamab mafodotin Cys-mcMMAF. As pre-specified in protocol, only specified treatment arms were planned to be analyzed for this outcome measure. As first dose of belantamab mafodotin was administered on Day 1, cycle length correlates to Day 1 plus 21 days i.e., Day 22 in timeframe.

Blood samples were collected for PK analysis of belantamab mafodotin ADC. As first dose of belantamab mafodotin was administered on Day 1, cycle length correlates to Day 1 plus 21 days i.e., Day 22 in timeframe.

Blood samples were collected for PK analysis of belantamab mafodotin ADC. As first dose of belantamab mafodotin was administered on Day 1, cycle length correlates to Day 1 plus 21 days i.e., Day 22 in timeframe.

Blood samples were collected for PK analysis of belantamab mafodotin ADC.

Blood samples were collected for PK analysis of belantamab mafodotin ADC. As first dose of belantamab mafodotin was administered on Day 1, cycle length correlates to Day 1 plus 21 days i.e., Day 22 in timeframe.

Blood samples were collected for PK analysis of belantamab mafodotin ADC. As first dose of belantamab mafodotin was administered on Day 1, cycle length correlates to Day 1 plus 21 days i.e., Day 22 in timeframe.

Blood samples were collected for PK analysis of belantamab mafodotin ADC. As first dose of belantamab mafodotin was administered on Day 1, cycle length correlates to Day 1 plus 21 days i.e., Day 22 in timeframe.

Blood samples were collected for PK analysis of belantamab mafodotin ADC. As first dose of belantamab mafodotin was administered on Day 1, cycle length correlates to Day 1 plus 21 days i.e., Day 22 in timeframe. For some participants, dosing in Cycle 2 or Cycle 4 was delayed, resulting in the pre-dose samples in these cycles (C2D1 or C4D1) being collected later than the protocol-defined planned days after dosing in C1D1 or C3D1. Consequently, the last PK samples for these participants were collected outside the pre-defined protocol time points, and certain Tlast values in the data table extend beyond the original protocol-defined Time Frame.

Blood samples were collected for PK analysis of belantamab mafodotin Total Antibody. As first dose of belantamab mafodotin was administered on Day 1, cycle length correlates to Day 1 plus 21 days i.e., Day 22 in timeframe.

Blood samples were collected for PK analysis of belantamab mafodotin Total Antibody. As first dose of belantamab mafodotin was administered on Day 1, cycle length correlates to Day 1 plus 21 days i.e., Day 22 in timeframe.

Blood samples were collected for PK analysis of belantamab mafodotin Total Antibody.

Blood samples were collected for PK analysis of belantamab mafodotin Total Antibody. As first dose of belantamab mafodotin was administered on Day 1, cycle length correlates to Day 1 plus 21 days i.e., Day 22 in timeframe.

Blood samples were collected for PK analysis of belantamab mafodotin Total Antibody. As first dose of belantamab mafodotin was administered on Day 1, cycle length correlates to Day 1 plus 21 days i.e., Day 22 in timeframe.

Blood samples were collected for PK analysis of belantamab mafodotin Total Antibody. As first dose of belantamab mafodotin was administered on Day 1, cycle length correlates to Day 1 plus 21 days i.e., Day 22 in timeframe.

Blood samples were collected for PK analysis of belantamab mafodotin Total Antibody. As first dose of belantamab mafodotin was administered on Day 1, cycle length correlates to Day 1 plus 21 days i.e., Day 22 in timeframe. For some participants, dosing in Cycle 2 or Cycle 4 was delayed, resulting in the pre-dose samples in these cycles (C2D1 or C4D1) being collected later than the protocol-defined planned days after dosing in C1D1 or C3D1. Consequently, the last PK samples for these participants were collected outside the pre-defined protocol time points, and certain Tlast values in the data table extend beyond the original protocol-defined Time Frame.

Blood samples were collected for PK analysis of belantamab mafodotin Cys-mcMMAF. As first dose of belantamab mafodotin was administered on Day 1, cycle length correlates to Day 1 plus 21 days i.e., Day 22 in timeframe.

Blood samples were collected for PK analysis of belantamab mafodotin Cys-mcMMAF. In cases where the nominal Day 8 sample was collected prior to 168 hours and earlier time points did not permit reliable extrapolation to 168 hours, a later sample (e.g., Day 15) with a measurable concentration was used to support estimation of the concentration at 168 hours. Outcome data are reported only for AUC over 0-168 hours.

Blood samples were collected for PK analysis of belantamab mafodotin Cys-mcMMAF.

Blood samples were collected for PK analysis of belantamab mafodotin Cys-mcMMAF. As first dose of belantamab mafodotin was administered on Day 1, cycle length correlates to Day 1 plus 21 days i.e., Day 22 in timeframe.

Blood samples were collected for PK analysis of belantamab mafodotin Cys-mcMMAF. As first dose of belantamab mafodotin was administered on Day 1, cycle length correlates to Day 1 plus 21 days i.e., Day 22 in timeframe.

Blood samples were collected for PK analysis of belantamab mafodotin Cys-mcMMAF. As first dose of belantamab mafodotin was administered on Day 1, cycle length correlates to Day 1 plus 21 days i.e., Day 22 in timeframe.

The number of participants with DLTs will be reported.

AEs and SAEs will be collected.

An AE is any untoward medical occurrence in a clinical study participant, temporally associated with the use of a study intervention, whether or not considered related to the study intervention.

An SAE is defined as any untoward medical occurrence that, at any dose: results in death; is life threatening; requires inpatient hospitalization or prolongation of existing hospitalization; results in persistent disability/incapacity; is a congenital anomaly/birth defect; important medical events that may jeopardize the participant or may require medical or surgical intervention; is associated with liver injury and impaired liver function.

An event was considered DLT if it occurred within 21 days of treatment and met any of the following criteria within same period: * Any Grade (Gr.) 3 or greater non-hematologic toxicity as described in NCI-CTCAE Version 5.0, other than corneal events that persists for \>48 hours despite supportive treatment or leads to hospitalization. * Hematologic toxicity such as Gr. 3 or greater febrile neutropenia lasting \>48 hours despite adequate treatment (Gr. 3 defined as absolute neutrophil count (ANC) \<1000/millimeter cube (mm\^3) at a single temperature \>38.3 degree celsius or a sustained temperature \>=38 degree celsius for more than 1 hour) and, Gr. 4 thrombocytopenia defined as platelet count \<25000/mm\^3 with clinically significant bleeding, or if platelet transfusion is required. * Gr. 4 per the corneal grading scale. * Liver toxicity meeting pre-specified by GSK liver stopping criteria.

Criteria for dose-limiting toxicity (DLT) included hematologic indicators such as Grade 3-5 febrile neutropenia and thrombocytopenia with bleeding. Non-hematologic criteria, excluding corneal toxicity, comprise Grade 3-5 toxicities, with exceptions for manageable nausea, vomiting, or diarrhea, controlled Grade 3 hypertension, and events linked to disease progression. Tumor lysis syndrome (TLS) of Grade 3 or 4, successfully managed within 7 days without end-organ damage, is considered. Corneal toxicity, assessed by the GSK corneal grading scale at Grade 4, is a DLT. Other organ-specific toxicities, notably liver toxicity meeting GSK stopping criteria, also qualify as DLT severity was graded using National Cancer Institute (NCI) - Common Terminology Criteria for Adverse Events (CTCAE) version (v) 5.0.

Number of Participants who passed screening and were randomized across sub studies are presented.

An AE is any untoward medical occurrence in a clinical investigation participant, temporally associated with the use of a medicinal product, whether or not considered related to the medicinal product. SAE is defined as any untoward medical occurrence that, at any dose results in death, is life-threatening, requires hospitalization or prolongation of existing hospitalization, results in disability/incapacity, is a congenital anomaly/birth defect, other situations which involve medical or scientific judgment or is associated with liver injury and impaired liver function.

DLT is an AE that is considered by the investigator to be clinically relevant and attributed to the study therapy during the 21 day DLT period and meets at least one of the DLT criteria: any Grade 4 and 3 non-hematologic toxicity, any Grade 3 or greater non-hematologic laboratory value, hematologic toxicity lasting \>=7 days, except Grade 4 thrombocytopenia of any duration or Grade 3 thrombocytopenia associated with clinically significant bleeding. Grade 3 or greater febrile neutropenia lasting \>48 hours (h) despite adequate treatment, Nephrotoxicity requiring dialysis, Liver toxicity, prolonged delay (\>14 days) in initiating Cycle 2 due to any treatment (pembrolizumab or GSK2857916) related toxicity, any treatment-related toxicity that causes discontinuation of treatment during Cycle 1, any other toxicity considered to be dose-limiting that occurs beyond 21 days and any other event which in the judgment of the investigator and GlaxoSmithKline Medical Monitor is considered to be a DLT.

Blood samples were collected for the analysis of following hematology parameters: hemoglobin, White blood cells (WBC) count, lymphocytes, neutrophils and platelet count. The laboratory parameters were graded according to National Cancer Institute-Common Terminology Criteria for Adverse Events (NCI-CTCAE) version 4.03. Grade 1: mild; Grade 2: moderate; Grade 3: severe or medically significant; Grade 4: life-threatening consequences. Higher grade indicates greater severity and an increase in CTCAE grade was defined relative to the Baseline grade. Baseline was defined as the most recent, non-missing value prior to or on the first study treatment dose date. Any worst-case post baseline increase in grade along with any increase to a maximum grade of 3 and a maximum grade of 4 are presented.

Blood samples were collected for the analysis of following hematology parameters: basophils, eosinophils, mean corpuscular hemoglobin concentration (MCHC), mean corpuscular hemoglobin (MCH), mean corpuscular volume (MCV), erythrocytes, hematocrit, monocytes, neutrophils and reticulocyte. The summaries of worst-case change from baseline with respect to normal range was analyzed for only those laboratory tests that were not gradable by CTCAE version 4.03. The number of participants with decreases to low from baseline, changes to normal or no changes from baseline, and increases to high values have been presented.

Blood samples were collected for the analysis of clinical chemistry parameters: glucose, alanine aminotransferase (ALT), albumin, alkaline phosphatase, aspartate aminotransferase (AST), blood bilirubin, calcium, creatine kinase (CPK), creatinine, gamma glutamyl transferase (GGT), magnesium, phosphate, potassium and sodium. Laboratory parameters were graded according to NCI-CTCAE version 4.03. Grade 1: mild; Grade 2: moderate; Grade 3: severe or medically significant; Grade 4: life-threatening consequences. Higher grade indicates greater severity and an increase in CTCAE grade was defined relative to the Baseline grade. Baseline was defined as the most recent, non-missing value prior to or on the first study treatment dose date. Any worst case post baseline increase in grade along with any increase to a maximum grade of 3 and a maximum grade of 4 are presented.

Blood samples were collected for the analysis of following chemistry parameters: calcium, carbon dioxide, chloride, direct bilirubin, protein, thyrotropin (TSH), thyroxine (T4) and triiodothyronine (T3). The summaries of worst case change from baseline with respect to normal range was analyzed for only those laboratory tests that were not gradable by CTCAE version 4.03. The number of participants with decreases to low from baseline, changes to normal or no changes from baseline, and increases to high values have been presented.

Urine samples were collected to assess urine glucose, protein, occult blood and ketones using dipstick method. The dipstick test gave results in a semi-quantitative manner, and results for urinalysis parameters were recorded as negative, trace, 1+, 2+, 3+ indicating proportional concentrations in the urine sample. Baseline was defined as the most recent, non-missing value prior to or on the first study treatment dose date. Result for urinalysis parameters were recorded as no change/decreased and any increase. Data for worst-case post baseline urinalysis results is presented.

Urine samples were collected from participants to assess urine pH levels. Baseline was defined as the most recent, non-missing value prior to or on the first study treatment dose date.

Urine samples were collected from participants to assess urine specific gravity. Baseline was defined as the most recent, non-missing value prior to or on the first study treatment dose date.

DBP and SBP were measured after resting for at least 5 minutes in a supine or semi-recumbent position. They were graded according to NCI-CTCAE version 4.03. For SBP: Grade 0 (\<=120 millimeter of mercury \[mmHg\]), Grade 1 (121-139 mmHg), Grade 2 (140-159 mmHg), Grade 3 (\>=160 mmHg). For DBP: Grade 0 (\<=80 mmHg), Grade 1 (81-89 mmHg), Grade 2 (90-99 mmHg), Grade 3 (\>=100 mmHg). Higher grade indicates greater severity. Baseline was defined as the most recent, non-missing value prior to or on the first study treatment dose date. Data for worst-case post baseline with any grade increase and a maximum post-baseline grade increase to Grade 3 from their baseline grade are presented.

Vital signs (pulse rate and temperature) were measured after resting for at least 5 minutes in a supine or semi-recumbent position. The abnormal vital sign ranges were: For pulse rate (low \<60 beats per minute \[bpm\] and high \>100 bpm); For body temperature (\<=35 degrees Celsius or \>=38 degrees Celsius). Baseline was defined as the most recent, non-missing value prior to or on the first study treatment dose date. Data for worst case change from baseline was presented as Baseline to low, Baseline to Normal or No change and Baseline to High.

ORR was defined as the percentage of participants with a confirmed partial response (PR) or better (i.e., PR, very good partial response \[VGPR\], complete response \[CR\] and stringent complete response \[sCR\]), according to the International Myeloma Working Group (IMWG) Response Criteria. CR = negative immunofixation of serum and urine AND disappearance of any soft tissue plasmacytomas AND \<5% plasmacytomas in the bone marrow; sCR=stringent complete response, CR as above PLUS normal serum free light-chain (FLC) assay ratio and absence of clonal cells in bone marrow by immunohistochemistry or immunofluorescence; VGPR = serum and urine M-component detectable by immunofixation but not on electrophoresis OR ≥ 90% reduction in serum M-component plus urine M-component \<100 mg/24 h; PR = ≥50% reduction of serum M-protein and reduction in 24-hour urinary M-protein by ≥90% or to \<200 mg/24 h.

DLT is an Adverse Event (AE) that is considered by the investigator to be clinically relevant and attributed to the study therapy during the 21-day DLT period and meets at least one of the DLT criteria: Grade 3 or greater febrile neutropenia lasting \>48 hours (h) despite adequate treatment, Grade 4 thrombocytopenia \<25,000/mm\^3accompanied by clinically significant bleeding, any Grade 3 or greater non-hematologic toxicity, any Grade 3 or greater non-hematologic laboratory value if: laboratory abnormality persists for \>48 h despite supportive treatment for abnormality leads to hospitalization, Grade 4 Corneal toxicity, and liver toxicity meeting pre-specified GlaxoSmithKline liver stopping criteria. DLTs were assessed by National Cancer Institute- Common Toxicity Criteria for Adverse Events (NCI-CTCAE), version 4.03.

DLT is an AE that is considered by the investigator to be clinically relevant and attributed to the study therapy during the 21-day DLT period and meets at least one of the DLT criteria: Grade 3 or greater febrile neutropenia lasting \>48 hours (h) despite adequate treatment, Grade 4 thrombocytopenia \<25,000/mm\^3 accompanied by clinically significant bleeding, any Grade 3 or greater non-hematologic toxicity, any Grade 3 or greater non-hematologic laboratory value if: laboratory abnormality persists for \>48 h despite supportive treatment or abnormality leads to hospitalization, Grade 4 Corneal toxicity, and liver toxicity meeting pre-specified GlaxoSmithKline liver stopping criteria. DLTs were assessed by NCI-CTCAE, version 4.03.

DLT is an AE that is considered by the investigator to be clinically relevant and attributed to the study therapy during the 21-day DLT period and meets at least one of the DLT criteria: Grade 3 or greater febrile neutropenia lasting \>48 hours (h) despite adequate treatment, Grade 4 thrombocytopenia \<25,000/mm\^3 accompanied by clinically significant bleeding, any Grade 3 or greater non-hematologic toxicity, any Grade 3 or greater non-hematologic laboratory value if: laboratory abnormality persists for \>48 h despite supportive treatment or abnormality leads to hospitalization, Grade 4 Corneal toxicity, and liver toxicity meeting pre-specified GlaxoSmithKline liver stopping criteria. DLTs were assessed by NCI-CTCAE, version 4.03.

An AE is defined as any untoward medical occurrence in a participant or clinical investigation participant, temporally associated with the use of a medicinal product, whether or not considered related to the medicinal product. An SAE is defined as any untoward medical occurrence that, at any dose, results in death; was life threatening; required hospitalization or prolongation of existing hospitalization; resulted in disability/incapacity; was a congenital anomaly/birth defect. SAEs are subset of AEs.

An AE is any untoward medical occurrence in a clinical study participant, temporally associated with the use of a study treatment, whether or not considered related to the study treatment. SAE is defined as any untoward medical occurrence that, at any dose results in death, Is life-threatening, Requires inpatient hospitalization or prolongation of existing hospitalization, Results in persistent disability/incapacity or Is a congenital anomaly/birth defect other situations which involve medical or scientific judgment or is associated with liver injury and impaired liver function. SAEs are subset of AEs.

Blood samples were collected for clinical chemistry parameters analysis: Creatine Kinase (CK), Creatinine, Gamma Glutamyl Transferase (GGT), Magnesium, Phosphate, Potassium, Sodium, Calcium, Glucose, Urate, Alanine Aminotransferase (ALT), Albumin, Alkaline Phosphatase (ALP), Aspartate Aminotransferase (AST), Bilirubin were graded according to National Cancer Institute-Common Terminology Criteria for Adverse Events (NCI-CTCAE) version (v) 4.03. Grade (G)1: mild; G2: moderate; G3: severe or medically significant; G4: life-threatening consequences. Higher grade indicates greater severity and increase in grade was defined relative to Baseline grade. Any worst-case post baseline increases in grade along with any increase to a maximum G3 and a maximum G4 are presented. Baseline was defined as the latest pre-dose assessment within 21 days prior to first dose with a non-missing value, including those from unscheduled visits.

Blood samples were collected for analysis of clinical chemistry parameters: C Reactive Protein, Chloride, Direct Bilirubin (DB), Lactate Dehydrogenase, Protein and Urea. The summaries of worst-case change from baseline with respect to normal range was analyzed for only those laboratory tests that were not gradable by CTCAE v4.03. The number of participants with decreases to low from baseline, changes to normal or no changes from baseline, and increases to high values have been presented. Baseline was defined as the latest pre-dose assessment within 21 days prior to first dose with a non-missing value, including those from unscheduled visits.

Blood samples were collected for clinical chemistry parameters analysis: Creatine Kinase (CK), Creatinine, Gamma Glutamyl Transferase (GGT), Magnesium, Phosphate, Potassium, Sodium, Calcium, Glucose, Urate, Alanine Aminotransferase (ALT), Albumin, Alkaline Phosphatase (ALP), Aspartate Aminotransferase (AST), Bilirubin were graded according to NCI-CTCAE v 4.03. G1: mild; G2: moderate; G3: severe or medically significant; G4: life-threatening consequences. Higher grade indicates greater severity and increase in grade was defined relative to Baseline grade. Any worst-case post baseline increases in grade along with any increase to a maximum G3 and a maximum G4 are presented. Baseline was defined as the latest pre-dose assessment within 21 days prior to first dose with a non-missing value, including those from unscheduled visits.

Blood samples were collected for analysis of clinical chemistry parameters: C Reactive Protein, Chloride, Direct Bilirubin (DB), Lactate Dehydrogenase, Protein and Urea. The summaries of worst-case change from baseline with respect to normal range was analyzed for only those laboratory tests that were not gradable by CTCAE v4.03. The number of participants with decreases to low from baseline, changes to normal or no changes from baseline, and increases to high values have been presented. Baseline was defined as the latest pre-dose assessment within 21 days prior to first dose with a non-missing value, including those from unscheduled visits.

Blood samples were collected for analysis of hematology parameters: Hemoglobin, Leukocytes, Lymphocytes, Neutrophils and Platelets were graded according to CTCAE v4.03. G1: mild; G2: moderate; G3: severe or medically significant; G4: life-threatening consequences. Higher grade indicates greater severity and increase in grade was defined relative to Baseline grade. Any worst-case post baseline increases in grade along with any increase to a maximum G3 and a maximum G4 are presented. Baseline was defined as the latest pre-dose assessment within 21 days prior to first dose with a non-missing value, including those from unscheduled visits.

Blood samples were collected for the analysis of following hematology parameters: Basophils, Eosinophils, Mean Corpuscular Hemoglobin Concentration (MCHC), Mean Corpuscular Hemoglobin (MCH), Mean Corpuscular Volume (MCV), erythrocytes, Hematocrit, monocytes and reticulocytes. The summaries of worst-case change from baseline with respect to normal range was analyzed for only those laboratory tests that were not gradable by CTCAE version 4.03. The number of participants with decreases to low from baseline, changes to normal or no changes from baseline, and increases to high values have been presented. Baseline was defined as the latest pre-dose assessment within 21 days prior to first dose with a non-missing value, including those from unscheduled visits.

Blood samples were collected for analysis of hematology parameters: Hemoglobin, Leukocytes, Lymphocytes, Neutrophils and Platelets were graded according to CTCAE v4.03. G1: mild; G2: moderate; G3: severe or medically significant; G4: life-threatening consequences. Higher grade indicates greater severity and increase in grade was defined relative to Baseline grade. Any worst-case post baseline increases in grade along with any increase to a maximum G3 and a maximum G4 are presented. Baseline was defined as the latest pre-dose assessment within 21 days prior to first dose with a non-missing value, including those from unscheduled visits.

Blood samples were collected for the analysis of following hematology parameters: Basophils, Eosinophils, MCHC, MCH, MCV, erythrocytes, Hematocrit, monocytes and reticulocytes. The summaries of worst-case change from baseline with respect to normal range was analyzed for only those laboratory tests that were not gradable by CTCAE version 4.03. The number of participants with decreases to low, changes to normal or no changes, and increases to high from baseline values have been presented. Baseline was defined as the latest pre-dose assessment within 21 days prior to first dose with a non-missing value, including those from unscheduled visits.

Urine samples were collected to analyze presence of occult blood and protein in urine by dipstick method. Data for worst-case post baseline urinalysis results is presented. Result for urinalysis parameters were recorded as no change/decreased, Increase to SMALL, Increase to MODERATE, Increase to LARGE, and any increase including increase to +-, 1+, 2+, 3+, unknown indicating proportional concentrations in the urine sample.

Urine samples were collected to analyze presence of occult blood and protein in urine by dipstick method. Data for worst-case post baseline urinalysis results is presented. Result for urinalysis parameters were recorded as no change/decreased, Increase to SMALL, Increase to MODERATE, Increase to LARGE, and any increase including increase to +-, 1+, 2+, 3+, unknown indicating proportional concentrations in the urine sample.

Urine samples were collected to analyze urine pH levels. Baseline was defined as the latest pre-dose assessment within 21 days prior to first dose with a non-missing value, including those from unscheduled visits.

Urine samples were collected to analyze urine pH levels. Baseline was defined as the latest pre-dose assessment within 21 days prior to first dose with a non-missing value, including those from unscheduled visits.

Urine samples were collected to analyze urine specific gravity. Baseline was defined as the latest pre-dose assessment within 21 days prior to first dose with a non-missing value, including those from unscheduled visits.

Urine samples were collected to analyze urine specific gravity. Baseline was defined as the latest pre-dose assessment within 21 days prior to first dose with a non-missing value, including those from unscheduled visits.

DBP and SBP were measured after resting for at least 5 minutes in a supine or semi-recumbent position. They were graded according to NCI-CTCAE version 4.03. For SBP: Grade (G) 0 (\<120 millimeter of mercury \[mmHg\]), G1 (120-139 mmHg), G2 (140-159 mmHg), G3 (\>=160 mmHg). For DBP: G0 (\<80 mmHg), G1 (80-89 mmHg), G2 (90-99 mmHg), G3 (\>=100 mmHg). Higher grade indicates greater severity. Data for participants with worst-case post baseline with any grade increase and a maximum post-baseline grade increase to G2 and G3 from their baseline grade are presented. Baseline was defined as the latest pre-dose assessment within 21 days prior to first dose with a non-missing value, including those from unscheduled visits.

DBP and SBP were measured after resting for at least 5 minutes in a supine or semi-recumbent position. They were graded according to NCI-CTCAE version 4.03. For SBP: Grade (G) 0 (\<120 millimeter of mercury \[mmHg\]), G1 (120-139 mmHg), G2 (140-159 mmHg), G3 (\>=160 mmHg). For DBP: G0 (\<80 mmHg), G1 (80-89 mmHg), G2 (90-99 mmHg), G3 (\>=100 mmHg). Higher grade indicates greater severity. Data for participants with worst-case post baseline with any grade increase and a maximum post-baseline grade increase to G2 and G3 from their baseline grade are presented. Baseline was defined as the latest pre-dose assessment within 21 days prior to first dose with a non-missing value, including those from unscheduled visits.

Temperature was measured after resting for at least 5 minutes. The abnormal ranges for body temperature were (\<=35 degrees Celsius or \>=38 degrees Celsius). Baseline was defined as the latest pre-dose assessment within 21 days prior to first dose with a non-missing value, including those from unscheduled visits.

Temperature was measured after resting for at least 5 minutes. The abnormal ranges for body temperature were (\<=35 degrees Celsius or \>=38 degrees Celsius). Baseline was defined as the latest pre-dose assessment within 21 days prior to first dose with a non-missing value, including those from unscheduled visits.

Heart rate was measured after resting for at least 5 minutes. The abnormal ranges for heart rate were (low \<60 beats per minute \[bpm\] and high \>100 bpm). Baseline was defined as the latest pre-dose assessment within 21 days prior to first dose with a non-missing value, including those from unscheduled visits. Data for participants with worst case change from baseline was presented as Baseline to low, Baseline to Normal or No change and Baseline to High.

Heart rate was measured after resting for at least 5 minutes. The abnormal ranges for heart rate were (low \<60 beats per minute \[bpm\] and high \>100 bpm). Baseline was defined as the latest pre-dose assessment within 21 days prior to first dose with a non-missing value, including those from unscheduled visits. Data for participants with worst case change from baseline was presented as Baseline to low, Baseline to Normal or No change and Baseline to High.

12-lead electrocardiogram (ECG) was obtained using an automated ECG machine that automatically calculated the heart rate and measured PR, QRS, QT, and QT interval corrected using Fridericia's formula (QTcF) intervals. Grade 0 (\<450 millisecond (msec)), Grade 1 (450-480 msec), Grade 2 (481-500 msec), and Grade 3 (≥501 msec). Higher grade indicates greater severity. Data for participants with worst-case post baseline with any grade increase and a post-baseline grade increase to G2 and G3 from their baseline grade are presented. Baseline was defined as the latest pre-dose assessment within 21 days prior to first dose with a non-missing value, including those from unscheduled visits.

12-lead electrocardiogram (ECG) was obtained using an automated ECG machine that automatically calculated the heart rate and measured PR, QRS, QT, and QT interval corrected using Fridericia's formula (QTcF) intervals. Grade 0 (\<450 millisecond (msec)), Grade 1 (450-480 msec), Grade 2 (481-500 msec), and Grade 3 (≥501 msec). Higher grade indicates greater severity. Data for participants with worst-case post baseline with any grade increase and a post-baseline grade increase to G2 and G3 from their baseline grade are presented. Baseline was defined as the latest pre-dose assessment within 21 days prior to first dose with a non-missing value, including those from unscheduled visits.

The number of participants with worst-case post baseline performance status have been presented as 0-5. Where, 0- Fully active; 1- Restricted in strenuous activity but able to carry out light work activities; 2- Capable of self-care but unable to carry out any work activities; 3- Capable of limited self care, confined to bed/chair more than 50% of waking hours; 4- Completely disabled; can't carry on any self care; totally confined to bed/chair and 5- Dead.Baseline was defined as the latest pre-dose assessment within 21 days prior to first dose with a non-missing value, including those from unscheduled visits.

Any change in ECOG Performance status that was clinically significant in the medical and scientific judgment of the investigator and not related to an underlying disease was reported.

DLT is an adverse event (AE) that is considered by the investigator to be clinically relevant and attributed to the study therapy during the 28 day DLT period and meets at least one of the DLT criteria: Grade 3 or greater febrile neutropenia lasting \>48 hours (h) despite adequate treatment; Grade 4 thrombocytopenia \<25,000/mm\^3 accompanied by significant bleeding; any Grade 3 or greater non-hematologic laboratory value (if laboratory abnormality persist \>48 h despite supportive treatment or abnormality leading to hospitalisation); non-hematologic toxicity which does not resolve with appropriate supportive treatment within 48 h, Grade 4 corneal adverse events; and other organ specific toxicities (liver toxicity that causes discontinuation of treatment).

DLT is an adverse event (AE) that is considered by the investigator to be clinically relevant and attributed to the study therapy during the 21 day DLT period and meets at least one of the DLT criteria: Grade 3 or greater febrile neutropenia lasting \>48 hours (h) despite adequate treatment; Grade 4 thrombocytopenia \<25,000/mm\^3 accompanied by significant bleeding; any Grade 3 or greater non-hematologic laboratory value (if laboratory abnormality persist \>48 h despite supportive treatment or abnormality leading to hospitalisation); non-hematologic toxicity which does not resolve with appropriate supportive treatment within 48 h, Grade 4 corneal adverse events; and other organ specific toxicities (liver toxicity that causes discontinuation of treatment).

12-lead electrocardiogram (ECGs) were obtained using an automated ECG machine that automatically calculated the QTcF intervals. QTc values are categorized into the clinical concern ranges which are specific to changes in QTc: 31-60 milliseconds (msec), and \>60 msec, and \>530msec. An increase is defined relative to Baseline. Baseline (Day 1) was defined as latest pre-dose assessment with non-missing value, including unscheduled visits. Data of number of participants with worst-case increase post baseline is presented.

Blood samples were collected for analysis of following hematology parameters: Hemoglobin (hemoglobin increased and anemia), Lymphocytes (lymphocyte count increased and lymphocyte count decreased), Neutrophils, Platelets and Leukocytes (leukocytosis and white blood cells decreased). The laboratory parameters were graded according to Common Terminology Criteria for Adverse Events (CTCAE) version (v) 4.03. Grade (G) 1: mild; G2: moderate; G3: severe or medically significant; G4: life-threatening consequences. Higher grade indicates greater severity and increase in grade was defined relative to Baseline grade. Baseline (Day 1) was defined as latest pre-dose assessment with non-missing value, including unscheduled visits. Any worst-case post baseline increases in grade along with any increase to a maximum G3 and a maximum G4 are presented.

Blood samples were collected for the analysis of following hematology parameters: basophils, eosinophils, hematocrit, mean corpuscular hemoglobin concentration (MCHC), mean corpuscular hemoglobin (MCH), mean corpuscular volume (MCV), monocytes, erythrocytes and reticulocyte. The summaries of worst-case change from baseline with respect to normal range was analyzed for only those laboratory tests that were not gradable by CTCAE version 4.03. The number of participants with decreases to low from baseline, changes to normal or no changes from baseline, and increases to high values from baseline have been presented. Baseline (Day 1) was defined as latest pre-dose assessment with non-missing value, including unscheduled visits.

Blood samples were collected for analysis of following clinical chemistry parameters: Hyperglycemia, Hypoglycemia, Albumin, Alkaline Phosphatase, Alanine Aminotransferase (ALT), Aspartate Aminotransferase, (AST), Bilirubin, Creatine Kinase (CK), Creatinine, Gamma Glutamyl Transferase (GGT), Hyperkalemia, Hypokalemia, Hypermagnesemia, Hypomagnesemia, Phosphate, Hypernatremia, Hyponatremia, Urate, Hypercalcemia and Hypocalcemia. Laboratory parameters were graded according to CTCAE v4.03. Grade (G) 1: mild; G2: moderate; G3: severe or medically significant; G4: life-threatening consequences. Higher grade indicates greater severity and increase in grade was defined relative to Baseline grade. Baseline (Day 1) was defined as latest pre-dose assessment with non-missing value, including unscheduled visits. Any worst-case post baseline increases in grade along with any increase to a maximum G3 and a maximum G4 are presented.

Blood samples were collected for analysis of following clinical chemistry parameters: Direct Bilirubin (DB), Calcium, Chloride, Carbon Dioxide (CO2), lactate dehydrogenase (LDH) and Protein. The summaries of worst-case change from baseline with respect to normal range was analyzed for only those laboratory tests that were not gradable by CTCAE version 4.03. The number of participants with decreases to low from baseline, changes to normal or no changes from baseline, and increases to high values from baseline have been presented. Baseline (Day 1) was defined as latest pre-dose assessment with non-missing value, including unscheduled visits.

Urine samples were collected to analyze presence of occult blood and protein in urine by dipstick method. Data for worst-case post baseline urinalysis results is presented. Result for urinalysis parameters were recorded as no change/decreased and increase to trace, 1+, 2+, 3+, \>3+ indicating proportional concentrations in the urine sample. Baseline (Day 1) was defined as latest pre-dose assessment with non-missing value, including unscheduled visits.

Urine samples were collected to analyze urine pH levels. Baseline (Day 1) was defined as latest pre-dose assessment with non-missing value, including unscheduled visits.

Urine samples were collected to analyze urine specific gravity using dipstick method. Baseline (Day 1) was defined as latest pre-dose assessment with a non-missing value, including unscheduled visits.

Blood pressures (DBP and SBP) were measured after resting for at least 5 minutes in a supine or semi-recumbent position. Baseline (Day 1) was defined as latest pre-dose assessment with a non-missing value, including unscheduled visits. Change from Baseline was calculated as post-dose visit value minus Baseline value.

Pulse rate was measured after resting for at least 5 minutes in a supine or semi-recumbent position. Baseline (Day 1) was defined as latest pre-dose assessment with a non-missing value, including unscheduled visits. Change from Baseline was calculated as post-dose visit value minus Baseline value.

Temperature was measured after resting for at least 5 minutes in a supine or semi-recumbent position. Baseline (Day 1) was defined as latest pre-dose assessment with a non-missing value, including unscheduled visits. Change from Baseline was calculated as post-dose visit value minus Baseline value.

ORR was defined as the percentage of participants with a confirmed partial response (PR) or better (i.e., PR, very good partial response \[VGPR\], complete response \[CR\] and stringent complete response \[sCR\]), according to the International Myeloma Working Group (IMWG) Response Criteria. CR: negative immunofixation of serum and urine and disappearance of any soft tissue plasmacytomas and \<5% plasmacytomas in the bone marrow; sCR: stringent complete response, CR as above plus normal serum free light-chain (FLC) assay ratio and absence of clonal cells in bone marrow by immunohistochemistry or immunofluorescence; VGPR: serum and urine M-component detectable by immunofixation but not on electrophoresis OR \>= 90% reduction in serum M-component plus urine M-component \<100 mg/24 h; PR: \>=50% reduction of serum M-protein and reduction in 24-hour urinary M-protein by \>=90% or to \<200 mg/24 h. Confidence intervals were based on the exact method.