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Sub-study of Belantamab Mafodotin (GSK2857916) as Monotherapy and in Combination With Dostarlimab (GSK4057190) in Participants With RRMM

A Phase I/II, Randomized, Open-label Platform Study Utilizing a Master Protocol to Study Belantamab Mafodotin (GSK2857916) as Monotherapy and in Combination With Anti-Cancer Treatments in Participants With Relapsed/Refractory Multiple Myeloma (RRMM)-DREAMM5. Sub-study 4 - Belantamab Mafodotin and Dostarlimab (GSK4057190) in Combination

Status
Terminated
Phases
Phase 1Phase 2
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT06655818
Enrollment
4
Registered
2024-10-23
Start date
2021-03-09
Completion date
2024-02-14
Last updated
2025-03-03

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Relapsed/Refractory Multiple Myeloma

Brief summary

The primary purpose is to determine the safety and tolerability of belantamab mafodotin in combination with other anti-cancer treatments (in each sub-study), and to establish the recommended Phase 2 dose for each combination treatment to explore in the cohort expansion phase. This study is a sub study of the Master protocol (NCT04126200).

Interventions

DRUGBelantamab Mafodotin

Belantamab Mafodotin will be administered.

DRUGDostarlimab

Dostarlimab will be administered.

Sponsors

GlaxoSmithKline
Lead SponsorINDUSTRY

Study design

Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No

Inclusion criteria

* Participant must be 18 years of age inclusive or older, at the time of signing the informed consent. * Participants must have histologically or cytologically confirmed diagnosis of Multiple Myeloma (MM), as defined by the IMWG. * Participants having at least 3 prior lines of prior anti-myeloma treatments including an immunomodulating agent (IMID) a proteasome inhibitor (PI) and an anti-CD38 monoclonal antibody. * Participants with a history of autologous stem cell transplant are eligible for study participation when, transplant was \>100 days prior to study enrolment and with no active infection(s). * Participants with Eastern Cooperative Oncology Group (ECOG) performance status of 0-1, unless ECOG less than equal to (\<=)2 is due solely to skeletal complications and/or skeletal pain due to MM. * Participants with measurable disease defined as at least one of the following: Serum M-protein greater than equal to (\>=)0.5 gram per deciliter (\>=5 gram per liter) or Urine M-protein \>=200 milligrams (mg) per 24 hours or Serum free light chain (FLC) assay: Involved FLC level \>=10 mg per deciliter (\>=100 mg per Liter) and an abnormal serum FLC ratio (\<0.26 or \>1.65). * Participants who have tested positive for Hepatitis B core antibody (HBcAb) can be enrolled if the following criteria are met: Serology result HBcAb+, Hepatitis B surface antigen (HBsAg)-; HBV deoxyribonucleic acid (DNA) undetectable during screening. * Participants who are currently receiving physiological doses oral steroids (\<10 mg/day), inhaled steroids or ophthalmological steroids.

Exclusion criteria

* Participants with current corneal epithelial disease except mild punctate keratopathy. * Participants with evidence of cardiovascular risk. * Participants with known immediate or delayed hypersensitivity reaction or idiosyncrasy to drugs chemically related to belantamab mafodotin or any of the components of the study treatment. History of severe hypersensitivity to other mAb. * Participants with active infection requiring antibiotic, antiviral, or antifungal treatment. * Participants with other monoclonal antibodies within 30 days or systemic anti-myeloma therapy within \<14 days. * Participants with prior radiotherapy within 2 weeks of start of study therapy. * Participants with prior allogeneic transplant are prohibited. * Participants who have received prior Chimeric Antigen T cell therapy (CAR-T) therapy with lymphodepletion with chemotherapy within 3 months of screening. * Participants with any major surgery (other than bone-stabilizing surgery) within the last 30 days. * Participants with prior treatment with an investigational agent within 14 days or 5 half-lives of receiving the first dose of study drugs, whichever is shorter. * Participants with \>=grade 3 toxicity considered related to prior check-point inhibitors and that led to treatment discontinuation. * Participants who have received transfusion of blood products within 2 weeks before the first dose of study drug. * Participants must not receive live attenuated vaccines within 30 days prior to first dose of study treatment or whilst receiving belantamab mafodotin +- partner agent in any sub-study arm of the platform trial and for at least 70 days following last study treatment. * Participants with presence of active renal condition (infection, requirement for dialysis or any other condition that could affect participant's safety). Participants with isolated proteinuria resulting from MM. * Participants with known human immunodeficiency virus (HIV) infection, unless the participant can meet all criteria: a) established anti-retroviral therapy for at least 4 weeks and HIV viral load\<400 copies/milliliter (mL) b) cluster of differentiation 4 plus (CD4+) T-cell (CD4+) counts \>= 350 cells/microliter (µL) c) No history of Acquired immunodeficiency syndrome (AIDS)-defining opportunistic infections within the last 12 months in which case the participant would be eligible for CE Phase only. * Participants with autoimmune disease (current or history) or syndrome that required systemic treatment within the past 2 years. * Exclusion for a recent (within the past 6 months) history of symptomatic pericarditis. * Participant has an active autoimmune disease that has required systemic treatment in the past 2 years (i.e. with use of disease-modifying agents, corticosteroids, or immunosuppressive drugs). * Participants who have received prior therapy with an anti-programmed death-1 (anti-PD-1), anti-PD-1-ligand-1 (anti-PD-L1), or anti-PD-1 ligand-2 (anti-PD-L2) agent. * Participant has a diagnosis of immunodeficiency or is receiving systemic steroid therapy or any other form of immunosuppressive therapy within 7 days prior to the first dose of study treatment. Use of inhaled steroids, local injection of steroids, and steroid eye drops are allowed.

Design outcomes

Primary

MeasureTime frameDescription
DE Phase: Number of Participants With Dose Limiting Toxicities (DLT)Up to 21 daysCriteria 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 DLTs. Severity was graded using National Cancer Institute - Common Terminology Criteria for Adverse Events (version 5.0).
DE Phase: Number of Participants With Adverse Events (AEs)Up to 153 weeksAn 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.
DE Phase: Number of Participants With Worst-Case Hematology Results by Maximum Grade Increase Post - Baseline Relative to BaselineBaseline (Day 1) and up to 153 weeksBlood samples were collected for the analysis of following hematology parameters: eosinophils, anemia, hemoglobin increased, lymphocyte count decreased, lymphocyte count increased, neutrophil count decreased, platelet count decreased, leukocytosis and white blood cell decreased. 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. The laboratory parameters were graded according to Common Terminology Criteria for Adverse Events (CTCAE) version 5.
DE Phase: Number of Participants With Worst-Case Chemistry Results by Maximum Grade Increase Post - Baseline Relative to BaselineBaseline (Day 1) and up to 153 weeksBlood samples were collected for the analysis of following chemistry parameters: Hypoglycemia, hypoalbuminemia, alkaline phosphatase (ALP) increased, alanine aminotransferase (ALT) increased, aspartate aminotransferase (AST) increased, blood bilirubin increased, creatine kinase (CPK) increased, creatinine increased, gamma glutamyl transferase (GGT) increased, hyperkalemia, blood lactate dehydrogenase (LDH) increased, hypermagnesemia, hypomagnesemia, hypernatremia, hypercalcemia, hypocalcemia and chronic kidney disease. G1: mild; G2: moderate; G3: severe. 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 and G3 are presented. The laboratory parameters were graded according to CTCAE version 5.
CE Phase: Overall Response Rate (ORR)Up to 26 weeksOverall Response Rate (ORR) was defined as the percentage of participants with a confirmed PR or better as the best overall response (i.e., Partial Response \[PR\], 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). CR defined as negative immunofixation of serum and urine AND disappearance of any soft tissue plasmacytomas AND \<5% plasmacytomas in the bone marrow; sCR 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; VGPR 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; PR defined as ≥50% reduction of serum M-protein and reduction in 24-hour urinary M-protein by ≥90% or to \<200 mg/24 h.

Secondary

MeasureTime frameDescription
DE Phase: Belantamab Mafodotin Concentrations for Plasma Total AntibodyPredose, end of infusion (EOI), 2, and 24 hours postdose on Cycle 1 Day 1, and at Cycle 1 Day 4, Day 8, Day 22, Predose and EOI on Cycle 2 Day 1, Cycle 4 Day 1, and at end of treatment (approximately 153 weeks)Blood samples were collected for PK analysis of belantamab mafodotin total antibody when administered intravenously in combination with dostarlimab.
DE Phase: Belantamab Mafodotin Concentrations for Plasma Cys-mcMMAFPredose, end of infusion (EOI), 2, and 24 hours postdose on Cycle 1 Day 1, and at Cycle 1 Day 4, Day 8, Day 22, Predose and EOI on Cycle 2 Day 1, Cycle 4 Day 1, and at end of treatment (approximately 153 weeks)Blood samples were collected for PK analysis of belantamab mafodotin cys-mcMMAF when administered intravenously in combination with dostarlimab.
CE Phase: Plasma Concentrations of Belantamab Mafodotin Antibody-Drug Conjugate (ADC)Up to 153 weeksBlood samples were to be collected for PK analysis of Belantamab Mafodotin Antibody-Drug Conjugate (ADC).
CE Phase: Plasma Concentration of Belantamab Mafodotin Plasma Total AntibodyUp to 153 weeksBlood samples were to be collected for PK analysis of Belantamab mafodotin plasma total antibody.
CE Phase: Plasma Concentrations of Belantamab Mafodotin Cys- Monomethyl Auristatin-F (Cys-mcMMAF)Up to 153 weeksBlood samples were to be collected for PK analysis of Belantamab Mafodotin Cys- Monomethyl Auristatin-F (Cys-mcMMAF)
DE Phase: Dostarlimab Concentration When Administered in Combination With Belantamab MafodotinPredose and end of infusion (EOI) on Cycle 1 Day 1, Cycle 2 Day 1, Cycle 5 Day 1, and at the end of treatment (approximately 153 weeks)Blood samples were collected for PK analysis of dostarlimab when administered intravenously in combination with belantamab mafodotin.
CE Phase: Dostarlimab Concentration When Administered in Combination With Belantamab MafodotinUp to 153 weeksBlood samples were to be collected for PK analysis of dostarlimab when administered intravenously in combination with belantamab mafodotin.
DE Phase: Number of Participants With Post-baseline Positive Anti-drug Antibodies (ADAs) Against Belantamab MafodotinUp to 153 weeksSerum samples were collected for the analysis of the presence of ADAs using validated immunoassays. All samples were tested in screening assay, and positive samples were further characterized for antibody titers.
CE Phase: Number of Participants With Post-baseline Positive ADAs Against Belantamab MafodotinUp to 153 weeksSerum samples were to be collected for the analysis of the presence of ADAs using validated immunoassays. All samples were to be further tested in screening assay, and positive samples were further to be characterized for antibody titers.
DE Phase: Number of Participants With Post-baseline Positive ADAs Against DostarlimabUp to 153 weeksSerum samples were collected for the analysis of the presence of ADAs using validated immunoassays. All samples were tested in screening assay, and positive samples were further characterized for antibody titers.
CE Phase: Number of Participants With Post-baseline Positive ADAs Against DostarlimabUp to 153 weeksSerum samples were to be collected for the analysis of the presence of ADAs using validated immunoassays. All samples were to be further tested in screening assay, and positive samples were further to be characterized for antibody titers.
DE Phase: Concentration of ADAs Against Dostarlimab When Administered in Combination With Belantamab MafodotinUp to 153 weeksSerum samples were collected for the analysis of the presence of ADAs using validated immunoassays. All samples were to be further tested in screening assay, and positive samples were further to be characterized for antibody titers.
CE Phase: Concentration of ADAs Against Dostarlimab When Administered in Combination With Belantamab MafodotinUp to 153 weeksSerum samples were to be collected for the analysis of the presence of ADAs using validated immunoassays. All samples were to be further tested in screening assay, and positive samples were further to be characterized for antibody titers.
DE Phase: Concentration of ADAs Against Belantamab MafodotinUp to 153 weeksSerum samples were collected for the analysis of the presence of ADAs using validated immunoassays. All samples were to be further tested in screening assay, and positive samples were further to be characterized for antibody titers.
DE Phase: Overall Response Rate (ORR)Up to 153 weeksOverall Response Rate (ORR) was defined as the percentage of participants with a confirmed PR or better as the best overall response (i.e., Partial Response \[PR\], 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). CR defined as negative immunofixation of serum and urine AND disappearance of any soft tissue plasmacytomas AND \<5% plasmacytomas in the bone marrow; sCR 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; VGPR 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; PR defined as ≥50% reduction of serum M-protein and reduction in 24-hour urinary M-protein by ≥90% or to \<200 mg/24 h.
DE Phase: Number of Participants With Adverse Events of Special Interest (AESI)Up to 153 weeksAn adverse event (AE) is any untoward medical occurrence in a clinical study participant, temporally associated with the use of a medicinal product, whether or not considered related to the medicinal product. Adverse events of special interest (AESIs) were collected.
CE Phase: Number of Participants With Adverse Events of Special Interest (AESI)Up to 153 weeksAn adverse event (AE) is any untoward medical occurrence in a clinical study participant, temporally associated with the use of a medicinal product, whether or not considered related to the medicinal product. Adverse events of special interest (AESIs) were to be collected.
DE Phase: Number of Participants With Any Corneal Event by Maximum Grade as Per CTCAE GradeUp to 153 weeksThe corneal events were graded according to CTCAE version 5. Grade 1: mild; Grade 2: moderate; Grade 3: severe or medically significant. Higher grade indicates greater severity and an increase in CTCAE grade was defined relative to the Baseline grade. Results are presented for number of participants with any corneal events by maximum grade as per CTCAE grade.
CE Phase: Number of Participants With Any Corneal Events by Maximum Grade as Per CTCAE GradeUp to 153 weeksThe corneal events were to be graded according to CTCAE version 5. Grade 1: mild; Grade 2: moderate; Grade 3: severe or medically significant. Higher grade indicates greater severity and an increase in CTCAE grade was defined relative to the Baseline grade. Corneal Events were to be examined.
CE Phase: Progression-free Survival (PFS)Up to 153 weeksPFS is defined as the time from randomization until the earliest date of confirmed progressive disease (PD) per IMWG, or death due to any cause.
CE Phase: Duration of Response (DoR)Up to 153 weeksDoR is defined as the time from first documented evidence or PR or better until progressive disease per IMWG or death due to progressive disease among participants who achieve confirmed partial response or better.
CE Phase: Time to Response (TTR)Up to 153 weeksTTR is defined as the time between the date of randomization and the first documented evidence of response (PR or better), among participants who achieve a response (confirmed PR or better).
CE Phase: Overall Survival (OS)Up to 153 weeksOS is defined as the time from randomization until death due to any cause.
CE Phase: Number of Participants With AEs and SAEsUp to 153 weeksAn adverse event (AE) is any untoward medical occurrence in a clinical study 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; 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 judged by physician, is associated with liver injury and impaired liver function. AEs and SAEs were to be coded using the Medical Dictionary for Regulatory Activities (MedDRA) coding system.
CE Phase: Number of Participants With AEs Leading to DiscontinuationUp to 153 weeksAn adverse event (AE) is any untoward medical occurrence in a clinical study participant, temporally associated with the use of a medicinal product, whether or not considered related to the medicinal product. Number of participants with AEs leading to discontinuation were to be evaluated.
CE Phase: Number of Participants With Dose Reduction or DelayUp to 153 weeksNumber of participants with dose reduction or delay were to be evaluated.
CE Phase: Number of Participants With Clinically Significant Changes in Hematology Lab ParametersUp to 153 weeksBlood samples were to be collected for the analysis of following hematology parameters: eosinophils, anemia, hemoglobin increased, lymphocyte count decreased, lymphocyte count increased, neutrophil count decreased, platelet count decreased, leukocytosis and white blood cell decreased. The laboratory parameters were to be graded according to Common Terminology Criteria for Adverse Events (CTCAE) version 5. Grade 1 (G1): mild; Grade 2 (G2): moderate; Grade 3 (G3): severe or medically significant. Higher grade indicates greater severity and an increase in CTCAE grade was defined relative to the Baseline grade.
CE Phase: Number of Participants With Clinically Significant Changes in Clinical Chemistry Lab ParametersUp to 153 weeksBlood samples were to be collected for the analysis of following chemistry parameters: Hypoglycemia, hypoalbuminemia, alkaline phosphatase (ALP) increased, alanine aminotransferase (ALT) increased, aspartate aminotransferase (AST) increased, blood bilirubin increased, creatine kinase (CPK) increased, creatinine increased, gamma glutamyl transferase (GGT) increased, hyperkalemia, blood lactate dehydrogenase (LDH) increased, hypermagnesemia, hypomagnesemia, hypernatremia, hypercalcemia, hypocalcemia and chronic kidney disease. The laboratory parameters were to be graded according to CTCAE version 5. G1: mild; G2: moderate; G3: severe or medically significant. Higher grade indicates greater severity and an increase in CTCAE grade was defined relative to the Baseline grade.
CE Phase: Concentration of ADAs Against Belantamab MafodotinUp to 153 weeksSerum samples were to be collected for the analysis of the presence of ADAs using validated immunoassays. All samples were to be further tested in screening assay, and positive samples were further to be characterized for antibody titers.
CE Phase: Clinical Benefit Rate (CBR)Up to 153 weeksClinical benefit rate was defined as the percentage of participants with a confirmed minimal response (MR) or better according to the IMWG Response Criteria. MR is \>= 25% but \< 49% reduction of serum M-protein and reduction in 24-hour urinary M-protein by 50-89%.
DE Phase: Percentage of Participants Achieving Stringent Complete Response (SCR), Complete Response (CR), Very Good Partial Response (VGPR) and Partial Response (PR)Up to 153 weeksPartial Response \[PR\], Very Good Partial Response \[VGPR\], Complete Response \[CR\], and stringent Complete Response \[sCR\] as assessed by the investigator per IMWG (2016). CR defined as negative immunofixation of serum and urine AND disappearance of any soft tissue plasmacytomas AND \<5% plasmacytomas in the bone marrow; sCR 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; VGPR 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; PR defined as ≥50% reduction of serum M-protein and reduction in 24-hour urinary M-protein by ≥90% or to \<200 mg/24 h.
CE Phase: Percentage of Participants Achieving SCR, CR, VGPR and PRUp to 153 weeksPartial Response \[PR\], Very Good Partial Response \[VGPR\], Complete Response \[CR\], and stringent Complete Response \[sCR\] as assessed by the investigator per IMWG (2016). 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.
DE Phase: Belantamab Mafodotin Concentrations for Plasma Antibody-Drug Conjugate (ADC)Predose, end of infusion (EOI), 2, and 24 hours postdose on Cycle 1 Day 1, and at Cycle 1 Day 4, Day 8, Day 22, Predose and EOI on Cycle 2 Day 1, Cycle 4 Day 1, and at end of treatment (approximately 153 weeks)Blood samples were collected for PK analysis of belantamab mafodotin Antibody-Drug Conjugate (ADC) when administered intravenously in combination with dostarlimab.

Countries

France, South Korea

Participant flow

Recruitment details

This is a sub study of the master study NCT04126200. This sub study was terminated due to lack of efficacy. The study was planned to include two phases - Dose Escalation (DE) and Cohort Expansion (CE) and no participants from this sub study were enrolled in CE phase as study was early terminated.

Participants by arm

ArmCount
1.9 mg/kg Belantamab Mafodotin + 500mg Dostarlimab
Participants with Relapsed/Refractory Multiple Myeloma (RRMM) received 1.9 milligram (mg)/kilogram (kg) belantamab mafodotin intravenous (IV) infusion as powder for solution once every 3 weeks (Q3W) infused over 30- 60 minutes on day 1 of 21-day cycles in combination with 500 mg dostarlimab as a 30-minute IV infusion 1 hour after belantamab mafodotin end of infusion (EOI) on day 1 of 21-day cycles (Q3W).
4
Total4

Withdrawals & dropouts

PeriodReasonFG000
Overall StudyWithdrawal by Subject1

Baseline characteristics

Characteristic1.9 mg/kg Belantamab Mafodotin + 500mg Dostarlimab
Age, Continuous70.0 YEAR
STANDARD_DEVIATION 9.83
Race/Ethnicity, Customized
Others
4 Participants
Sex/Gender, Customized
Males and Females
4 Participants

Adverse events

Event typeEG000
affected / at risk
deaths
Total, all-cause mortality
2 / 4
other
Total, other adverse events
4 / 4
serious
Total, serious adverse events
2 / 4

Outcome results

Primary

CE Phase: Overall Response Rate (ORR)

Overall Response Rate (ORR) was defined as the percentage of participants with a confirmed PR or better as the best overall response (i.e., Partial Response \[PR\], 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). CR defined as negative immunofixation of serum and urine AND disappearance of any soft tissue plasmacytomas AND \<5% plasmacytomas in the bone marrow; sCR 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; VGPR 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; PR defined as ≥50% reduction of serum M-protein and reduction in 24-hour urinary M-protein by ≥90% or to \<200 mg/24 h.

Time frame: Up to 26 weeks

Population: No participants were enrolled in CE Phase as study was terminated.

Primary

DE Phase: Number of Participants With Adverse Events (AEs)

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.

Time frame: Up to 153 weeks

Population: Safety population included all participants who received at least 1 dose of any component of the combination therapy.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Adverse Events (AEs)4 Participants
Primary

DE Phase: Number of Participants With Dose Limiting Toxicities (DLT)

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 DLTs. Severity was graded using National Cancer Institute - Common Terminology Criteria for Adverse Events (version 5.0).

Time frame: Up to 21 days

Population: DLT Evaluable Population included participants in DE who have received the first course of treatment containing both agents within a sub-study and followed up within cycle 1 (Each cycle is of 21 days) or withdrew within cycle 1 due to an AE meeting the definition of a DLT.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Dose Limiting Toxicities (DLT)1 Participants
Primary

DE Phase: Number of Participants With Worst-Case Chemistry Results by Maximum Grade Increase Post - Baseline Relative to Baseline

Blood samples were collected for the analysis of following chemistry parameters: Hypoglycemia, hypoalbuminemia, alkaline phosphatase (ALP) increased, alanine aminotransferase (ALT) increased, aspartate aminotransferase (AST) increased, blood bilirubin increased, creatine kinase (CPK) increased, creatinine increased, gamma glutamyl transferase (GGT) increased, hyperkalemia, blood lactate dehydrogenase (LDH) increased, hypermagnesemia, hypomagnesemia, hypernatremia, hypercalcemia, hypocalcemia and chronic kidney disease. G1: mild; G2: moderate; G3: severe. 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 and G3 are presented. The laboratory parameters were graded according to CTCAE version 5.

Time frame: Baseline (Day 1) and up to 153 weeks

Population: Safety Population. Only those participants with data available at the specified categories were analyzed.

ArmMeasureGroupValue (COUNT_OF_PARTICIPANTS)
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Chemistry Results by Maximum Grade Increase Post - Baseline Relative to BaselineHypernatremia, Increase to Grade 10 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Chemistry Results by Maximum Grade Increase Post - Baseline Relative to BaselineHypernatremia, Increase to Grade 20 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Chemistry Results by Maximum Grade Increase Post - Baseline Relative to BaselineHypernatremia, Increase to Grade 30 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Chemistry Results by Maximum Grade Increase Post - Baseline Relative to BaselineHypercalcemia, Increase to Grade 11 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Chemistry Results by Maximum Grade Increase Post - Baseline Relative to BaselineHypercalcemia, Increase to Grade 20 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Chemistry Results by Maximum Grade Increase Post - Baseline Relative to BaselineHypercalcemia, Increase to Grade 30 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Chemistry Results by Maximum Grade Increase Post - Baseline Relative to BaselineHypocalcemia, Increase to Grade 10 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Chemistry Results by Maximum Grade Increase Post - Baseline Relative to BaselineHypocalcemia, Increase to Grade 20 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Chemistry Results by Maximum Grade Increase Post - Baseline Relative to BaselineHypocalcemia, Increase to Grade 30 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Chemistry Results by Maximum Grade Increase Post - Baseline Relative to BaselineChronic Kidney Disease, Increase to Grade 10 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Chemistry Results by Maximum Grade Increase Post - Baseline Relative to BaselineChronic Kidney Disease, Increase to Grade 20 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Chemistry Results by Maximum Grade Increase Post - Baseline Relative to BaselineChronic Kidney Disease, Increase to Grade 30 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Chemistry Results by Maximum Grade Increase Post - Baseline Relative to BaselineHypoglycemia, Increase to Grade 10 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Chemistry Results by Maximum Grade Increase Post - Baseline Relative to BaselineHypoglycemia, Increase to Grade 20 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Chemistry Results by Maximum Grade Increase Post - Baseline Relative to BaselineHypoglycemia, Increase to Grade 30 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Chemistry Results by Maximum Grade Increase Post - Baseline Relative to BaselineHypoalbuminemia, Increase to Grade 10 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Chemistry Results by Maximum Grade Increase Post - Baseline Relative to BaselineHypoalbuminemia, Increase to Grade 22 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Chemistry Results by Maximum Grade Increase Post - Baseline Relative to BaselineHypoalbuminemia, Increase to Grade 30 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Chemistry Results by Maximum Grade Increase Post - Baseline Relative to BaselineAlkaline phosphatase increased, Increase to Grade 10 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Chemistry Results by Maximum Grade Increase Post - Baseline Relative to BaselineAlkaline phosphatase increased, Increase to Grade 20 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Chemistry Results by Maximum Grade Increase Post - Baseline Relative to BaselineAlkaline phosphatase increased, Increase to Grade 30 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Chemistry Results by Maximum Grade Increase Post - Baseline Relative to BaselineAlanine aminotransferase increased, Increase to Grade 12 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Chemistry Results by Maximum Grade Increase Post - Baseline Relative to BaselineAlanine aminotransferase increased, Increase to Grade 21 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Chemistry Results by Maximum Grade Increase Post - Baseline Relative to BaselineAlanine aminotransferase increased, Increase to Grade 30 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Chemistry Results by Maximum Grade Increase Post - Baseline Relative to BaselineAspartate aminotransferase increased, Increase to Grade 12 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Chemistry Results by Maximum Grade Increase Post - Baseline Relative to BaselineAspartate aminotransferase increased, Increase to Grade 20 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Chemistry Results by Maximum Grade Increase Post - Baseline Relative to BaselineAspartate aminotransferase increased, Increase to Grade 31 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Chemistry Results by Maximum Grade Increase Post - Baseline Relative to BaselineBlood bilirubin increased, Increase to Grade 10 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Chemistry Results by Maximum Grade Increase Post - Baseline Relative to BaselineBlood bilirubin increased, Increase to Grade 21 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Chemistry Results by Maximum Grade Increase Post - Baseline Relative to BaselineBlood bilirubin increased, Increase to Grade 30 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Chemistry Results by Maximum Grade Increase Post - Baseline Relative to BaselineCPK increased, Increase to Grade 11 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Chemistry Results by Maximum Grade Increase Post - Baseline Relative to BaselineCPK increased, Increase to Grade 20 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Chemistry Results by Maximum Grade Increase Post - Baseline Relative to BaselineCPK increased, Increase to Grade 30 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Chemistry Results by Maximum Grade Increase Post - Baseline Relative to BaselineCreatinine increased, Increase to Grade 12 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Chemistry Results by Maximum Grade Increase Post - Baseline Relative to BaselineCreatinine increased, Increase to Grade 20 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Chemistry Results by Maximum Grade Increase Post - Baseline Relative to BaselineCreatinine increased, Increase to Grade 30 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Chemistry Results by Maximum Grade Increase Post - Baseline Relative to BaselineGGT increased, Increase to Grade 11 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Chemistry Results by Maximum Grade Increase Post - Baseline Relative to BaselineGGT increased, Increase to Grade 20 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Chemistry Results by Maximum Grade Increase Post - Baseline Relative to BaselineGGT increased, Increase to Grade 30 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Chemistry Results by Maximum Grade Increase Post - Baseline Relative to BaselineHyperkalemia, Increase to Grade 10 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Chemistry Results by Maximum Grade Increase Post - Baseline Relative to BaselineHyperkalemia, Increase to Grade 20 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Chemistry Results by Maximum Grade Increase Post - Baseline Relative to BaselineHyperkalemia, Increase to Grade 30 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Chemistry Results by Maximum Grade Increase Post - Baseline Relative to BaselineBlood lactate dehydrogenase increased, Increase to Grade 14 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Chemistry Results by Maximum Grade Increase Post - Baseline Relative to BaselineBlood lactate dehydrogenase increased, Increase to Grade 20 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Chemistry Results by Maximum Grade Increase Post - Baseline Relative to BaselineBlood lactate dehydrogenase increased, Increase to Grade 30 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Chemistry Results by Maximum Grade Increase Post - Baseline Relative to BaselineHypermagnesemia, Increase to Grade 11 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Chemistry Results by Maximum Grade Increase Post - Baseline Relative to BaselineHypermagnesemia, Increase to Grade 20 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Chemistry Results by Maximum Grade Increase Post - Baseline Relative to BaselineHypermagnesemia, Increase to Grade 30 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Chemistry Results by Maximum Grade Increase Post - Baseline Relative to BaselineHypomagnesemia, Increase to Grade 10 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Chemistry Results by Maximum Grade Increase Post - Baseline Relative to BaselineHypomagnesemia, Increase to Grade 20 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Chemistry Results by Maximum Grade Increase Post - Baseline Relative to BaselineHypomagnesemia, Increase to Grade 30 Participants
Primary

DE Phase: Number of Participants With Worst-Case Hematology Results by Maximum Grade Increase Post - Baseline Relative to Baseline

Blood samples were collected for the analysis of following hematology parameters: eosinophils, anemia, hemoglobin increased, lymphocyte count decreased, lymphocyte count increased, neutrophil count decreased, platelet count decreased, leukocytosis and white blood cell decreased. 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. The laboratory parameters were graded according to Common Terminology Criteria for Adverse Events (CTCAE) version 5.

Time frame: Baseline (Day 1) and up to 153 weeks

Population: Safety Population.

ArmMeasureGroupValue (COUNT_OF_PARTICIPANTS)
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Hematology Results by Maximum Grade Increase Post - Baseline Relative to BaselineAnemia, Increase to Grade 10 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Hematology Results by Maximum Grade Increase Post - Baseline Relative to BaselineAnemia, Increase to Grade 21 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Hematology Results by Maximum Grade Increase Post - Baseline Relative to BaselineAnemia, Increase to Grade 31 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Hematology Results by Maximum Grade Increase Post - Baseline Relative to BaselineAnemia, Increase to Grade 40 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Hematology Results by Maximum Grade Increase Post - Baseline Relative to BaselineHemoglobin increased, Increase to Grade 10 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Hematology Results by Maximum Grade Increase Post - Baseline Relative to BaselineHemoglobin increased, Increase to Grade 21 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Hematology Results by Maximum Grade Increase Post - Baseline Relative to BaselineHemoglobin increased, Increase to Grade 30 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Hematology Results by Maximum Grade Increase Post - Baseline Relative to BaselineHemoglobin increased, Increase to Grade 40 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Hematology Results by Maximum Grade Increase Post - Baseline Relative to BaselineNeutrophil count decreased, Increase to Grade 31 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Hematology Results by Maximum Grade Increase Post - Baseline Relative to BaselineNeutrophil count decreased, Increase to Grade 41 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Hematology Results by Maximum Grade Increase Post - Baseline Relative to BaselineLymphocyte count decreased, Increase to Grade 10 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Hematology Results by Maximum Grade Increase Post - Baseline Relative to BaselineLymphocyte count decreased, Increase to Grade 20 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Hematology Results by Maximum Grade Increase Post - Baseline Relative to BaselineLymphocyte count decreased, Increase to Grade 30 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Hematology Results by Maximum Grade Increase Post - Baseline Relative to BaselineLymphocyte count decreased, Increase to Grade 42 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Hematology Results by Maximum Grade Increase Post - Baseline Relative to BaselineLymphocyte count increased, Increase to Grade 10 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Hematology Results by Maximum Grade Increase Post - Baseline Relative to BaselineLymphocyte count increased, Increase to Grade 21 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Hematology Results by Maximum Grade Increase Post - Baseline Relative to BaselineLymphocyte count increased, Increase to Grade 30 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Hematology Results by Maximum Grade Increase Post - Baseline Relative to BaselineLymphocyte count increased, Increase to Grade 40 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Hematology Results by Maximum Grade Increase Post - Baseline Relative to BaselineNeutrophil count decreased, Increase to Grade 10 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Hematology Results by Maximum Grade Increase Post - Baseline Relative to BaselineNeutrophil count decreased, Increase to Grade 21 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Hematology Results by Maximum Grade Increase Post - Baseline Relative to BaselineEosinophilia, Increase to Grade 10 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Hematology Results by Maximum Grade Increase Post - Baseline Relative to BaselineEosinophilia, Increase to Grade 20 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Hematology Results by Maximum Grade Increase Post - Baseline Relative to BaselineEosinophilia, Increase to Grade 30 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Hematology Results by Maximum Grade Increase Post - Baseline Relative to BaselineEosinophilia, Increase to Grade 40 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Hematology Results by Maximum Grade Increase Post - Baseline Relative to BaselinePlatelet count decreased, Increase to Grade 11 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Hematology Results by Maximum Grade Increase Post - Baseline Relative to BaselinePlatelet count decreased, Increase to Grade 20 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Hematology Results by Maximum Grade Increase Post - Baseline Relative to BaselinePlatelet count decreased, Increase to Grade 32 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Hematology Results by Maximum Grade Increase Post - Baseline Relative to BaselinePlatelet count decreased, Increase to Grade 40 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Hematology Results by Maximum Grade Increase Post - Baseline Relative to BaselineLeukocytosis, Increase to Grade 10 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Hematology Results by Maximum Grade Increase Post - Baseline Relative to BaselineLeukocytosis, Increase to Grade 20 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Hematology Results by Maximum Grade Increase Post - Baseline Relative to BaselineLeukocytosis, Increase to Grade 30 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Hematology Results by Maximum Grade Increase Post - Baseline Relative to BaselineLeukocytosis, Increase to Grade 40 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Hematology Results by Maximum Grade Increase Post - Baseline Relative to BaselineWhite blood cell decreased, Increase to Grade 10 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Hematology Results by Maximum Grade Increase Post - Baseline Relative to BaselineWhite blood cell decreased, Increase to Grade 20 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Hematology Results by Maximum Grade Increase Post - Baseline Relative to BaselineWhite blood cell decreased, Increase to Grade 30 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Worst-Case Hematology Results by Maximum Grade Increase Post - Baseline Relative to BaselineWhite blood cell decreased, Increase to Grade 41 Participants
Secondary

CE Phase: Clinical Benefit Rate (CBR)

Clinical benefit rate was defined as the percentage of participants with a confirmed minimal response (MR) or better according to the IMWG Response Criteria. MR is \>= 25% but \< 49% reduction of serum M-protein and reduction in 24-hour urinary M-protein by 50-89%.

Time frame: Up to 153 weeks

Population: No participants were enrolled in CE Phase as study was terminated.

Secondary

CE Phase: Concentration of ADAs Against Belantamab Mafodotin

Serum samples were to be collected for the analysis of the presence of ADAs using validated immunoassays. All samples were to be further tested in screening assay, and positive samples were further to be characterized for antibody titers.

Time frame: Up to 153 weeks

Population: No participants were enrolled in CE Phase as study was terminated.

Secondary

CE Phase: Concentration of ADAs Against Dostarlimab When Administered in Combination With Belantamab Mafodotin

Serum samples were to be collected for the analysis of the presence of ADAs using validated immunoassays. All samples were to be further tested in screening assay, and positive samples were further to be characterized for antibody titers.

Time frame: Up to 153 weeks

Population: No participants were enrolled in CE Phase as study was terminated.

Secondary

CE Phase: Dostarlimab Concentration When Administered in Combination With Belantamab Mafodotin

Blood samples were to be collected for PK analysis of dostarlimab when administered intravenously in combination with belantamab mafodotin.

Time frame: Up to 153 weeks

Population: No participants were enrolled in CE Phase as study was terminated.

Secondary

CE Phase: Duration of Response (DoR)

DoR is defined as the time from first documented evidence or PR or better until progressive disease per IMWG or death due to progressive disease among participants who achieve confirmed partial response or better.

Time frame: Up to 153 weeks

Population: No participants were enrolled in CE Phase as study was terminated.

Secondary

CE Phase: Number of Participants With Adverse Events of Special Interest (AESI)

An adverse event (AE) is any untoward medical occurrence in a clinical study participant, temporally associated with the use of a medicinal product, whether or not considered related to the medicinal product. Adverse events of special interest (AESIs) were to be collected.

Time frame: Up to 153 weeks

Population: No participants were enrolled in CE Phase as study was terminated.

Secondary

CE Phase: Number of Participants With AEs and SAEs

An adverse event (AE) is any untoward medical occurrence in a clinical study 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; 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 judged by physician, is associated with liver injury and impaired liver function. AEs and SAEs were to be coded using the Medical Dictionary for Regulatory Activities (MedDRA) coding system.

Time frame: Up to 153 weeks

Population: No participants were enrolled in CE Phase as study was terminated.

Secondary

CE Phase: Number of Participants With AEs Leading to Discontinuation

An adverse event (AE) is any untoward medical occurrence in a clinical study participant, temporally associated with the use of a medicinal product, whether or not considered related to the medicinal product. Number of participants with AEs leading to discontinuation were to be evaluated.

Time frame: Up to 153 weeks

Population: No participants were enrolled in CE Phase as study was terminated.

Secondary

CE Phase: Number of Participants With Any Corneal Events by Maximum Grade as Per CTCAE Grade

The corneal events were to be graded according to CTCAE version 5. Grade 1: mild; Grade 2: moderate; Grade 3: severe or medically significant. Higher grade indicates greater severity and an increase in CTCAE grade was defined relative to the Baseline grade. Corneal Events were to be examined.

Time frame: Up to 153 weeks

Population: No participants were enrolled in CE Phase as study was terminated.

Secondary

CE Phase: Number of Participants With Clinically Significant Changes in Clinical Chemistry Lab Parameters

Blood samples were to be collected for the analysis of following chemistry parameters: Hypoglycemia, hypoalbuminemia, alkaline phosphatase (ALP) increased, alanine aminotransferase (ALT) increased, aspartate aminotransferase (AST) increased, blood bilirubin increased, creatine kinase (CPK) increased, creatinine increased, gamma glutamyl transferase (GGT) increased, hyperkalemia, blood lactate dehydrogenase (LDH) increased, hypermagnesemia, hypomagnesemia, hypernatremia, hypercalcemia, hypocalcemia and chronic kidney disease. The laboratory parameters were to be graded according to CTCAE version 5. G1: mild; G2: moderate; G3: severe or medically significant. Higher grade indicates greater severity and an increase in CTCAE grade was defined relative to the Baseline grade.

Time frame: Up to 153 weeks

Population: No participants were enrolled in CE Phase as study was terminated.

Secondary

CE Phase: Number of Participants With Clinically Significant Changes in Hematology Lab Parameters

Blood samples were to be collected for the analysis of following hematology parameters: eosinophils, anemia, hemoglobin increased, lymphocyte count decreased, lymphocyte count increased, neutrophil count decreased, platelet count decreased, leukocytosis and white blood cell decreased. The laboratory parameters were to be graded according to Common Terminology Criteria for Adverse Events (CTCAE) version 5. Grade 1 (G1): mild; Grade 2 (G2): moderate; Grade 3 (G3): severe or medically significant. Higher grade indicates greater severity and an increase in CTCAE grade was defined relative to the Baseline grade.

Time frame: Up to 153 weeks

Population: No participants were enrolled in CE Phase as study was terminated.

Secondary

CE Phase: Number of Participants With Dose Reduction or Delay

Number of participants with dose reduction or delay were to be evaluated.

Time frame: Up to 153 weeks

Population: No participants were enrolled in CE Phase as study was terminated.

Secondary

CE Phase: Number of Participants With Post-baseline Positive ADAs Against Belantamab Mafodotin

Serum samples were to be collected for the analysis of the presence of ADAs using validated immunoassays. All samples were to be further tested in screening assay, and positive samples were further to be characterized for antibody titers.

Time frame: Up to 153 weeks

Population: No participants were enrolled in CE Phase as study was terminated.

Secondary

CE Phase: Number of Participants With Post-baseline Positive ADAs Against Dostarlimab

Serum samples were to be collected for the analysis of the presence of ADAs using validated immunoassays. All samples were to be further tested in screening assay, and positive samples were further to be characterized for antibody titers.

Time frame: Up to 153 weeks

Population: No participants were enrolled in CE Phase as study was terminated.

Secondary

CE Phase: Overall Survival (OS)

OS is defined as the time from randomization until death due to any cause.

Time frame: Up to 153 weeks

Population: No participants were enrolled in CE Phase as study was terminated.

Secondary

CE Phase: Percentage of Participants Achieving SCR, CR, VGPR and PR

Partial Response \[PR\], Very Good Partial Response \[VGPR\], Complete Response \[CR\], and stringent Complete Response \[sCR\] as assessed by the investigator per IMWG (2016). 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.

Time frame: Up to 153 weeks

Population: No participants were enrolled in CE Phase as study was terminated.

Secondary

CE Phase: Plasma Concentration of Belantamab Mafodotin Plasma Total Antibody

Blood samples were to be collected for PK analysis of Belantamab mafodotin plasma total antibody.

Time frame: Up to 153 weeks

Population: No participants were enrolled in CE Phase as study was terminated.

Secondary

CE Phase: Plasma Concentrations of Belantamab Mafodotin Antibody-Drug Conjugate (ADC)

Blood samples were to be collected for PK analysis of Belantamab Mafodotin Antibody-Drug Conjugate (ADC).

Time frame: Up to 153 weeks

Population: No participants were enrolled in CE Phase as study was terminated.

Secondary

CE Phase: Plasma Concentrations of Belantamab Mafodotin Cys- Monomethyl Auristatin-F (Cys-mcMMAF)

Blood samples were to be collected for PK analysis of Belantamab Mafodotin Cys- Monomethyl Auristatin-F (Cys-mcMMAF)

Time frame: Up to 153 weeks

Population: No participants were enrolled in CE Phase as study was terminated.

Secondary

CE Phase: Progression-free Survival (PFS)

PFS is defined as the time from randomization until the earliest date of confirmed progressive disease (PD) per IMWG, or death due to any cause.

Time frame: Up to 153 weeks

Population: No participants were enrolled in CE Phase as study was terminated.

Secondary

CE Phase: Time to Response (TTR)

TTR is defined as the time between the date of randomization and the first documented evidence of response (PR or better), among participants who achieve a response (confirmed PR or better).

Time frame: Up to 153 weeks

Population: No participants were enrolled in CE Phase as study was terminated.

Secondary

DE Phase: Belantamab Mafodotin Concentrations for Plasma Antibody-Drug Conjugate (ADC)

Blood samples were collected for PK analysis of belantamab mafodotin Antibody-Drug Conjugate (ADC) when administered intravenously in combination with dostarlimab.

Time frame: Predose, end of infusion (EOI), 2, and 24 hours postdose on Cycle 1 Day 1, and at Cycle 1 Day 4, Day 8, Day 22, Predose and EOI on Cycle 2 Day 1, Cycle 4 Day 1, and at end of treatment (approximately 153 weeks)

Population: Pharmacokinetic population. Only those participants with data available at the specified data points were analyzed.

ArmMeasureGroupValue (MEDIAN)
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Belantamab Mafodotin Concentrations for Plasma Antibody-Drug Conjugate (ADC)CYCLE 1 DAY 1, PRE-DOSE0.0 Nanogram/ millilitre (ng/mL)
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Belantamab Mafodotin Concentrations for Plasma Antibody-Drug Conjugate (ADC)CYCLE 1 DAY 1, END OF INFUSION25300.0 Nanogram/ millilitre (ng/mL)
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Belantamab Mafodotin Concentrations for Plasma Antibody-Drug Conjugate (ADC)CYCLE 1 DAY 1, 2 HOURS26450.0 Nanogram/ millilitre (ng/mL)
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Belantamab Mafodotin Concentrations for Plasma Antibody-Drug Conjugate (ADC)CYCLE 1 DAY 1, 24 HOURS20400.0 Nanogram/ millilitre (ng/mL)
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Belantamab Mafodotin Concentrations for Plasma Antibody-Drug Conjugate (ADC)CYCLE 1 DAY 49110.0 Nanogram/ millilitre (ng/mL)
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Belantamab Mafodotin Concentrations for Plasma Antibody-Drug Conjugate (ADC)CYCLE 1 DAY 84830.0 Nanogram/ millilitre (ng/mL)
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Belantamab Mafodotin Concentrations for Plasma Antibody-Drug Conjugate (ADC)CYCLE 1 DAY 220.0 Nanogram/ millilitre (ng/mL)
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Belantamab Mafodotin Concentrations for Plasma Antibody-Drug Conjugate (ADC)CYCLE 2 DAY 1, PRE-DOSE1295.0 Nanogram/ millilitre (ng/mL)
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Belantamab Mafodotin Concentrations for Plasma Antibody-Drug Conjugate (ADC)CYCLE 2 DAY 1, END OF INFUSION41950.0 Nanogram/ millilitre (ng/mL)
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Belantamab Mafodotin Concentrations for Plasma Antibody-Drug Conjugate (ADC)CYCLE 4 DAY 1, PRE-DOSE0.0 Nanogram/ millilitre (ng/mL)
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Belantamab Mafodotin Concentrations for Plasma Antibody-Drug Conjugate (ADC)CYCLE 4 DAY 1, END OF INFUSION27600.0 Nanogram/ millilitre (ng/mL)
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Belantamab Mafodotin Concentrations for Plasma Antibody-Drug Conjugate (ADC)END OF TREATMENT0.0 Nanogram/ millilitre (ng/mL)
Secondary

DE Phase: Belantamab Mafodotin Concentrations for Plasma Cys-mcMMAF

Blood samples were collected for PK analysis of belantamab mafodotin cys-mcMMAF when administered intravenously in combination with dostarlimab.

Time frame: Predose, end of infusion (EOI), 2, and 24 hours postdose on Cycle 1 Day 1, and at Cycle 1 Day 4, Day 8, Day 22, Predose and EOI on Cycle 2 Day 1, Cycle 4 Day 1, and at end of treatment (approximately 153 weeks)

Population: Pharmacokinetic population. Only those participants with data available at the specified data points were analyzed.

ArmMeasureGroupValue (MEDIAN)
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Belantamab Mafodotin Concentrations for Plasma Cys-mcMMAFCYCLE 1 DAY 1, PRE-DOSE0.00 ng/mL
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Belantamab Mafodotin Concentrations for Plasma Cys-mcMMAFCYCLE 1 DAY 1, END OF INFUSION218.00 ng/mL
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Belantamab Mafodotin Concentrations for Plasma Cys-mcMMAFCYCLE 1 DAY 1, 2 HOURS376.00 ng/mL
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Belantamab Mafodotin Concentrations for Plasma Cys-mcMMAFCYCLE 1 DAY 1, 24 HOURS750.00 ng/mL
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Belantamab Mafodotin Concentrations for Plasma Cys-mcMMAFCYCLE 1 DAY 4549.50 ng/mL
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Belantamab Mafodotin Concentrations for Plasma Cys-mcMMAFCYCLE 1 DAY 8170.90 ng/mL
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Belantamab Mafodotin Concentrations for Plasma Cys-mcMMAFCYCLE 1 DAY 220.00 ng/mL
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Belantamab Mafodotin Concentrations for Plasma Cys-mcMMAFCYCLE 2 DAY 1, PRE-DOSE0.00 ng/mL
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Belantamab Mafodotin Concentrations for Plasma Cys-mcMMAFCYCLE 2 DAY 1, END OF INFUSION555.00 ng/mL
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Belantamab Mafodotin Concentrations for Plasma Cys-mcMMAFCYCLE 4 DAY 1, PRE-DOSE0.00 ng/mL
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Belantamab Mafodotin Concentrations for Plasma Cys-mcMMAFCYCLE 4 DAY 1, END OF INFUSION469.00 ng/mL
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Belantamab Mafodotin Concentrations for Plasma Cys-mcMMAFEND OF TREATMENT0.00 ng/mL
Secondary

DE Phase: Belantamab Mafodotin Concentrations for Plasma Total Antibody

Blood samples were collected for PK analysis of belantamab mafodotin total antibody when administered intravenously in combination with dostarlimab.

Time frame: Predose, end of infusion (EOI), 2, and 24 hours postdose on Cycle 1 Day 1, and at Cycle 1 Day 4, Day 8, Day 22, Predose and EOI on Cycle 2 Day 1, Cycle 4 Day 1, and at end of treatment (approximately 153 weeks)

Population: Pharmacokinetic population. Only those participants with data available at the specified data points were analyzed.

ArmMeasureGroupValue (MEDIAN)
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Belantamab Mafodotin Concentrations for Plasma Total AntibodyCYCLE 1 DAY 1, PRE-DOSE0.0 ng/mL
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Belantamab Mafodotin Concentrations for Plasma Total AntibodyCYCLE 1 DAY 1, END OF INFUSION31000.0 ng/mL
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Belantamab Mafodotin Concentrations for Plasma Total AntibodyCYCLE 1 DAY 1, 2 HOURS32400.0 ng/mL
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Belantamab Mafodotin Concentrations for Plasma Total AntibodyCYCLE 1 DAY 1, 24 HOURS21400.0 ng/mL
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Belantamab Mafodotin Concentrations for Plasma Total AntibodyCYCLE 1 DAY 415000.0 ng/mL
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Belantamab Mafodotin Concentrations for Plasma Total AntibodyCYCLE 1 DAY 88235.0 ng/mL
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Belantamab Mafodotin Concentrations for Plasma Total AntibodyCYCLE 1 DAY 221140.0 ng/mL
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Belantamab Mafodotin Concentrations for Plasma Total AntibodyCYCLE 2 DAY 1, PRE-DOSE3625.0 ng/mL
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Belantamab Mafodotin Concentrations for Plasma Total AntibodyCYCLE 2 DAY 1, END OF INFUSION45350.0 ng/mL
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Belantamab Mafodotin Concentrations for Plasma Total AntibodyCYCLE 4 DAY 1, PRE-DOSE2800.0 ng/mL
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Belantamab Mafodotin Concentrations for Plasma Total AntibodyCYCLE 4 DAY 1, END OF INFUSION48900.0 ng/mL
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Belantamab Mafodotin Concentrations for Plasma Total AntibodyEND OF TREATMENT628.0 ng/mL
Secondary

DE Phase: Concentration of ADAs Against Belantamab Mafodotin

Serum samples were collected for the analysis of the presence of ADAs using validated immunoassays. All samples were to be further tested in screening assay, and positive samples were further to be characterized for antibody titers.

Time frame: Up to 153 weeks

Population: Safety Population. Only those participants with positive post-baseline antibody against belantamab mafodotin were analyzed.

ArmMeasureValue (MEAN)
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Concentration of ADAs Against Belantamab MafodotinNA ng/mL
Secondary

DE Phase: Concentration of ADAs Against Dostarlimab When Administered in Combination With Belantamab Mafodotin

Serum samples were collected for the analysis of the presence of ADAs using validated immunoassays. All samples were to be further tested in screening assay, and positive samples were further to be characterized for antibody titers.

Time frame: Up to 153 weeks

Population: Safety Population. No participants were found positive for ADAs, hence participants were not analyzed for concentration of ADAs.

Secondary

DE Phase: Dostarlimab Concentration When Administered in Combination With Belantamab Mafodotin

Blood samples were collected for PK analysis of dostarlimab when administered intravenously in combination with belantamab mafodotin.

Time frame: Predose and end of infusion (EOI) on Cycle 1 Day 1, Cycle 2 Day 1, Cycle 5 Day 1, and at the end of treatment (approximately 153 weeks)

Population: Pharmacokinetic population included all participants in the Safety population who had at least 1 non-missing PK assessment. Only those participants with data available at the specified data points were analyzed.

ArmMeasureGroupValue (MEDIAN)
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Dostarlimab Concentration When Administered in Combination With Belantamab MafodotinCYCLE 1 DAY 1, PRE-DOSE0.0 ng/mL
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Dostarlimab Concentration When Administered in Combination With Belantamab MafodotinCYCLE 1 DAY 1, END OF INFUSION52500.0 ng/mL
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Dostarlimab Concentration When Administered in Combination With Belantamab MafodotinCYCLE 2 DAY 1, PRE-DOSE43550.0 ng/mL
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Dostarlimab Concentration When Administered in Combination With Belantamab MafodotinCYCLE 2 DAY 1, END OF INFUSION224000.0 ng/mL
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Dostarlimab Concentration When Administered in Combination With Belantamab MafodotinCYCLE 5 DAY 1, PRE-DOSE532.0 ng/mL
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Dostarlimab Concentration When Administered in Combination With Belantamab MafodotinCYCLE 5 DAY 1, END OF INFUSION312000.0 ng/mL
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Dostarlimab Concentration When Administered in Combination With Belantamab MafodotinEND OF TREATMENT35750.0 ng/mL
Secondary

DE Phase: Number of Participants With Adverse Events of Special Interest (AESI)

An adverse event (AE) is any untoward medical occurrence in a clinical study participant, temporally associated with the use of a medicinal product, whether or not considered related to the medicinal product. Adverse events of special interest (AESIs) were collected.

Time frame: Up to 153 weeks

Population: Safety Population.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Adverse Events of Special Interest (AESI)3 Participants
Secondary

DE Phase: Number of Participants With Any Corneal Event by Maximum Grade as Per CTCAE Grade

The corneal events were graded according to CTCAE version 5. Grade 1: mild; Grade 2: moderate; Grade 3: severe or medically significant. Higher grade indicates greater severity and an increase in CTCAE grade was defined relative to the Baseline grade. Results are presented for number of participants with any corneal events by maximum grade as per CTCAE grade.

Time frame: Up to 153 weeks

Population: Safety Population

ArmMeasureGroupValue (COUNT_OF_PARTICIPANTS)
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Any Corneal Event by Maximum Grade as Per CTCAE GradeGrade 11 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Any Corneal Event by Maximum Grade as Per CTCAE GradeGrade 20 Participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Any Corneal Event by Maximum Grade as Per CTCAE GradeGrade 30 Participants
Secondary

DE Phase: Number of Participants With Post-baseline Positive ADAs Against Dostarlimab

Serum samples were collected for the analysis of the presence of ADAs using validated immunoassays. All samples were tested in screening assay, and positive samples were further characterized for antibody titers.

Time frame: Up to 153 weeks

Population: Safety Population.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Post-baseline Positive ADAs Against Dostarlimab0 Participants
Secondary

DE Phase: Number of Participants With Post-baseline Positive Anti-drug Antibodies (ADAs) Against Belantamab Mafodotin

Serum samples were collected for the analysis of the presence of ADAs using validated immunoassays. All samples were tested in screening assay, and positive samples were further characterized for antibody titers.

Time frame: Up to 153 weeks

Population: Safety Population

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Number of Participants With Post-baseline Positive Anti-drug Antibodies (ADAs) Against Belantamab Mafodotin1 Participants
Secondary

DE Phase: Overall Response Rate (ORR)

Overall Response Rate (ORR) was defined as the percentage of participants with a confirmed PR or better as the best overall response (i.e., Partial Response \[PR\], 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). CR defined as negative immunofixation of serum and urine AND disappearance of any soft tissue plasmacytomas AND \<5% plasmacytomas in the bone marrow; sCR 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; VGPR 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; PR defined as ≥50% reduction of serum M-protein and reduction in 24-hour urinary M-protein by ≥90% or to \<200 mg/24 h.

Time frame: Up to 153 weeks

Population: Safety Population

ArmMeasureValue (NUMBER)
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Overall Response Rate (ORR)25 Percentage of participants
Secondary

DE Phase: Percentage of Participants Achieving Stringent Complete Response (SCR), Complete Response (CR), Very Good Partial Response (VGPR) and Partial Response (PR)

Partial Response \[PR\], Very Good Partial Response \[VGPR\], Complete Response \[CR\], and stringent Complete Response \[sCR\] as assessed by the investigator per IMWG (2016). CR defined as negative immunofixation of serum and urine AND disappearance of any soft tissue plasmacytomas AND \<5% plasmacytomas in the bone marrow; sCR 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; VGPR 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; PR defined as ≥50% reduction of serum M-protein and reduction in 24-hour urinary M-protein by ≥90% or to \<200 mg/24 h.

Time frame: Up to 153 weeks

Population: Safety Population

ArmMeasureGroupValue (NUMBER)
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Percentage of Participants Achieving Stringent Complete Response (SCR), Complete Response (CR), Very Good Partial Response (VGPR) and Partial Response (PR)Stringent Complete Response (sCR)0 Percentage of participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Percentage of Participants Achieving Stringent Complete Response (SCR), Complete Response (CR), Very Good Partial Response (VGPR) and Partial Response (PR)Complete Response (CR)0 Percentage of participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Percentage of Participants Achieving Stringent Complete Response (SCR), Complete Response (CR), Very Good Partial Response (VGPR) and Partial Response (PR)Very Good Partial Response (VGPR)25 Percentage of participants
1.9 mg/kg Belantamab Mafodotin + 500mg DostarlimabDE Phase: Percentage of Participants Achieving Stringent Complete Response (SCR), Complete Response (CR), Very Good Partial Response (VGPR) and Partial Response (PR)Partial Response (PR)0 Percentage of participants

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026