A Phase Ib Multi-Cohort Trial of MK-3475 (Pembrolizumab) in Subjects With Hematologic Malignancies

Complete Remission Rate (CRR) in Cohort 3: Relapsed/Refractory (R/R) Hodgkin Lymphoma (HL)

Time Frame: Up to approximately 78.5 months

CRR was defined as the percentage of participants with complete remission according to the revised response criteria for malignant lymphoma per Cheson et al. 2007. Complete remission was demonstrated by disappearance of all evidence of disease in the bone marrow, spleen, liver, and lymph nodes. Cohort 3 was evaluated statistically by comparing the complete remission for pembrolizumab to a fixed efficacy target of 10% using a binomial exact test. The percentage of participants with complete remission as assessed by the investigator is presented.

Number of Participants Who Experienced One or More Adverse Events (AEs):

Time Frame: Up to approximately 78.5 months

An adverse event was defined as any untoward medical occurrence in a participant administered study treatment and did not necessarily have a causal relationship with this treatment. An adverse event could be any unfavorable and unintended sign (including an abnormal laboratory finding), symptom, or disease temporally associated with the use of a medicinal product or protocol-specified procedure, whether or not considered related to the medicinal product or protocol-specified procedure. Any worsening of a preexisting condition that was temporally associated with the use of the study treatment was also an adverse event.

Number of Participants Who Discontinued Study Treatment Due to an Adverse Event (AE)

Time Frame: Up to approximately 78.5 months

An adverse event was defined as any untoward medical occurrence in a participant administered study treatment and did not necessarily have a causal relationship with this treatment. An adverse event could be any unfavorable and unintended sign (including an abnormal laboratory finding), symptom, or disease temporally associated with the use of a medicinal product or protocol-specified procedure, whether or not considered related to the medicinal product or protocol-specified procedure. Any worsening of a preexisting condition that was temporally associated with the use of the study treatment was also an adverse event.

Objective Response Rate (ORR) in Cohort 1: Myelodysplastic Syndrome (MDS)

Time Frame: Up to approximately 78.5 months

ORR was defined as the percentage of participants with response (complete response \[CR\] or partial response \[PR\]) according to the International Working Group (IWG) response criteria in myelodysplasia per Cheson et al. 2006. CR was demonstrated by ≤5% myeloblasts with normal maturation of all cell lines in the bone marrow (persistent dysplasia will be noted) and normal findings for hemoglobin, platelet count, neutrophil count, and absence of blasts in the blood. PR was all CR criteria if abnormal before treatment except bone marrow blasts decreased by ≥50% over pre-treatment but still \>5%. Cellularity and morphology are not relevant. Cohort 1 was evaluated statistically by comparing the ORR for pembrolizumab to a fixed efficacy target of 10% using a binomial exact test. The percentage of participants with CR and PR as assessed by the investigator is presented.

Objective Response Rate (ORR) in Cohort 2: Relapsed Refractory/Refractory (rR/R) Multiple Myeloma (MM)

Time Frame: Up to approximately 78.5 months

ORR was defined as the percentage of the participants with either a stringent complete response (sCR), complete response (CR), very good partial response (VGPR), or partial response (PR) according to the International Myeloma Working Group (IMWG) 2006 response criteria. CR=negative immunofixation of serum and urine+disappearance of soft tissue plasmacytomas+≤5% plasma cells in the bone marrow (BM); sCR=stringent complete response, CR as above+normal serum free light-chain ratio and absence of clonal cells in BM; VGPR=serum+urine M-protein (M-p) by immunofixation but not on electrophoresis OR ≥ 90% reduction in serum M-p+urine M-p \<100 mg/24 hr; PR=≥50% reduction of serum M-p+reduction in 24-hour urine M-p by ≥90% or to \<200 mg/24 hours. Cohort 2 was evaluated statistically by comparing the ORR for pembrolizumab to a fixed efficacy target of 25% using a binomial exact test. The percentage of participants with CR, sCR, PR, VGPR as assessed by the investigator is presented.

Objective Response Rate (ORR) in Participants Pooled From the Cohort 4 Non-Hodgkin Lymphoma (NHL) Sub-Cohorts (Cohorts 4A+4B+4C+4D)

Time Frame: Up to approximately 78.5 months

ORR was defined as the percentage of participants with response (complete response \[CR\] or partial response \[PR\]) according to the revised response criteria for malignant lymphoma per Cheson et al. 2007. CR was demonstrated by disappearance of all evidence of disease in the bone marrow, spleen, liver, and lymph nodes. PR was \>50% decrease in the sum of product diameters (SPD) for ≤6 target masses for lymph nodes and \>50% decrease in SPD for a single nodule in greatest transverse diameter for spleen and liver, and no size increase in the lymph nodes, spleen, or liver. The pooled Cohort 4 sub-cohorts were evaluated statistically by comparing the ORR for pembrolizumab to a fixed efficacy target of 25% using a binomial exact test. The percentage of participants with CR and PR as assessed by the investigator is presented.

Objective Response Rate (ORR) in the Cohort 4 Non-Hodgkin Lymphoma (NHL) Individual Sub-Cohorts (Cohorts 4A, 4B, 4C, and 4D)

Time Frame: Up to approximately 78.5 months

ORR was evaluated for each of the Cohort 4 sub-cohorts: 4A (primary mediastinal B-cell lymphoma), 4B (grey zone, splenic marginal zone, and mantle cell lymphomas), 4C (follicular lymphoma), and 4D (diffuse large B-Cell lymphoma). ORR was defined as the percentage of participants with response (complete response \[CR\] or partial response \[PR\]) according to the revised response criteria for malignant lymphoma per Cheson et al. 2007. CR was demonstrated by disappearance of all evidence of disease in the bone marrow, spleen, liver, and lymph nodes. PR was \>50% decrease in the sum of product diameters (SPD) for ≤6 target masses for lymph nodes and \>50% decrease in SPD for a single nodule in greatest transverse diameter for spleen and liver, and no size increase in the lymph nodes, spleen, or liver. Per protocol, Cohorts 4A, 4B, 4C, and 4D were not planned to be compared to an efficacy target. The percentage of participants with CR and PR as assessed by the investigator is presented.

Objective Response Rate (ORR) in Participants Pooled From Cohort 5 (Pembrolizumab + 20 or 25 mg Doses of Lenalidomide) Relapsed/Refractory (R/R) Diffuse Large B-Cell Lymphoma (DLBCL)

Time Frame: Up to approximately 78.5 months

ORR was defined as the percentage of participants with response (complete response \[CR\] or partial response \[PR\]) according to the revised response criteria for malignant lymphoma per Cheson et al. 2007. CR was demonstrated by disappearance of all evidence of disease in the bone marrow, spleen, liver, and lymph nodes. PR was \>50% decrease in the sum of product diameters (SPD) for ≤6 target masses for lymph nodes and \>50% decrease in SPD for a single nodule in greatest transverse diameter for spleen and liver, and no size increase in the lymph nodes, spleen, or liver. Per protocol, pooled Cohort 5 was not planned to be evaluated statistically compared to a fixed efficacy target. The percentage of participants with CR and PR as assessed by the investigator is presented.