Study of Vibostolimab Alone and in Combination With Pembrolizumab in Advanced Solid Tumors (MK-7684-001) ( KEYVIBE-001)

Phase 1

Completed

Conditions: Neoplasms

Interventions: Biological: vibostolimab
Biological: pembrolizumab/vibostolimab coformulation
Biological: pembrolizumab
Drug: pemetrexed
Drug: carboplatin
Drug: cisplatin
Drug: etoposide

Registration Number: NCT02964013

Lead Sponsor: Merck Sharp & Dohme LLC

Brief Summary: This is a safety, efficacy, and pharmacokinetics (PK) study of vibostolimab (MK-7684) as monotherapy and in combination with pembrolizumab (MK-3475) or pembrolizumab plus pemetrexed and carboplatin in adults with metastatic solid tumors for which there is no available therapy that is expected to convey clinical benefit. Part A of this study is a dose escalation and confirmation phase to estimate the recommended Phase 2 dose (RPTD) for vibostolimab monotherapy or in combination with pembrolizumab, pemetrexed, and carboplatin. Part A will also evaluate the anti-tumor activity of vibostolimab in combination with pembrolizumab plus pemetrexed and carboplatin in participants with non-small cell lung cancer (NSCLC) and vibostolimab (at two dose levels) in combination with pembrolizumab in Japanese participants with gastric cancer. Part B will evaluate the anti-tumor activity of vibostolimab at the RPTD when used as monotherapy and in combination with pembrolizumab in participants with advanced solid tumors in a non-randomized study design. Part B will also evaluate 2 doses of vibostolimab in combination with pembrolizumab in participants with programmed death 1 (PD-1) treatment naïve cancer using a 1:1 randomized study design. Part B is expanded with Amendment 11 to include an additional arm that will compare the safety and PK of a fixed dose of pembrolizumab/vibostolimab coformulation (MK-7684A) to vibostolimab in combination with pembrolizumab administered as separate intravenous infusions. Part A is expanded with Amendment 12 to include an additional arm that will compare the safety and PK of vibostolimab plus pembrolizumab plus the investigator's choice of platinum agent (carboplatin or cisplatin), and etoposide. Part B is expanded with Amendment 12 to include evaluation of efficacy of vibostolimab plus pembrolizumab plus the investigator's choice of platinum agent (carboplatin or cisplatin), and etoposide and efficacy of pembrolizumab/vibostolimab coformulation in participants from mainland China. The primary hypotheses are that vibostolimab administered as monotherapy or in combination with pembrolizumab is safe and tolerable when administered at the RPTD and that pembrolizumab/vibostolimab coformulation is safe and tolerable when administered as a fixed dose.

Detailed Description: Not available

Recruitment & Eligibility

Status: COMPLETED

Sex: All

Target Recruitment: 474

Inclusion Criteria

For Part A participants enrolled prior to Amendment 7, must have a histologically or cytologically confirmed metastatic solid tumor for which there is no available therapy that is expected to convey clinical benefit
For Part A Japanese cohort added with Amendment 7: Must reside in Japan and be of Japanese descent and have adenocarcinoma of the stomach and/or gastric-esophageal junction (GEJ) that is considered inoperable and that has received, and progressed on, at least 1 prior chemotherapy regimen or human epidermal growth factor receptor 2 (HER2)/neu-targeted approved therapy (if HER2/neu-positive). In both cases, participants may be untreated or could have received and progressed on 1 prior regimen, but must not have received prior anti-PD-1/PD-L1 therapy
For Part A participants with non-small cell lung cancer (NSCLC) added with Amendment 7: Must have a histologically or cytologically confirmed diagnosis of stage IV (M1a or M1b per current American Joint Committee on Cancer criteria, edition 8) non-squamous NSCLC
For Part B China participants added with Amendment 12. Must have a histologically or cytologically confirmed metastatic solid tumor for which no more than 2 prior lines of therapy were administered and there is no available therapy that is expected to convey clinical benefit AND be Chinese from mainland China
For Parts A and B: Has histologically or cytologically confirmed metastatic solid tumor
Has measurable disease by Response Evaluation Criteria In Solid Tumors (RECIST)
Has an Eastern Cooperative Oncology Group performance status of 0 to 1
Females must not be pregnant
Women of childbearing potential and male participants must agree to use adequate contraception for the course of the study
Has provided a tumor tissue sample (archival or newly obtained core or excisional biopsy of a tumor lesion)
For Chinese participants enrolled as part of Amendment 12. No tumor tissue samples will be collected

Exclusion Criteria

Has had chemotherapy, radiation, biological cancer therapy or major surgery within 4 weeks prior to the first dose of study treatment
Has not recovered to Common Toxicity Criteria for Adverse Events Grade 1 or better from the adverse events due to cancer therapeutics administered more than 4 weeks prior to the first dose of study treatment
Is currently participating in or has participated in a study of an investigational agent or has used an investigational device within 4 weeks prior to the first dose of study treatment
Has received previous treatment with another agent targeting the T cell immunoglobulin and immunoreceptor tyrosine-based inhibitory motif (TIGIT) receptor
Has received previous treatment with an immunomodulatory agent (e.g., anti-programmed cell death 1, anti-programmed cell death ligand 1 or cytotoxic T-lymphocyte-associated protein 4) and was discontinued from that treatment due to a Grade 3 or higher immune-related adverse event
Is expected to require any other form of antineoplastic therapy while participating in the trial
Is on chronic systemic steroid therapy in excess of replacement doses or on any other form of immunosuppressive medication
Has a history of a previous additional malignancy unless potentially curative treatment has been completed with no evidence of malignancy for 5 years
Has known active central nervous system (CNS) metastases and/or carcinomatous meningitis
Has an active autoimmune disease
Has an active infection requiring systemic treatment
Has interstitial lung disease
Has active or past history of (non-infectious) pneumonitis requiring steroids
Has symptomatic ascites or pleural effusion
Has previously had a hematopoetic stem cell transplant or solid organ transplant
Is known to be human immunodeficiency virus (HIV) positive and/or known to have active chronic or acute Hepatitis B or Hepatitis C
Has a known psychiatric and/or substance abuse disorder that would make it difficult for the participant to cooperate with the requirements of the trial
Is a regular user (including recreational use) of any illicit drugs at the time of providing documented informed consent, or has a recent history (within the last year) of substance abuse
Has received a live virus vaccine within 30 days prior to the first dose of study treatment
Has had hormonal cancer therapy (e.g., tamoxifen, leuprolide). within 4 weeks prior to the first dose of study treatment
For Part A participants with NSCLC added with Amendment 7: Is unable to interrupt aspirin or other nonsteroidal anti-inflammatory drugs (NSAIDs) other than an aspirin dose ≤1.3 gram per day for a 5-day period (8-day period for long-acting agents, such as piroxicam)
For Part A participants with NSCLC added with Amendment 7: Is unable or unwilling to take folic acid or Vitamin B12 supplementation

Study & Design

Study Type: INTERVENTIONAL

Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
vibostolimab + pembrolizumab	vibostolimab	During an initial dose evaluation phase, participants will receive Dose A, B, C, D, E, or F of vibostolimab in combination with 200 mg pembrolizumab on Day 1 of each 21-day infusion cycle (for a maximum of 35 cycles) until the RPTD of vibostolimab has been established. The RPTD will be established based on the number of DLTs at each dose level. Once the RPTD of vibostolimab is established, participants will continue receiving the RPTD of vibostolimab in combination with 200 mg pembrolizumab on Day 1 of each 21-day infusion cycle until the 35-cycle limit is reached.
Advanced solid tumor cohort	pembrolizumab	Participants will receive the RPTD of vibostolimab monotherapy or the RPTD of vibostolimab in combination with 200 mg pembrolizumab on Day 1 of each 21-day infusion cycle until the 35-cycle limit is reached.
Advanced solid tumor cohort	vibostolimab	Participants will receive the RPTD of vibostolimab monotherapy or the RPTD of vibostolimab in combination with 200 mg pembrolizumab on Day 1 of each 21-day infusion cycle until the 35-cycle limit is reached.
Randomized dose 1 comparison cohort	pembrolizumab	Participants will be randomized to receive a fixed dose (Dose 1) of vibostolimab in combination with 200 mg pembrolizumab on Day 1 of each 21-day infusion cycle until the 35-cycle limit is reached.
vibostolimab	vibostolimab	During an initial dose evaluation phase, participants will receive Dose A, B, C, D, E, or F of vibostolimab on Day 1 of each 21-day infusion cycle (for a maximum of 35 cycles) until the RPTD has been established. The RPTD will be established based on the number of dose limiting toxicities (DLTs) at each dose level. Once the RPTD is established, participants will continue receiving the RPTD of vibostolimab on Day 1 of each 21-day infusion cycle until the 35-cycle limit is reached.
vibostolimab + pembrolizumab	pembrolizumab	During an initial dose evaluation phase, participants will receive Dose A, B, C, D, E, or F of vibostolimab in combination with 200 mg pembrolizumab on Day 1 of each 21-day infusion cycle (for a maximum of 35 cycles) until the RPTD of vibostolimab has been established. The RPTD will be established based on the number of DLTs at each dose level. Once the RPTD of vibostolimab is established, participants will continue receiving the RPTD of vibostolimab in combination with 200 mg pembrolizumab on Day 1 of each 21-day infusion cycle until the 35-cycle limit is reached.
vibostolimab +pembrolizumab+pemetrexed+carboplatin	vibostolimab	Participants will receive a fixed dose of vibostolimab in combination with 200 mg pembrolizumab, 500 mg/m\^2 pemetrexed, and Area Under Curve (AUC) 5 mg/mL/min carboplatin on Day 1 of each 21-day infusion cycle for up to 4 cycles followed by maintenance therapy with a fixed dose of vibostolimab in combination with 200 mg pembrolizumab and 500 mg/m\^2 pemetrexed on Day 1 of each 21-day infusion cycle for up to an additional 31 cycles.
vibostolimab Dose 1 Japanese cohort	vibostolimab	Japanese participants will be randomized to receive a fixed dose (Dose 1) of vibostolimab in combination with 200 mg pembrolizumab on Day 1 of each 21-day infusion cycle until the 35-cycle limit is reached.
Randomized dose 1 comparison cohort	vibostolimab	Participants will be randomized to receive a fixed dose (Dose 1) of vibostolimab in combination with 200 mg pembrolizumab on Day 1 of each 21-day infusion cycle until the 35-cycle limit is reached.
vibostolimab+pembrolizumab+carboplatin OR cisplatin+etoposide	vibostolimab	Participants will receive 200 mg vibostolimab in combination with 200 mg pembrolizumab, plus the investigator's choice of Area Under Curve (AUC) 5 mg/mL/min carboplatin OR 75 mg/m\^2 cisplatin on Day 1 of each 21-day cycle plus 100 mg/m\^2/day etoposide on Days 1-3 of each 21-day cycle for up to 4 cycles. Maintenance therapy with 200 mg vibostolimab in combination with 200 mg pembrolizumab on Day 1 of each 21-day cycle will continue for up to an additional 31 cycles. A participant will be allowed to switch from cisplatin to carboplatin in the event of an adverse event (AE), ineligibility for further cisplatin therapy, and/or the investigator considers switching to carboplatin to be in the best interest of the participant.
Randomized dose 2 comparison cohort	vibostolimab	Participants will be randomized to receive a fixed dose (Dose 2) of vibostolimab in combination with 200 mg pembrolizumab on Day 1 of each 21-day infusion cycle until the 35-cycle limit is reached.
vibostolimab +pembrolizumab+pemetrexed+carboplatin	pembrolizumab	Participants will receive a fixed dose of vibostolimab in combination with 200 mg pembrolizumab, 500 mg/m\^2 pemetrexed, and Area Under Curve (AUC) 5 mg/mL/min carboplatin on Day 1 of each 21-day infusion cycle for up to 4 cycles followed by maintenance therapy with a fixed dose of vibostolimab in combination with 200 mg pembrolizumab and 500 mg/m\^2 pemetrexed on Day 1 of each 21-day infusion cycle for up to an additional 31 cycles.
pembrolizumab/vibostolimab coformulation China cohort	pembrolizumab/vibostolimab coformulation	Participants from mainland China will receive a fixed dose of pembrolizumab/vibostolimab coformulation, consisting of 200 mg of pembrolizumab + 200 mg vibostolimab, on Day 1 of each 21-day infusion cycle for up to 35 cycles.
Randomized dose 2 comparison cohort	pembrolizumab	Participants will be randomized to receive a fixed dose (Dose 2) of vibostolimab in combination with 200 mg pembrolizumab on Day 1 of each 21-day infusion cycle until the 35-cycle limit is reached.
vibostolimab Dose 2 Japanese cohort	vibostolimab	Japanese participants will be randomized to receive a fixed dose (Dose 2) of vibostolimab in combination with 200 mg pembrolizumab on Day 1 of each 21-day infusion cycle until the 35-cycle limit is reached.
vibostolimab+pembrolizumab+carboplatin OR cisplatin+etoposide	pembrolizumab	Participants will receive 200 mg vibostolimab in combination with 200 mg pembrolizumab, plus the investigator's choice of Area Under Curve (AUC) 5 mg/mL/min carboplatin OR 75 mg/m\^2 cisplatin on Day 1 of each 21-day cycle plus 100 mg/m\^2/day etoposide on Days 1-3 of each 21-day cycle for up to 4 cycles. Maintenance therapy with 200 mg vibostolimab in combination with 200 mg pembrolizumab on Day 1 of each 21-day cycle will continue for up to an additional 31 cycles. A participant will be allowed to switch from cisplatin to carboplatin in the event of an adverse event (AE), ineligibility for further cisplatin therapy, and/or the investigator considers switching to carboplatin to be in the best interest of the participant.
vibostolimab Dose 2 Japanese cohort	pembrolizumab	Japanese participants will be randomized to receive a fixed dose (Dose 2) of vibostolimab in combination with 200 mg pembrolizumab on Day 1 of each 21-day infusion cycle until the 35-cycle limit is reached.
pembrolizumab/vibostolimab coformulation	pembrolizumab/vibostolimab coformulation	Participants will receive a fixed dose of pembrolizumab/vibostolimab coformulation, consisting of 200 mg of pembrolizumab + 200 mg vibostolimab, on Day 1 of each 21-day infusion cycle for up to 35 cycles.
vibostolimab Dose 1 Japanese cohort	pembrolizumab	Japanese participants will be randomized to receive a fixed dose (Dose 1) of vibostolimab in combination with 200 mg pembrolizumab on Day 1 of each 21-day infusion cycle until the 35-cycle limit is reached.
vibostolimab +pembrolizumab+pemetrexed+carboplatin	pemetrexed	Participants will receive a fixed dose of vibostolimab in combination with 200 mg pembrolizumab, 500 mg/m\^2 pemetrexed, and Area Under Curve (AUC) 5 mg/mL/min carboplatin on Day 1 of each 21-day infusion cycle for up to 4 cycles followed by maintenance therapy with a fixed dose of vibostolimab in combination with 200 mg pembrolizumab and 500 mg/m\^2 pemetrexed on Day 1 of each 21-day infusion cycle for up to an additional 31 cycles.
vibostolimab +pembrolizumab+pemetrexed+carboplatin	carboplatin	Participants will receive a fixed dose of vibostolimab in combination with 200 mg pembrolizumab, 500 mg/m\^2 pemetrexed, and Area Under Curve (AUC) 5 mg/mL/min carboplatin on Day 1 of each 21-day infusion cycle for up to 4 cycles followed by maintenance therapy with a fixed dose of vibostolimab in combination with 200 mg pembrolizumab and 500 mg/m\^2 pemetrexed on Day 1 of each 21-day infusion cycle for up to an additional 31 cycles.
vibostolimab+pembrolizumab+carboplatin OR cisplatin+etoposide	carboplatin	Participants will receive 200 mg vibostolimab in combination with 200 mg pembrolizumab, plus the investigator's choice of Area Under Curve (AUC) 5 mg/mL/min carboplatin OR 75 mg/m\^2 cisplatin on Day 1 of each 21-day cycle plus 100 mg/m\^2/day etoposide on Days 1-3 of each 21-day cycle for up to 4 cycles. Maintenance therapy with 200 mg vibostolimab in combination with 200 mg pembrolizumab on Day 1 of each 21-day cycle will continue for up to an additional 31 cycles. A participant will be allowed to switch from cisplatin to carboplatin in the event of an adverse event (AE), ineligibility for further cisplatin therapy, and/or the investigator considers switching to carboplatin to be in the best interest of the participant.
vibostolimab+pembrolizumab+carboplatin OR cisplatin+etoposide	cisplatin	Participants will receive 200 mg vibostolimab in combination with 200 mg pembrolizumab, plus the investigator's choice of Area Under Curve (AUC) 5 mg/mL/min carboplatin OR 75 mg/m\^2 cisplatin on Day 1 of each 21-day cycle plus 100 mg/m\^2/day etoposide on Days 1-3 of each 21-day cycle for up to 4 cycles. Maintenance therapy with 200 mg vibostolimab in combination with 200 mg pembrolizumab on Day 1 of each 21-day cycle will continue for up to an additional 31 cycles. A participant will be allowed to switch from cisplatin to carboplatin in the event of an adverse event (AE), ineligibility for further cisplatin therapy, and/or the investigator considers switching to carboplatin to be in the best interest of the participant.
vibostolimab+pembrolizumab+carboplatin OR cisplatin+etoposide	etoposide	Participants will receive 200 mg vibostolimab in combination with 200 mg pembrolizumab, plus the investigator's choice of Area Under Curve (AUC) 5 mg/mL/min carboplatin OR 75 mg/m\^2 cisplatin on Day 1 of each 21-day cycle plus 100 mg/m\^2/day etoposide on Days 1-3 of each 21-day cycle for up to 4 cycles. Maintenance therapy with 200 mg vibostolimab in combination with 200 mg pembrolizumab on Day 1 of each 21-day cycle will continue for up to an additional 31 cycles. A participant will be allowed to switch from cisplatin to carboplatin in the event of an adverse event (AE), ineligibility for further cisplatin therapy, and/or the investigator considers switching to carboplatin to be in the best interest of the participant.

Primary Outcome Measures

Name	Time	Method
Number of Participants With Dose Limiting Toxicities (DLTs) up to 24 Months	Up to 24 Months	A DLT is defined as an event with toxicity including the type, severity, time of onset, time of resolution, and the probable association with study treatment that are not due to pre-existing conditions as defined by the Common Terminology Criteria for Adverse Events Version 4.0 (CTCAE4.0).
Number of Participants Who Experienced At Least One Adverse Event (AE)	Up to 28 Months	An AE is defined as any untoward medical occurrence in a participant or clinical investigation subject administered a pharmaceutical product and which does not necessarily have to have a causal relationship with this treatment. An adverse event can therefore be any unfavourable and unintended sign (including an abnormal laboratory finding, for example), 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 (i.e., any clinically significant adverse change in frequency and/or intensity) of a preexisting condition that is temporally associated with the use of the Sponsor's product, is also an adverse event.
Number of Participants Who Discontinued Study Treatment Due to an AE	Up to 24 Months	An AE is defined as any untoward medical occurrence in a participant or clinical investigation subject administered a pharmaceutical product and which does not necessarily have to have a causal relationship with this treatment. An adverse event can therefore be any unfavourable and unintended sign (including an abnormal laboratory finding, for example), 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 (i.e., any clinically significant adverse change in frequency and/or intensity) of a preexisting condition that is temporally associated with the use of the Sponsor's product, is also an adverse event.

Secondary Outcome Measures

Name	Time	Method
Overall Response Rate (ORR) in Participants in Vibostolimab Dose Escalation Phase Per Response Evaluation Criteria in Solid Tumors Version 1.1 (RECIST 1.1)	Up to 24 Months	ORR is the percentage of participants who experience complete response (CR: disappearance of all target lesions) or partial response (PR: at least a 30% decrease in the sum of diameters of target lesions) at any time during the trial using RECIST, version 1.1 as assessed by investigator review. Results for participants treated with vibostolimab dose escalation are presented.
ORR in Participants With Programmed Death 1 (PD-1) Refractory Non-small Cell Lung Cancer (NSCLC) Per RECIST 1.1	Up to 24 Months	ORR is the percentage of participants who experience complete response (CR: disappearance of all target lesions) or partial response (PR: at least a 30% decrease in the sum of diameters of target lesions) at any time during the trial using RECIST, version 1.1 as assessed by investigator review. Results for participants with PD-1 refractory NSCLC treated with 200 or 210 mg vibostolimab in dose escalation as well as dose expansion phases are presented.
ORR in Participants With PD-1 Naive NSCLC Per RECIST 1.1	Up to 24 Months	ORR is the percentage of participants who experience complete response (CR: disappearance of all target lesions) or partial response (PR: at least a 30% decrease in the sum of diameters of target lesions) at any time during the trial using RECIST, version 1.1 as assessed by investigator review. Results for participants with PD-1 naive NSCLC treated with pembrolizumab and 200 mg vibostolimab from both the dose escalation and expansion phases are presented.
ORR in Participants With Extensive-stage Small Cell Lung Cancer (ES-SCLC) Per RECIST 1.1	Up to 24 Months	ORR is the percentage of participants who experience complete response (CR: disappearance of all target lesions) or partial response (PR: at least a 30% decrease in the sum of diameters of target lesions) at any time during the trial using RECIST, version 1.1 as assessed by investigator review. Participants with ES-SCLC treated with vibostolimab in combination with pembrolizumab, carboplatin or cisplatin, and etoposide were analyzed.
ORR in Participants With PD-1 Naive Ovarian Cancer Per RECIST 1.1	Up to 24 Months	ORR is the percentage of participants who experience complete response (CR: disappearance of all target lesions) or partial response (PR: at least a 30% decrease in the sum of diameters of target lesions) at any time during the trial using RECIST, version 1.1 as assessed by investigator review. Participants with PD-1 naive ovarian cancer treated with pembrolizumab and vibostolimab dose escalation or MK-7984A were analyzed.
ORR in Participants With PD-1 Naive Cervical Cancer Per RECIST 1.1	Up to 24 Months	ORR is the percentage of participants who experience complete response (CR: disappearance of all target lesions) or partial response (PR: at least a 30% decrease in the sum of diameters of target lesions) at any time during the trial using RECIST, version 1.1 as assessed by investigator review. Results for participants with PD-1 naive cervical cancer treated with pembrolizumab and either 200 mg or 700 mg vibostolimab are presented.
Area Under the Curve From Time 0 to 21 Days Postdose (AUC 0-21 Days) of Plasma Vibostolimab Following Treatment With Increasing Amounts of Vibostolimab Monotherapy or Vibostolimab With 200 mg Pembrolizumab	Cycle 1, Cycle 4: Day 1 pre-dose, 0.5, and 2 hours post-dose; once daily on Days 2, 3, 5, 8, 15 and 22.	Blood samples were collected from participants during cycle 1 and cycle 4 of treatment (Cycle length is 21 days) in order to determine the AUC 0-21 days of plasma vibostolimab, Only results from participants treated with increasing amounts of vibostolimab monotherapy or vibostolimab combined with 200 mg pembrolizumab are presented; whereas other treatment groups were not analyzed. Due to terminal fitting issue, non-calculable AUC0-21 days was replaced with AUClast for a few participants.
AUC 0-21 Days of Plasma Vibostolimab Following Treatment With 200 mg Vibostolimab Combined With Various Other Treatments	Cycle 1, Cycle 4: Day 1 pre-dose, 0.5 and 2 hours post-dose; once daily on Days 2, 3, 5, 8, 15 and 22	Blood samples were collected from participants during cycle 1 and cycle 4 of treatment (Cycle length is 21 days) following treatment with 200 mg vibostolimab in order to determine the AUC 0-21 days of plasma vibostolimab, Due to terminal fitting issue, non-calculable AUC0-21 days was replaced with AUClast for a few participants.
AUC 0-21 Days of Plasma Pembrolizumab Following Treatment With Increasing Amounts of Vibostolimab With 200 mg Pembrolizumab	Cycle 1, Cycle 4: Day 1 pre-dose, 0.5 and 2 hours post-dose; once daily on Days 2, 3, 5, 8, 15 and 22	Blood samples were collected from participants during cycle 1 and cycle 4 of treatment (Cycle length is 21 days) in order to determine the AUC 0-21 days of plasma vibostolimab, Only results from participants treated with increasing amounts of vibostolimab combined with 200 mg pembrolizumab are presented; whereas other treatment groups were not analyzed. Due to terminal fitting issue, non-calculable AUC0-21 days was replaced with AUClast for a few participants.
AUC 0-21 Days of Plasma Pembrolizumab Following Treatment With 200 mg Vibostolimab and 200 mg Pembrolizumab Combined With Various Other Treatments	Cycle 1, Cycle 4: Day 1 pre-dose, 0.5 and 2 hours post-dose; once daily on Days 2, 3, 5, 8, 15 and 22	Blood samples were collected from participants during cycle 1 and cycle 4 of treatment (Cycle length is 21 days) following treatment with 200 mg vibostolimab and 200 mg pembrolizumab in order to determine the AUC 0-21 days of plasma pembrolizumab. Due to terminal fitting issue, non-calculable AUC0-21 days was replaced with AUClast for a few participants.
Maximum Plasma Concentration (Cmax) of Plasma Vibostolimab Following Treatment With Increasing Amounts of Vibostolimab Monotherapy or Vibostolimab With 200 mg Pembrolizumab	Cycle 1, Cycle 4: Day 1 pre-dose, 0.5 and 2 hours post-dose; once daily on Days 2, 3, 5, 8, 15 and 22	Blood samples were collected from participants during cycle 1 and cycle 4 of treatment (Cycle length is 21 days) in order to determine the Cmax of plasma vibostolimab, Only results from participants treated with increasing amounts of vibostolimab monotherapy or vibostolimab combined with 200 mg pembrolizumab are presented; whereas other treatment groups were not analyzed.
Cmax of Plasma Vibostolimab Following Treatment With 200 mg Vibostolimab Combined With Various Other Treatments	Cycle 1, Cycle 4: Day 1 pre-dose, 0.5 and 2 hours post-dose; once daily on Days 2, 3, 5, 8, 15 and 22	Blood samples were collected from participants during cycle 1 and cycle 4 of treatment (Cycle length is 21 days) following treatment with 200 mg vibostolimab in order to determine the Cmax of plasma vibostolimab,
Cmax of Plasma Pembrolizumab Following Treatment With Increasing Amounts of Vibostolimab With 200 mg Pembrolizumab	Cycle 1, Cycle 4: Day 1 pre-dose, 0.5 and 2 hours post-dose; once daily on Days 2, 3, 5, 8, 15 and 22	Blood samples were collected from participants during cycle 1 and cycle 4 of treatment (Cycle length is 21 days) in order to determine the Cmax of plasma vibostolimab, Only results from participants treated with increasing amounts of vibostolimab combined with 200 mg pembrolizumab are presented; whereas other treatment groups were not analyzed.
Cmax of Plasma Pembrolizumab Following Treatment With 200 mg Vibostolimab and 200 mg Pembrolizumab Combined With Various Other Treatments	Cycle 1, Cycle 4: Day 1 pre-dose, 0.5 and 2 hours post-dose; once daily on Days 2, 3, 5, 8, 15 and 22	Blood samples were collected from participants during cycle 1 and cycle 4 of treatment (Cycle length is 21 days) following treatment with 200 mg vibostolimab and 200 mg pembrolizumab in order to determine the Cmax of plasma pembrolizumab.
Trough Concentration (Ctrough) of Plasma Vibostolimab Following Treatment With Increasing Amounts of Vibostolimab Monotherapy or Vibostolimab With 200 mg Pembrolizumab	Cycle 1, Cycle 4: Day 1 pre-dose, 0.5 and 2 hours post-dose; once daily on Days 2, 3, 5, 8, 15 and 22	Blood samples were collected from participants during cycle 1 and cycle 4 of treatment (Cycle length is 21 days) in order to determine the Ctrough of plasma vibostolimab, Only results from participants treated with increasing amounts of vibostolimab monotherapy or vibostolimab combined with 200 mg pembrolizumab are presented; whereas other treatment groups were not analyzed.
Ctrough of Plasma Vibostolimab Following Treatment With 200 mg Vibostolimab Combined With Various Other Treatments	Cycle 1, Cycle 4: Day 1 pre-dose, 0.5 and 2 hours post-dose; once daily on Days 2, 3, 5, 8, 15 and 22	Blood samples were collected from participants during cycle 1 and cycle 4 of treatment (Cycle length is 21 days) following treatment with 200 mg vibostolimab in order to determine the Ctrough of plasma vibostolimab,
Ctrough of Plasma Pembrolizumab Following Treatment With Increasing Amounts of Vibostolimab With 200 mg Pembrolizumab	Cycle 1, Cycle 4: Day 1 pre-dose, 0.5 and 2 hours post-dose; once daily on Days 2, 3, 5, 8, 15 and 22	Blood samples were collected from participants during cycle 1 and cycle 4 of treatment (Cycle length is 21 days) in order to determine the Ctrough of plasma vibostolimab, Only results from participants treated with increasing amounts of vibostolimab combined with 200 mg pembrolizumab are presented; whereas other treatment groups were not analyzed.
Ctrough of Plasma Pembrolizumab Following Treatment With 200 mg Vibostolimab and 200 mg Pembrolizumab Combined With Various Other Treatments	Cycle 1, Cycle 4: Day 1 pre-dose, 0.5 and 2 hours post-dose; once daily on Days 2, 3, 5, 8, 15 and 22	Blood samples were collected from participants during cycle 1 and cycle 4 of treatment (Cycle length is 21 days) following treatment with 200 mg vibostolimab and 200 mg pembrolizumab in order to determine the Ctrough of plasma pembrolizumab.
Half Life (t1/2)) of Plasma Vibostolimab Following Treatment With Increasing Amounts of Vibostolimab Monotherapy or Vibostolimab With 200 mg Pembrolizumab	Cycle 1, Cycle 4: Day 1 pre-dose, 0.5 and 2 hours post-dose; once daily on Days 2, 3, 5, 8, 15 and 22	Blood samples were collected from participants during cycle 1 and cycle 4 of treatment (Cycle length is 21 days) in order to determine the t1/2 of plasma vibostolimab, Only results from participants treated with increasing amounts of vibostolimab monotherapy or vibostolimab combined with 200 mg pembrolizumab are presented; whereas other treatment groups were not analyzed.
t1/2 of Plasma Vibostolimab Following Treatment With 200 mg Vibostolimab Combined With Various Other Treatments	Cycle 1, Cycle 4: Day 1 pre-dose, 0.5 and 2 hours post-dose; once daily on Days 2, 3, 5, 8, 15 and 22	Blood samples were collected from participants during cycle 1 and cycle 4 of treatment (Cycle length is 21 days) following treatment with 200 mg vibostolimab in order to determine thet1/2 of plasma vibostolimab,
t1/2 of Plasma Pembrolizumab Following Treatment With Increasing Amounts of Vibostolimab With 200 mg Pembrolizumab	Cycle 1, Cycle 4: Day 1 pre-dose, 0.5 and 2 hours post-dose; once daily on Days 2, 3, 5, 8, 15 and 22	Blood samples were collected from participants during cycle 1 and cycle 4 of treatment (Cycle length is 21 days) in order to determine the t1/2 of plasma vibostolimab, Only results from participants treated with increasing amounts of vibostolimab combined with 200 mg pembrolizumab are presented; whereas other treatment groups were not analyzed.
t1/2 of Plasma Pembrolizumab Following Treatment With 200 mg Vibostolimab and 200 mg Pembrolizumab Combined With Various Other Treatments	Cycle 1, Cycle 4: Day 1 pre-dose, 0.5 and 2 hours post-dose; once daily on Days 2, 3, 5, 8, 15 and 22	Blood samples were collected from participants during cycle 1 and cycle 4 of treatment (Cycle length is 21 days) following treatment with 200 mg vibostolimab and 200 mg pembrolizumab in order to determine the t1/2 of plasma pembrolizumab.
Number of Participants Experiencing a Dose-Limiting Toxicity (DLT) at the End of Cycle 1	At the end of Cycle 1 (up to 21 days)	A DLT is defined as an event with toxicity including the type, severity, time of onset, time of resolution, and the probable association with study treatment that are not due to pre-existing conditions as defined by CTCAE 4.0
Rate of Progression Free Survival (PFS) Per RECIST 1.1 at 6 Months	6 months	The progression free survival (PFS) rate is the percentage of participants who achieve PFS as estimated by the Kaplan-Meier method. PFS is the time from randomization to the first documented progressive disease (PD) or death due to any cause, whichever occurs first using RECIST, version 1.1 as assessed by investigator review. PD is defined as ≥20% increase in the sum of diameters of target lesions. In addition to the relative increase of 20%, the sum must also demonstrate an absolute increase of ≥5 mm. The appearance of one or more new lesions is also considered PD. Rate of PFS was planned and therefore only reported for participants treated with vibostolimab in combination with pembrolizumab, carboplatin or cisplatin, and etoposide. Other treatment groups were not analyzed.