Please select the eligibility criteria that correspond to the clinical trial below.
Title: A Phase Ib Multi-Cohort Study of MK-3475 in Subjects With Advanced Solid Tumors
Brief Summary: This study is being done to investigate the safety, tolerability and anti-tumor activity of pembrolizumab (MK-3475) in participants with advanced triple negative breast cancer (TNBC) (Cohort A), advanced head and neck cancer (Cohorts B and B2), advanced urothelial cancer (Cohort C), or advanced gastric cancer (Cohort D). Additionally, for Cohort D, data is presented for Asian Pacific (AP) participants. Only participants with programmed cell death-ligand 1 (PD-L1) expressing tumors were enrolled in Cohorts A, B, C and D. Participants in Cohort B2 were enrolled irrespective of PD-L1 status.

The primary study hypothesis is that pembrolizumab is safe and well-tolerated.


Options:
A: Inclusion Criteria:

* Histologically or cytologically-confirmed diagnosis of tumor that is recurrent, metastatic, or persistent:

  * For Cohort A - triple negative breast cancer (estrogen, progesterone, and human epidermal growth factor receptor 2 \[HER2\] negative)
  * For Cohort B - squamous cell carcinoma of the head and neck (including human papilloma virus (HPV)-positive head and neck squamous cell cancer).
  * For Cohort C - urothelial tract cancer of the renal pelvis, ureter, bladder, or urethra (transitional cell or non-transitional cell histology)
  * For Cohort D - adenocarcinoma of the stomach or gastroesophageal junction
  * For Cohort B2 - squamous cell carcinoma of the head and neck (both HPV-positive and -negative head and neck squamous cell cancer)
* Any number of prior treatment regimens
* Measurable disease
* Eastern Cooperative Oncology Group (ECOG) Performance status of 0 or 1
* Female participants of childbearing potential must be willing to use 2 methods of birth control or be surgically sterile, or abstain from heterosexual activity for the course of the study through 120 days after the last dose of study treatment
* Male participants must agree to use an adequate method of contraception starting with the first dose of study therapy through 120 days after the last dose of study treatment

Exclusion Criteria:

* Currently participating in/has participated in a study of an investigational agent or using an investigational device within 4 weeks of the first dose of study treatment
* Diagnosis of immunosuppression or receiving systemic steroid therapy or any other form of immunosuppressive therapy within 7 days prior to the first dose of study treatment
* Anti-cancer monoclonal antibody treatment within 4 weeks prior to study Day 1 or not recovered from adverse events due to agents administered more than 4 weeks earlier
* Chemotherapy, targeted small molecule therapy or radiation therapy within 2 weeks prior to study Day 1 or not recovered from adverse events due to a previously administered agent
* Known additional malignancy that is progressing or requires active treatment excepting basal cell carcinoma of the skin, squamous cell carcinoma of the skin, or in situ cervical cancer that has undergone potentially curative therapy
* Known active central nervous system (CNS) metastases and/or carcinomatous meningitis
* Active autoimmune disease requiring systemic treatment within the past 3 months or documented history of clinically severe autoimmune disease, or syndrome that requires systemic steroids or immunosuppressive agents
* Evidence of interstitial lung disease
* Active infection requiring systemic therapy
* Known psychiatric or substance abuse disorders
* Pregnant, breastfeeding, or expecting to conceive or father children within the projected duration of the trial, starting with the pre-screening or screening visit through 120 days after the last dose of trial treatment
* Prior therapy with an anti-programmed cell death 1 (PD-1), anti-PD-L1, anti-PD-L2, anti-CD137 antibody, or anti-cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4) antibody
* Known history of human immunodeficiency virus (HIV)
* Known active Hepatitis B or Hepatitis C
* Received live vaccine within 30 days prior to start of study treatment
* Is or has an immediate family member (e.g., spouse, parent/legal guardian, sibling or child) who is Investigational site or Sponsor staff directly involved with this trial, unless prospective Independent Review Board (IRB) approval (by Chair or Designee) is given allowing exception to this criterion for a specific participant
B: Inclusion Criteria:

* Age 18 or older.
* In the dose-escalation phase: histologically- or cytologically- confirmed advanced solid tumor that is refractory to standard therapy and for which no standard therapy exists.
* In the dose-expansion phase: histologically- or cytologically- confirmed advanced solid tumor where if an approved first-line therapy is available, participants must have failed, be intolerant to, be ineligible for, or have refused
* Eastern Cooperative Oncology Group (ECOG) status of 0 or 1.
* Adequate organ and marrow function.
* Participants must have at least 1 measurable lesion.
* Available archived tumor tissue sample.
* Willingness to provide consent for biopsy sample (dose-expansion only)

Exclusion Criteria:

* Any prior Grade ≥ 3 immune-mediated adverse event (imAE) while receiving immunotherapy
* Prior exposure to any anti-PD-1 or anti-PD-L1 antibody
* Any concurrent chemotherapy, immunotherapy, biologic or hormonal therapy for cancer treatment.
* Prior treatment with immunotherapy agents including, but not limited to, tumor necrosis factor receptor superfamily agonists or checkpoint inhibitors or natural killer (NK) cell inhibitors.
* Active or prior documented autoimmune disease within the past 2 years
* History of primary immunodeficiency
* History of organ transplant that requires use of immunosuppressives
* Symptomatic or untreated central nervous system (CNS) metastases requiring concurrent treatment
* Other invasive malignancy within 2 years
* Women who are pregnant or lactating
* Uncontrolled intercurrent illness
* Known history of tuberculosis
* Known to be human immunodeficiency virus (HIV) positive
* Known to be Hepatitis B or C positive (except HCC participants)
C: Inclusion Criteria:

* Histologically or cytologically documented locally advanced or metastatic transitional cell carcinoma of the urothelium (including renal pelvis, ureters, urinary bladder, urethra)
* Representative tumor specimens as specified by the protocol
* Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1
* Life expectancy greater than or equal to (\>=) 12 weeks
* Measurable disease, as defined by RECIST v1.1
* Adequate hematologic and end organ function

Cohort 2-Specific Inclusion Criteria

* Disease progression during or following treatment with at least one platinum-containing regimen (e.g., gemcitabine and cisplatin \[GC\], methotrexate, vinblastine, doxorubicin, and cisplatin \[MVAC\], CarboGem, etc.) for inoperable locally advanced or metastatic urothelial carcinoma or disease recurrence.
* A regimen was defined as participants receiving at least two cycles of a platinum-containing regimen. Participants who had received one cycle of a platinum-containing regimen but discontinued due to Grade 4 hematologic toxicity or Grade 3 or 4 non-hematologic toxicity could also be eligible.
* Participants who received prior adjuvant/neoadjuvant chemotherapy and progressed within 12 months of treatment with a platinum-containing adjuvant/neoadjuvant regimen were considered as second-line participants.

Exclusion Criteria:

* Any approved anti-cancer therapy within 3 weeks prior to initiation of study treatment
* Treatment with any other investigational agent or participation in another clinical trial with therapeutic intent within 28 days prior to enrollment
* Active or untreated central nervous system (CNS) metastases as determined by computed tomography (CT) or magnetic resonance imaging (MRI) evaluation during screening and prior radiographic assessments
* Leptomeningeal disease
* Uncontrolled tumor-related pain
* Uncontrolled pleural effusion, pericardial effusion, or ascites requiring recurrent drainage procedures (once monthly or more frequently)
* Uncontrolled hypercalcemia (greater than \[\>\] 1.5 millimoles per liter \[mmol/L\] ionized calcium or Ca \> 12 milligrams per deciliter \[mg/dL\] or corrected serum calcium \> upper limits of normal \[ULN\]) or symptomatic hypercalcemia requiring continued use of bisphosphonate therapy or denosumab
* Malignancies other than urothelial bladder cancer within 5 years prior to Cycle 1, Day 1, with the exception of those with a negligible risk of metastasis or death treated with expected curative outcome or incidental prostate cancer
* Pregnant and lactating women
* History of autoimmune disease
* History of idiopathic pulmonary fibrosis, organizing pneumonia, drug-induced pneumonitis, idiopathic pneumonitis, or evidence of active pneumonitis on screening chest CT scan
* Serum albumin less than (\<) 2.5 grams per deciliter (g/dL)
* Positive test for human immunodeficiency virus (HIV) and/or active hepatitis B or hepatitis C or tuberculosis
* Severe infections within 4 weeks prior to Cycle 1, Day 1
* Significant cardiovascular disease
* Major surgical procedure other than for diagnosis within 28 days prior to Cycle 1, Day 1
* Prior allogeneic stem cell or solid organ transplant
* Administration of a live, attenuated vaccine within 4 weeks before Cycle 1, Day 1
* Any other diseases, metabolic dysfunction, physical examination finding, or clinical laboratory finding giving reasonable suspicion of a disease or condition that contraindicates the use of an investigational drug or that may affect the interpretation of the results or render the patient at high risk from treatment complications
* Prior treatment with CD137 agonists or immune checkpoint blockade therapies, including anti-cytotoxic T lymphocyte-associated antigen 4 (anti-CTLA-4), anti-programmed death-1 receptor (anti-PD-1), and anti-programmed death-ligand 1 (anti-PD-L1) therapeutic antibodies
D: Inclusion Criteria

* Considered to be eligible to receive platinum-based chemotherapy, in the investigator's judgment
* Eastern Cooperative Oncology Group (ECOG) performance status of less than or equal to (\</=) 2
* Histologically documented, locally advanced (T4b, any N; or any T, N2-3) or metastatic urothelial carcinoma (mUC) (M1, Stage IV) (also termed transitional cell carcinoma \[TCC\] or urothelial cell carcinoma \[UCC\] of the urinary tract; including renal pelvis, ureters, urinary bladder, and urethra)
* Representative formalin-fixed paraffin-embedded (FFPE) tumor specimens in paraffin blocks (blocks preferred) or at least 15 unstained slides, with an associated pathology report, for central testing and determined to be evaluable for tumor PD-L1 expression prior to study enrollment; participants who have fewer than 15 unstained slides available at baseline (but no less than \[\<\] 10) may be eligible following discussion with the Medical Monitor
* No prior chemotherapy for inoperable locally advanced or mUC
* For participants who received prior adjuvant/neoadjuvant chemotherapy or chemo-radiation for urothelial carcinoma, a treatment-free interval more than (\>) 12 months between the last treatment administration and the date of recurrence is required in order to be considered treatment naive in the metastatic setting
* Prior local intravesical chemotherapy or immunotherapy is allowed if completed at least 4 weeks prior to the initiation of study treatment
* Measurable disease, as defined by RECIST v1.1
* Adequate hematologic and end-organ function
* For women of childbearing potential: agreement to remain abstinent (refrain from heterosexual intercourse) or use contraceptive methods that result in a failure rate of \<1% per year during the treatment period and for at least 6 months after the last dose of carboplatin, cisplatin, or gemcitabine or for 5 months after the last dose of atezolizumab
* For men: agreement to remain abstinent (refrain from heterosexual intercourse) or use contraceptive measures and agreement to refrain from donating sperm

Exclusion Criteria:

* Any approved anti-cancer therapy, including chemotherapy or hormonal therapy, within 3 weeks prior to initiation of study treatment
* Treatment with any other investigational agent or participation in another clinical study with therapeutic intent within 28 days prior to enrolment
* Active or untreated CNS metastases as determined by computed tomography (CT) or magnetic resonance imaging evaluation during screening and prior radiographic assessments
* Participants with treated asymptomatic central nervous system (CNS) metastases are eligible, provided they meet all of the following criteria: \* Evaluable or measurable disease outside the CNS \* No metastases to midbrain, pons, medulla, or within 10 mm of the optic apparatus (optic nerves and chiasm) \* No history of intracranial or spinal cord hemorrhage \* No ongoing requirement for corticosteroid as therapy for CNS disease; anti-convulsants at a stable dose are allowed \* No evidence of significant vasogenic edema \* No stereotactic radiation, whole-brain radiation or neurosurgical resection within 4 weeks prior to Cycle 1, Day 1 \* Radiographic demonstration of interim stability (i.e., no progression) between the completion of CNS-directed therapy and the screening radiographic study \* Screening CNS radiographic study \>/=4 weeks since completion of radiotherapy or surgical resection and \>/=2 weeks since discontinuation of corticosteroids
* Prior treatment with CD137 agonists, anti-CTLA-4, anti-programmed death-1 (PD-1), or anti-PD-L1 therapeutic antibody or pathway-targeting agents
* Treatment with systemic corticosteroids or other systemic immunosuppressive medications (including but not limited to prednisone, dexamethasone, cyclophosphamide, azathioprine, methotrexate, thalidomide, and anti-tumor necrosis factor \[TNF\] agents) within 2 weeks prior to Cycle 1, Day 1 or anticipated requirement for systemic immunosuppressive medications during the study
* Leptomeningeal disease
* Uncontrolled pleural effusion, pericardial effusion, or ascites requiring recurrent drainage procedures (once monthly or more frequently)
* Uncontrolled tumour-related pain or hypercalcemia
* Significant cardiovascular disease including known left ventricular ejection fraction (LVEF) \<40%
* Severe infections within 4 weeks before randomization or therapeutic oral or IV antibiotics within 2 weeks before randomization
* Major surgical procedure within 4 weeks prior to randomization or anticipation of need for a major surgical procedure during the course of the study other than for diagnosis
* Malignancies other than urothelial carcinoma within 5 years prior to Cycle 1, Day 1
* Life expectancy of \<12 weeks
* Pregnant or lactating, or intending to become pregnant during the study
* Serum albumin \<25 gram per liter (g/L)
* History of severe allergic, anaphylactic, or other hypersensitivity reactions to chimeric or humanized antibodies or fusion proteins
* Known hypersensitivity or allergy to biopharmaceuticals produced in Chinese hamster ovary cells or any component of the atezolizumab formulation
* History of autoimmune disease
* Participants with prior allogeneic stem cell or solid organ transplantation
* History of idiopathic pulmonary fibrosis (including pneumonitis), drug-induced pneumonitis, organizing pneumonia (i.e., bronchiolitis obliterans, cryptogenic organizing pneumonia), or evidence of active pneumonitis on screening chest CT scan
* Positive test for human immunodeficiency virus (HIV)
* Active hepatitis B or hepatitis C
* Active tuberculosis
* Administration of a live, attenuated vaccine within 4 weeks before Cycle 1, Day 1

Answer: A