The following criteria is provided for health care professionals.

Inclusion Criteria:

• Confirmed diagnosis of relapsed/refractory multiple myeloma
• Measurable disease
• Failed at least 2 lines of prior therapy (e.g. bortezomib or carfilzomib and either thalidomide, pomalidomide, or lenalidomide)
• Archival and/or newly obtained bone marrow aspirate/biopsy material available
• Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1
• Adequate organ function
• Must agree to follow the regional requirements for lenalidomide counseling, pregnancy testing, and birth control; willing and able to comply with the regional requirements (for example, periodic pregnancy tests and safety labs)
• Male participants must agree to use a latex condom during sexual contact with females of childbearing potential even if they have had a successful vasectomy starting with the first dose of study therapy through 120 days after the last dose of study therapy
• Able to swallow capsules and able to take or tolerate oral medications on a continuous basis

Exclusion Criteria:

• Currently participating in or has participated in a study of an investigational agent or using an investigational device within 4 weeks of the first dose of treatment
• History of repeated infections, primary amyloidosis, hyperviscosity, plasma cell leukemia; polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, and skin changes (POEMS) syndrome, Waldenström's macroglobulinemia or immunoglobulin M (IgM) myeloma
• Diagnosis of immunosuppressive disorder or on any other immunosuppressive therapy within 7 days prior to the first dose of trial treatment
• Monoclonal antibody therapy within 4 weeks prior to study Day 1 or not recovered from adverse events due to agents administered more than 4 weeks earlier
• Prior chemotherapy (including dexamethasone), 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
• An additional malignancy within the last 5 years
• Clinically active central nervous system (CNS) involvement
• Active autoimmune disease or a documented history of autoimmune disease, or a syndrome that requires systemic steroids or immunosuppressive agents
• Evidence of active, non-infectious pneumonitis
• Active infection requiring intravenous systemic therapy
• Known psychiatric or substance abuse disorders that would interfere with cooperation with the requirements of the trial
• Pregnant or 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 (PD)-1, anti-PD-L1, anti-PD-L2, anti-CD137 antibody, or anti-Cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4) agent
• Human Immunodeficiency Virus (HIV), Hepatitis B (HBV), or Hepatitis C (HCV)
• Clinically significant coagulopathy
• Known symptomatic congestive heart failure, unstable angina pectoris, or cardiac arrhythmia
• Allogeneic stem cell transplant
• Autologous stem cell transplant within 12 weeks before the first infusion
• Has received bortezomib, carfilzomib, pomalidomide or thalidomide within 2 weeks before the first infusion
• History of Grade 4 rash associated with thalidomide treatment
• Known hypersensitivity to thalidomide or pomalidomide
• Eligible for or planning for allogeneic hematopoietic stem cell transplant
• Known gastrointestinal disease that may significantly alter the absorption of lenalidomide
• Unable or unwilling to undergo antithrombotic prophylactic treatment
• Received a live vaccine within 30 days of planned start of trial therapy
• Is or has immediate family member (spouse or children) who is a member of the investigational site or sponsor staff directly involved with this trial, unless prospective Institutional Review Board (IRB) approval (by Chair or Designee) is given allowing exception to this criterion