A Study of Ibrutinib (PCI-32765) in Chinese Participants With Relapse or Refractory Waldenstrom's Macroglobulinemia (WM)

Inclusion Criteria: * Men and women greater than or equal to (\>=) 18 years of age * Eastern Cooperative Oncology Group (ECOG) less than or equal to (\<=) 2 * Previously received at least one prior therapy for WM and have had either documented disease progression or had no response to the most recent treatment regimen * Centrally confirmed clinicopathological diagnosis of WM * Measurable disease defined as serum monoclonal immunoglobulin M (IgM) \>0.5 gram per deciliter (g/dL) * Symptomatic disease, requiring treatment * Hematology and biochemical values within protocol-defined limits * Female participants of childbearing potential must have a negative serum pregnancy test at screening and agree to use highly effective methods of contraception while taking study drug. Female participants of childbearing potential should avoid becoming pregnant while taking ibrutinib and for up to 1 month after the last dose of study drug. Male participants must use an effective barrier method of contraception during the study and for 3 months following the last dose of ibrutinib if sexually active with a female of childbearing potential Exclusion Criteria: * Involvement of the central nervous system by WM * Evidence of disease transformation * Prior exposure to BTK inhibitors * Known hypersensitivity reaction to ibrutinib or to the excipients in its formulation * Received any WM-related therapy \<=30 days prior to first administration of study treatment * Received a prior allogeneic hemato…