DS-3201b in Participants With Lymphomas

Inclusion Criteria:

Has hematocytological or pathological diagnosis of non- Hodgkin's lymphoma (NHL)
Has relapsed from or is refractory to standard treatment or no standard treatment is available
Is the age of majority in their country (18 in the US and 20 in Japan) at the time of informed consent
Has Eastern Cooperative Oncology Group (ECOG) performance status 0 or 1
Has at least one evaluable lesion site (not applicable for the DDI cohort)
Has preserved organ function based on baseline laboratory data at screening tests
If of reproductive potential, agrees to avoid harvesting ova or sperm, and to use a protocol-defined form of contraception or avoid intercourse, during and upon completion of the study, and for at least 3 months after the last dose of study drug

Tumor biopsy collections:

willing to provide archived or fresh tumor tissue samples that are sufficient for comprehensive genomic and/or proteomic analyses at baseline

[US only] willing to provide fresh on-treatment tumor biopsy if deemed acceptable risk by the investigator

[Japan only] fresh on-treatment tumor biopsy should be performed if deemed acceptable risk by the investigator

willing to provide optional fresh end-of-treatment biopsy

For ATL subjects:

Has a positive test result for human T-lymphotropic virus type I antibody
Has ATL subtype classified as acute, lymphomatous, or chronic with poor prognostic factor
Has diagnosis of relapse (including relapse after partial remission [PR]) or treatment-resistant ATL at the time of informed consent after prior treatment with at least 1 anti-cancer medication regimen

Exclusion Criteria:

Has been diagnosed with protocol-defined cutaneous T-cell lymphoma or T-cell leukemia. For DDI cohort, CTCL is not exclusionary.
Has a history or presence of central nervous system (CNS) involvement
Has a medical history, complication or other malignancy considered inappropriate for participation in the study, or a serious physical or psychiatric disease, the risk of which may be increased by participation in the study
Has received drugs or other treatments not allowed by the protocol
History of treatment with other enhancer of zeste (EZH) inhibitors
Has had allogeneic hematopoietic stem cell transplantation (HTCP) within 90 days before scheduled dosing on Cycle 1 Day 1
Is pregnant or breastfeeding
Is otherwise deemed ineligible to participate by the investigator or sub-investigator

DDI Cohort Only:

Has received following medications within 14 days prior to study drug administration
Any CYP3A inhibitors/inducers including weak CYP3A inhibitors/inducers, and P-gp inhibitors, midazolam as well as digoxin