To Assess the Safety and Tolerability of Tafasitamab Alone or in Combination With Other Drugs in Japanese Participants With Non-Hodgkins Lymphoma (NHL)

Inclusion criteria

• Group 1 only: Biopsy-proven participants with relapsed or refractory NHL of DLBCL, FL or MZL.
• Groups 3, 4a and 5 only: Biopsy-proven participants with relapsed or refractory DLBCL.
• Groups 2 and 6 only: Biopsy-proven participants with DLBCL and another select lymphoid neoplasms.
• Participants must have at least 1 bi-dimensionally measurable lesion.
• ECOG performance status of 0 to 2.
• Participants with protocol defined laboratory criteria at screening as defined in the protocol.
• Group 1 only:

Received at least 1 previous systemic therapy line for the treatment of NHL. At least 1 previous therapy line must have included a CD20-targeted therapy (eg, RTX).

• Groups 2, 3, 4a and 6 only:

Received at least 1, but no more than 3, previous systemic therapy lines for the treatment of DLBCL. At least 1 previous therapy line must have included a CD20-targeted therapy (eg, RTX).

• Group 5 only: Participants must have:

• Untreated DLBCL.
• Ann Arbor Stage III to IV.
• IPI status of 3 to 5 or age-adjusted IPI 2-3 (in Group 5 only).
• Appropriate candidate for R-CHOP.
• LVEF of ≥ 50%, assessed by echocardiography.
• Willingness to avoid pregnancy or fathering children.
• In the opinion of investigator, the participant must:

• Not have a history of noncompliance in relation to medical regimens or be considered potentially unreliable and/or uncooperative.
• Be able to understand the reason for complying with the special conditions of the pregnancy prevention risk management plan and give written acknowledgement of this.

Exclusion criteria

• Any other histological type of lymphoma.
• History of prior non-hematologic malignancy.
• Congestive heart failure requiring use of ongoing maintenance therapy for life-threatening ventricular arrhythmias.
• Participants with known positive test result for hepatitis C, and hepatitis B.
• Known seropositive for or history of active viral infection with HIV.
• Known active bacterial, viral, fungal, mycobacterial, or other infection at screening.
• Known CNS lymphoma involvement - present or past medical history.
• History or evidence of clinically significant cardiovascular, CNS and/or other systemic disease that would in the investigator's opinion preclude participation in the study or compromise the participant's ability to give informed consent.
• History or evidence of rare hereditary problems of galactose intolerance, Lapp lactase deficiency or glucose-galactose malabsorption.
• History or evidence of interstitial lung disease.
• Vaccination with live vaccine within 21 days prior to study treatment (Note: throughout the study treatment period and at least 6 months after end of treatment, vaccination with live vaccines should be avoided).
• Major surgery within up to 30 days prior to signing the ICF, unless the participant is recovered at the time of signing the ICF.
• Any anticancer and/or investigational therapy within 14 days prior to the start of Cycle 1.
• Groups 2, 3, 4a, 5 and 6 only: Gastrointestinal abnormalities including the inability to take oral study treatment, requiring IV alimentation, or prior surgical procedure affecting absorption.
• Pregnancy or lactation.
• Groups 2, 3, 5 and 6 only: Participants who have history of deep venous thrombosis/embolism, threatening thromboembolism, stroke or known thrombophilia or are at a high risk for a thromboembolic event in the opinion of the investigator and who are not willing/able to take venous thromboembolic event prophylaxis during the entire treatment period if required
• Group 4a only: Use or expected use during the study of any restricted medications, including potent CYP3A4 inhibitors or inducers within 14 days or 5 half-lives (whichever is longer) before the date of study treatment administration
• Groups 1, 3, 4a and 6 only: Participants who have:

• Not discontinued CD20-targeted therapy, chemotherapy, radiotherapy, investigational anticancer therapy, or other lymphoma-specific therapy within the 14 days prior to Day 1 dosing.
• In the opinion of the investigator, not recovered sufficiently from the adverse toxic effects of prior therapies.
• Groups 1, 3 and 4a only: Previous treatment with CD19-targeted therapy (eg, CD19-CAR-T therapies, other CD19 mAbs including bispecific and ADCs).

Groups 2 and 6 only: Previous treatment with tafasitamab. Note: Participants in Groups 2 and 6 who have received previous CD19 directed therapy (other than tafasitamab) must have CD19-positive lymphoma confirmed by a biopsy taken after completing the prior CD19-targeted therapy.

• Groups 2, 3 and 6 only: Been previously treated with IMiDs (eg, thalidomide or LEN).
• Group 4a only: Been previously treated with selective PI3Kδ or pan-PI3K inhibitors (eg, idelalisib, copanlisib, duvelisib) and/or Bruton's tyrosine kinase inhibitors (eg, ibrutinib).
• A history of hypersensitivity to compounds of similar biological or chemical composition to tafasitamab, IMiDs, and/or the excipients contained in the study treatment formulations (citric acid monohydrate, polysorbate 20, sodium citrate dehydrate and trehalose dihydrate).
• Undergone ASCT within the period ≤ 3 months before the signing of the ICF. Participants who have a more distant history of ASCT must exhibit full hematological recovery before enrolment into the study.
• Undergone previous allogenic stem cell transplantation.
• Concurrent treatment other anticancer or experimental treatments.
• Group 5 only: Participants who have:

• A history of radiation therapy to ≥ 25% of the bone marrow for other diseases or history of anthracycline therapy.
• A history of hypersensitivity or contraindication to any component of R-CHOP, LEN, or compounds of similar biological or chemical composition as tafasitamab and/or the excipients contained in the study treatment formulations or R-CHOP.
• Contraindication to any of the individual components of R-CHOP.
• Any anticancer and/or investigational therapy within 30 days prior to the start of Cycle 1, except for permitted prephase treatment defined below.