A Study to Investigate Safety of INT2104 Infusions in Participants Aged 18 Years of Age and Older Who Have B-cell Cancers That Came Back After Previous Treatment

Inclusion Criteria: * Diagnosed with relapsed/refractory (R/R) B-NHL (Burkitt's lymphoma are eligible for Part B only) confirmed by histology or flow cytometry Note: Bone Marrow involvement is allowed * B-NHL must have CD20 antigen positive tumour confirmed from a tumour biopsy taken at screening * Measurable disease at the time of enrolment * Progression after at least 2 lines of systemic therapy * Has not received more than one prior marketed CAR-T cell therapy (including tandem or bispecific CAR-T) or other genetically modified T-cell therapy. * Sex and Contraceptive/Barrier Requirements consistent with local regulations for clinical trials Females: must have negative serum pregnancy test at screening and on Day -1 prior to INT2104 infusion Both sexes: must agree to use highly effective methods, including a barrier method after INT2104 infusion * Haematological criteria: * Absolute lymphocyte count (ALC) ≥300/µL * Platelet count ≥50,000/mL * Absolute neutrophil count (ANC) ≥500/µL * Eastern Cooperative Oncology Group (ECOG) score of 0 or 1 * Adequate renal, cardiac, hepatic, and lung function Key Inclusion Part B only * Diagnosed with relapsed/refractory B-ALL, and with exceptions as detailed in exclusion criteria. Participants with Philadelphia chromosome positive (Ph+) B-ALL disease are eligible. * B-ALL participants must have CD20 antigen positive leukaemia * Measurable disease at the time of enrolment * Participants with Burkitt's lymphoma are eligible for Pa…