Disclosed is the use of a synergistic combination of: an antibody specific for CD19 and fludarabine, for the manufacture of a medicament for the treatment of non-Hodgkin&rsquos lymphoma, chronic lymphocytic leukaemia and/or acute lymphoblastic leukaemia, wherein the antibody comprises an HCDR1 region of sequence SYVMH (SEQ ID NO: 1), an HCDR2 region of sequence NPYNDG (SEQ ID NO: 2), an HCDR3 region of sequence GTYYYGTRVFDY (SEQ ID NO: 3), an LCDR1 region of sequence RSSKSLQNVNGNTYLY (SEQ ID NO: 4), an LCDR2 region of sequence RMSNLNS (SEQ ID NO: 5), and an LCDR3 region of sequence MQHLEYPIT (SEQ ID NO: 6).
