The present invention relates to a method (dosage regimen) for administering a CD3×CD20 bispecific antibody to a human patient, comprising (a) administering a first dose of said antibody in a specific dosage； and consecutively (b) administering a second dose of said antibody after a period of time, wherein said second dose exceeds said first dose. The methods of the invention (and likewise the dosage regimen of the invention) are also suitable for treating B cell (CD20-positive) cancer in a human patient, or for ameliorating and/or preventing a medical condition mediated by the periodic or continued administration of a CD3×CD20 bispecific antibody to a human patient. The present invention also relates to the use of a CD3×CD20 bispecific antibody for the preparation of a pharmaceutical composition to be used in a method or treatment regime as defined in any one of the preceding claims. A pharmaceutical package or kit comprising the first dose, the second dose, and any subsequent doses are also part of the present invention.
