The invention concerns the use of human or humanized chimeric monoclonal antibodies which are produced in selected cell lines, said antibodies bringing about a high ADCC activity as well as a high secretion of cytokines and interleukins, for treating underpopulations of so-called weak-response patients exhibiting CD16 FCGR3A-158F homozygote or FCGR3A-158V/F heterozygote polymorphism.