The present invention relates to uses of bispecific antibodies exhibiting cross-species specificity for evaluating the in vivo safety and/or activity and/or pharmacokinetic profile of the same in non-human species and humans. The present invention moreover relates to methods for evaluating the in vivo safety and/or activity and/or pharmacokinetic profile of said bispecific antibodies exhibiting cross-species specificity. The present invention also relates to methods of measuring the biological activity and/or efficacy of such bispecific antibodies exhibiting cross-species specificity. In addition, the present invention relates to pharmaceutical compositions comprising bispecific single chain antibodies exhibiting cross-species specificity and to methods for the preparation of pharmaceutical compositions comprising said bispecific single chain antibodies exhibiting cross-species specificity for the treatment of diseases.
