The data presented here provide experimental evidence that BIIB015 is a potent targeted therapeutic molecule to directly kill Cripto positive tumour cells….BIIB015 specifically kills Cripto positive cells, in vitro and in vivo….In this experiment, mice bearing subcutaneous CT-3 colon tumour xenografts were treated with 20 mg/kg BIIB015 with or without a three-fold excess of naked huB3F6 (60 mg/kg). Treatment with BIIB015 alone inhibited tumour growth by 75–80%.