Abstract: The present disclosure relates to a multi-specific antibody molecule comprising or consisting of: a) a polypeptide chain of formula (I): VH-CH1-CH2-CH3-X-(V1)p; and b) a polypeptide chain of formula (II): VL-CL-Y-(V2)q and pharmaceutical formulations comprising, for example for use in treatment. The disclosure also provides polynucleotide sequences encoding said multi-specific antibody molecules, vectors comprising the polynucleotides and host cells comprising said vectors and/or polynucleotide sequences. There is a provided a method of expressing a multi-specific antibody molecule of the present disclosure from a host cell.