Alternative antibody formats.

During the past two decades, numerous recombinant antibody formats have been designed and produced by genetic engineering, extending and improving the activities of naturally occurring antibodies. However, while whole IgG molecules, antibody fragments and chemically modified derivatives thereof are being used clinically, alternative antibody formats still await regulatory approval. This review summarizes recent progress in the development of alternative antibody formats for therapeutic applications, with an emphasis on molecules that are in clinical testing.