Looking to exploit antibody generation processes unique to a rabbit's immune system, Apexigen Inc. is developing humanized mAbs that it believes will have best-in-class potential by offering better affinity and specificity than humanized murine antibodies. Rabbit mAbs also recognize a greater number of epitopes, which may make it possible to generate mAbs against antigens that have been impossible to target with other types of antibodies.

Earlier this year, the company spun out of service play Epitomics Inc., which had developed a pair of technologies to generate and humanize rabbit-derived mAbs. Apexigen took an exclusive license to the technologies to develop mAbs for therapeutic applications, and has access to Epitomics' antibody generation and screening infrastructure. The parent retained rights to the technologies for diagnostic, research services and reagent purposes.