Designed ankyrin repeat proteins (DARPins) offer several distinct advantages over conventional monoclonal antibodies as therapeutic agents and research tools. They are significantly smaller in size, which allows for superior tissue penetration and higher accumulation in solid tumors. DARPins exhibit exceptional thermal and chemical stability, meaning they do not easily aggregate and can be manufactured efficiently in high yields using simple microbial fermentation processes rather than costly mammalian cell cultures. Furthermore, their modular structure enables them to be easily engineered into multi-specific or multivalent formats, simultaneously targeting multiple disease pathways or viral epitopes with high affinity.