FCGRT and neoplasm: The conjugates equipped with the cleavable [VC(S)] linker had potent antitumor activity in vivo facilitatedby the release of free MMAE upon FcRn binding and internalization.In addition to the pronounced antitumor activity of the albumin conjugates in vivo, we also demonstrated their preferable tumor biodistributionand biocompatibility with no associated toxicity or side effects.These results suggest that the use of engineered albumins with highFcRn binding combined with protease cleavable linkers is an efficientstrategy to target delivery of drugs to solid tumors.