Table 1.

Linker Chemistries of the ADCs Approved for Clinical Use

ADC	Linker Chemistry	Year approved
Enzyme cleavable
Brentuximab vedotin (Adcetris)	carbamate, dipeptide, thioether	2011
Polatuzumab vedotin (Polivy)	carbamate, dipeptide, thioether	2019
Enfortumab vedotin (Padcev)	carbamate, dipeptide, thioether	2019
Trastuzumab deruxtecan (Enhertu)	amide, tripeptide, thioether	2019
Trastuzumab emtansine (Kadcyla)	thioether, amide	2013
Enzyme or acid cleavable/ Reducible disulfide
Gemtuzumab ozogamicin (Mylotarg)	disulfide, hydrazone, amide	2000*
Inotuzumab ozogamicin (Besponza)	disulfide, hydrazone, amide	2017
Acid cleavable
Sacituzumab govitecan (Trodelvy)	carbonate, triazole, thioether	2020

^*It was taken off market in 2010 and reapproved in 2017