Profile: Concortis Biosystems, Corp. is a biotechnology company creating next generation biotherapeutics using our proprietary conjugation technologies and novel drug delivery systems. Our platforms include ADC, carriers and PEGylation. We also provide customized design and synthesis of generic linkers. We offer toxins such as kinase inhibitors, HDAC inhibitors, proteasome inhibitors, self-destruct compounds and androgen and estrogen antagonist. Our generic linkers include prodrug linkers and bifunctional linkers. Prodrug linkers are designed to release cytotoxic payloads at the tumor site while are stable in blood stream. One of the most commonly used is peptide-based linkage that can be cleaved by intracellular lysosome enzymes such as cathepsin B. The other one is disulfide-bond-based linkage that can be cleaved in the reducing environment of tumor. Bifunctional linkers are designed to connect targeting mAB and payloads using two different chemistries, such as amide or carbamate bond formation, oxime formation, thiol chemistry and click chemistry.