ReachBio Research Labs is now offering off-target toxicity and linker stability assay services for antibody drug conjugates (ADCs).  
 
ReachBio has developed two distinct assay platforms to assess cytotoxicity caused by ADCs.  The first platform evaluates off-target toxicity using colony-forming cell (CFC) assays to assess effects on erythroid, myeloid or megakaryocyte progenitors using bone marrow derived from human, NHP, rat and mouse.  
 
The second platform focuses on the stability of various linker constructs.  ReachBio adapted the neutrophil differentiation assay whereby neutrophils cause their own demise by releasing enzymes which cleave the payload from the antibody and thus kill developing neutrophils.  Using primitive human bone marrow CD34+ cells and specialized cytokine formulations, ReachBio can induce neutrophil development in vitro.  
 
Dr. Emer Clarke, Chief Scientific Officer at ReachBio, said, “As more complex biological drug structures emerge, we see a subsequent rise in new challenges such as off-target toxicity which may be in part be related to the structure. We have clients that are looking for assays that can ‘rank’ a series of such compounds in terms of toxicity. We also have clients that are interested in these new assay platforms to see if they correlate with their in vivo toxicity models, and therefore provide an alternate ‘rapid and less expensive’ way to assess either efficacy or toxicity.”