Crystallographic Survey of Albumin Drug Interaction and Preliminary Applications in Cancer Chemotherapy

An overview of the results of a comprehensive crystallographic structural survey of drug binding to human albumin at atomic resolution is presented. More than 350 complexes were examined, ultimately producing more than 200 structures with representatives in every major therapeutic category. The survey indicated 12 independent drug-binding locations dominated by the three sites located within subdomains IIA, IIIA, and IB. Site IB, the most structurally accommodating site on albumin, revealed a propensity for large heterocyclic ligands and showed the highest overall binding frequency at 49%. Details of IB ligand-binding chemistry are presented for several ligands including the camptothecin, anthracyclin, and podophylotoxin families of oncology drugs. The results from the survey were used to establish a therapeutic drug combination approach that favorably alters the albumin-based pharmacokinetics of several highly cytotoxic oncology drugs leading to marked improvements in safety and efficacy. Examples are presented for selected applications of improving the albumin-based pharmacokinetics of this information in drug development to improving the safety and efficacy of highly cytotoxic drugs for several important families of oncology drugs. Keywords: crystallography; drug binding; oncology; serum albumin; survey