{Reference Type}: Journal Article
{Title}: Fusion to a highly stable consensus albumin binding domain allows for tunable pharmacokinetics.
{Author}: Jacobs SA;Gibbs AC;Conk M;Yi F;Maguire D;Kane C;O'Neil KT;
{Journal}: Protein Eng Des Sel
{Volume}: 28
{Issue}: 10
{Year}: Oct 2015
{Factor}: 1.952
{DOI}: 10.1093/protein/gzv040
{Abstract}: A number of classes of proteins have been engineered for high stability using consensus sequence design methods. Here we describe the engineering of a novel albumin binding domain (ABD) three-helix bundle protein. The resulting engineered ABD molecule, called ABDCon, is expressed at high levels in the soluble fraction of Escherichia coli and is highly stable, with a melting temperature of 81.5°C. ABDCon binds human, monkey and mouse serum albumins with affinity as high as 61 pM. The solution structure of ABDCon is consistent with the three-helix bundle design and epitope mapping studies enabled a precise definition of the albumin binding interface. Fusion of a 10 kDa scaffold protein to ABDCon results in a long terminal half-life of 60 h in mice and 182 h in cynomolgus monkeys. To explore the link between albumin affinity and in vivo exposure, mutations were designed at the albumin binding interface of ABDCon yielding variants that span an 11 000-fold range in affinity. The PK properties of five such variants were determined in mice in order to demonstrate the tunable nature of serum half-life, exposure and clearance with variations in albumin binding affinity.