An Albumin Sandwich Enhances in Vivo Circulation and Stability of Metabolically Labile Peptides

Bioconjug Chem. 2019 Jun 19;30(6):1711-1723. doi: 10.1021/acs.bioconjchem.9b00258. Epub 2019 Jun 6.

Abstract

The effectiveness of numerous molecular drugs is hampered by their poor pharmacokinetics. Different from previous approaches with limited effectiveness, most recently, emerging high-affinity albumin binding moieties (ABMs) for in vivo hitchhiking of endogenous albumin opens up an avenue to chaperone small molecules for long-acting therapeutics. Although several FDA-approved fatty acids have shown prolonged residence and therapeutic effect, an easily synthesized, water-soluble, and high-efficiency ABM with versatile drug loading ability is urgently needed to improve the therapeutic efficacy of short-lived constructs. We herein identified an ideal bivalent Evans blue derivative, denoted as N(tEB)2, as a smart ABM-delivery platform to chaperone short-lived molecules, through both computational modeling screening and efficient synthetic schemes. The optimal N(tEB)2 could reversibly link two molecules of albumin through its two binding heads with a preferable spacer, resulting in significantly extended circulation half-life of a preloaded cargo and water-soluble. Notably, this in situ dimerization of albumin was able to sandwich peptide therapeutics to protect them from proteolysis. As an application, we conjugated N(tEB)2 with exendin-4 for long-acting glucose control in a diabetic mouse model, and it was superior to both previously tested NtEB-exendin-4 (Abextide) and the newly FDA-approved semaglutide, which has been arguably the best commercial weekly formula so far. Hence, this novel albumin binder has excellent clinical potential for next-generation biomimetic drug delivery systems.

Publication types

  • Research Support, N.I.H., Intramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Binding Sites
  • Cell Line, Tumor
  • Evans Blue / analogs & derivatives*
  • Evans Blue / chemical synthesis
  • Evans Blue / metabolism*
  • Exenatide / analogs & derivatives*
  • Exenatide / blood
  • Exenatide / chemical synthesis
  • Exenatide / metabolism*
  • Humans
  • Hypoglycemic Agents / blood
  • Hypoglycemic Agents / chemical synthesis
  • Hypoglycemic Agents / chemistry
  • Hypoglycemic Agents / metabolism
  • Mice
  • Models, Molecular
  • Pharmaceutical Preparations / blood
  • Pharmaceutical Preparations / chemical synthesis
  • Pharmaceutical Preparations / chemistry
  • Pharmaceutical Preparations / metabolism
  • Protein Binding
  • Protein Multimerization
  • Proteolysis
  • Rats
  • Serum Albumin / chemistry
  • Serum Albumin / metabolism*

Substances

  • Hypoglycemic Agents
  • Pharmaceutical Preparations
  • Serum Albumin
  • Evans Blue
  • Exenatide