title: Protein-polyanion interactions for the controlled release of monoclonal antibodies.
abstract: The objective of the present study was to investigate ionic interactions between alginate and a monoclonal antibody (mAb1) and to utilize those interactions for the sustained release of mAb1. The existence of ionic interactions between alginate and mAb1 was strongly reflected by their rheological behavior. A 3-4 times increase in storage modulus (G') was observed by addition of 30 mg/mL mAb1 to a 20 mg/mL alginate solution. This increase was strongly dependent on pH and ionic strength. In vitro release studies revealed a marked pH-dependence of release rates and the reversibility of alginate-mAb1 complexation under physiological conditions. Two alginate-mAb1 sustained release formulations were developed by an internal gelation technique using CaCO(3) and CaHPO(4) as calcium sources for physical cross-linking. The CaCO(3) formulation provided a stable pH-environment, optimally suited for pH-sensitive proteins. CaHPO(4) led to a lower pH and stronger alginate-mAb1 interactions. The CaHPO(4) cross-linked alginate released mAb1 over a period of 10-15 days. The long release period and changes in viscoelastic properties of alginate, when being mixed with mAb1, indicate the incorporation of mAb1 molecules into a mixed network with alginate. The results of this study demonstrate that ionic interactions between polyanions and mAb1 are present and that they can be exploited for sustained release delivery of mAb1.
authors.affiliation: Biologics Process R&D, Technical R&D, Novartis Pharma AG, Basel, Switzerland.
authors.forename: Daniel
authors.initials: D
authors.lastname: Schweizer
authors.forename: Karin
authors.initials: K
authors.lastname: Schönhammer
authors.forename: Michael
authors.initials: M
authors.lastname: Jahn
authors.forename: Achim
authors.initials: A
authors.lastname: Göpferich
mesh_terms: D000911:Antibodies, Monoclonal / Q000008:administration & dosage / Q000737:chemistry / Q000378:metabolism*; D003692:Delayed-Action Preparations / Q000008:administration & dosage / Q000737:chemistry / Q000378:metabolism*; D006801:Humans; D000071228:Polyelectrolytes; D011108:Polymers / Q000008:administration & dosage / Q000737:chemistry / Q000378:metabolism*; D011485:Protein Binding / Q000502:physiology; D011994:Recombinant Proteins / Q000008:administration & dosage / Q000737:chemistry / Q000378:metabolism*; D012212:Rheology / Q000379:methods
chemical_list: D000911:Antibodies, Monoclonal; D003692:Delayed-Action Preparations; D000071228:Polyelectrolytes; D011108:Polymers; D011994:Recombinant Proteins