Physiochemical and Biochemical Factors Influencing the Pharmacokinetics of Antibody Therapeutics

Abstract

Abstract. Monoclonal antibodies are increasingly being developed to treat multiple disease areas, including those related to oncology, immunology, neurology, and ophthalmology. There are multiple factors, such as charge, size, neonatal Fc receptor (FcRn) binding affinity, target affinity and biology, immunoglobulin G (IgG) subclass, degree and type of glycosylation, injection route, and injection site, that could affect the pharmacokinetics (PK) of these large macromolecular therapeutics, which in turn could have ramifications on their efficacy and safety. This minireview examines how characteristics of the antibodies could be altered to change their PK profiles. For example, it was observed that a net charge modification of at least a 1-unit shift in isoelectric point altered antibody clearance. Antibodies with enhanced affinity for FcRn at pH 6.0 display longer serum half-lives and slower clearances than wild type. Antibody fragments have different clearance rates and tissue distribution profiles than full length antibodies. Fc glycosylation is perceived to have a minimal effect on PK while that of terminal high mannose remains unclear. More investigation is warranted to determine if injection route and/or site impacts PK. Nonetheless, a better understanding of the effects of all these variations may allow for the better design of antibody therapeutics.

Tailoring recombinant protein quality by rational media design

“…The efficacy, potency and safety depend on the structural characteristics of the protein entity 11 , which explains the particular attention paid in biotherapeutic development to post-translational modifications that the expressed protein may undergo 1,12,14,[39][40][41] . In the particular case of monoclonal antibodies (mAbs), increased antibody-dependent cell-mediated cytotoxicity (ADCC) is one of the major objectives to increase the immune response of the human body and thus clinical efficacy 42 .…”

“…In the particular case of monoclonal antibodies (mAbs), increased antibody-dependent cell-mediated cytotoxicity (ADCC) is one of the major objectives to increase the immune response of the human body and thus clinical efficacy 42 . Many studies have addressed various effects of glycosylation and charge variants on the biological activity and pharmacokinetics 11,40,43,44 . On that account, it is of utmost importance to understand the glycosylation process and how it is influenced by cell culture variations in bioprocess development and manufacturing in order to manage to control and optimize the glycan pattern 24 .…”

“…In these biotherapeutic molecules, N-glycans are linked to the two conserved asparagine residues (Asn 297) in the CH2 domain of the Fc region 61 . A large number of reports describe various impacts of glycosylation on the quality attributes of biologics including in vivo efficacy [62][63][64] , pharmacokinetics (PK) 11 , antibody-dependent cellular cytotoxicity (ADCC) 63,65 and complementdependent cytotoxicity (CDC) activities 66 , stability and overall structure of the molecule 63 , clearance and half-life in vivo 10 as well as immunogenicity 10,67 . Non-fucosylated therapeutic antibodies exhibit 50 to 1,000-fold higher efficacy than their fucosylated counterparts 65 due, in most cases, to enhanced ADCC activity 68 .…”

“…The neutralized samples from day 3 to 7 were concentrated, using Vivaspin 500 30,000 MWCO pore size (Sartorius Stedim, Göttingen, Germany). Both the concentrated (days 3-7) and the non-concentrated neutralized eluates (days [8][9][10][11][12][13][14] were denatured by indole-3-acetic acid in 0.6 M denaturation reagent (GlykoPrep-plus, Europa Bioproducts, Cambridge, UK) and reduced. Following purification, the samples were labelled with 2-amino-benzamide and then dried for 3 days.…”

“…Ensuing the patent expiry of best-selling biological molecules many companies have pursued biosimilar development, and thus, tools to modulate the quality attributes of recombinant proteins have gained much interest from early process development stages on 10 . The structural characteristics of recombinant therapeutic proteins including a variety of complex post-translational modifications have a direct link with their safety and inherent biological activity in vivo [11][12][13] . Within the array of these modifications, glycosylation most strongly affects pharmacokinetics and protein physiochemical properties 14 .…”