A Nanotechnology-Based Platform for Extending the Pharmacokinetic and Binding Properties of Anti-methamphetamine Antibody Fragments

Abstract

To address the need for effective medications to aid in the treatment of methamphetamine (METH) abuse, we used a nanotechnology approach to customize the in vivo behavior of an anti-METH single chain antibody (scFv7F9Cys). Anti-METH scFv7F9Cys was conjugated to dendrimer nanoparticles via a polyethylene glycol (PEG) linker to generate high-order conjugates termed dendribodies. We found that the high affinity (KD = 6.2 nM) and specificity for METH was unchanged after nanoparticle conjugation. The dendribodies were administered in an i.v. bolus to male Sprague Dawley rats after starting a s.c. infusion of METH. The PCKN values for clearance and volume of distribution of scFv7F9Cys after conjugation to dendrimers decreased 45 and 1.6-fold respectively, and the terminal elimination half-life increased 20-fold. Organ distribution of scFv7F9Cys and dendribody in blood and urine agreed well with the PCKN data. Renal clearance appeared to be the major route of elimination for both experimental medications. We have thus successfully developed a novel multivalent METH-binding nanomedicine by conjugating multiple anti-METH scFvs to dendrimer nanoparticles, extending the scFv half-life from 1.3 (±0.3) to 26 (±2.6) hr. These data suggest that the dendribody design could be a feasible platform for generating multivalent antibodies with customizable PCKN profiles.

PEGylation of a High-Affinity Anti-(+)Methamphetamine Single Chain Antibody Fragment Extends Functional Half-Life by Reducing Clearance

“…However, these studies either did not administer any drug to remove METH from the brain (53), or administered an NMDA antagonist that may elicit off-target effects (52). Additionally, we do not believe that scFv7F9Cys or scFv7F9Cys-PEG have a direct effect in the brain, as a previous biodistribution study from this lab showed that scFv7F9Cys was not detected in brain tissue (54). Therefore, scFv7F9Cys and the PEG20K conjugate likely elicit a rapid removal of METH from the brain without direct effects at other neurological receptors, differing in mechanism from previous studies, and possibly eliciting a new result of reduced TH concentrations.…”

The Development and Characterization of an scFv-Fc Fusion–Based Gene Therapy to Reduce the Psychostimulant Effects of Methamphetamine Abuse

“…In contrast, we have previously reported the design and testing of a single chain variable fragment (scFv7F9), which consists of the variable regions of an IgG connected by a 15 amino acid linker (Hay et al, 2018). ScFv7F9 binds with high affinity to METH (KD = 6.2 nM) and to the active metabolite amphetamine, with lower affinity (IC50 = 8 µM) (Nanaware-Kharade et al, 2015). The short half-life of scFvs, which is approximately 60 min due to high clearance rate, limits the circulating concentrations of anti-METH antibodies in mice.…”

Biologics to treat substance use disorders: Current status and new directions

“…To improve mAb half-life, a nanotechnologybased approach generated anti-methamphetamine mAb conjugated to dendrimers, known as dendribodies, which showed proof of pre-clinical efficacy. 151 Antigen-specific mAb can also be directly isolated from B cells of vaccinated subjects. Using various strategies, antigen-specific B cells are isolated from PBMC by cell sorting and their BCR is sequenced, cloned, and expressed in mammalian cell systems to produce antigenspecific mAb.…”