Prediction of Human Pharmacokinetics Profile of Monoclonal Antibody Using hFcRn Transgenic Mouse Model

A Quantitative Prediction Method for the Human Pharmacokinetics of Fc-Fusion Proteins

BACKGROUND AND OBJECTIVE

Fc fusion is an effective strategy for extending the half-lives of therapeutic proteins. This study aimed to evaluate the applicability of a human pharmacokinetics prediction method for Fc-fusion proteins by extending on reported methods for monoclonal antibodies (mAbs).

METHODS

To predict human pharmacokinetic profiles following intravenous (IV) dosing, the pharmacokinetic data for 11 Fc-fusion proteins in monkeys were analysed by two approaches: a species-invariant time method with a range of allometric exponents in clearance (CL, 0.7-1.0) and a two-compartment model reported for mAbs. The pharmacokinetic profiles following subcutaneous (SC) dosing were predicted by simple dose normalisation from monkeys or using the geometric means of the absorption rate constant (Ka) and bioavailability (BA) for mAbs or Fc-fusion proteins in humans and compared.

RESULTS

In the case of IV administration, the area under the curve could be predicted for more than 85% of Fc-fusion proteins within a twofold difference from the observed value using the species-invariant time method (scaling exponent for CL, 0.95). For SC dosing, incorporating the geometric means of absorption parameters for both mAbs (BA 68.2%, Ka 0.287 day-1) and Fc-fusion proteins (BA 63.0%, Ka 0.209 day-1) in humans provided better accuracy than simple normalisation from monkeys.

CONCLUSION

We have successfully predicted the human pharmacokinetic profiles of Fc-fusion proteins for both IV and SC administration within twofold of the observed value from monkey pharmacokinetic data by extending on reported methods for mAbs. This method will facilitate drug discovery and development of Fc-fusion proteins.

Discovery and characterization of prolactin neutralizing monoclonal antibodies for the treatment of female-prevalent pain disorders

Prolactin (PRL) has recently been demonstrated to elicit female-selective nociceptor sensitization and increase pain-like behaviors in female animals. Here we report the discovery and characterization of first-in-class, humanized PRL neutralizing monoclonal antibodies (PRL mAbs). We obtained two potent and selective PRL mAbs, PL 200,031 and PL 200,039. PL 200,031 was engineered as human IgG1 whereas PL 200,039 was reformatted as human IgG4. Both mAbs have sub-nanomolar affinity for human PRL (hPRL) and produce concentration-dependent and complete inhibition of hPRL signaling at the hPRL receptor (hPRLR). These two PRL mAbs are selective for hPRL as they do not inhibit other hPRLR agonists such as human growth hormone or placental lactogen. They also cross-react with non-human primate PRL but not with rodent PRL. Further, both mAbs show long clearance half-lives after intravenous administration in FcRn-humanized mice. Consistent with their isotypes, these mAbs only differ in binding affinities to Fcγ receptors, as expected by design. Finally, PL 200,019, the murine parental mAb of PL 200,031 and PL 200,039, fully blocked stress-induced and PRL-dependent pain behaviors in female PRL-humanized mice, thereby providing in vivo preclinical proof-of-efficacy for PRL mAbs in mechanisms relevant to pain in females.

Review of the Existing Translational Pharmacokinetics Modeling Approaches Specific to Monoclonal Antibodies (mAbs) to Support the First-In-Human (FIH) Dose Selection

The interest in therapeutic monoclonal antibodies (mAbs) has continuously growing in several diseases. However, their pharmacokinetics (PK) is complex due to their target-mediated drug disposition (TMDD) profiles which can induce a non-linear PK. This point is particularly challenging during the pre-clinical and translational development of a new mAb. This article reviews and describes the existing PK modeling approaches used to translate the mAbs PK from animal to human for intravenous (IV) and subcutaneous (SC) administration routes. Several approaches are presented, from the most empirical models to full physiologically based pharmacokinetic (PBPK) models, with a focus on the population PK methods (compartmental and minimal PBPK models). They include the translational approaches for the linear part of the PK and the TMDD mechanism of mAbs. The objective of this article is to provide an up-to-date overview and future perspectives of the translational PK approaches for mAbs during a model-informed drug development (MIDD), since the field of PK modeling has gained recently significant interest for guiding mAbs drug development.