Abstract 4905: Utility of human FcRn transgenic mice for preclinical screening of immunotherapeutics

Preclinical assessment is required for the growing number of immunotherapeutics in development. Clinically relevant pharmacokinetic analysis can be achieved by using transgenic mice that uniquely express the human Fc receptor neonatal (hFcRn). To demonstrate the utility of the human FcRn Tg mouse model platform, three immunotherapeutics (pembrolizumab, ipilimumab, and belatacept) were administered IV to Tg32, Tg276, FcRn null, and B6 wild type mice. The mice were blood sampled (25 µL) at 1, 3, 5, 7, 9, 12, 16, 19, 22, 26, and 30 days. Immunotherapeutic plasma concentations, assessed by human IgG ELISA, were pharmacokinetically analyzed. Tg32 mice yielded half-life values for these immunotherapeutics with ranges that mimicked patient data. Though reduced in scale, Tg276 mice also produced half-life data that correlated with the established human half-life data for pembrolizumab, ipilimumab, and belatacept. These results confirm that the human FcRn Tg model platform can be broadly applied to preclinical pharmacokinetic screening of mAb and Fc-fusion based immunotherapeutics. Citation Format: Gregory J. Christianson, Emily Lowell, Cat Lutz. Utility of human FcRn transgenic mice for preclinical screening of immunotherapeutics [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 4905.