Virtual Bioequivalence Assessment of Ritlecitinib Capsules with Incorporation of Observed Clinical Variability Using a Physiologically Based Pharmacokinetic Model
January 2024
in “
The AAPS Journal
”
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Studysummary This study demonstrates that bioequivalence for proposed 50-mg ritlecitinib capsules versus clinical 100-mg capsules can be supported using a PBPK model-based biowaiver, achieving over 90% probability of success. Our plain-language summary of this paper — not a Tressless recommendation.
The study developed and applied a physiologically based pharmacokinetic (PBPK) model to assess the bioequivalence of ritlecitinib capsules, a treatment for alopecia areata. Despite slower in vitro dissolution of 100-mg capsules compared to proposed 50-mg capsules, virtual bioequivalence (VBE) trials incorporating clinically observed intra-subject variability (ICV) demonstrated that the 50-mg capsules are bioequivalent to the 100-mg capsules with over 90% probability of success. This suggests a PBPK model-based biowaiver for clinical bioequivalence studies, offering a novel approach to integrate clinical ICV into VBE trials.
