Predicting Drug Exposure During Pregnancy Using PBPK Models
Pregnancy is associated with numerous physiologic changes that can influence absorption, distribution, metabolism and excretion of medications. Moreover, the magnitude of these changes differs over the course of the pregnancy. For most medications, limited information is available about changes in drug disposition that can occur in pregnancy, yet most pregnant women are prescribed one or more medications. Accordingly, determining a safe and effective dose is challenging due to a lack of clinical studies involving pregnant women. Recent evidence suggests that physiologically based pharmacokinetic (PBPK) modeling is a potentially useful tool to characterize the pharmacokinetic profile of a medication in special populations such as pregnancy.
In this webinar, Dr. David Taft, Professor at Long Island University’s School of Pharmacy, described how the Simcyp pregnancy-PBPK model was used to predict systemic exposure during pregnancy for two probe medications: tacrolimus and oseltamivir. These medications represent compounds with different ADME properties. Model simulations were compared to clinical data in pregnant subjects in different trimesters of pregnancy as well as post-partum women. Dr. Taft also showed how the Simcyp Simulator can be used to correlate alterations in systemic exposure (Cmax, AUC) with various pregnancy-associated changes including organ blood flow, enzyme and transporter activity, and plasma protein levels. Finally, he discussed the future extensions of this research.