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Modeling Delayed Outcomes in PK Studies Using Delay Differential Equations

20161214
On-Demand Webinar
YouTube video

Delays are ubiquitous in the pharmacokinetics (PK) and pharmacodynamics (PD) studies. Transit compartment models, described by systems of ordinary differential equations, have been widely used to describe delayed outcomes in PK and PD studies. The obvious disadvantage for this type of model is it requires manually finding proper values for the number of compartments. In addition, it may require many differential equations to fit the data and may not adequately describe some complex features.

Delay differential equations (DDEs) provide an alternative way to model delayed outcomes that does not suffer these disadvantages. In this webinar, we will introduce DDEs and demonstrate their relationship with traditional models such as transit compartment models, typical absorption models, and models for describing atypical absorption profiles. We will also explain how DDEs are implemented in Phoenix NLME and demonstrate this new functionality with some examples.

About Our Speakers

Webinar-3speaker-Dunlavey-Guzy-HuDr. Michael Dunlavey is a software developer with decades of experience in consulting, teaching, and tool development. He has been with Certara since 1998, participating in developing Trial Simulator 2, Phoenix Modeling Language, Phoenix NLME, and many other products. He has published several papers on software development and a book, “Building Better Applications: A Theory of Efficient Software Development”, ISBN 0-442-01740-5.

Serge Guzy, PhD, is currently a Pharmacometrics Professor Affiliate at the University of Maryland, Adjunct Professor at the University of Minnesota, Adjunct Professor at the University of Colorado, Adjunct Professor at UC Denver, President and CEO of POP_PHARM, a and Senior Consultant at Certara. Serge is the co-developer of the MCPEM algorithm, a popular algorithm that has been expanded into the QRPEM algorithm, a robust algorithm implemented in Phoenix for population analysis. Serge has written two book chapters on Pharmacometrics and more than 30 peer reviewed papers.

Dr. Shuhua Hu is a senior research scientist in the scientific group at Certara. Before she joined Certara, she had worked at North Carolina State University for ten years with a research focus on mathematical modeling, simulation, estimation, optimal control, and uncertainty propagation and quantification in the area of biomedicine and engineering. She has published over thirty peer-review journal publications and a book “Modeling and Inverse Problems in the Presence of Uncertainty”.

Delays are ubiquitous in the pharmacokinetics (PK) and pharmacodynamics (PD) studies. Transit compartment models, described by systems of ordinary differential equations, have been widely used to describe delayed outcomes in PK and PD studies. The obvious disadvantage for this type of model is it requires manually finding proper values for the number of compartments. In addition, it may require many differential equations to fit the data and may not adequately describe some complex features.

Delay differential equations (DDEs) provide an alternative way to model delayed outcomes that does not suffer these disadvantages. In this webinar, we introduced DDEs and demonstrated their relationship with traditional models such as transit compartment models, typical absorption models, and models for describing atypical absorption profiles. We also explained how DDEs are implemented in Phoenix NLME and demonstrated this new functionality with some examples.