Clinical Pharmacology Podcast with Nathan Teuscher

Today’s episode is a discussion of renal and hepatic impairment. I review the biology of the kidney and liver and how we analyze pharmacokinetic data to assess their impact on drug exposure. Links discussed in the show:You can connect with me on LinkedIn and send me a message Send me a message Sign up for my newsletter Copyright Teuscher Solutions LLCAll Rights Reserved

Today’s episode is about allometric scaling with therapeutic antibodies. I discuss differences from small molecules, how to handle antibodies with engineered Fc regions (e.g. YTE or LS), and using allometry to extrapolate from adults to pediatrics for these antibodies. Links discussed in the show:Haray and Tachibana’s article on allometric exponents for monoclonal antibodies Exponents for standard antibodies: CL = 0.8, Q = 0.75, Vc = 1/.0, Vp = 0.95Exponents for modified antibodies: CL = 0.55, Q = 6, Vc = 0.95, Vp = 0.95You can connect with me on LinkedIn and send me a message Send me a message Sign up for my newsletter Copyright Teuscher Solutions LLCAll Rights Reserved

In this episode I discuss bioequivalence testing and how it was developed to support generic drug approvals, but is now a mainstream tool for all of drug development. I discuss the basics of what bioequivalence means, how the studies are designed, and then how to perform the statistical analysis. I end with some examples of how this can be used for both generic drug and innovator drugs to support labeling. Links discussed in the show:FDA Draft Guidance: Statistical Approaches to Establishing Bioequivalence (Dec 2022) – Excellent detail on methods, models, and SAS examples. FDA Guidance: Bioequivalence Studies with Pharmacokinetic Endpoints for Drugs Submitted Under an ANDA. Article: “Bioequivalence of generic drugs: a simple explanation for clinicians” (Andrade, 2015) – Great for the 80-125% intuition. R-script with example BE analysis (Be sure to copy this text into a file and name it "BE-example.R" then you can run it on your local R instance.You can connect with Nathan on LinkedIn and send me a message Send Nathan a message Sign up for Nathan’s newsletter Copyright Teuscher Solutions LLCAll Rights Reserved

In this episode we’re going to define Volume of Distribution, look at the different types of Volume of Distribution parameters, talk about how we actually calculate it, examine what drives its value, and—most importantly—discuss why it matters for the decisions we make every day in drug development. Links discussed in the show:Volume of Distribution Volume of Distribution in Drug Design You can connect with Nathan on LinkedIn and send me a message Send Nathan a message Sign up for Nathan’s newsletter Copyright Teuscher Solutions LLCAll Rights Reserved

This episode is an interview with Michael Stackhouse, the Chief Innovation Officer at Atorus Research. We discussed a variety of topics such as modern data science tools, why regulatory agencies want to get rid of SAS transport files in favor of Dataset JSON file formats, and how AI is being used in data programming and data science. Links discussed in the show:Connect with Mike on LinkedIn Learn more about Atorus Research on their websiteYou can connect with Nathan on ⁠LinkedIn and send me a message⁠⁠Send Nathan a message⁠⁠Sign up for Nathan’s newsletter⁠Copyright Teuscher Solutions LLCAll Rights Reserved

This episode is an interview with Dr. Wouter Vaes, the Chief Science Officer of Peregrion. We discuss how accelerator mass spectrometry is being used in early clinical development for drug metabolism and pharmacokinetics. We discuss using this technology to support development of oncology agents, determining absolute bioavailability without IV toxicology work, and more. Links discussed in the show:You can contact Wouter by email: [email protected] Connect with Peregrion on LinkedIn or their websiteSymposium on microtracer studies FDA guidance on safety testing of drug metabolitesWhite paper on human ADME data You can connect with Nathan on LinkedIn and send me a message Send Nathan a message Sign up for Nathan’s newsletter Copyright Teuscher Solutions LLCAll Rights Reserved

This episode is an interview with Aruna Dhontabhaktuni, Founder and CEO of RegKey, a regulatory intelligence platform that uses AI. The discussion touches on how companies can leverage large language model AI tools to accelerate regulatory strategy work.Links discussed in the show:You can contact Aruna by email: [email protected] the RegKey website Connect with Aruna on LinkedIn You can connect with Nathan on LinkedIn and send me a message Send Nathan a message Sign up for Nathan’s newsletter Copyright Teuscher Solutions LLC

This episode is a collection of my thoughts on model-informed drug development and where different modeling modalities fit into the development schedule. These are just my opinions and each development program is different.Links discussed in the show:You can connect with me on LinkedIn and send me a message Send me a message Sign up for my newsletter Copyright Teuscher Solutions LLCAll Rights Reserved

In this episode I chat with Ahmed Elmokadem about QSP modeling. Ahmed, from Metrum Research Group, is an expert consultant in QSP modeling and how it can be used to provide a framework to connect mechanistic understanding with clinical pharmacology and decision-making.Links discussed in the show:Connect with Ahmed on LinkedIn on on his websiteAhmed’s book: Numbers that Dazzled the World You can connect with me on ⁠LinkedIn and send me a message⁠⁠Send me a message⁠⁠Sign up for my newsletter⁠

In this episode I discuss dataset-JSON, a new proposed data standard for CDISC files and explain some of the CDISC files I use in my clinical pharmacology work. I end with some brief thoughts about the ACoP 2025 meeting in Denver in October 2025.Links discussed in the show:CDISC dataset-JSON CDISC files I use You can connect with me on LinkedIn and send me a message Send me a message Sign up for my newsletter Copyright Teuscher Solutions LLCAll Rights Reserved

In this episode I discuss review statistics that are commonly used in pharmacokinetics and pharmacometrics work. I reviewed the basic theory of the normal distribution and then discussed various individual statistics that we use in PK work. I concluded with some examples of which statistics I use in my work. Links discussed in the show:Link to message about harmonic mean You can connect with me on LinkedIn and send me a message Send me a message Sign up for my newsletter Copyright Teuscher Solutions LLCAll Rights Reserved

In this episode I discuss clinical trial simulations. I review concepts of trial simulation including different variability terms and when to use them. I also share my thoughts on 3 different applications used in clinical trial simulation. Links discussed in the show:Trial Simulator Software page Simulx Software page You can connect with me on LinkedIn and send me a message Send me a message Sign up for my newsletter Copyright Teuscher Solutions LLCAll Rights Reserved

In this episode I discuss R Shiny and how it can be used for building clinical pharmacology tools. I provide an overview of the technology, suggest a few example use cases, and then walk through a specific practical example of predicting AUC and Cmax for future doses from observed data. I end with a discussion of the benefits and challenges of using R Shiny for clinical pharmacology tools. Links discussed in the show:Basics about R ShinyShinyapps.io for hosting shiny apps Example R Shiny app by Samer Mouskassi: ggplot with your dataExample R Shiny app for AUC-Cmax predictions You can connect with me on LinkedIn and send me a message Send me a message Sign up for my newsletter Copyright Teuscher Solutions LLCAll Rights Reserved

In this episode I discuss noncompartmental analysis. I categorize PK parameters calculated by NCA methods as either Important, Useful, or Questionable. I also share my thoughts on how to report PK parameters calculated using NCA methods in nonclinical and clinical reports. I want to hear your thoughts about this episode. Do you agree or disagree with my categorization of PK parameters? Why? Use the links below to let me know.Links discussed in the show:You can connect with me on LinkedIn and send me a message Send me a message Sign up for my newsletter Copyright Teuscher Solutions LLCAll Rights Reserved

In this episode I review the process I follow for fitting a base pharmacokinetic (PK) model. I talk from the perspective of an individual PK model, but include some differences associated with population PK models. I go over exploratory data analysis, getting initial estimates, and how to choose between different base models.Links discussed in the show:AIC and BICYou can connect with me on LinkedIn and send me a message Send me a message Sign up for my newsletter Copyright Teuscher Solutions LLCAll Rights Reserved

In this episode I discuss different algorithms used for pharmacometrics modeling. I describe difference between maximum likelihood and expectation maximization methods. I review the FO and FOCEI maximum likelihood algorithms. I then review SAEM, IMP, and QRPEM expectation maximization algorithms that are available. I conclude with an brief explanation of the difference between parameter estimation and parameter uncertainty. Links discussed in the show:PMXRepoJames Ousey LinkedIn pageManuscript by Liu and Wang, 2016You can connect with me on LinkedIn and send me a messageSend me a messageSign up for my newsletterCopyright Teuscher Solutions LLCAll Rights Reserved

In this episode I discuss my experience as an independent consultant in the clinical pharmacology and pharmacometrics space. I talk about how I got from high school to become a consultant. I touched on the many different activities I do as an independent consultant. I shared a bit about how I handle compensation with clients and how I pay myself. And I ended with some brief comments about getting customers. Links discussed in the show:Time management with Clockify Accounting and invoices with Wave Project management with Jira Project notes with Confluence Computing resources with AWS Microsoft 365 for email, sharepoint, and more as a small business Profit First You can connect with me on LinkedIn and send me a message Send me a message Sign up for my newsletter Copyright Teuscher Solutions LLCAll Rights Reserved

In this episode I discuss using nlmixr for population PK modeling in R. I give an overview of the software package, describe the installation process, and walk through a simple example. Overall, nlmixr is a nice package that can be used for most modeling activities you encounter. It eliminates the need for a license since it is open-source. There are some challenges associated with using R for modeling with large datasets and long-running models. But once those are overcome, this could be a great package for all-around use. Links discussed in the show: nlmixr website nlmixr on github Example R code – remove the .txt file type after download You can connect with me on LinkedIn and send me a message Send me a message Sign up for my newsletterCopyright Teuscher Solutions LLCAll Rights Reserved

In this episode I discuss power calculations using the R package PowerTOST. I gave an introduction to power calculations and the statistical premise. I reviewed bioequivalence study designs that are commonly used for generic drug development, food effect evaluation, and drug-drug interaction studies. Links discussed in the show: PowerTOST R package PowerTOST instructions (scroll down to the Read Me information) Example R code (Change the filetype to .R after downloading) Statistical Power Statistical approaches to establishing Bioequivalence from FDA Calculation of CV You can connect with me on LinkedIn and send me a message Send me a message Sign up for my newsletter Copyright Teuscher Solutions LLC All Rights Reserved

In this episode I share a couple short clips from my conversation with Chad Briscoe and Greg Austin from BioTalk Unzipped (www.biotalkunzipped.com). We chat about a variety of topics including artificial intelligence and challenges with cell therapy development. You can hear the entire conversation on the BioTalk Unizipped podcast or YouTube channel in January. For now, enjoy these clips from the upcoming show! Links discussed in the show: BioTalk Unzipped main page BioTalk Unzipped YouTube channel You can connect with me on ⁠LinkedIn and send me a message⁠⁠ Send me a message⁠⁠ Sign up for my newsletter⁠

In this episode I discuss toxicokinetic analysis. This is the analysis of exposure data to support animal toxicology studies. I review the purpose of toxicology studies and how exposure metrics are used. Then I discuss different blood sampling schemes, and how to calculate exposure parameters for both full profiles and mean profiles. Links discussed in the show: You can connect with me on LinkedIn and send me a message Send me a message Sign up for my newsletter Copyright Teuscher Solutions LLC All Rights Reserved

This episode is a discussion of steady state pharmacokinetics. Steady state occurs when the amount of drug input is equivalent to the amount of drug elimination in a dosing interval. I discuss some key PK parameters at steady state and how to use them. I also discuss different methods of confirming that you have reached steady state. Links discussed in the show: You can connect with me on LinkedIn and send me a message Send me a message Sign up for my newsletter Copyright Teuscher Solutions LLC All Rights Reserved

In this episode I talk about dose proportionality, which is a surrogate for determining if we have linear clearance across a range of dose levels. I discuss 3 different methods that people use to determine dose proportionality along with a recommendation to use the power model method. Links discussed in the show: Power model method You can connect with me on ⁠LinkedIn and send me a message⁠⁠ Send me a message⁠⁠ Sign up for my newsletter⁠

This episode is a discussion of covariate search methods. I give definitions of covariates and predictors, and then I describe 3 different covariate search methods. For each method I describe the pros and cons associated with each one, including bias and time limitations. Links discussed in the show: Evaluation of the Boruta method for covariate selection You can connect with me on LinkedIn and send me a message Send me a message Sign up for my newsletter Copyright Teuscher Solutions LLC All Rights Reserved

In this episode I describe stimulatory indirect response PK-PD models. I describe how they work, how to set up the dataset for NONMEM, and how to code the model in NONMEM. This is the last of 4 episodes on different PK-PD models. Links discussed in the show: Indirect response PK-PD model equations Example NONMEM code for stimulatory indirect response PK-PD model You can connect with me on LinkedIn and send me a message Send me a message Sign up for my newsletter Copyright Teuscher Solutions LLC All Rights Reserved

In this episode I describe inhibitory indirect response PK-PD models. I describe how they work, how to set up the dataset for NONMEM, and how to code the model in NONMEM. This is the third of 4 episodes on different PK-PD models. Links discussed in the show: Indirect response PK-PD model equations Example NONMEM code for inhibitory indirect response PK-PD model You can connect with me on LinkedIn and send me a message Send me a message Sign up for my newsletter Copyright Teuscher Solutions LLC All Rights Reserved

In this episode I describe effect compartment PK-PD models. I describe how they work, a method of creating exploratory plots, how to set up the dataset for NONMEM, and how to code the model in NONMEM. This is the 2nd of 4 episodes on different PK-PD models. Links discussed in the show: Example NONMEM code for effect compartment model You can connect with me on LinkedIn and send me a message Send me a message Sign up for my newsletter Copyright Teuscher Solutions LLC All Rights Reserved

In this episode I describe direct effect PK-PD models. I describe how they work, a method of creating exploratory plots to identify direct effect models, how to set up the dataset for NONMEM, and how to code the model in NONMEM. This is the first of 4 episodes on different PK-PD models. Links discussed in the show: Example NONMEM code for direct effect model You can connect with me on LinkedIn and send me a message Send me a message Sign up for my newsletter Copyright Teuscher Solutions LLC All Rights Reserved

In this episode I discuss different methods of presenting pharmacokinetic and pharmacometrics results. I spoke about using PowerPoint and R Markdown derived HTML files. While I prefer HTML files in nearly all cases, I appreciate that sometimes PowerPoint format is required by some companies. I included multiple suggestions for both PowerPoint and HTML files that can help make the information presentation more effective. Links discussed in the show: Floating table of contents in R Markdown HTML output How to include CSS in your R Markdown Creating tabs in R Markdown Code folding in R Markdown You can connect with me on LinkedIn and send me a message Send me a message Sign up for my newsletter Copyright Teuscher Solutions LLC All Rights Reserved

This episode covers the terminal elimination rate constant calculated using non-compartmental analysis techniques. I reviewed how the rate constant is used to estimate half-life and extrapolate AUC to infinity, reviewed the methods for calculating the terminal rate constant value, and some important points about sample selection. Finally, I gave my reasons that we should ultimately stop talking about this and fretting over the method of calculation. Instead, let’s design better PK experiments with more optimal sampling to capture decline of the drugs we are studying. Links discussed in the show: You can connect with me on LinkedIn and send me a message Send me a message Sign up for my newsletter Copyright Teuscher Solutions LLC All Rights Reserved

This episode covered parallelization in modeling analyses. I spoke about across model parallelization and within model parallelization. I recommended some approaches for choosing how many cores to use in parallelization and also discussed different modeling computer systems you can use. Links discussed in the show: You can connect with me on LinkedIn and send me a message Send me a message Sign up for my newsletter Copyright Teuscher Solutions LLC All Rights Reserved

Today I covered 2 different topics. First, I spoke about residual error models when modeling. I discussed additive, proportional, and power models. I also reviewed combined models and when they can be helpful. Then I spoke about modeling report submission packages. I explained what I put in those packages, how they are used, and some potential changes coming in the future. Links discussed in the show: Publication on model master file You can connect with me on LinkedIn and send me a message Send me a message Sign up for my newsletter Copyright Teuscher Solutions LLC All Rights Reserved

This episode discusses simulations. I group simulations into 4 categories: (1) average response, (2) population, (3) individual, and (4) clinical trial simulations. I discuss details of each of these types of simulations and the different variability terms included in each one. I strongly recommend that we implement more clinical trial simulations in our work. This will help us design and execute more successful clinical trials that take advantage of our existing knowledge about a drug. Enjoy the show and connect with me using the links below if you have any questions. Links discussed in the show: You can connect with me on LinkedIn and send me a message Send me a message Sign up for my newsletter Copyright Teuscher Solutions LLC All Rights Reserved

Today’s show is about different work environments and not scientific topics. Throughout my career I have worked in many different types of companies, and I would like to share some observations with you from those experiences. I have held positions at startup companies or small biotechnology companies, large pharmaceutical companies, contract research laboratories, consulting firms, and working for myself as a consultant, and now as a software developer. Although my work has been focused on clinical pharmacology and pharmacometrics, the jobs and work environments are very different. Links discussed in the show: You can connect with me on LinkedIn and send me a message Send me a message Sign up for my newsletter Copyright Teuscher Solutions LLC All Rights Reserved

Today’s show discussed biosimilar development from a clinical pharmacology perspective. I describe what biosimilar products are and the necessary comparisons to the reference product. I review requirements for PK similarity, PD similarity, immunogenicity, and safety. I also touch on the idea of interchangeability between the biosimilar and reference products. Links discussed in the show: FDA Guidance on Clinical Pharmacology Data to support Biosimilarity (May 2016) FDA Guidance on Demonstrating Interchangeability (May 2019) FDA Q&A on Biosimilarity and Interchangeability (Sep 2023) You can connect with me on LinkedIn and send me a message Send me a message Sign up for my newsletter Copyright Teuscher Solutions LLC All Rights Reserved

Today’s show discussed approaches for modeling absorption profiles. I discussed the rationale behind modeling absorption and then described some common models. These included first-order absorption, zero-order absorption, transit compartments, distributed delay, Weibull, and zero/first order absorption. I also provided my recommendations on how to model absorption. Links discussed in the show: Distributed delay modeling in PK and PD Modeling biphasic formulation of methylphenidate You can connect with me on LinkedIn and send me a message Send me a message Sign up for my newsletter Copyright Teuscher Solutions LLC All Rights Reserved

Today’s show was an overview of Aplos Analytics and the development story for Aplos NCA. Please consider participating in the Early Access Program. Use the link below to learn more about Aplos NCA. Links discussed in the show: Aplos Analytics website Aplos Analytics Contact Us Page You can connect with me on LinkedIn and send me a message Send me a message Sign up for my newsletter Copyright Teuscher Solutions LLC All Rights Reserved

Today’s show is about hepatic impairment clinical studies. I cover the rationale behind evaluating hepatic impairment, common study designs, and key factors in the analysis and interpretation of the study results. I also share a huge announcement about Aplos NCA, a cloud-based solution for calculating NCA PK parameters. Use the link below to learn more about Aplos NCA. Links discussed in the show: FDA guidance EMA guideline Aplos Analytics website You can connect with me on LinkedIn and send me a message Send me a message Sign up for my newsletter Copyright Teuscher Solutions LLC

Today’s episode was about Project Optimus, the FDA initiative to improve dose selection and optimization for oncology products. Julie Bullock was a guest on this episode and shared her expertise as a former oncology clinical pharmacology reviewer at the FDA and as a current consultant in the pharmaceutical industry. Links discussed in the show: Project Optimus FDA List of FDA guidances and publications for Project Optimus May 2022 FDA-ASCO workshop: Getting the Dose Right: Optimizing Dose Selection Strategies in Oncology Sept 2023 Second Annual FDA ASCO WORKSHOP on Getting the Dosage Right (this one focused on combinations) Feb 2024 FDA/AACR Public Workshop: Optimizing Dosages for Oncology Drugs You can connect with Julie on LinkedIn You can connect with me on LinkedIn and send me a message Send me a message Sign up for my newsletter Copyright Teuscher Solutions LLC All Rights Reserved

Today’s show is about TMDD or target-mediated drug disposition models. I review the scientific and physiologic basis for TMDD models, how to review data and determine if a TMDD model is needed. I review the various modeling approaches along with my recommendations for specific TMDD models. I hope this information helps you understand how to recognize TMDD behaviors and the options for modeling that data. Links discussed in the show: A tutorial on target-mediated drug disposition (TMDD) models Dynamics of target-mediated drug disposition: characteristic profiles and parameter identification You can connect with me on LinkedIn and send me a message Send me a message Sign up for my newsletter Copyright Teuscher Solutions LLC All Rights Reserved

Today’s episode is about communication for scientists. I believe that improvements in communication skills can have a greater impact on your career and work than technical skills. Michael Piperno, an expert in communication and leadership skills joins me to discuss communication challenges and solutions for clinical pharmacologists and pharmacometricians. Links discussed in the show: You can connect with Michael On his website On LinkedIn On his blog On his podcast Subscribe to Michael’s newsletter View upcoming leadership and communication workshops You can connect with me You can connect with me on ⁠LinkedIn and send me a message⁠⁠ Send me a message⁠⁠ Sign up for my newsletter⁠ Copyright Teuscher Solutions LLC All Rights Reserved

Today’s episode is about cell therapies, including CAR T-cell theraphy for cancer. I give an overview of cell therapy and the challenges of clinical pharmacology in this new area of research. Links discussed in the show: CAR T-cell Therapy Image You can connect with me on LinkedIn and send me a message Send me a message Sign up for my newsletter Copyright Teuscher Solutions LLC All Rights Reserved

Happy New Year! Today’s episode is all about allometric scaling in pharmacokinetic and pharmacodynamics. In particular, I’ll discuss how to use it for scaling from adults to pediatrics and for selection of first in human doses. Links discussed in the show: Boxenbaum manuscript FDA guidance on First in Human doses You can connect with me on LinkedIn and send me a message Send me a message Sign up for my newsletter Copyright Teuscher Solutions LLC All Rights Reserved

This is the last podcast for 2023. Thank you for listening throughout the year! In today’s episode I talk about computer system validation for pharmacometrics. I review my experience with validation in multiple companies over 20 years and discuss what auditors and FDA inspectors want to see. Links discussed in the show: Computer system validation guidance for medical devices Computer systems used in clinical trials Computer system assurance guidance for medical devices EMA guidance on computer systems and electronic data in clinical trials You can connect with me on LinkedIn and send me a message Send me a message Sign up for my newsletter Copyright Teuscher Solutions LLC All Rights Reserved

In today’s episode I cover 4 different modeling approaches: QSP, PBPK, PopPK, and PKPD. All of these are methods for analyzing data to predict either drug concentrations, or a response variable. But each method is developed in a different way and has different assumptions and limitations. Links discussed in the show: You can connect with me on LinkedIn and send me a message Send me a message Sign up for my newsletter Copyright Teuscher Solutions LLC All Rights Reserved

In today’s episode I discuss BLQ handing for both non-compartmental and modeling analysis approaches. I discuss how BLQ samples are defined, methods for analyzing them, and situations when you should use different analysis approaches. Links discussed in the show: FDA guidance on bioanalytical method validation ICH M10 guidance on bioanalytical method validation Handling data below the limit of quantitation in mixed effects models Ways to fit a PK model with some data below the quantification limit You can connect with me on LinkedIn and send me a message Send me a message Sign up for my newsletter Copyright Teuscher Solutions LLC All Rights Reserved

In today’s episode I covered the different types of drug interactions, followed by features of clinical drug evaluation studies recommended in the guidance. Then I will review recommendations for both stand-alone clinical drug interaction studies, as well as nested drug interaction studies. I’ll finish with recommended approaches for interpreting drug interaction study results and expressing that information in drug labeling. Links discussed in the show: Prevalence and factors associated with polypharmacy: a systematic review and meta-analysis by Delara et al. FDA guidance on clinical drug interactions FDA guidance on in vitro drug interactions FDA guidance on therapeutic protein drug interactions EMA guideline on drug interactions You can connect with me on LinkedIn and send me a message Send me a message Sign up for my newsletter Copyright Teuscher Solutions LLC All Rights Reserved

In today’s episode I discuss the evaluation of pharmacokinetics in patients with impaired renal function. I include information from both the US FDA and EMA guidance documents linked below. I discuss the determination of when a dedicated renal impairment study is needed, characteristics of the study design and how to analyze and interpret the results. Links discussed in the show: • FDA guidance on PK in patients with impaired renal function • EMA guidance on Evaluation of PK in patients with decreased renal function • You can connect with me on LinkedIn and send me a message. • Send me a message • Sign up for my newsletter Copyright Teuscher Solutions LLC All Rights Reserved

This episode is a discussion on model evaluation and selection. I discussed diagnostic plots using predictions and residuals. I covered approaches for model selection and factors to consider. The focus of this episode is on models that predict continuous endpoints like drug concentration, biomarkers, or other continuous endpoints. Several figures are mentioned in the podcast and links to those images can be found below. Links discussed in the show: Figure 1: Observed vs Predicted for single-subject model (example of a good model fit). Figure generated using ggplot in R. Figure 2: Observed vs Predicted for single-subject model (example of a poor model fit) using logarithmic scales. Figure generated using ggplot in R. Figure 3: Observed vs Population and Individual Predicted for population model. Figures generated using ggCertara package in R. Figure 4: Weighted residuals versus time, time after dose, and population prediction for population model. Figures generated using ggCertara package in R. You can connect with me on LinkedIn and send me a message Do you need help with model selection? Send me a message Sign up for my newsletter Copyright Teuscher Solutions LLC All Rights Reserved

This episode is a discussion of the FDA guidance “Exposure-Response Relationships”. The relationship between drug exposure and response is critical to any determination of the safety and effectiveness of a drug product. In this episode I discuss the regulatory applications of exposure-response, the exposure-response relationships over time, the design of studies to collection exposure-response information, and modeling exposure-response relationships. Links discussed in the show: • FDA guidance “Exposure-Response Relationships” • ICH E4 guideline “Dose-Response Information” • You can connect with me on LinkedIn and send me a message • Send me a message • Sign up for my newsletter Copyright Teuscher Solutions LLC All Rights Reserved