This event was hosted in close connection with:
1-day nlmixR2 face-to-face workshop @ PMXAC-2025
Pharmacometrics Africa supports the use of open-source software, and was therefore pleased to partner with the nlmixR development team to offer a 1-day hands-on course on nlmixr2 to delegates attending DHA-2025 and PMXAC-2025 in-person at the IDI campus in Makerere University, Kampala.
The nlmixr2 package is an R-based open-source nonlinear mixed-effects modeling software package that is comparable with commercial pharmacometric tools and is suitable for regulatory submissions. Access to open-source tools like nlmixr2 enables students in LMIC settings to continue practicing beyond the course without the burden of purchasing a commercial licence.
Sharon Sawe chaired the workshop – and guided the face-to-face talks by Catriona Waitt who set the African context and Bonginkosi Ndzamba who provided an introduction to PKPD. Thereafter plenary lectures were delivered via a ZOOM link by Rik Schoemaker, Joe Standing, Justin Wilkins and Matthew Fidler. The hands-on exercises were tutored by Sharon Sawe, Innocent Asiimwe, Bonginkosi Ndzamba, Aida Kawuma, Allan Kengo, Francis Williams Ojara and Rashidah Nakamyuka.
All recordings and lecture slides are available for review on this site.
Course objectives:
- Introduce core PKPD and pharmacometric principles, including dose–response relationships, variability, mechanistic vs empirical models, and mixed-effects modelling.
- Showcase the capabilities and the open-source ecosystem of nlmixr2, including its history, current features, estimation methods, interoperability (e.g. with NONMEM/Monolix), and future development roadmap.
- Demonstrate practical applications via case studies to illustrate how modelling informs drug development, clinical decision-making and regulatory review for several therapeutic areas.
- Promote capacity building and collaboration in quantitative clinical pharmacology emphasising transparent workflows, data sharing, clinical–PK integration, and tools for teaching, automation, and reproducibility.
Overview of Clinical Pharmacokinetics at IDI– Catriona Waitt
Catriona outlines how clinical pharmacokinetics at IDI integrates clinical data, physiologically based PK, and population PK approaches to support evidence-based therapeutic decisions . She emphasizes the continuous feedback loop between clinical teams and pharmacokinetic data analysts, supported by strong capacity building, transparent data sharing, and diverse collaborative research.
Catriona Waitt is a Professor of Clinical Pharmacology and Global Health at the University of Liverpool, and has been based at the Infectious Diseases Institute, Makerere University College of Health Sciences since 2014. Her research focuses on drug dosing, efficacy and safety in complex and understudied populations, particularly pregnant and breastfeeding mothers and their infants. Her work draws together clinical trials, observational clinical studies, pharmacometrics, social science and public engagement and involvement. Because of the importance of pharmacometrics to study design and interpretation in these complex populations, her team emphasises continued capacity building in the discipline, including with the launch of the Uganda Chapter of Pharmacometrics Africa in 2021.
Introductory lecture on PKPD – Bonginkosi Sfiso
Bongi’s presentation introduces the role of modern quantitative clinical pharmacology and pharmacometrics in drug development. He explains how mathematical and statistical models link drug exposure and response to guide clinical decisions and regulatory evaluation . He explains fundamental PKPD concepts including dose–response relationships, variability, compartmental and mechanistic models, and nonlinear mixed-effects modelling that are used to quantify differences between patients.
Bonginkosi Ndzamba is a clinical pharmacist and lecturer at Rhodes University (pharmacology division), specializing in clinical pharmacology. He holds a Bachelor of Pharmacy and a Master’s in Clinical Pharmacy from Sefako Makgatho Health Sciences University (South Africa), along with an MPhil in Clinical Pharmacology (Pharmacometrics) from the University of Cape Town, South Africa. He was part of the 2023 cohort of the Applied Pharmacometrics Training fellowship by Pharmacometrics Africa. Currently pursuing a PhD in clinical pharmacokinetics and precision dosing for critically ill patients.
Simulation and parameter estimation with rxode2 and nlmixr2 - Rik Schoemaker
Rik introduces simulation and parameter estimation using rxode2 and nlmixr2, including model definition, solving differential equations, and performing mixed-effects parameter estimation . He highlights advanced capabilities such as interfacing with NONMEM and Monolix through babelmixr2 and nonmem2rx, enabling the import of existing models into the nlmixr2 framework. Rik concludes by demonstrating practical applications through hands-on sessions, including PK and PKPD model building, diagnostics, visual predictive checks, and Bayesian post-hoc estimation .
Rik Schoemaker was born in 1963 in The Netherlands and obtained an MSc (Cum Laude) in Biology with a specialisation in Theoretical Biology from the Free University of Amsterdam in 1987. He worked as modeller and statistician at the Reproductive Endocrinology and Fertility Research outpatient clinic at the Free University Hospital in Amsterdam from 1987-1989 after which he joined the Centre for Human Drug Research (CHDR) in Leiden from 1989-2007. At CHDR he worked as statistician, pharmacokineticist and mathematical modeller, and was involved in all aspects of early phase drug development. While at CHDR, he obtained his PhD on Modelling Repeated Measurements in Clinical Pharmacology in 1999. In 2000 he became a Registered Biostatistician of the Netherlands Society for Statistics and Operations Research (VVS). Rik subsequently worked at Exprimo from 2007-2015 as senior consultant, hugely expanding his modelling and simulation skills, running over 20 full-scale projects for a range of clients with applications in scaling adult to paediatric PK and PK/PD, tumour growth modelling, adverse event and effect modelling using repeated ordered categorical data, viral dynamics modelling, modelling repeated daily seizure counts in epilepsy, and naturally numerous population pharmacokinetic projects. After he left Exprimo, Rik founded Occams in June 2015. Rik lives in The Netherlands.
Rik is a member of the team developing nlmixr2 and is also the 2017 recipient of the International Society of Pharmacometrics (ISoP) Leadership Award, which recognizes outstanding and sustained leadership, mentorship, and outreach contributions to the field of pharmacometrics and to the development of the strategic vision for the future direction of the field.
Rik is author and co-author of over 180 publications, including a number of original research articles in the field of PK/PD modelling. Rik was actively involved in organizing the PAGE meeting from 1996 to 2021, and additionally develops tools to aid in automatic report generation.
Introduction to shinyMixR & Personalised drug regimens with posologyr and rxode2 - Justin Wilkins
In these 2 recordings, Justin provides a comprehensive overview of the nlmixr2 ecosystem accessible via the graphical user interface shinyMixR. He then proceeds to show tools for population PKPD modeling, optimal design (via PopED and babelmixr2) and individualized dosing (via posologyr). He explains how these tools integrate to streamline model development, diagnostics, design evaluation, and personalized therapy decisions, illustrated through practical examples and hands-on workflows. It concludes by highlighting additional utilities—such as reporting frameworks, model libraries, and automated initialization—to support efficient and reproducible pharmacometrics analyses
Justin Wilkins was born in Bellville, South Africa in 1974. After completing his PhD thesis on the PK of rifampicin, isoniazid, and pyrazinamide at the University of Cape Town in 2004 (following a BSc (Hons) and an MSc in the pharmacoeconomics of malaria), Justin moved to Sweden to join Uppsala University as a postdoctoral researcher, where he worked on modelling techniques for describing disease progression in acute stroke and a multiple-dose implementation of the transit absorption model, as well as developing tools for visual and numerical predictive checks. Justin began his industry career when he joined Novartis in Basel in 2006, where he provided pharmacometric support for projects in respiratory disease and oncology; at the same time, he played a central role in launching the DDMoRe consortium. Justin joined Exprimo in 2010, and while there, amassed considerable experience in a wide range of therapeutic areas and modelling applications before leaving to join the newly-founded Occams in late 2015. Justin lives in Germany.
Justin is the developer of the open-source NONMEM project management tool Census, has been a co-developer of Xpose, and co-led the team developing DDMoRe‘s workflow tool. He is currently part of the development team for a new nonlinear mixed-effects modelling tool, nlmixr2. Justin served as a member of the Board of Directors for the International Society of Pharmacometrics (ISoP) from 2016 to 2021 and served as President of the organization in 2019. He was active in the organisation of the PAGE meeting from 2013 to 2023.
nlmixr2 past present and future – Matthew Fidler
Matt outlines the evolution of nlmixr2, from its early development and foundational milestones to its current status as a robust, open-source R platform for nonlinear mixed-effects modelling . After highlighting major features already implemented he outlines future plans including mixture models, survival modelling, and Bayesian extensions. Matt emphasises the project’s vision of delivering an open-source tool that rivals commercial software and supports regulatory-quality pharmacometric analyses.
Matt Fidler, M.Stat. Ph.D. works as a Director in Pharmacometrics and is the lead in the nlmixr2 ecosystem. He has over 15 years of drug development experience and currently is working in Ophthalmology and Immunology disease areas. He is passionate about open source and nonlinear mixed effects methodology. He started work on the nlmixr2/rxode2 (then nlmixr and RxODE) 2017 and the ecosystem has evolved to allow interchange of common model formats with the new babelmixr2.
Case studies (nlmixr2 use with real world data) – Joe Standing
Joe’s presentation reviews UCL’s extensive experience using nlmixr2 across PK, PD, PKPD modelling, Bayesian TDM, and automated model-building, showing its evolution into the department’s primary pharmacometrics platform . Through 11 case studies—including metformin modelling, paediatric oncology PKPD, SARS-CoV-2 viral dynamics, antibiotic PKPD, and personalised biologic dosing, he is able to generate excitement about nlmixr2’s robustness, regulatory acceptability, and versatility for both research and clinical decision support.
Prof Standing is an academic and hospital pharmacist who holds a PhD in clinical pharmacology, and MSc in Statistics. Prior to becoming a professor he held two UK Medical Research Council academic fellowships (Methodology 2011-2015, Clinician Scientist 2015-2020) which led to the development of a paediatric pharmacometrics research group at the UCL Great Ormond Street Institute of Child Health. The main research interests of the group are in undertaking clinical and pre-clinical pharmacokinetic-
Organisers
Francis Williams Ojara
Francis Williams Ojara is a Post-doctoral pharmacometric modeler at the Infectious Diseases Institute and a lecturer of pharmacology at Gulu University. He holds a Doctorate in Natural Sciences (focusing on Pharmacometrics). His research covers modelling of pharmacokinetic-(and pharmacodynamic) data in oncology and infectious diseases, with current interests in understudied populations such as the pediatrics and pregnant mothers. He has strong interest in training and mentoring scholars into pharmacometrics and establishing potent global networks to support the growth of pharmacometrics in Uganda and Africa.
Rashidah Nakamyuka
Rashidah Nakamyuka is a Biomedical Scientist with a Master’s Degree in Pharmacology from Makerere University and currently works as a Pharmacology Lecturing Assistant at ISBAT University, Uganda. She was part of the 2025 cohort of the Applied Pharmacometrics Training fellowship by Pharmacometrics Africa and has participated in multiple additional trainings with the organization. Through her Master’s research and the Pharmacometrics Africa training, Rashidah has gained practical experience in pharmacometric modeling and analysis using tools such as R programming, Monolix, NONMEM, and Nlmixr2.
Allan Kengo
Dr Kengo is a pharmacometrician and clinical researcher dedicated to transforming how medicines are developed, optimized, and prescribed. With a Ph.D. in Pharmacology from the University of Cape Town, he specializes in population pharmacokinetic modelling and has advanced understanding of complex drug interactions in tuberculosis–HIV therapy. He also lectures pharmacology at Gulu University, where he mentors the next generation of scientists and clinicians. Through the fusion of quantitative modelling and real-world clinical insight, Dr. Kengo delivers patient-centered, data-driven solutions that improve treatment outcomes and drive the future of precision medicine.
Sharon Sawe
Sharon Sawe is a PhD student in Pharmacometrics within the Division of Clinical Pharmacology at the University of Cape Town. Originally from Kenya, she has a background in biostatistics and data science and specializes in developing population pharmacokinetic/pharmacodynamic models to optimize drug dosing. Her research focuses on the pharmacokinetics of second-line tuberculosis drugs in pregnant and breastfeeding women, populations historically underrepresented in clinical trials. She applies advanced modelling and simulation approaches to understand drug disposition during pregnancy and lactation, supporting evidence-based dosing, and improving treatment outcomes in maternal and child health. She is passionate about leveraging state-of-the-art quantitative pharmacology methods, and is enthusiastic about mentoring the next generation of scientists
Innocent Asiimwe
Innocent is a Pharmacometrician at Novartis Pharmaceuticals UK Ltd with over 15 years of experience in data science, pharmacometrics, and clinical research. A pharmacist from Uganda, he specialises in personalised medicine, pharmacogenomics, and real-world evidence.
He trained at the University of Liverpool (MSc, MRes, PhD) and later worked in Prof. Sir Munir Pirmohamed’s group applying large-scale data to understand disease and drug response. He also contributed to the UNITE4TB Pharmacology package, using AI/ML to analyse complex pharmacogenetic and pharmacokinetic datasets to improve treatment for drug-resistant TB.
Innocent serves on the General Board of the Fundisa African Academy of Medicines Development, supports training with Pharmacometrics Africa, and has consulted in PK/PD modelling and simulation. His work aims to advance new therapies and optimise the safe and effective use of existing medicines.
Aida Kawuma
Aida is a pharmacometrician at PumasAI / Makerere University living in Uganda. She trained as a pharmacist at Makerere University, College of Health Sciences where she also obtained a Master’s degree in pharmacology. She holds a PhD in pharmacometrics from the University of Cape Town. She is passionate about training the next generation of African mathematical modellers. She has several years of carrying out community-based medical education. Her interests include safe and effective use of medication and the use of mathematical modelling and simulation techniques to optimize treatment and to improve clinical trial design. She lives in Kampala with her husband and three adorable sons.
Colin Pillai
Goonaseelan (Colin) Pillai is committed to driving programs that develop scientific capability in low and middle-income countries. A clinical pharmacologist who trained in Durban, South Africa, Colin previously worked at the corporate headquarters of Novartis and Roche in Switzerland. He has a specialist interest in the application of non-linear mixed effects models to pharmacokinetic-pharmacodynamic data across a wide range of therapeutic areas. In Pharma, he played leadership roles in bringing internal and external acceptance of applying mathematical models to decision making in drug development. His most recent Pharma role involved establishing programs that allowed sharing scientific expertise and infrastructure with researchers and institutions in LMIC. Colin has held teaching, research and management positions at the Universities of Durban-Westville and Witwatersrand. He acquired his clinical and research experience in hospital and community pharmacy and as a consultant with the SA Medical Research Council’s Tuberculosis Research program, where he ran a unit conducting Phase 1 clinical trials. Colin continues to maintain active academic links with numerous institutions in Africa including via formal Honorary Professorships and Board Member status. Since November 2017, he is a Senior Advisor on capacity development and training programs for global health to the Bill and Melinda Gates Foundation.