nlmixr2 ecosystem
By Matthew Fidler in nlmixr2
June 30, 2025
nlmixr2 ecosystem
I have seen a few new pharmacometrics tools integrated in the nlmixr2 ecosystem recently. I thought I would point out the tools I know that integrate in the nlmixr2 ecosystem.
Some are maintained by our nlmixr2 team, and many are not. For each category, these are ordered alphabetically.
Tools that Enhance nlmixr2’s language
- nlmixr2lib In addition to a model library, it has tools to change model components (like add Weibull absorption, add transit compartments, change standard elimination to Michaleis-Menton absorption; maintained by Bill Denney and developed by the nlmixr2 team). 
- pmxNODE The goal of pmxNODE is to facilitate the implementation of neural ordinary differential equations (NODEs) in pharmacometric software, i.e., Monolix, NONMEM, and nlmixr2 (by Dominic Bräm & language integration by Matt Fidler). 
nlmixr2 run management tool
- shinyMixR
Currently the only run managment tool for nlmixr2isshinyMixR(By Richard Hooijmaijers and colleagues at LAP&P)
Tools to help with standard non-linear estimated models
- ggPMX This tool creates standardized diagnostic plots for tools like Monolix, nlmixr2 and NONMEM (By colleagues sponsored by Novartis). 
- nlmixr2autoinit Creates automatic parameter estimates for a nlmixr2 model. (By Zhonghui Huang and Joe Standing lab at UCL) 
- nlmixr2auto Automated Population Pharmacokinetic Modelling. This package offers serveral optimisation algorithms designed for automated population pharmacokinetic modeling, serving as a valuable tool for pharmacokinetic model selection. (By Zhonghui Huang and Joe Standing lab at UCL) 
- pharmpy Can create - nlmixr2models (and convert between- NONMEMand- nlmixr2models)
- PKNCA With the help of - babelmixr2, you can use- PKNCAto calculate PK parameters that will be used as initial estimates for your population PK model (By Bill Denney and team at Human Predictions)
- tidyvpc integrates and can create visual prediction plots from nlmixr2 models (by James Craig and team at Cetara) 
- vpc Create visual predictive checks, a commonly used diagnostic plot in pharmacometrics, in R, and is used by the default VPCs from nlmixr2 (By Ron Keizer and Bill Denney) 
- xpose.nlmixr2 This integrates the ggplot2 - xposewith- nlmixr2outputs allowing standardized graphs (By Justin Wilkins and collegues)
Tools to help simulation of non-linear models (excluding rxode2)
- Campsis can use the Campsis models to perform a shiny model simulation using rxode2 or mrgsolve. With the professional subscription, you can also convert nlmixr2, Monolix and NONMEM models to campsis format (by Nicolas Luyckx and colleagues at Campsis) 
- ruminate Shiny tool for simulation of complex regimens and designs 
Expanding nlmixr2 beyond estimation and simulation
- OptiDoseR optiDoseR is a package to facilitate the application of the optiDose approach in Monolix, NONMEM, and nlmixr2 (by Dominic Bräm) 
- PopED this allows optimal design methodologies to be applied to a - nlmixr2model using the babelmixr2 package. (Translation written by Matt Fidler; PopED written by Andrew Hooker and colleagues)
- posologyr Personalize drug regimens using individual pharmacokinetic (PK) and pharmacokinetic-pharmacodynamic (PK-PD) profiles. By combining therapeutic drug monitoring (TDM) data with a population model, posologyr offers accurate posterior estimates and helps compute optimal individualized dosing regimens (by Cyril Leven) 
Reporting tools
- nlmixr2rpt Converts nlmixr2 runs to Word and PowerPoint reports (by John Harrold). 
- PharmTeX Can be used to create - LaTeXreports for nlmixr2 (by Christian Hove Claussen)
Conversion tools
- Monolix These models can be imported using - monolix2rx()and exported/run using- monolix’s- "monolix"method. Both are available in babelmixr2. (Conversion routines written by Matt Fidler, Monolix is currently maintained by Simulations Plus).
- NONMEM These models can be imported using - nonmem2rx()and exported/run using- babelmixr2’s- "nonmem"method. Both are available in babelmixr2. (Conversion routines are written by Matt Fidler, NONMEM currently maintained by Bob Bauer and other colleagues at Icon).
- pharmpy Can create - nlmixr2models (and convert between- NONMEMand- nlmixr2models)
- PKPDsim Can convert PKPDsim models to - nlmixr2models (by Ron Keizer and team at InsightRX)
Modeling platform tools
- Campsis can use the Campsis models to perform a shiny model simulation using rxode2 or mrgsolve. With the professional subscription, you can also convert nlmixr2, Monolix and NONMEM models to campsis format (by Nicolas Luyckx and colleagues at Campsis) 
- IQRtools Allows use of nlmixr2 in an integrated environment using a shared language that is translated to nlmixr2 tools. 
- pharmpy Can create - nlmixr2models (and convert between- NONMEMand- nlmixr2models)
- ubiquity Converts ubiquity language into rxode2/nlmixr2 syntax and can use this same interface to convert to NONMEM and Monolix (By John Harrold)