Overview of Pumas

Pumas is a collection of a modules that facilitate workflows related to data analysis in the pre-clinical and clinical stages of drug development. This document provides a general overview of each of these workflows.

The Pumas NLME Workflow

The core Pumas NLME workflow is:

  1. Define a PumasModel or a PumasEMModel. Both these models define the structure of the NLME model.
  2. Define a Subject and Population. These structure specify the dosage regimens of the patients, their covariates, and possible observation data to fit against. This can be done programmatically or by reading in tabular input data.
  3. Define a param NamedTuple for the parameters describing the structure of the PumasModel or the PumasEMModel. For simulation, these are the parameter values to simulate with. For estimation, these are the initial conditions.
  4. Call the model API functions (simobs and fit) to perform the simulations and estimation. Both functions act on the pieces defined before.
  5. Post-process the results of a model or compare between different models using automated workflows such evaluate_diagnostics
  6. Generate automated reports of your model.

This workflow directly integrates with usage of the Julia language. For example, one may define Julia functions and use these functions within the definition of a PumasModel. Additionally, one may write loops that defines Subjects or new random params and use these in simulations via simobs. Thus Pumas gives the core tools for handling NLME models but is a lean system that allows the user to seamlessly utilize the larger Julia ecosystem to solve their problem.

After fits and simulations are performed, the returned objects have smart defaults that allow for inspection. Each returned object has a DataFrame overload so that DataFrame(ret) displays the simulation or estimation as tabular data. Additionally, each returned object has a plotting function that gives a standardized plot (with options) of the simulation or estimation. All of the internal values are accessible and the fields are documented within the manual.

The Pumas NCA Module Workflow

The NCA submodule works by:

  1. Defining an NCASubject or NCAPopulation, either programmatically or by reading tabular data in the PumasNCADF format.
  2. Running NCA functions on the subject or population, such as NCA.auc, or generating a full NCA report using run_nca followed by report.

Each of the NCA data objects have smart defaults that allow for inspection. Each of them has a plotting function that provides a standardized plot (with options) of the NCA data and results.

The Pumas Bioequivalence Workflow

The Bioequivalence module works by:

  1. Reading in tabular data that support various designs
  2. Perform the bioequivalence analysis on the tabular data using pumas_be

The Pumas Optimal Design Workflow

The optimal design module of Pumas currently includes sample time optimization. The sample time optimization workflow in Pumas is:

  1. Define the model and subject template or population
  2. Define time windows in human readable times and dates
  3. Define resource and logistic constraints
  4. Choose the optimality type (D/A/T optimality)
  5. Optimize the sample times
  6. View the optimal sample times for each subject in human readable times and dates