PK profile — dose scenarios:
Dose Your Drug (—) Selected Cell (— —)
Min Dose for Your Drug
Min Dose of Sel. Cell
MMV Criteria for Late Lead (400 mg)

Your Drug

Human PK/PD Parameters
Predicted Doses

About the LAI Parameter Explorer

Version 1.4.1

Description

The LAI Parameter Explorer is an R Shiny web application for Long-Acting Injectable (LAI) pharmacokinetics / pharmacodynamics (PK/PD) simulations. It calculates the minimum dose needed to maintain unbound plasma concentrations above the in-vivo minimum inhibitory concentration (MIC) for a specified coverage duration, across a grid of clearance and volume of distribution values.

The app is developed by Medicines for Malaria Venture (MMV) to support early-stage decision-making for LAI antimalarial drug candidates.

Release Notes — v1.4.1

  • User Guide links and citation: the User Guide tab now has links, in its top-right corner, to open the guide in its own browser tab and to download it as a Word (.docx) file. The links are plain page content, so readers that cannot display the embedded guide, such as AI assistants, can still reach the guide text. The guide now also states its authors, version and copyright, and offers a suggested citation (#72).

Release Notes — v1.4.0

  • An error in one calculation or display element no longer ends the session: it is caught and logged, and the rest of the app keeps working (SafeShiny, as in MMVSola and MMVFree).
  • Updated to MMVshiny 1.8.0.

Release Notes — v1.3.1

  • Fixed the in-vivo Hill/EC50 calculation to match MMVFree: the static in-vitro Hill is now capped at 7.9 before being converted to a dynamic Hill (an uncapped Hill above the underlying model's calibrated range of 1-8 was silently returning an infinite EC50/MIC,u for compounds with an extreme average in-vitro Hill, rather than a real "infinite MIC"), and the PRR Lag Time input - previously collected but never actually used in the PD calculation - is now applied via the same lag-time correction MMVFree uses.

Release Notes — v1.3.0

  • Compound parameters can now be pre-filled by opening the app with a URL query string — the intended use is a link from MMVFree, carrying a compound's predicted parameters across automatically instead of requiring manual entry. See the User Guide for the accepted parameters and a worked example link.
  • Added an app logo to the navbar.

Release Notes — v1.2.0

  • Replaced the "How to?" tab with a User Guide tab covering app usage and how to obtain initial unbound CL,u, Vss,u, and IC50,u values from MMVFree.
  • Added a LAI Bioavailability input (default 0.8).
  • The Min Dose / Max MICu heatmap colours now reflect the MMV Criteria for Late Lead dose (400 mg).
  • Split the “Your Drug” table into separate “Human PK/PD Parameters” and “Predicted Doses” tables; the Human PK/PD Parameters table now includes a Source column showing whether each value was entered by the user or derived from a formula.
  • Clearer terminology throughout: “Absorption T½” / “Elimination T½”, and IC50,u to make explicit that the in-vitro IC50 input must be unbound.
  • The PK profile dose-scenario checkboxes in the left panel are now colour-coded to match their corresponding lines in the PK profile plot.
  • Fixed a calculation bug where the static (not PRR-adjusted) Hill coefficient was passed into the EC50 translation, causing a ~5% error in the predicted EC50 and in-vivo MICu.
  • Fixed the dose calculation to use separate in-vitro and patient parasite growth rates, aligning with MMVSola/MMVFree.
  • Aligned the default fast absorption rate with MMVSola's reference estimate.
  • Reordered the fast/slow absorption rate inputs to match the order shown in the plots.
  • Updated the simulated unbound clearance (CL,u) grid to 1, 3, 10, 30, 100 mL/min/kg; Max MICu is now the default plot type; removed the unused MIC-by-T½ plot type.
  • General UI polish: clearer notation and rounding, a combined PK profile legend, and various plot/table sizing and alignment fixes.

Release Notes — v1.0.0

  • navbarPage layout with Prediction, How to?, and About tabs.
  • Auto-run simulation: results update automatically on input change (~800 ms debounce).
  • Improved YourDrug summary table: combined single table with input and result sections.
  • SVG plot rendering for sharp, artifact-free heatmaps and PK profiles.
  • Algebraic dose solver (uniroot): ~600× faster than the original bisection approach.
  • Responsive left panel: input fields resize correctly with the browser window.
  • Numeric input spinners removed; mousewheel and arrow keys no longer change values.

Contact

For questions or feedback, please contact:

Medicines for Malaria Venture (MMV)
Route de Pré-Bois 20, 1215 Geneva 15, Switzerland
www.mmv.org