ModelDrug

Antimalarial drug modelling

There are three different ways of modelling antimalarial drug action in OpenMalaria:

1. A simple success/failure model in which drug treatment either clears all infections in the host (treatSimple option in health system / intervention component) or does nothing. This can be extended to include a prophylactic effect which simply removes all new infections for a configurable number of steps in the future.
2. Clearing infections via above method then using Pre-erythrocytic vaccines to probabilistically prevent reinfection (this allows a slightly more realistic prophylactic effect than the above).
3. Explicit pharmacokinetic and pharmacodynamic (PK/PD) modelling of drugs (treatPKPD option in health system / intervention component), linked to a dynamic model of parasite densities in the course of an infection. The treatment schedules and PK/PD parameterisations can be found in the pharmacology library. The drugs structural PK profile can be chosen from one of three PK models (described below).

Structural PK model options

One-compartment PK model

The methodology required to simulate a one-compartment PK model, assuming first-order absorption, linear elimination and multiple doses (without lag time) was described previously in the Winter & Hastings (2011). It requires estimates of the volume of distribution Vd (L/kg) and the drug half-life(days). The half-life is converted to the drug elimination rate λ (/day) using ln(2) / half_life.

Three-compartment PK model