Structural model - Long infusion short half life one compartment model
Route of administration - IV infusion
Dosage Regimen - 500000 ug
Number of Subjects - 1
This exercise deals with the drug having short half life.
To build a model for drug having short half life given as a very long infusion up to 3 months.
Call the "necessary" libraries to get started.
using Random using Pumas using PumasUtilities using CairoMakie
To build a one compartment model for a drug having short half life given a long infusion for 3 months.
pk_46 = @model begin @metadata begin desc = "One Compartment Model" timeu = u"hr" end @param begin "Volume at Steady State (L)" tvvss ∈ RealDomain(lower=0) "Clearance (L/hr)" tvcl ∈ RealDomain(lower=0) Ω ∈ PDiagDomain(2) "Additive Error" σ_add ∈ RealDomain(lower=0) end @random begin η ~ MvNormal(Ω) end @pre begin Vss = tvvss*exp(η) Cl = tvcl*exp(η) end @dynamics begin Central' = - (Cl/Vss)*Central end @derived begin cp = @. Central/Vss """ Observed Concentration (ug/L) """ dv ~ @. Normal(cp, σ_add) end end
PumasModel Parameters: tvvss, tvcl, Ω, σ_add Random effects: η Covariates: Dynamical variables: Central Derived: cp, dv Observed: cp, dv
Parameters provided for simulation are as below.
tv represents the typical value for parameters.
$Vss$ - Steady state volume (L)
$CL$ - Clearance (L/hr)
param = ( tvvss = 35.6, tvcl = 61, Ω = Diagonal([0.0,0.0]), σ_add = 0.196337)
(tvvss = 35.6, tvcl = 61, Ω = [0.0 0.0; 0.0 0.0], σ_add = 0.196337)
A dose of 500000 ug was given as an Intravenous Infusion to a single subject for over 3 months.
ev1 = DosageRegimen(500000, time = 0, cmt = 1, duration = 2016) sub1 = Subject(id = 1, events = ev1)
Subject ID: 1 Events: 2
Simulate the data after the administration of Infusion
Random.seed!(123) sim_sub1 = simobs(pk_46, sub1, param, obstimes = 0.5:0.1:2100)
f, a, p = sim_plot(pk_46, [sim_sub1], observations = :cp, color = :redsblues, linewidth = 4, axis = (xlabel = "Time (hrs)", ylabel = "PK46 Concentrations (μg/L)", xticks = 0:500:2000)) axislegend(a) f