nlmixr2autoinit (version 1.0.0)

Fit_2cmpt_iv: Fit intravenous pharmacokinetic data to a two-compartment linear elimination model

Description

Fits intravenous (IV) pharmacokinetic data to a two-compartment model with first-order elimination using the naive pooled data approach. Supports multiple estimation methods provided by nlmixr2 and can optionally return only predicted concentrations to support efficient simulation workflows.

Usage

Fit_2cmpt_iv(
  data,
  est.method,
  input.cl,
  input.vc2cmpt,
  input.vp2cmpt,
  input.q2cmpt,
  input.add,
  return.pred.only = FALSE,
  ...
)

Value

If return.pred.only = TRUE, returns a data.frame

with a single column cp (predicted concentrations). Otherwise, returns a fitted model object produced by nlmixr2.

Arguments

data

A data frame containing IV pharmacokinetic data formatted for nlmixr2,

est.method

Estimation method to use in nlmixr2. Must be one of: "rxSolve", "nls", "nlm", "nlminb", or "focei".

input.cl

Initial estimate of clearance (CL).

input.vc2cmpt

Initial estimate of central volume of distribution (V1).

input.vp2cmpt

Initial estimate of peripheral volume of distribution (V2).

input.q2cmpt

Initial estimate of inter-compartmental clearance (Q).

input.add

Initial estimate of the additive residual error.

return.pred.only

Logical; if TRUE, returns a data frame with only predicted concentrations (cp) for all observations in the input data.

...

Additional arguments passed to nlmixr2(), such as a user-defined control = foceiControl(...) or other control settings.

Author

Zhonghui Huang

Examples

 # \donttest{
dat <- Bolus_2CPT
# Fit using 'nls'
Fit_2cmpt_iv(
  data = dat,
  est.method = "nls",
  input.cl = 4,
  input.vc2cmpt = 70,
  input.vp2cmpt = 40,
  input.q2cmpt = 4,
  input.add = 10
)
# Return only predicted concentrations
Fit_2cmpt_iv(
  data = dat,
  est.method = "rxSolve",
  input.cl = 4,
  input.vc2cmpt = 70,
  input.vp2cmpt = 40,
  input.q2cmpt = 4,
  input.add = 0,
  return.pred.only = TRUE
)
# }