nca {clinPK}

Perform an NCA based on a NONMEM-style dataset

Description

Perform an NCA based on a NONMEM-style dataset

Usage

nca(
  data = NULL,
  dose = 100,
  tau = 24,
  method = c("log_linear", "log_log", "linear"),
  scale = list(auc = 1, conc = 1),
  dv_min = 0.001,
  t_inf = NULL,
  fit_samples = NULL,
  weights = NULL,
  extend = TRUE,
  has_baseline = TRUE,
  route = c("iv", "oral", "im", "sc")
)

Arguments

data

data.frame with time and dv columns

dose

dose amount

tau

dosing frequency, default is 24.

method

'linear', 'log_linear' (default), or 'log_log'

scale

list with scaling for auc and concentration ('conc')

dv_min

minimum concentrations, lower observations will be set to this value

t_inf

infusion time, defaults to 0

fit_samples

vector of sample indexes used in fit to calculate elimination rate, e.g. 'c(3,4,5)'. If not specified (default), it will evaluate which of the last n samples shows the largest adjusted R^2 when log-transformed data is fitted using linear regression, and use those samples in the estimation of the elimination rate.

weights

vector of weights to be used in linear regression (same size as specified concentration data), or function with concentration as argument.

extend

perform an 'extended' NCA, i.e. for the calculation of the AUCs, back-extend to the expected true Cmax to also include that area.

has_baseline

does the included data include a baseline? If 'FALSE', baseline is set to zero.

route

administration route, 'iv' (intravenous, default), 'oral', 'sc' (sub-cutaneous), or 'im' (intra-muscular).

Value

Returns a list of three lists:

pk

Lists pk parameters.

• kel: elimination constant

• t_12: half-life

• v: distribution volume

• cl: clearance

descriptive

Lists exposure parameters.

• cav_t: the average concentration between the first observation and the last observation without extrapolating to tau

• cav_tau: the average concentration from 0 to tau

• cmin: the extrapolated concentration at time = tau

• c_max_true: only available if extend = TRUE, the extrapolated peak concentration

• c_max: only available if extend = FALSE, the observed maximum concentration

• auc_inf: the extrapolated AUC as time goes to infinity

• auc_24: the extrapolated AUC after 24 hours, provided no further doses are administered

• auc_tau: the extrapolated AUC at the end of the dosing interval

• auc_t: the AUC at the time of the last observation

settings

Lists dosing information.

• dose: dose quantity

• tau: dosing interval

Examples

data <- data.frame(time = c(0, 2, 4, 6, 8, 12, 16),
                   dv   = c(0, 10, 14, 11, 9, 5, 1.5))
nca(data, t_inf = 2)