Population pharmacokinetic and pharmacodynamic modeling of transformed binary effect data of triflusal in healthy Korean male volunteers: a randomized, open-label, multiple dose, crossover study

Table 2 Final estimates of population PK and PD parameters

Parameter	Description (units)	Estimates from final model		Bootstrap results	Shrinkage (%)
Parameter	Description (units)	Estimate	% RSE^a	Median (95% CI)	Shrinkage (%)
Fixed effect
Pharmacokinetic
CL/F = θ ₁ * (weight/71.65)^θ4
θ ₁	TV of CL/F (L/h) for subject whose weight = 71.65 kg	0.200	2.7	0.1998 (0.1995 – 0.2002)
θ ₄	Exponent of weight proportional to CL/F	0.845	17.4	0.840 (0.830 – 0.850)
V _d/F = θ ₂ * (weight/71.65)
θ ₂	TV of V _d (L) for subject whose weight = 71.65 kg	8.300	2.7	8.281 (8.267 – 8.295)
k _f = θ ₃	TV of k _f (h^-1)	0.341	15.1	0.345 (0.341 – 0.348)
Pharmacodynamic
θ ₅	TV of EC ₅₀ (μg/mL)	84.9	4.0	85.19 (84.98 – 85.40)
θ ₆	TV of γ	19.2	22.4	20.70 (20.32 – 21.08)
BSV (%CV)
Pharmacokinetic
ω ₁ ²	BSV for CL/F	14.9	21.0	14.4 (14.3 – 14.5)	0.6
ω ₂ ²	BSV for V _d	9.5	57.8	8.6 (8.4 – 8.8)	40.2
ω ₃ ²	BSV for k _f	88.0	26.5	73.5 (72.8 – 74.1)	10.5
Pharmacodynamic
ω ₄ ²	BSV for EC ₅₀	21.8	28.4	21.4 (21.2 – 21.5)	8.3
ω ₅ ²	BSV for γ	0 (Fixed)	NE	-	-
Residual error (σ²)^b
Proportional error		0.098	6.5	0.0977 (0.0973 – 0.0981)	11.5

% RSE, % relative standard error; CI, confidence interval; CL/F, oral clearance; TV, typical value at population level; V _d /F, oral volume of distribution; k _f, first-order formation rate constant; EC ₅₀, HTB concentration at which the probability of IPA is 50%; γ, shape factor; BSV, between-subject variability; % CV, % coefficient of variation; NE, not estimated.
^a% RSE is calculated from ω².
^bAdditive residual error was not selected.

ISSN: 2050-6511