Comparative study on the bioequivalence of two different gabapentin formulations. A randomised, two-period, two-sequence, crossover clinical trial in healthy volunteers.
The bioequivalence of two capsule formulations containing 400 mg gabapentin (CAS 60142-96-3) was assessed in 24 healthy volunteers in an open, randomised, crossover, 2 periods x 2 sequences, with a minimum washout period of 7 days, single-dose study. Plasma samples were obtained at fixed time points, over 48 h (baseline (pre-dose), +0.5 h, +1 h, +1.5, +2, +2.5, +3, +3.5, +4, +8, +5, +6, +8, +10, +12, +24, +36 and +48 h after administration) and gabapentin concentrations were determined by means of an HPLC-MS method (LLOQ 50.2 ng/mL). Pharmacokinetic parameters used for bioequivalence assessment (AUCtlast, AUCinf and Cmax) were determined from the gabapentin concentration data using non-compartmental analysis. The results showed that all 90 % confidence intervals (obtained by ANOVA) were all within the predefined ranges: 93.87-111.87 % for Cmax 94.04-108.21 % for AUCtlast and 94.23-108.29 % for AUCinf. Consequently, this bioequivalence study was well designed in order to conclude that the test formulation and reference formulation were bioequivalent in terms of rate and extent of absorption.
Medical Department, Grupo Tecnimede, Prior Velho, Portugal. dmed.ct.tecnimede@mail.telepac.pt
Susana
S
Almeida
Augusto
A
Filipe
Ana
A
Almeida
Rosa
R
Antonijoan
Consuelo
C
García-Gea
Ignasi
I
Gich
Manuel
M
Barbanoj
Maria
M
Cruz Caturla
D000293:Adolescent; D000328:Adult; D000588:Amines / Q000008:administration & dosage / Q000493:pharmacokinetics*; D000927:Anticonvulsants / Q000008:administration & dosage / Q000493:pharmacokinetics*; D019540:Area Under Curve; D002214:Capsules; D002626:Chemistry, Pharmaceutical; D018592:Cross-Over Studies; D003509:Cyclohexanecarboxylic Acids / Q000008:administration & dosage / Q000493:pharmacokinetics*; D005260:Female; D000077206:Gabapentin; D006801:Humans; D008297:Male; D013810:Therapeutic Equivalency; D005680:gamma-Aminobutyric Acid / Q000008:administration & dosage / Q000493:pharmacokinetics*
D000588:Amines; D000927:Anticonvulsants; D002214:Capsules; D003509:Cyclohexanecarboxylic Acids; D005680:gamma-Aminobutyric Acid; D000077206:Gabapentin