title: Bioequivalence of 250 mg lysine clonixinate tablets after a single oral dose in a healthy female Mexican population under fasting conditions.
abstract: OBJECTIVE
  To evaluate the bioequivalence between two 250 mg-tablets of lysine clonixinate, Dorixina Forte (Siegfried Rhein, México) as reference product, and Prestodol (Farmaceúticos Rayere, S.A., México) as test formulation.
  
  
  METHODS
  26 healthy adult female Mexican volunteers received a single oral dose of 250-mg lysine clonixinate under fasting conditions. The drug was administered following a randomized, two-period, two-sequence, cross-over design. Twelve serial blood samples were collected up to 8 h after dosing, and clonixin (CLX) was measured by ultra-performance liquid chromatography (UPLC) coupled with tandem mass spectrometry. Decimal logarithm values of Cmax and area under the curve (AUC) were used to construct a classic confidence interval at 90% (90% CI). Bioequivalence was established if 90% CI of mean ratios (test/reference) fall within the 0.8-1.25 range.
  
  
  RESULTS
  Volunteers formed a homogeneous population in terms of age (27.2 +/- 6.3 years), weight (55.9 +/- 6.5 kg), height (1.6 +/- 0.04 m), and body mass index (BMI) (22.91 +/- 2.03 kg/m(2)). Reference formulation exhibited the following pharmacokinetics: C(max) (32.39 +/- 8.32 microg/ml); t(max) (0.64 +/- 0.2 h); AUC0-8h (48.92 +/- 16.51 microg x h/ml); t1/2 (1.3 +/- 0.24 h); CLapp (5.64 +/- 1.99 l/h), and Vdapp (10.22 +/- 2.9 l). Concerning bioequivalence, 90% CI were: C(max) (82.32 - 98.79), AUC0-t (94.59-106.29), and AUC(0-inf) (94.61-106.42), with a statistical power of > 0.90 at every tested interval.
  
  
  CONCLUSIONS
  This single-dose study found that both 250-mg immediate-release tablets of lysine clonixinate met the Mexican regulatory criteria for bioequivalence in these volunteers.
authors.affiliation: Clinical Pharmacology Research Service, Hospital General de México, Mexico City, Mexico. gabmarcelin@hotmail.com
authors.forename: G
authors.initials: G
authors.lastname: Marcelín-Jiménez
authors.forename: A C P
authors.initials: AC
authors.lastname: Angeles
authors.forename: A
authors.initials: A
authors.lastname: García
authors.forename: M
authors.initials: M
authors.lastname: Morales
authors.forename: L
authors.initials: L
authors.lastname: Rivera
authors.forename: A
authors.initials: A
authors.lastname: Martín-Del-Campo
mesh_terms: D000284:Administration, Oral; D000328:Adult; D000700:Analgesics / Q000008:administration & dosage / Q000493:pharmacokinetics*; D019540:Area Under Curve; D002853:Chromatography, Liquid / Q000379:methods*; D003002:Clonixin / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000493:pharmacokinetics; D018592:Cross-Over Studies; D004311:Double-Blind Method; D005215:Fasting; D005260:Female; D006207:Half-Life; D006801:Humans; D008239:Lysine / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000493:pharmacokinetics; D008800:Mexico; D013607:Tablets; D053719:Tandem Mass Spectrometry / Q000379:methods; D013810:Therapeutic Equivalency; D014018:Tissue Distribution; D055815:Young Adult
chemical_list: D000700:Analgesics; D013607:Tablets; C089163:lysine clonixinate; D008239:Lysine; D003002:Clonixin