Research Article| Volume 32, ISSUE 2, P357-364, February 2010

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Relative bioavailability of two oral formulations of piroxicam 20 mg: A single-dose, randomized-sequence, open-label, two-period crossover comparison in healthy Mexican adult volunteers

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      Background: Piroxicam is an NSAID indicated for the treatment of rheumatoid diseases. Although there are generic formulations of oral piroxicam marketed in Mexico, a literature search did not identify published data concerning the bioavailability of these formulations in the Mexican population.
      Objectives: The aims of this study were to determine the bioequivalence of a generic (test) and a reference formulation of oral piroxicam 20 mg and to generate data regarding the oral bioavailability of this drug in a Mexican population.
      Methods: This single-dose, randomized-sequence, open-label, 2-period crossover study was conducted in healthy Mexican adult volunteers. Subjects were randomly assigned to receive the test formulation followed by the reference formulation, or vice versa, with a 15-day washout period between doses. Study drugs were administered after a 10-hour overnight fast. For pharmacokinetic analysis, blood samples were drawn at 0 (baseline), 0.5, 1, 1.5, 2, 2.5, 3, 4, 5, 6, 8, 12, 24, 48, 72, 96, 120, and 168 hours after administration. Plasma concentrations of piroxicam were determined using HPLC. The test and reference formulations were to be considered bioequivalent if the 90% CIs for the geometric mean test/reference ratios were within a predetermined range of 80% to 125%. Tolerability was determined using clinical assessment, monitoring of vital signs, laboratory analysis, and subject interviews regarding adverse events (AEs).
      Results: A total of 28 subjects were enrolled (15 men, 13 women; mean [SD] age, 24 [4] years [range, 19–35 years]; weight, 63.0 [8.9] kg [range, 47.5–81.9 kg]; height, 165 [10] cm [range, 149–179 cm]; and body mass index, 23.2 [1.4] kg/m2 [range, 20.6–26.0 kg/m2]). The 90% CIs for piroxicam Cmax, AUC0−∞, and AUC0−∞) were 89.98% to 101.04%, 91.46% to 101.19%, and 93.51% to 105.86%, respectively. Thirteen subjects reported a total of 17 AEs during the study. None of the AEs were considered serious or related to the administered formulations. The most common AE was local postvenipuncture ecchymosis, reported in 8 subjects (28.6%).
      Conclusions: In this small study in healthy Mexican adult subjects, a single 20-mg dose of the test formulation of orally administered piroxicam met the regulatory requirements to assume bioequivalence, based on the rate and extent of absorption. Both formulations were well tolerated. Mexican national registry code: CE-PEC.0875.

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        • Ishizaki T
        • Nomura T
        • Abe T
        Pharmacokinetics of piroxicam, a new nonsteroidal anti-inflammatory agent, under fasting and postprandial states in man.
        J Pharmacokinet Biopharm. 1979; 7: 369-381
        • Rasetti-Escargueil C
        • Grange V
        Pharmacokinetic profiles of two tablet formulations of piroxicam.
        Int J Pharm. 2005; 295: 129-134
      1. Federal Commission for the Protection Against Sanitary Risks (COFEPRIS). List of Drug-Reference Medications [in Spanish], Mexico City, Mexico. September 2008.
        (Accessed February 13, 2009.)
        • World Medical Association (WMA)
        World Medical Association Declaration of Helsinki: Ethical Principles for Medical Research Involving Human Subjects. Adopted by the 18th WMA General Assembly, Helsinki, FinlandJune 1964 (and amended by the 52nd WMA General Assembly, Edinburgh, Scotland, October 2000. Accessed February 13, 2009)
      2. European Agency for the Evaluation of Medicinal Products (EMEA), International Conference on Harmonisation. Guideline for Good Clinical Practice. ICH topic E6 (R1).
        (Accessed February 13, 2009)
        • General Standard Directorate
        Mexican Official Standard NOM177-SSA1-1998, requirement 8.4. Test and procedures to prove that a medication is interchangeable [in Spanish]. Federal Commission for the Protection of Sanitary Risks, Mexico City, Mexico1999
      3. Introduction.
        in: Chow S-C Liu J-p Design and Analysis of Bioavailability and Bioequivalence Studies. 2nd ed. Marcel Dekker, New York, NY2000: 1-30
        • Schuirmann DJ
        A comparison of the two one-sided tests procedure and the power approach for assessing the equivalence of average bioavailability.
        J Pharmacokinet Biopharm. 1987; 15: 657-680
        • US Dept of Health and Human Services (HHS), Food and Drug Administration (FDA), Center for Drug Evaluation and Research (CDER)
        Guidance for Industry. Statistical Approaches to Establishing Bioequivalence.
        (Accessed February 13, 2009)
        • Thomson PLM
        S.A. de C. V. Feldene capsules prescribing information by Pfizer, S.A. de C.V. Diccionario de Especialidades Farmacéuticas 2007 [in Spanish]. 53rd ed. Thomson PLM, Mexico City, Mexico2007: 1657-1659