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Comment
. 2020 Feb;59(2):265-267.
doi: 10.1007/s40262-019-00847-0.

Comment on: "Why Were More Than 200 Subjects Required to Demonstrate the Bioequivalence of a New Formulation of Levothyroxine with an Old One?"

Axel Krebs-Brown  1 , Alain Munafo  2 , Sumedh Gaikwad  1 , Bogumila Urgatz  1 , Claire Castello-Bridoux  3
Affiliations
Comment

Comment on: "Why Were More Than 200 Subjects Required to Demonstrate the Bioequivalence of a New Formulation of Levothyroxine with an Old One?"

Axel Krebs-Brown et al. Clin Pharmacokinet. 2020 Feb.
No abstract available

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Conflict of interest statement

Axel Krebs-Brown, Alain Munafo, Sumedh Gaikwad, Bogumila Urgatz, and Claire Castello-Bridoux are all employees of Merck KGaA, Darmstadt, Germany, or of one of its affiliates.

Figures

Fig. 1
Fig. 1
Power to conclude ABE versus sample size in a 2 × 2 crossover study. The calculations assume a mixed intra-subject CV of 23.7%, and an ABE acceptance range of 0.9–1.11. The blue line shows the power assuming no difference between the formulations; the red line allows for a 5% difference in exposure. ABE average bioequivalence, CV coefficient of variation, GMR geometric mean ratio
See this image and copyright information in PMC

Comment in

Comment on

References

    1. Concordet D, Gandia P, Montastruc JL, Bousquet-Mélou A, Lees P, Ferran AA, et al. Why were more than 200 subjects required to demonstrate the bioequivalence of a new formulation of levothyroxine with an old one? Clin Pharmacokinet. 2019 doi: 10.1007/s40262-019-00812-x. - DOI - PMC - PubMed
    1. Gottwald-Hostalek U, Uhl W, Wolna P, Kahaly GJ. New levothyroxine formulation meeting 95–105% specification over the whole shelf-life: results from two pharmacokinetic trials. Curr Med Res Opin. 2017;33:169–174. doi: 10.1080/03007995.2016.1246434. - DOI - PubMed
    1. Concordet D, Gandia P, Montastruc JL, Bousquet-Mélou A, Lees P, Ferran A, et al. Levothyrox® new and old formulations: are they switchable for millions of patients? Clin Pharmacokinet. 2019;58(7):827–833. doi: 10.1007/s40262-019-00747-3. - DOI - PMC - PubMed
    1. Munafo A, Krebs-Brown A, Gaikwad S, Urgatz B, Castello-Bridoux C. Comment on “Levothyrox® new and old formulations: are they switchable for millions of patients?” [letter] Clin Pharmacokinet. 2019;58(7):969–971. doi: 10.1007/s40262-019-00785-x. - DOI - PMC - PubMed
    1. Concordet D, Gandia P, Montastruc J-L, Bousquet-Mélou A, Lees P, Ferran AA, et al. Authors’ reply to Castello-Bridoux et al.: “Comment on levothyrox® new and old formulations: are they switchable for millions of patients?” [letter] Clin Pharmacokinet. 2019;58(7):973–975. doi: 10.1007/s40262-019-00786-w. - DOI - PMC - PubMed

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