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Comment on “Levothyrox® New and Old Formulations: Are they Switchable for Millions of Patients?”

Clinical Pharmacokinetics volume 59, pages 281–282 (2020)Cite this article

A Letter to the Editor to this article was published on 05 December 2019

The Original Article was published on 04 April 2019

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References

  1. Concordet D, Gandia P, Montastruc JL, Bousquet-Melou A, Lees P, Ferran A, et al. Levothyrox® new and old formulations: are they switchable for millions of patients? Clin Pharmacokinet. 2019;58(7):827–33.

    Article  Google Scholar 

  2. Food and Drug Administration. Guidance for industry: Average, population, and individual approaches to establishing bioequivalence. Rockville: U.S. Department of Health and Human Services, Center for Drug Evaluation and Research (CDER); 1999.

    Google Scholar 

  3. Food and Drug Administration. In vivo bioequivalence studies based on population and individual bioequivalence approaches. Rockville: U.S. Department of Health and Human Services FDA, Center for Drug Evaluation and Research (CDER); 1997.

    Google Scholar 

  4. Chow S-C. Individual bioequivalence-a review of FDA draft guidance. Drug Inf J. 1999;33(2):435–44.

    Article  Google Scholar 

  5. Hsuan FC. Some statistical considerations on the FDA draft guidance for individual bioequivalence. Stat Med. 2000;19(20):2879–84.

    Article  CAS  Google Scholar 

  6. Endrenyi L, Taback N, Tothfalusi L. Properties of the estimated variance component for subject-by-formulation interaction in studies of individual bioequivalence. Stat Med. 2000;19(20):2867–78.

    Article  CAS  Google Scholar 

  7. Yu Y, Teerenstra S, Neef C, Burger D, Maliepaard M. A comparison of the intrasubject variation in drug exposure between generic and brand-name drugs: a retrospective analysis of replicate design trials. Br J Clin Pharmacol. 2016;81(4):667–78.

    Article  CAS  Google Scholar 

  8. Maliepaard M, Hekster YA, Kappelle A, van Puijenbroek EP, Elferink AJ, Welink J, et al. Requirements for generic anti-epileptic medicines: a regulatory perspective. J Neurol. 2009;256(12):1966–71.

    Article  Google Scholar 

  9. Cristofoletti R, Rowland M, Lesko LJ, Blume H, Rostami-Hodjegan A, Dressman JB. Past, present, and future of bioequivalence: improving assessment and extrapolation of therapeutic equivalence for oral drug products. J Pharm Sci. 2018;107(10):2519–30.

    Article  CAS  Google Scholar 

  10. Faasse K, Cundy T, Petrie KJ. Medicine and the media. Thyroxine: anatomy of a health scare. BMJ. 2009;339:b5613.

  11. Saravanan P, Chau WF, Roberts N, Vedhara K, Greenwood R, Dayan CM. Psychological well-being in patients on “adequate” doses of L-thyroxine: results of a large, controlled community-based questionnaire study. Clin Endocrinol (Oxf). 2002;57:577–85.

    Article  CAS  Google Scholar 

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Authors and Affiliations

  1. Medicines Evaluation Board, Utrecht, The Netherlands

    Yang Yu & Marc Maliepaard

  2. Department of Pharmacology and Toxicology, Radboud University Medical Centre, Nijmegen, The Netherlands

    Yang Yu & Marc Maliepaard

Authors
  1. Yang Yu
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  2. Marc Maliepaard
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Correspondence to Yang Yu.

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No external funding was used in the preparation of this manuscript.

Conflict of interest

Yang Yu and Marc Maliepaard declare that they have no potential conflicts of interest that might be relevant to the contents of this manuscript.

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Yu, Y., Maliepaard, M. Comment on “Levothyrox® New and Old Formulations: Are they Switchable for Millions of Patients?”. Clin Pharmacokinet 59, 281–282 (2020). https://doi.org/10.1007/s40262-019-00850-5

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  • DOI: https://doi.org/10.1007/s40262-019-00850-5