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Open Access 01-07-2019 | Letter to the Editor

Authors’ Reply to Coste et al.: “Levothyrox^® New and Old Formulations: Are they Switchable for Millions of Patients?”

Authors: Didier Concordet, Peggy Gandia, Jean-Louis Montastruc, Alain Bousquet-Mélou, Peter Lees, Aude A. Ferran, Pierre-Louis Toutain

Published in: Clinical Pharmacokinetics | Issue 7/2019

Excerpt

We are pleased to respond to the letter of Coste at al. [1] as follows. Nowhere in our article is any claim made to analyse the problem of symptoms reported with the new formulation of Levothyrox^®. Our sole aim was to challenge scientifically the principle of using an average bioequivalence (ABE) approach to document a switchability issue. This is a particular concern, given that substitution of a new formulation was imposed on several million patients. …

Coste J, Bertagna X, Zureik M. Comment on: “Levothyrox^® New and Old Formulations: Are they Switchable for Millions of Patients?”. Clin Pharmacokinet. 2019. https://doi.org/10.1007/s40262-019-00779-9.CrossRefPubMed

Anonymous. “Guideline on the investigation of bioequivalence” (EMA, London, 2010). http://www.ema.europa.eu/docs/en_GB/document_library/Scientific_guideline/2010/01/WC500070039.pdf. Accessed 28 Apr 2019.

Anonymous. Guidance for industry: bioequivalence studies with pharmacokinetic endpoints for drugs submitted under an ANDA. Draft guidance. U.S. Department of Health and Human Services Food and Drug Administration Center for Drug Evaluation and Research (CDER) December 2013 Biopharmaceutics. Available from: https://www.fda.gov/downloads/Drugs/GuidanceComplianceRegulatoryInformation/Guidances/UCM377465.pdf. Accessed 28 Apr 2019.

Anonymous. Levothyrox; preliminary assessment report. Pharmacokinetic comment on a generic application. Rapport interne ANSM sur les études de bioéquivalence (15/09/2017). ANSM. https://www.ansm.sante.fr/content/download/110115/1395469/version/1/file/Rapport+d%C3%A9valuation+bioequivalence+_+Levothyrox.pdf. Accessed 28 Apr 2019.

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Concordet D, Gandia P, Montastruc J-L, Bousquet-Mélou A, Lees P, Ferran A, et al. Levothyrox^® new and old formulations: are they switchable for millions of patients? Clin Pharmacokinet. 2019. https://doi.org/10.1007/s40262-019-00747-3. (Epub ahead of print).

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Title: Authors’ Reply to Coste et al.: “Levothyrox® New and Old Formulations: Are they Switchable for Millions of Patients?”
Authors: Didier Concordet
Peggy Gandia
Jean-Louis Montastruc
Alain Bousquet-Mélou
Peter Lees
Aude A. Ferran
Pierre-Louis Toutain
Publication date: 01-07-2019
Publisher: Springer International Publishing
Published in: Clinical Pharmacokinetics / Issue 7/2019
Print ISSN: 0312-5963
Electronic ISSN: 1179-1926
DOI: https://doi.org/10.1007/s40262-019-00780-2

At a glance: The STEP trials

Springer Medicine

Authors’ Reply to Coste et al.: “Levothyrox^® New and Old Formulations: Are they Switchable for Millions of Patients?”

Excerpt

At a glance: The STEP trials

Springer Medicine

Excerpt

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