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Cited by 45Thyroid Disorders and TreatmentsPharmaceutical studies and practicesAnalytical Methods in Pharmaceuticals

Pharmacokinetic equivalence of a levothyroxine sodium soft capsule manufactured using the New Food and Drug Administration potency guidelines in healthy volunteers under fasting conditions

Colucci, Philippe, D'Angelo, Pina, Mautone, Giuseppe, Scarsi, Claudia, Ducharme, Murray P·2011·Therapeutic Drug Monitoring
DOI 10.1097/ftd.0b013e318217b69f
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Abstract

OBJECTIVE: To assess the pharmacokinetic equivalence of a new soft capsule formulation of levothyroxine versus a marketed reference product and to assess the soft capsule formulated with stricter potency guidelines versus the capsule before the implementation of the new potency rule. METHOD: Two single-dose randomized two-way crossover pharmacokinetic equivalence studies and one dosage form proportionality single-dose study comparing low, medium, and high strengths of the new formulation. All three studies were performed in a clinical setting. Participants were healthy male and female adult subjects with normal levothyroxine levels. A total of 90 subjects participated in the three studies. RESULTS: Pharmacokinetic parameters were calculated on baseline- adjusted concentrations. The first pharmacokinetic equivalence study compared the levothyroxine sodium soft capsule formulation (Tirosint) with the reference Synthroid tablets and the two products were considered bioequivalent. The dosage form proportionality study compared the 50-, 100-, and 150-μg test capsules strengths dosed at the same level (600 μg) and all three strengths were considered equivalent when given at the same dosage. The last study compared the test capsule used in the first two studies with a new capsule formulation following the new potency guideline (±5%) set forward by the Food and Drug Administration and the two capsules were considered bioequivalent. Doses were well tolerated by subjects in all three studies with no serious adverse events reported. CONCLUSIONS: The levothyroxine soft capsule formulated with the stricter new potency guideline set forward by the Food and Drug Administration met equivalence criteria in terms of rate and extent of exposure under fasting conditions to the reference tablet formulation. Clinical doses of the capsule formulation can be given using any combination of the commercialized strengths.

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Crossref · 10.1097/ftd.0b013e318217b69f

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8 of 8 references verified0 citation errors · 0 not checkable

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  • Colucci et al. observed that gel capsules met revised FDA potency guidelines of 95%-105% and met equivalence criteria.

    “Colucci et al. (111) observed that gel capsules met the revised FDA potency guidelines of 95%-105% (103,104) and also met equivalence criteria.”

    From Guidelines for the Treatment of Hypothyroidism: Prepared by the American Thyroid Association Task Force on Thyroid Hormone Replacement (2014) · cites this paper as [111]

  • Colucci et al conducted a clinical trial in 24 healthy volunteers according to the FDA-approved pharmacokinetic protocol for bioequivalence, and confirmed pharmacokinetic equivalence between LT4 soft gel capsules and tablets.

    “Colucci et al conducted a clinical trial in 24 healthy volunteers according to the Food and Drug Administration–approved pharmacokinetic protocol for bioequivalence. The study confirmed the pharmacokinetic equivalence between LT4 soft gel capsules and tablets (221).”

    From Levothyroxine: conventional and novel drug delivery formulations. (2023) · cites this paper as [221]

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Authors
Colucci, P., D'Angelo, P., Mautone, G., Scarsi, C., & Ducharme, M. P.
Affiliations
  • Université de Montréal (CA)
  • IBSA Institut Biochimique (Switzerland) (CH)
Corresponding author
  • Colucci, Philippe
  • Ducharme, Murray P
ORCID
Venue
Therapeutic Drug Monitoring
Publisher
Ovid Technologies (Wolters Kluwer Health)
Published
2011-06
Volume
33
Issue
3
Pages
355-361
ISSN
0163-4356 (ISSN-L)
DOI
10.1097/ftd.0b013e318217b69f
OpenAlex
W1997946000
Cited by
45
References
8
Citations by year
2026: 1 · 2025: 2 · 2024: 4 · 2023: 2 · 2022: 6 · 2021: 3 · 2020: 1 · 2019: 3 · 2018: 2 · 2017: 3 · 2016: 5 · 2015: 3 · 2014: 4 · 2013: 2 · 2012: 3
FWCI
2.36
Type
journal article
Language
en
Open access
closed
Locations
  • Therapeutic Drug Monitoring (publishedVersion)
  • PubMed (publishedVersion)
Topics
  • Health Sciences › Medicine › Endocrinology, Diabetes and Metabolism › Thyroid Disorders and Treatments
  • Health Sciences › Medicine › Pediatrics, Perinatology and Child Health › Pharmaceutical studies and practices
  • Physical Sciences › Chemistry › Analytical Chemistry › Analytical Methods in Pharmaceuticals
Keywords
levothyroxine sodium, bioequivalence, single-dose pharmacokinetics, fasting conditions, healthy volunteers, thyroid hormone replacement
MeSH terms
Adult, Capsules, Chemistry, Pharmaceutical, Dosage Forms, Fasting, Female, Humans, Male, Tablets, Therapeutic Equivalency, Thyroxine, United States, United States Food and Drug Administration, Cross-Over Studies

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