Pharmaceutical Research

, Volume 31, Issue 4, pp 837–846 | Cite as

Current Challenges in Bioequivalence, Quality, and Novel Assessment Technologies for Topical Products

  • Avraham Yacobi
  • Vinod P. Shah
  • Edward D. Bashaw
  • Eva Benfeldt
  • Barbara Davit
  • Derek Ganes
  • Tapash Ghosh
  • Isadore Kanfer
  • Gerald B. Kasting
  • Lindsey Katz
  • Robert Lionberger
  • Guang Wei Lu
  • Howard I. Maibach
  • Lynn K. Pershing
  • Russell J. Rackley
  • Andre Raw
  • Chinmay G. Shukla
  • Kailas Thakker
  • Nathalie Wagner
  • Elizabeta Zovko
  • Majella E. Lane
Expert Review


This paper summarises the proceedings of a recent workshop which brought together pharmaceutical scientists and dermatologists from academia, industry and regulatory agencies to discuss current regulatory issues and industry practices for establishing therapeutic bioequivalence (BE) of dermatologic topical products. The methods currently available for assessment of BE were reviewed as well as alternatives and the advantages and disadvantages of each method were considered. Guidance on quality and performance of topical products was reviewed and a framework to categorise existing and alternative methods for evaluation of BE was discussed. The outcome of the workshop emphasized both a need for greater attention to quality, possibly, via a Quality-By-Design (QBD) approach and a need to develop a “whole toolkit” approach towards the problem of determination of rate and extent in the assessment of topical bioavailability. The discussion on the BE and clinical equivalence of topical products revealed considerable concerns about the variability present in the current methodologies utilized by the industry and regulatory agencies. It was proposed that academicians, researchers, the pharmaceutical industry and regulators work together to evaluate and validate alternative methods that are based on both the underlying science and are adapted to the drug product itself instead of single “universal” method.


bioequivalence dermatologic topical product generic in vitro in vivo quality-by-design 



The views expressed here are the views of the scientists and do not represent the policy of their respective agencies or organization.

The Product Quality Research Institute (PQRI) is a non-profit consortium of organizations working together to generate and share timely, relevant, and impactful information that advances drug product quality and development.

By virtue of its diverse membership, PQRI provides a unique forum to focus critical thinking, conduct research, exchange information, and propose methodology or guidance to pharmaceutical companies, regulators, and standard setting organizations.


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Copyright information

© Springer Science+Business Media New York 2014

Authors and Affiliations

  • Avraham Yacobi
    • 1
  • Vinod P. Shah
    • 2
  • Edward D. Bashaw
    • 3
  • Eva Benfeldt
    • 4
  • Barbara Davit
    • 3
  • Derek Ganes
    • 5
  • Tapash Ghosh
    • 3
  • Isadore Kanfer
    • 6
  • Gerald B. Kasting
    • 7
  • Lindsey Katz
    • 8
  • Robert Lionberger
    • 3
  • Guang Wei Lu
    • 9
  • Howard I. Maibach
    • 10
  • Lynn K. Pershing
    • 11
  • Russell J. Rackley
    • 12
  • Andre Raw
    • 3
  • Chinmay G. Shukla
    • 3
  • Kailas Thakker
    • 13
  • Nathalie Wagner
    • 14
  • Elizabeta Zovko
    • 15
  • Majella E. Lane
    • 16
  1. 1.DOLE Pharma LLCNew YorkUSA
  2. 2.Pharmaceutical ConsultantNorth PotomacUSA
  3. 3.U.S. Food and Drug AdministrationSilver SpringUSA
  4. 4.Department of DermatologyUniversity of Copenhagen Roskilde HospitalCopenhagenDenmark
  5. 5.Ganes Pharma Inc.TorontoCanada
  6. 6.Rhodes UniversityGrahamstownSouth Africa
  7. 7.University of CincinnatiCincinnatiUSA
  8. 8.Biostudy Solutions LLCWilmingtonUSA
  9. 9.AllerganIrvineUSA
  10. 10.University of California–San FranciscoSan FranciscoUSA
  11. 11.University of Utah Health Sciences CenterSalt Lake CityUSA
  12. 12.Mylan Pharmaceuticals IncMorgantownUSA
  13. 13.Tergus Pharma LLCDurhamUSA
  14. 14.Galderma R&DSophia AntipolisFrance
  15. 15.Forest Research InstituteNew YorkUSA
  16. 16.University College London School of PharmacyLondonUK

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