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Analysis of Chromameter Results Obtained from Corticosteroid-Induced Skin Blanching. I: Manipulation of Data

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Abstract

Purpose. One of the unresolved issues in the FDA Guidance document for topical corticosteroid bioequivalence testing is the method of manipulation suggested for the chromameter data. The purpose of this study was to manipulate the instrumental data from a typical blanching study in a number of ways to investigate the appropriateness of these procedures for comparison with the subjective visually-assessed results.

Methods. The human skin blanching assay methodology routinely practiced in our laboratories was utilised and the vasoconstriction produced by two corticosteroid formulations of different potency was assessed visually and instrumentally by use of a Minolta chromameter. The instrumental data were corrected for zero-time and unmedicated site readings. In addition, Euclidean distances were calculated using all data generated by the instrument.

Results. Individually the a-, b- and L-scale chromameter values are imprecise and there is negligible vasoconstriction response recorded for the moderately potent formulation. Arithmetical manipulation of the data as suggested by the FDA does not appear to improve the quality of the data in any way. Euclidean distance analysis more closely resembles the visual data and appears to have better precision.

Conclusions. It is clear that mathematical correction of chromameter data is unnecessary, especially since the instrumental data are extremely imprecise. Furthermore, the assessment of each individual chromameter index does not adequately characterise the blanching response profile. It is therefore suggested that Euclidean distance may be a better measure on which to base an analysis of bioequivalence than the truncated data set methodology currently suggested by the FDA.

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REFERENCES

  1. A. W. McKenzie and R. B. Stoughton. Arch. Derm. 86:608–610 (1962).

    Google Scholar 

  2. J. M. Haigh and I. Kanfer. Int. J. Pharm. 19:245–262 (1984).

    Google Scholar 

  3. C. Queille-Roussel, C. Poncet, and H. Schaefer. Br. J. Dermatol. 124:264–270 (1991).

    Google Scholar 

  4. L. K. Pershing, L. D. Lambert, V. P. Shah, and S. Y. Lam. Int. J. Pharm. 86:201–210 (1992).

    Google Scholar 

  5. E. W. Smith, E. Meyer, J. M. Haigh, and H. I. Maibach. J. Dermatol. Treat. 2:69–72 (1991).

    Google Scholar 

  6. E. W. Smith, E. Meyer, J. M. Haigh, and H. I. Maibach. In R. L. Bronaugh and H. I. Maibach (eds.), Percutaneous Absorption Vol. 2. Marcel Dekker, New York, 1989, pp. 443–460.

    Google Scholar 

  7. V. P. Shah, C. C. Peck, and J. P. Skelly. Arch. Dermatol. 125:1558–1561 (1989).

    Google Scholar 

  8. E. W. Smith, E. Meyer, J. M. Haigh, and H. I. Maibach. In R. L. Bronaugh and H.I. Maibach (eds.), Percutaneous absorption. Mechanisms—Methodology—Drug Delivery. Vol. 2. Marcel Dekker, New York, 1989, pp. 443–460.

    Google Scholar 

  9. P. Clarys, L. Wets, A. Barel, and B. Gabard. J. Eur. Acad. Dermatol. Venereol. 5:250–257 (1995).

    Google Scholar 

  10. S. Y. Chan and A. Li Wan Po. J. Pharm. Pharmacol. 44:371–378 (1992).

    Google Scholar 

  11. M. J. Waring, L. Monger, D. A. Hollingsbee, G. P. Martin, and C Marriott. Int. J. Pharm. 94:211–222 (1993).

    Google Scholar 

  12. Guidance: topical dermatologic corticosteroids: in vivo bioequivalence. Division of Bioequivalence, Office of Generic Drugs, Food and Drug Administration, Rockville, MD. June 1995.

  13. P. H. Demana, E. W. Smith, R. B. Walker, J. M. Haigh, and I. Kanfer. Pharm. Res. 14:303–308 (1997).

    Google Scholar 

  14. J. M. Haigh, E. Meyer, E. W. Smith, and I. Kanfer. Int. J. Pharm. 152:179–184 (1997).

    Google Scholar 

  15. L. K. Pershing. Drug Info. J. 29:923–934 (1995).

    Google Scholar 

  16. E. W. Smith, E. Meyer, and J. M. Haigh. Drug. Res. 40:618–621 (1990).

    Google Scholar 

  17. J. W. Moore and H. H. Flanner. Pharm. Tech. 20:64–74 (1996).

    Google Scholar 

  18. P. Clarys, A. O. Barel, and B. Gabard. In K. R. Brain, V. J. James and K. A. Walters (eds.), Prediction of Percutaneous Penetration. Vol. 3b. STS Publishing, Cardiff, 1993, pp. 502–510.

    Google Scholar 

  19. E. W. Smith, E. Meyer, and J. M. Haigh. In H. I. Maibach and C. Surber (eds.), Topical Corticosteroids. Karger, Basel. 1992, pp. 65–73.

    Google Scholar 

  20. R. S. Hunter and R. W. Harold. The Measurement of Appearance, 2nd Edition, Wiley-Interscience, New York, 1987.

    Google Scholar 

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Authors and Affiliations

  1. School of Pharmaceutical Sciences, Rhodes University, Grahamstown, 6140, South Africa

    Eric W. Smith

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  1. Eric W. Smith
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  2. John M. Haigh
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  3. Roderick B. Walker
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Smith, E.W., Haigh, J.M. & Walker, R.B. Analysis of Chromameter Results Obtained from Corticosteroid-Induced Skin Blanching. I: Manipulation of Data. Pharm Res 15, 280–285 (1998). https://doi.org/10.1023/A:1011926920834

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