Comparative potency of formulations of mometasone furoate in terms of inhibition of 'PIRHR' in the forearm skin of normal human subjects measured with laser doppler velocimetry.

BACKGROUND AND AIMS Topical glucocorticoid formulations are widely used for effective treatment and control of a variety of dermatoses. Mometasone furoate is a newer corticoid that has high potency but low systemic toxicity. Pharmaceutical factors are known to significantly influence potency and systemic absorption of topically applied glucocorticoids. We studied the potency of "Elocon", a topical formulation of mometasone furoate, compared with two other branded formulations of the same corticoid. METHODS Corticoid potency was measured by employing a pharmacodynamic parameter of an inhibitory effect of the corticoid on post-ischemic-reactive-hyperemic-response (PIRHR) in human forearm skin under occlusive dressing. The PIRHR was expressed in terms of % increase in the skin blood flow (SBF) as measured with laser doppler velocimetry (LDV). RESULTS All three active branded formulations of mometasone furoate produced significant inhibition of PIRHR. The AUC(0-2 min) of PIRHR was ( Mean +/- SEM ), Control = 213.52 +/- 11.80, Placebo = 209.77 +/- 19.31, Formulation A = 119.83 +/- 13.71, Formulation C = 53.67 +/- 4.85 and Formulation D = 111.46 +/- 22.87. Formulation "C" exhibited significantly higher topical anti-inflammatory potency than formulations "A" or "D". CONCLUSIONS Thus, branded formulations of the same glucocorticoid, mometasone furoate significantly differed in their topical anti-inflammatory potency. "Elocon" was significantly more potent than the two other branded formulations studied.