DANDRUFF PRODUCTS FINAL MONOGRAPH: FDA ADDS .6% MICRONIZED SELENIUM SULFIDE

DANDRUFF PRODUCTS FINAL MONOGRAPH: FDA ADDS .6% MICRONIZED SELENIUM SULFIDE as an active ingredient under a notice of proposed rulemaking published in the April 5 Federal Register. The NPRM amends the OTC Dandruff, Seborrheic Dermatitis and Psoriasis Control Products Final Monograph to include .6% micronized selenium sulfide for the control of dandruff based on data supporting the efficacy of the ingredient. FDA's December 1991 final monograph for OTC dandruff products only listed 1% unmicronized (not reduced to a fine particle size) selenium sulfide as an active ingredient. FDA's proposal to include .6% micronized selenium sulfide to the monograph was in response to a petition submitted by Selsun Blue manufacturer Ross Labs in 1991. The Abbott subsidiary initially requested that .6% micronized selenium sulfide be listed as a Category I (safe and effective) ingredient in 1987 based on five clinical studies. However, FDA told the firm in October 1989 that only two of the five studies could be deemed "well-controlled clinical trials" and recommended that at least one additional placebo-controlled study of "adequate sample size" be submitted to support the efficacy of the ingredient. Ross Labs submitted a study on the efficacy of .6% micronized selenium sulfide to FDA in 1991, but was told by the agency that the time remaining before publication of the final rule was not sufficient to allow for consideration of the new data. The submission was subsequently considered a petition to amend the final monograph. In the randomized, double-blind, parallel group, placebo- controlled study, 169 subjects were shampooed twice weekly for six weeks with either a .6% micronized selenium sulfide shampoo, a 1% nonmicronized selenium shampoo (the active ingredient in Selsun Blue), or a shampoo with no anti-dandruff ingredients. The two selenium sulfide groups showed a greater mean reduction and rate of reduction in dandruff than the control, FDA said. No significant difference was found between the .6% micronized and 1% nonmicronized groups, according to the agency. "Based on this additional study" and on studies previously submitted by Ross Labs, "the agency tentatively concludes that .6% micronized selenium sulfide is safe and effective for OTC use in the control of dandruff," the notice says. FDA states that manufacturers desiring to market an OTC anti- dandruff product incorporating .6% micronized selenium sulfide must wait until a final monograph amendment is issued. As part of amending the OTC dandruff products final monograph to include the ingredient, FDA also is proposing a specific definition for micronized selenium sulfide: "selenium sulfide which has been finely ground and that has a median particle size of approximately 5 micrometers, with not more than .1% of the particles greater than 15 [micrometers] and not more than .1% of the particles less than .5 [micrometers]." The comment period for the NPRM ends June 5.