Dow Pharmaceutical Sciences, Inc.: halobetasol propionate

Act for halobetasol propionate and tazarotene lotion, 0.01%/0.045%.

Per 21 CFR 314.125(b)(4), there is insufficient information about the drug to determine whether the product is safe for use under the conditions prescribed, recommended, or suggested in its proposed labeling.

Specifically, you did not provide sufficient nonclinical toxicology data to support NDA approval as it was determined that an adequate bridge to the listed drugs, Ultravate (halobetasol propionate) Cream, 0.05% and Tazorac (tazarotene) Cream, 0.05%, was not established based on the information submitted in the NDA.

In particular, the relative bioavailability assessment showed that the bioavailability of the proposed combination product, halobetasol propionate and tazarotene lotion, 0.01%/0.045%, was higher than each of the listed drugs for the individual monads.

It is recommended that protocols for carcinogenicity studies be submitted to the Division for evaluation by the Executive Carcinogenicity Assessment Committee of CDER.