<p>Tazarotene is a retinoid prodrug which is converted to its active form, the cognate carboxylic acid of tazarotene, by rapid deesterification in animals and man. In cell culture and in vitro models of skin, tazarotene suppresses expression of MRP8, a marker of inflammation present in the epidermis of psoriasis patients at high levels. In human keratinocyte cultures, it inhibits cornified envelope formation, whose build-up is an element of the psoriatic scale.</p>