Compositions for topical application comprising a peroxide and retinoid

A composition for topical application comprising as active ingredients

• a solid particulate matter of benzoyl peroxide, and
• a solid particulate matter of all trans retinoic acid, wherein
• at least one of the active ingredients is in the form of first microparticles, and
• each microparticle of the first microparticles contains a solid core consisting of either the solid particulate matter of benzoyl peroxide or the solid particulate matter of all trans retinoic acid, the solid core being coated by a metal oxide layer.

A kit comprising:

• (a) a first composition comprising a peroxide as a first active ingredient;
• and
• (b) a second composition comprising a retinoid as a second active ingredient;
• wherein
• at least one of said first and said second active ingredient is present in a solid core of a microparticle, the solid core being coated by a metal oxide layer, and
• the solid core of the microparticle consisting of either said first active ingredient, or said second active ingredient.