US Patent No. 9,107,844 B2; Stiefel Laboratories Inc., Coral Gables, FL, has patented a dual chamber device comprising a first storage-stable benzoyl peroxide-containing composition in suspension in one chamber and a second composition comprising clindamycin or a pharmaceutically-acceptable salt or ester thereof in solution and a retinoid or a pharmaceutically-acceptable salt thereof in a second chamber. When dispensed from the dual chamber device, the first composition and the second composi...