Fenretinide [N-4-hydroxyphenyl, 4HPR] is a synthetic retinoid derived from vitamin A with pro-apoptotic and anti-inflammatory properties. Studies have shown that at high concentrations fenretinide is an effective anti-neoplastic agent, regulating cell growth and differentiation. We have recently demonstrated that fenretinide, at doses 5-10× lower than for cancer treatment, has protective effect against bacterial infection and osteoporosis in Cftr-knockout mice. The effect of fenretinide as a potential treatment for allergic asthma induced inflammation has not been evaluated in asthmatics. The goal of this study was to determine if, by normalizing inflammatory mediators, fenretinide would be able to alleviate the symptoms associated with allergic asthma.