Evaluation of the Efficacy and Safety of Indigo Naturalis Oil Extract in the Topical Therapy of Psoriasis Vulgaris---Dosage Determination (I)

Psoriasis is an ancient and universal non-infectious inflammatory skin disease that affects about 25 million people in North America and Europe and more than one hundred thousand people in Taiwan. Therapy of psoriasis is still a challenge for the physician because psoriasis is a relapsing and incurable disease and causes shame, embarrassment and a compromised lifestyle. The use of indigo naturalis ointment to treat psoriasis has been proven effective in our previous clinical studies, which demonstrated the efficacy and safety of topical indigo naturalis ointment, showing its ability to provide significant improvement of psoriatic skin lesions. However, the smell and the deep blue color of indigo naturalis, which can slightly stain blue the targeted skin area as well as the clothes of the patient, may ultimately negatively impact patient compliance. Recently, we developed a new formulation in which indigo naturalis powder is refined using olive oil and impurities such as lime and indigo blue are filtered out. This refinement reduces the blue discoloration of skin and clothes, making the treatment more user-friendly. We had observed an equavilent efficacy of the refined form of indigo naturalis ointment on treating psoriasis as the crude form. However, it is necessary to determine an appropriate dose of the refined form, regarding its efficacy and safety. In this study, 100 patients with chronic plaque psoriasis will be enrolled. These patients will be randomized into 5 groups: 200 μg/g,100 μg/g, 50 μg/g, 25 μg/g, 0 μg/g indirubin. The oinment will be applied topically on each of 2 bilaterally symmetrical psoriatic plaque lesions of the same patient twice a day (in the morning and at night) for 8 weeks. These patients will be followed up with or without applying the ointment for another 12 and 20 weeks. Efficacy will be assessed by 2 blinded observers on the basis of clinical scores, including induration, scaling, erythema and clearing percentage. How the efficacy varied with the thickness, morphology, and syndrome of blood heat, blood dryness and blood stasis of psoriasis will also be studied. The patients’ subjective efficacy, safety, and life quality also will be assessed. Moreover, blood and urine sample will be collected at weeks 0, 8 and 12 for the following analyses: hematology, serum chemistry, routine urine, serum indirubin and biomarkers such as, IL2, and TNF-α so that its pharmoco-mechanism will be studied.

Project ID:PC10108-0483
External Project ID:NSC101-2325-B182-018