SANTA BARBARA, Calif., Jan. 11 -- Miravant Medical Technologies has begun treating patients in a phase II clinical trial of PhotoPoint photodynamic therapy (PDT) for plaque psoriasis, a chronic skin disease in which the immune system triggers accelerated growth of skin cells. The clinical trial is an open-label, drug and light dose-ranging study to assess the safety and efficacy of single topical PhotoPoint treatments. The study targets 54 patients with moderate plaque-type psoriasis who will be treated at various dermatology centers and followed for up to 12 weeks. PhotoPoint PDT uses Miravant's proprietary light-activated topical drug MV9411 to locally treat psoriatic plaques, abnormal skin lesions that can cause patients discomfort or pain. In the two-step investigational procedure, varying doses of PhotoPoint MV9411 are applied directly to psoriatic plaques, followed by a light treatment. This proprietary drug completed a phase I drug-only safety study with healthy volunteers in 2001.