WILMINGTON, MASSACHUSETTS -- (MARKET WIRE) -- January 23, 2007 -- According to international guidelines published in the January, 2007 issue of the Journal of the American Academy of Dermatology, Photodynamic Therapy (PDT) has been recommended by a consensus group of physicians as a highly effective first-line treatment for actinic keratoses (AKs). PDT, a combination of light therapy and photosensitive topical solution, is often used to treat AKs, a common skin condition that, if left untreated, can lead to squamous cell carcinoma (skin cancer). According to the recommendations, PDT should be considered as a first-line therapy for treating the pre-cancerous lesions. The Levulan PDT system (Levulan® Kerastick® together with the BLU-U® light source) marketed by DUSA Pharmaceuticals, Inc.® (NASDAQ GM: DUSA) is the only currently available PDT treatment approved by the U.S. Food and Drug Administration (FDA) for AKs. It is also available in Canada. In addition, exclusive marketing rights for Levulan PDT have been granted to Stiefel Laboratories, Inc. for Latin America and to Daewoong Pharmaceuticals Co., LTD for certain Asian countries.