DUSA Pharmaceuticals, Inc., a dermatology company that is developing and marketing Levulan Photodynamic Therapy (PDT), announced that the United States Patent and Trademark Office (USPTO) has completed its re-examination of US Patent No. 5,079,262, “Method of detection and treatment of malignant and non-malignant lesions utilizing 5-aminolevulinic acid.”

In its latest communication, the USPTO issued a Notice of Intent to Issue Ex Parte Re-examination Certificate which affirms the patent’s original seven claims and adds eight claims. This patent covers the use of aminolevulinic acid, the active ingredient in DUSA’s Levulan Kerastick, for the treatment of actinic keratoses with light. This patent will expire on September 30, 2013. Additional patents cover DUSA’s Levulan Kerastick formulation of aminolevulinic acid HCl in conjunction with its proprietary blue light technology until June 2019.

Robert F. Doman, DUSA’s president and CEO, said, “We are pleased that the Patent Office has confirmed the validity of one of our key Levulan PDT patents. DUSA placed this patent into re-examination at the patent office as part of our ongoing strategy to proactively strengthen the patent portfolio covering our Levulan PDT technology.” Doman continued, “The successful affirmation of our existing patent claims and the addition of eight new claims, along with the recent issuance of US Patent No. 7,723,910 further validates our intellectual property protection strategy for Levulan PDT.”

AKs are rough-textured, dry, scaly patches on the skin caused by excessive exposure to ultraviolet light, such as sunlight. They occur most frequently on sun exposed areas such as the face, scalp, ears, neck, hands and arms. They form on the outermost layer of skin and they can range in colour from skin toned to reddish brown. They can also range in size from as small as a pinhead to larger than a quarter. AKs are the most frequently diagnosed skin disease by US dermatologists with over 5M treatment visits per year.

DUSA Pharmaceuticals, Inc. is an integrated dermatology pharmaceutical company focused primarily on the development and marketing of its Levulan PDT technology platform, and other dermatology products.