Biodistribution of protoporphyrin IX in female genital erosive lichen planus after topical application of hexaminolevulinate

• Published in: Photodiagnosis and photodynamic therapy Vol. 11; no. 2; pp. 113 - 117
• Main Authors: Helgesen, Anne Lise Ording, Gjersvik, Petter, Peng, Qian, Vasovic, Vlada, Pripp, Are Hugo, Jebsen, Peter, Tanbo, Tom, Warloe, Trond
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.06.2014
• Subjects: Administration, Topical; Aminolevulinic Acid - administration & dosage; Aminolevulinic Acid - analogs & derivatives; Aminolevulinic Acid - pharmacokinetics; Dose-Response Relationship, Drug; Erosive lichen planus; Female; Genital; Genital Diseases, Female - drug therapy; Genital Diseases, Female - metabolism; Genital Diseases, Female - pathology; Hematology, Oncology and Palliative Medicine; Hexylaminolevulinate; Humans; Internal Medicine; Lichen Planus - drug therapy; Lichen Planus - metabolism; Lichen Planus - pathology; Metabolic Clearance Rate - drug effects; Photochemotherapy - methods; Photosensitizing Agents - administration & dosage; Photosensitizing Agents - pharmacokinetics; Protoporphyrins - metabolism; Tissue Distribution - drug effects; Treatment Outcome; Genital; Erosive lichen planus; Hexylaminolevulinate
• ISSN: 1572-1000; 1873-1597
• DOI: 10.1016/j.pdpdt.2014.01.005

Summary Genital erosive lichen planus (GELP) is a chronic inflammatory disease, in women characterized by painful vulvar and vaginal erosions. To prepare for a clinical trial on photodynamic treatment (PDT), we applied hexyl 5-aminolevulinate hydrochloride (HAL) in clinically normal and affected mucosa in 12 women with GELP using two different doses (6.25 or 50 mg/ml). Biopsies were taken after 30 min and 3 h. The biodistribution of HAL, measured as photoactive protoporphyrin IX (PpIX), was studied using non-invasive superficial fluorescence measurements and microscopic fluorescence photometry. More PpIX was detected after application of 12.5 mg HAL than after 100 mg, with large inter-individual variations. PpIX levels after 3 h were overall higher than after 30 min. PpIX fluorescence was not detected in skin distant to the genital area. In conclusion, 6.25 mg/ml HAL applied for 3 h seems adequate for HAL absorption and conversion to PpIX in submucosal inflammatory and epithelial cells and can be used in a PDT trial of GELP.