Pulse photodynamic treatment of skin conditions

Abstract

A pulse photodynamic therapy (or pulse PDT) treatment of skin complaints is described herein. The skin complaint being treated can be actinic keratosis (AK) or a basal cell carcinoma (BCC).

1 . A method of treating a skin condition in an animal the method comprising adminisering a photosensitizer to the animal skin, wherein the photosensitizer treats the skin condition with photodynamic therapy (PDT), and wherein the photosensitizer is applied to the skin of the animal for a short period of time, and the skin condition is actinic keratosis or basal cell carcinoma. 
     
     
         2 . The method according to  claim 1 , wherein the method reduces side effects associated with PDT. 
     
     
         3 . The method according to  claim 1 , further comprising applying the photosensitizer to the skin of the animal for a period of from 5 minutes to 120 minutes. 
     
     
         4 . The method according to  claim 1 , wherein the PDT includes a photoactivation achieved by artificial or natural light source. 
     
     
         5 . The method according to  claim 1 , wherein the PDT comprises:
 a) administering to the animal a composition comprising the photosensitizer for a duration of from 5 minutes to 120 minutes; and   b) photoactivating the photosensitizer for a duration of from 1 minute to 15 minutes with artificial light or from 0.5 hour to 3 hours with natural light.   
     
     
         6 . The method according to  claim 5 , wherein the PDT comprises:
 a) administering to the animal a composition comprising the photosensitizer for a duration of from 15 minutes to 60 minutes; and   b) photoactivating the photosensitizer for a duration of from 5 minutes to 10 minutes with artificial light or from 0.5 hour to 2 hours with natural light.   
     
     
         7 . The method according to  claim 6 , wherein PDT comprises:
 a) administering to the animal a composition comprising the photosensitizer for a duration of 30 minutes; and   b) removing the photosensitizer; and   c) photoactivating the photosensitizer 2.5 hours later for a duration of 9 minutes with artificial light or of at least 2 hours with natural light.   
     
     
         8 . The method according to  claim 1 , wherein the photosensitizer is selected from the group consisting of 5-ALA, 5-ALA derivatives, 5-MAL, 5-MAL derivatives, and compounds covered by general formula I:
   R 2   2 N—CH 2 COCH 2 —CH 2 CO—OR 1    (I)
   wherein:   R 1  represents a substituted or unsubstituted straight, branched or cyclic alkyl group; and each R 2  independently represents a hydrogen atom or an optionally substituted alkyl group; and pharmaceutically acceptable salts thereof.   
     
     
         9 . The method according to  claim 1 , wherein the photosensitizer is 5-ALA or 5-methyl ALA ester. 
     
     
         10 . The method according to  claim 1 , wherein administering the photosensitizer to the animal is carried out with or without occlusion. 
     
     
         11 . The method according to  claim 1 , wherein the photosensitizer is used in combination with a glucocorticosteroid. 
     
     
         12 . The method according to  claim 3 , wherein the period of time is from 15 minutes to 60 minutes. 
     
     
         13 . The method according to  claim 4 , wherein the artificial or natural light source is a LED or sunlight. 
     
     
         14 . The method according to  claim 8 , wherein the alkyl group is a substituted or unsubstituted straight-chained alkyl group. 
     
     
         15 . The method according to  claim 10 , wherein the administration of the photosensitizer is carried out with occlusion.