Photochemotherapeutic method using 5-aminolevulinic acid and other precursors of endogenous porphyrins

Abstract

Methods of detecting and treating rapidly growing exogenous cells, such as Protista, or parasites, that preferentially accumulate a photoactivatable porphyrin in which 5-aminolevulinic acid or precursor thereof is administered to the patient, or contacted to the exogenous cells, in an amount sufficient to induce synthesis fluorescence and/or photosensitizing concentrations of a protoporphyrin IX in the exogenous cells, followed by exposure of the exogenous cells to light of photoactivating wavelengths.

1 . A method for treating in a human patient a non-malignant lesion of the esophagus that preferentially accumulates a photoactivatable porphyrin, comprising administering to said human patient in need thereof an effective amount of a precursor of protoporphyrin IX thereby accumulating therapeutic levels of said protoporphyrin IX, and thereafter exposing said lesion to light capable of photoactivating said protoporphyrin IX.  
     
     
         2 . A method for detecting in a human patient a non-malignant lesion of the esophagus that preferentially accumulates a photoactivatable porphyrin, comprising administering to said human patient in need thereof an effective amount of a precursor of protoporphyrin IX thereby accumulating therapeutic levels of said protoporphyrin IX, and thereafter exposing said lesion to light capable of photoactivating said protoporphyrin IX.  
     
     
         3 . The method of  claim 1  or  2 , wherein said precursor is 5-amino levulinic acid.  
     
     
         4 . The method of  claim 1  or  2 , wherein said wavelength of light is 350-640 nm.  
     
     
         5 . The method of  claim 1  or  2 , wherein said wavelength of light is 600-700 nm.  
     
     
         6 . The method of  claim 1  or  2 , wherein said method comprises treating or detecting the mucosa of the esophagus.  
     
     
         7 . The method of  claim 1  or  2 , wherein said method comprises treating a premalignant condition in which the normal stratified squamous epithelium of the esophagus is replaced by a metaplastic columnar epithelium.  
     
     
         8 . A photosensitizing treatment method for treating non-malignant lesions of the esophagus in a human patient comprising 
 (a) administering an agent which is not a photosensitizer but induces the synthesis of protoporphyrin IX in vivo and then    (b) exposing the lesions of the esophagus to a wavelength of light within the photoactivating spectrum of protoporphyrin IX.    
     
     
         9 . The method of  claim 8 , wherein said agent induces synthesis of protoporphyrin IX in the heme biosynthetic pathway.  
     
     
         10 . The method of  claim 8 , wherein said agent is a precursor of protoporphyrin IX.  
     
     
         11 . The method of  claim 8 , wherein said wavelength of light is 350-640 nm.  
     
     
         12 . The method of  claim 8 , wherein said wavelength of light is 600-700 nm.  
     
     
         13 . The method of  claim 8 , wherein said agent is 5-amino levulinic acid.  
     
     
         14 . The method of  claim 1  or  8 , wherein said agent is administered topically.  
     
     
         15 . The method of  claim 1  or  8 , wherein said agent is administered systemically.  
     
     
         16 . The method of  claim 1  or  8 , wherein said light is generated from an artificial light source.  
     
     
         17 . The method of  claim 1  or  8 , wherein said light is only within the absorption spectrum of protoporphyrin IX.  
     
     
         18 . The method of  claim 1  or  8 , wherein said photoactivating light is limited to the red and blue regions of the spectrum.  
     
     
         19 . The method of  claim 8 , wherein said method comprises treatment of the mucosa of the esophagus.  
     
     
         20 . The method of  claim 8 , wherein said method comprises treatment of a premalignant condition in which the normal stratified squamous epithelium of the esophagus is replaced by a metaplastic columnar epithelium.