Patent attributes
The invention provides the use of a photosensitiser which is a derivative (e.g. an ester) of 5-aminolevulinic acid (5-ALA), or a pharmaceutically acceptable salt thereof, in the manufacture of a composition for use in methods of photodynamic therapy (PDT) on an animal, wherein said PDT comprises:(a) administering to said animal a composition comprising said photosensitiser; and(b) photoactivating said photosensitiser,and side-effects (e.g. pain and/or erythema) of said PDT are prevented or reduced by use of one or more of (i)-(iv):(i) said composition comprises said photosensitiser in a concentration of less than 10% wt (e.g. 0.5 to 8% wt),(ii) said composition is administered for less than 2 hours (e.g. 30 minutes to 90 minutes) prior to said photoactivation,(iii) said photoactivation is carried out with a light source having a fluence rate of less than 50 mW/cm2 (e.g. 5 to 40 mW/cm2),(iv) said photoactivation is carried out with sunlight.
