USE OF AMINOLEVULINIC ACID AND DERIVATIVES THEREOF
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/cm 2 (e.g. 5 to 40 mW/cm 2 ), (iv) said photoactivation is carried out with sunlight. Preferably, side effects of PDT are prevented or reduced by using (ii) or (iv) in combination with (i) and/or (ii).
1 . A method of photodynamic treatment of acne comprising:
(a) administering to an area characterized by acne on a patient in need of such treatment a composition comprising methyl ALA ester at a concentration of 4% to less than 10% by weight of the composition, or the equivalent concentration of a pharmaceutically acceptable salt, for a period of 30 minutes to less than 2 hours, and
(b) administering photoactivating light to the area.
2 . The method of claim 1 , wherein the concentration of methyl ALA ester is 4 to 8% by weight of the composition, or the equivalent concentration of a pharmaceutically acceptable salt.
3 . The method of claim 1 , wherein the concentration of methyl ALA ester is 8% by weight of the composition, or the equivalent concentration of a pharmaceutically acceptable salt.
4 . The method of claim 1 , wherein the administered compound is methyl ALA ester hydrochloride salt.
5 . The method of claim 4 , wherein the composition is administered for a period of 30 to 90 minutes.
6 . The method of claim 1 , wherein the composition is administered for a period of 90 minutes.
7 . The method of claim 1 , wherein the concentration of methyl ALA ester is 8% by weight of the composition, or the equivalent concentration of a pharmaceutically acceptable salt and the composition is administered for a period of 90 minutes.
8 . The method of claim 7 , wherein the administered compound is methyl ALA ester hydrochloride salt.
9 . The method of claim 1 , wherein the composition is a cream.
10 . The method of claim 8 , wherein the composition is a cream
11 . The method of claim 1 , wherein the photoactivating light has a peak wavelength in the range 631 to 637 nm.
12 . The method of claim 1 , wherein the total light dosage is about 37 J/cm 2 .
13 . The method of claim 12 , wherein the photoactivating light has a fluence rate of about 68 mW/cm 2 .
14 . The method of claim 12 , wherein the photoactivating light has a fluence rate of less than 50 mW/cm 2 .
15 . The method of claim 12 , wherein the photoactivating light has a fluence rate of about 46 mW/cm 2 .
16 . The method of claim 1 , wherein the photoactivating light is provided by an LED lamp.
17 . The method of claim 8 , wherein the photoactivating light has a peak wavelength in the range 631 to 637 nm.
18 . The method of claim 8 , wherein the total light dosage is about 37 J/cm 2 .
19 . The method of claim 18 , wherein the photoactivating light has a fluence rate of about 68 mW/cm 2 .
20 . The method of claim 18 , wherein the photoactivating light has a fluence rate of about 46 mW/cm 2 .
21 . The method of claim 8 , wherein the photoactivating light is provided by an LED lamp.
22 . The method of claim 1 , wherein the photoactivating light is provided by an LED lamp, has a peak wavelength in the range 631 to 637 nm, has a fluence rate of about 68 mW/cm 2 or 46 mW/cm 2 and the total light dose is about 37 J/cm 2 .
23 . The method of claim 8 , wherein the photoactivating light is provided by an LED lamp, has a peak wavelength in the range 631 to 637 nm, has a fluence rate of about 68 mW/cm 2 or 46 mW/cm 2 and the total light dose is about 37 J/cm 2 .
24 . The method of claim 1 , wherein acne is inflammatory acne.
25 . The method of claim 1 , wherein acne is acne vulgaris.
26 . The method of claim 1 , wherein acne is severe to moderate acne.
27 . The method of claim 8 , wherein acne is severe to moderate acne.
29 . The method of claim 1 , wherein the composition is removed prior to administering photoactivating light to the affected area.
30 . The method of claim 1 , wherein the composition is administered under occlusion.