Disappointing results and low tolerability of photodynamic therapy with topical 5-aminolaevulinic acid in psoriasis. A randomized, double-blind phase I/II study.
BACKGROUND
Based on good results in the treatment of superficial skin tumours, since the early 1990s topical photodynamic therapy with aminolaevulinic acid (ALA PDT) has been used for disseminated, inflammatory dermatoses including psoriasis. However, there is still a lack of well-documented trials.


OBJECTIVE
A prospective randomized, double-blind phase I/II intrapatient comparison study was conducted in 12 patients to investigate whether topical ALA PDT is an effective treatment for chronic plaque-type psoriasis.


METHODS
In each patient three psoriatic plaques were randomly treated with a light dose of 20 J/cm(2) and 0.1%, 1% and 5% ALA, respectively. Treatment was conducted twice a week until complete clearance or for a maximum of 12 irradiations. Therapeutic efficacy was assessed by weekly determination of the psoriasis severity index (PSI).


RESULTS
The mean percentage improvement was 37.5%, 45.6% and 51.2% in the 0.1%, 1% and 5% ALA-treated groups, respectively. Irradiation had to be interrupted several times because of severe burning and pain sensation.


CONCLUSIONS
Topical ALA PDT did not prove to be an appropriate treatment option for plaque-type psoriasis due to disappointing clinical efficacy, the time-consuming treatment procedure and its unfavourable adverse event profile.
Schleyer
V
V
Department of Dermatology, University of Regensburg, Regensburg, Germany.
Radakovic-Fijan
S
S
Karrer
S
S
Zwingers
T
T
Tanew
A
A
Landthaler
M
M
Szeimies
R M
RM
D000287:Administration, Topical; D000328:Adult; D000622:Aminolevulinic Acid / Q000008:administration & dosage* / Q000009:adverse effects; D002908:Chronic Disease; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008297:Male; D010778:Photochemotherapy / Q000009:adverse effects; D017319:Photosensitizing Agents / Q000008:administration & dosage* / Q000009:adverse effects; D011565:Psoriasis / Q000188:drug therapy* / Q000473:pathology; D011879:Radiotherapy Dosage
D017319:Photosensitizing Agents; D000622:Aminolevulinic Acid