LIPOSOMAL TRETINOIN FOR UNCOMPLICATED ACNE-VULGARIS

Frequently occurring skin irritancy and flare-up reactions impede the use of topical tretinoin for acne vulgaris due to poor patient complia nce. Liposome encapsulation improves penetration into the skin and loc al tolerability in animals. We investigated efficacy and local tolerab ility of liposomal tretinoin in man. In a double-blind study 20 patien ts with uncomplicated acne vulgaris received liposomal tretinoin (0.01 %) on one side of the body and a commercial gel preparation with eithe r 0.025% or 0.05% on the other once daily for 10 weeks. Comedones and papules/pustules were counted every 2 (-4) weeks. Then also redness, s caling, and burning were rated according to a four-point scale. Moreov er, the patients noted skin irritancy in a diary on a daily base. With conventional tretinoin the gels were equally efficacious and equally well tolerated. Liposomal tretinoin also appeared equipotent to the re ference gels. There may even have been a slightly more rapid clearing of comedones following the liposome preparation. With respect to skin irritancy, however, liposomal tretinoin was superior. As rated by the patients, liposome encapsulated tretinoin induced less burning (mean c umulative score 2.7 +/- 1.2) than the 0.025% gel (16.1 +/- 7.1) and th e 0.05% gel (9.7 +/- 4.1) gel and less erythema (1.8 +/- 0.7) than the 0.025% gel (11.4 +/- 3.8; (P < 0.05). Liposomal tretinoin was also be tter tolerated according to the rating by the investigator. Liposomal encapsulation of tretinoin allows reduction of the concentration of th e active agent without a decline in efficacy for acne vulgaris. Since local tolerability is thus increased, liposomal tretinoin should favor the acceptance of this treatment by the patient.