Results of photoprovocation and field studies on the efficacy of a novel topically applied antioxidant in polymorphous light eruption

BACKGROUND

UVA-induced photooxidation is considered to play an essential role in the pathogenesis of polymorphous light eruption (PLE), and topical pretreatment of skin with alpha-glucosylrutin (AGR), a potent plant-derived antioxidant, has been shown to significantly suppress photoprovoked PLE eruption.

AIM

In order to further elucidate the optimum pretreatment regimen and to investigate the efficacy and skin compatibility of topical preparations containing AGR under field conditions, two controlled clinical studies were conducted in PLE patients.

METHODS

In the first study, photoprovocation of PLE was performed in 20 patients, using UVA irradiation (4 x 60-100 J/cm(2)), applied to four test sites at the individual areas of predilection. One site served as an untreated control. The remaining three sites received treatment with a SPF 15 sunscreen containing 0.25% AGR (Eucerin Gel Cream Phase 2) 30 minutes before irradiation. Two of these sites were additionally pretreated with the corresponding AGR-containing vehicle (Eucerin Gel Cream Phase 1) twice daily for 3 and 7 days, respectively. The second study was conducted as a controlled in-use-test in patients with PLE (n = 27) or acne aestivalis (n = 3), who had suffered from the disease during their last year's vacation. They were educated to apply the pre-sun preparation to the formerly affected skin areas twice daily for 1 week before their planned vacation and to use the SPF 15 sunscreen 30 minutes before each vacation sun exposure. Symptoms were recorded in patients' diaries throughout the vacation and documented by a physician after their return.

RESULTS

In the first study, protection of skin with the SPF 15 sunscreen alone led to a significant prevention of PLE symptoms, especially itch, compared with the control area. Pretreatment further reduced the severity of PLE significantly and led to total prevention in 19 patients. In the second study, whereas 92.6% had reported severe and 7.4% mild PLE in the last year, there were currently only 7.4% severe cases, with 25.9% mild and 29.6% questionable cases; 37% had no symptoms at all. Also, two out of three acne aestivalis patients had diminished symptoms after treatment.

CONCLUSION

The results confirm the prophylactic efficacy of the antioxidant AGR in PLE, applied as SPF 15 sunscreen alone or additionally to pretreatment with a corresponding pre-sun preparation, and also show an effect in acne aestivalis patients.

Efficacy of urea therapy in children with ichthyosis. A multicenter randomized, placebo-controlled, double-blind, semilateral study

BACKGROUND

Ichthyoses are genetic disorders of keratinization which are uncomfortable due to their conspicuous scaling, itching and cosmetic problems. Especially in childhood, ichthyoses can lead to social discrimination and psychological problems. Efficient therapies are necessary which are safe and well tolerated.

OBJECTIVE

The aim of the study was to investigate the keratolytic and moisturizing properties as well as the tolerance of a new urea lotion when applied to hyperkeratotic and ichthyotic skin in childhood.

METHODS

The study was conducted as a multicenter, randomized, placebo-controlled, double-blind, semilateral investigation. Sixty children between 1 and 16 years treated one side of the most affected extremity with Laceran 10% urea lotion for 8 weeks. On the other side the urea-free Laceran lotion base was given. On each side of the body a control area was left untreated. The investigators evaluated the global severity of ichthyotic symptoms with the help of a visual analogue scale.

RESULTS

The analysis of the global estimation of severity of ichthyosis showed improvements being stronger in the body areas treated with Laceran 10% urea lotion (from 4.8 to 2.0 points) than in the areas treated with the urea-free Laceran lotion base (from 4.8 to 2.5 points). The response rates were 65% after 4 weeks and 78% after 8 weeks for Laceran 10% urea lotion, 50% after 4 weeks and 72% after 8 weeks for the urea-free Laceran lotion base.

CONCLUSION

It can be ascertained that Laceran 10% urea lotion has a strong positive effect on generalized ichthyotic keratinization disorders.

Anti-inflammatory effect of hamamelis lotion in a UVB erythema test

BACKGROUND

Although Hamamelis virginiana has long been used in the traditional treatment of skin diseases, there are few controlled clinical studies defining the extent of its anti-inflammatory action.

OBJECTIVE

The anti-inflammatory efficacy of pH5 Eucerin aftersun lotion with 10% hamamelis distillate, the vehicle and a prior aftersun formulation were tested in 30 healthy volunteers using a modified UVB erythema test as model of inflammation.

METHODS

Four UVB doses ranging from 1 to 2 MED were evaluated in each subject. Test fields on the back were treated occlusively for 48 h following irradiation. Chromametry and visual scoring were used to determine the degree of erythema in the treated fields and an untreated, irradiated control field 7, 24 and 48 h after irradiation.

RESULTS

Erythema suppression ranged from approximately 20% of 7 h to 27% at 48 h in the hamamelis fields. A suppression of 11-15% was recorded in the fields treated with the other lotions. Significant differences were noted between hamamelis and these lotions.

CONCLUSION

These data provide evidence for an anti-inflammatory action of the aftersun lotion with 10% hamamelis and support the usefulness of the UVB erythema test with multiple UV doses for the testing of nonsteroidal anti-inflammatory agents.

Effects of topically applied antioxidants in experimentally provoked polymorphous light eruption

BACKGROUND

Polymorphous light eruption (PLE) is the most common photodermatosis, with a prevalence of 10-20% in Western European countries and in the USA. Only few preventive measures for PLE exist, while its etiology and pathogenesis are still elusive. Recent theories on pathogenesis discuss the possible influence of oxidative stress.

OBJECTIVE

The presented randomized, placebo-controlled, double-blind study examines for the first time the protective effect of 3 different topically applied antioxidative preparations in experimentally photo-induced PLE.

METHOD

30 patients with a history of PLE underwent photoprovocation after having had applied 3 different formulations with antioxidants and one formulation with the vehicle only to the extensor surface of their upper arms, representing the individual site of predilection, twice daily for 1 week prior to and during the consecutive week of photoprovocation. The antioxidants used were combinations of different concentrations of alpha-glycosylrutin, ferulic acid and tocopheryl acetate.

RESULTS

Evaluation after the 4th photoprovocation revealed that the development and severity of PLE and concomitant pruritus were significantly reduced by the application of distinct combinations of antioxidants.

CONCLUSION

The results offer a new insight into possible pathomechanisms of PLE and suggest a new approach for preventive and therapeutic measures.