Combination of 5% cysteamine and 4% nicotinamide in melasma: Efficacy, tolerability, and safety.

BACKGROUND: Melasma is a chronic dermatosis that impacts the patient's quality of life and can present considerable challenges in terms of effective treatment. OBJECTIVE: To evaluate the effectiveness, tolerability, and safety of 5% cysteamine combined with 4% nicotinamide in female subjects with melasma. METHODS: This single-center, single-arm, prospective, open-label study evaluated patients with melasma using a combination cream of 5% cysteamine and 4% nicotinamide in a progressive regimen (60 min in the first month, 120 min in the second month, and 180 min in the third month). RESULTS: Overall, 35 treated subjects exhibited reduced modified Melasma Area and Severity Index (mMASI) (p < 0.001) and decreased MelasQoL scores (p < 0.001), accompanied by improved brightness, luminosity, homogeneity, and spot intensity (p < 0.001). Photographic and colorimetric analysis revealed smaller spots and improved homogeneity. LIMITATIONS: Adherence to progressive daily treatment could not be evaluated long-term. CONCLUSION: A combination cream comprising 5% cysteamine and 4% nicotinamide was effective, tolerable, and safe for treating melasma.

Preclinical and clinical studies to evaluate cutaneous biodistribution, safety and efficacy of UV filters encapsulated in mesoporous silica SBA-15.

Innovative technologies have been designed to improve efficacy and safety of chemical UV filters. Encapsulation can enhance efficacy and reduce transdermal permeation and systemic exposure. The aims of this work were (i) to determine the cutaneous biodistribution of avobenzone (AVO), oxybenzone (OXY), and octyl methoxycinnamate (OMC) incorporated in mesoporous silica SBA-15 and (ii) to perform preclinical (in vitro) and (iii) clinical safety studies to demonstrate their innocuity and to evaluate sun protection factor (SPF) in humans. Skin penetration studies showed that deposition of OXY and AVO in porcine and human skin after application of stick formulation with incorporated filters (stick incorporated filters) was significantly lower than from a marketed (non-encapsulated) stick. Cutaneous deposition and transdermal permeation of OXY in and across human skin were 3.8-and 13.4- fold lower, respectively, after application of stick entrapped filters. Biodistribution results showed that encapsulation in SBA-15 decreased AVO and OXY penetration reaching porcine and human dermis. Greater deposition (and permeation) of OXY in porcine skin than in human skin, pointed to the role of follicular transport. Stick incorporated filters had good biocompatibility in vivo and safety profiles, even under sun-exposed conditions. Entrapment of UV filters improved the SPF by 26% and produced the same SPF profile as a marketed stick. Overall, the results showed that SBA-15 enabled safety and efficacy of UV filters to be increased.

Reações adversas ocasionadas por uso de protetores solares / Adverse reactions caused by the use of sunscreens

Introdução: O excesso de exposição da pele ao sol pode ocasionar o fotoenvelhecimento e favorecer o surgimento de neoplasias malignas na pele. Assim, os protetores solares tornaram- se amplamente utilizados para a prevenção de danos solares, a curto e longo prazo. Podem ocasionalmente provocar reações adversas em crianças e adultos. Objetivo: Analisar a frequencia e os tipos de reações adversas ocasionadas por protetores solares em adultos e crianças. Métodos: Análise de banco de dados sobre estudos clínicos não invasivos in vivo, em face e corpo, realizados em instituto de pesquisa clínica, em São Paulo, Brasil. Resultados: Foram avaliados de janeiro de 2014 a dezembro de 2015, dados de 2263 adultos e 523 crianças. 13,92% dos adultos e 4,44% das crianças apresentaram algum tipo de reação adversa leve. Conclusões: Observou-se que os protetores solares são eficazes na prevenção do fotoenvelhecimento e câncer de pele. As formulações cosméticas com filtros solares podem ocasionar reações adversas com baixa prevalência.

Introduction: Overexposure of the skin to the sunlight can cause photoaging and promote the emergence of malignant neoplasms. Sunscreens are used to prevent these alterations and may occasionally cause adverse reactions in children and adults. Objective: To analyze the frequency and types of adverse reactions caused by sunscreens in adults and children. Methods: Data analysis of in vivo, non-invasive clinical studies performed at a clinical research institute. Results: Data from 2,263 adults and 523 children were evaluated, with 13.92% and 4.44%, respectively, presenting some type of reaction. Conclusions: Sunscreens are effective in preventing photoaging and skin cancer. Cosmetic formulations containing sunscreens may cause adverse reactions with low prevalence.

Combination of retinyl palmitate and UV-filters: phototoxic risk assessment based on photostability and in vitro and in vivo phototoxicity assays.

This study aimed to assess the phototoxic potential of combined UV-filters and retinyl palmitate (RP) in the presence or not of bemotrizinol (BMTZ), employing photostability and in vitro and in vivo phototoxicity assays. The formulations tested contained octocrylene (OCT), octyl methoxycinnamate (OMC), benzophenone-3 (BZP-3) and RP (photostable) or octocrylene (OCT), octyl methoxycinnamate (OMC), avobenzone (AVO) and RP (less photostable). Both formulations were supplemented with bemotrizinol. Photostability was evaluated by exposing, or not, formulations spread on a glass plate to UVA/UVB irradiation. The resulting products were quantified by HPLC analysis. In vitro phototoxicity of UV-filters and combinations were evaluated using 3T3 viable monolayer fibroblast cultures submitted, or not, to irradiation according to OECD TG 432. In vivo photoallergy and photoxicity were assessed by clinical studies (photopatch test). Photostability assays showed that UV-filter bemotrizinol was a better photostabilizer for RP/benzophenone-3 than for RP/avobenzone. The in vitro phototoxicity of the combination RP/avobenzone was reduced by bemotrizinol. Clinical studies did not indicate phototoxic or photoallergenic potentials in all formulations tested. It is concluded that the 3T3 NRU phototoxicity test may be considered a supplementary assay in formulation developments, since it can detect chemically unstable and potentially phototoxic combinations. However, extrapolation of in vitro positive results to human photopatch tests may be performed only to a limited extent.

Safety assessment of cosmetic products, with emphasis on the ocular area: regulatory aspects and validation processes

Before marketing a cosmetic product, a series of biological assays, such as ocular irritation tests, must be conducted in order to prove that the product is safe. However, a few scientific articles mention the discussion and evolution of cosmetic products testing performed in the eyes area. The aim of this study was to review the available literature on the evolution of tests carried out with cosmetics, in the ocular area, as well as to describe the methodologies that have been used and that are currently accepted. In Brazil, tests performed on animals are still allowed. However, the international laws strongly recommend the use of alternative methods for evaluating the risk of cosmetic ingredients and products. Regulatory requirements involving the registration of these products also request safety support of them in human beings. To perform ocular tests in human beings, it is necessary to involve an ophthalmologist for conducting clinical protocols. These protocols signed by the expert physician are sent to the National Health Surveillance Agency in order to endorse the product manufacturer concerning its safety. The safety support of a cosmetic product is very important, taking into account that the consumer has free access to these products of widespread use in today's society.

Com o objetivo de comprovar que um produto cosmético é seguro, antes que este seja colocado no mercado, este deve passar por uma série de ensaios biológicos, que avaliem sua segurança, como, por exemplo, os testes de irritação ocular. Porém, poucos artigos científicos trazem a discussão e a evolução sobre os testes de produtos cosméticos realizados na área dos olhos. O objetivo desse trabalho foi realizar uma revisão bibliográfica sobre a evolução dos testes realizados com cosméticos, na região ocular, bem como descrever as metodologias que já foram utilizadas e as que são aceitas atualmente. No Brasil, são ainda permitidos testes em animais, entretanto, as legislações internacionais indicam fortemente a utilização de métodos alternativos para avaliação de risco de ingredientes e produtos cosméticos. As exigências regulatórias que envolvem o registro desses produtos solicitam também a comprovação de segurança destes produtos em serem humanos. Para a realização dos testes oculares em humanos, é necessário o envolvimento de um oftalmologista na condução de protocolos clínicos. Esses protocolos assinados pelo médico especialista são enviados à Agencia Nacional de Vigilância Sanitária, a fim de respaldar o fabricante do produto sobre a segurança do mesmo. A comprovação da segurança de um produto cosmético é bastante importante, considerando-se o livre acesso aos consumidores e o amplo uso desses produtos na sociedade atual.