Evaluation of novel cosmetic shampoo formulations against Malassezia species: Preliminary results of anti-dandruff shampoo formulations.

Malassezia species are common, clinically relevant, and lipid-dependent yeasts of humans. They are also the leading causes of the dandruff problem of humans, and the azoles are used primarily in their topical and systemic treatment. Resistance to azoles is an emerging problem among Malassezia sp., which indicates the need of new drug assessments that will be effective against dandruff and limit the use of azoles and other agents in treatment. Among them, the efficacy of various combinations of piroctone olamine and climbazole against Malassezia sp. is highly important. Here, we assessed the efficacies of various piroctone olamine and climbazole formulations against Malassezia sp. in comparison with ketoconazole. A total of nine formulations were included in the study, where each formulation was prepared from different concentrations of piroctone olamine and climbazole and both. All formulations contained the same ingredients as water, surfactants, hair conditioning agents, and preservatives. Malassezia furfur CBS1878, Malassezia globosa CBS7874, and Malassezia sympodialis CBS9570 were tested for antifungal susceptibility of each formulation by agar diffusion method. Sizes of the inhibition zones were compared with standard medical shampoo containing 2% ketoconazole, and the data were analyzed by Dunnett's multiple-comparison test. For all Malassezia sp. strains, climbazole 0.5% and piroctone olamine/climbazole (0.1%/0.1% and 0.1%/0.5%) combinations were found to have the same effect as the medical shampoo containing 2% ketoconazole. Piroctone olamine/climbazole 1.0%/0.1% formulation showed the same efficacy as 2% ketoconazole on M. furfur and M. sympodialis, while 0.1%/0.5% formulation to only M. furfur. For M. globosa, none of the formulations tested were as effective as ketoconazole. The species distribution of Malassezia sp. varies depending on the anatomical location on the host. According to the results of this study, climbazole and piroctone olamine combinations seem to be promising options against the dandruff problem with their high antifungal/anti dandruff efficacy.

Ergin Ç ，Kurt Ö ，Türkoğlu M ，Sevinç H ，Akbaba G ... -  《-》

Efficacy of a piroctone olamine/climbazol shampoo in comparison with a zinc pyrithione shampoo in subjects with moderate to severe dandruff.

Dandruff is a chronic scalp disorder characterized by scaling and itching. A successful anti-dandruff shampoo not only has to provide superior anti-dandruff relief to ensure patient compliance. It also needs to offer excellent cosmetic and hair conditioning benefits at the same time. In this study, the efficacy of a shampoo containing 0.5% piroctone olamine and 0.45% climbazole (shampoo 1) was compared with a widely available commercial shampoo containing 1% zinc pyrithione (shampoo 2). In vitro studies investigating the anti-mycotic efficacy of a combination of 0.5% piroctone olamine and 0.45% climbazole as well as 1% zinc pyrithione were performed. To study substantivity, pig skin punches were used as a model system and a test of wet combability was performed to characterize combing ease. In vivo home-in-use studies were carried out to determine the efficacy of both shampoos to improve scalp condition and reduce itching in subjects suffering from moderate to severe dandruff. Results demonstrated a comparable anti-fungal effectiveness for 0.5% piroctone olamine plus 0.45% climbazole and 1% zinc pyrithione, respectively. Shampoo 1 showed a significantly higher anti-mycotics substantivity compared to shampoo 2. After treatment with shampoo 1, the wet combing force was significantly reduced compared with shampoo 2, suggesting a better combability following the use of shampoo 1. In an in vivo split head design study, shampoo 1 was shown to be equally effective in reducing the amount of dandruff on the scalp compared with shampoo 2. The approval rate of volunteers regarding the question 'The use of this shampoo decreases the itching of my scalp?' after a 4-week treatment with shampoo 1 equaled 90%. Overall, the shampoo formulation with 0.5% piroctone olamine and 0.45% climbazole effectively reduces the amount of dandruff and, at the same time, provides hair conditioning advantages.

Schmidt-Rose T ，Braren S ，Fölster H ，Hillemann T ，Oltrogge B ，Philipp P ，Weets G ，Fey S ... -  《-》

In vitro efficacy of antifungal agents alone and in shampoo formulation against dandruff-associated Malassezia spp. and Staphylococcus spp.

Dandruff is a complex skin condition characterized by unpleasant itching and flaking of the scalp. It is primarily attributed to the over colonization of Malassezia yeasts such as Malassezia globosa and Malassezia restricta. Some studies also suggest the involvement of staphylococci bacteria in dandruff disease pathogenesis. We aimed to access the effectiveness of anti-dandruff treatments by determining the efficacy of the active antifungal agents alone or in commercial shampoo formulations against Malassezia and Staphylococcus. The minimum inhibitory concentrations of three anti-dandruff shampoo antifungals (zinc pyrithione, ketoconazole and ciclopirox) and the witch hazel extract, hamamelitannin were tested against commensal Malassezia and Staphylococcus species using broth microdilution methods. In experiments simulating shampoo exposure and washing conditions on the scalp, we also tested the ability of the above agents in shampoo formulation (Head and Shoulders® (H&S), Ketomed® , Sebiprox® , Erol Healthcare Hair Shampoo® respectively) along with a generic over-the-shelf shampoo to inhibit microbial growth. Ketomed® and H&S shampoo were the most effective treatments against Malassezia in in vitro assays and washing simulation experiments. Erol Healthcare Hair Shampoo® was less effective against Malassezia as it required a longer contact time to achieve growth inhibition for some species. Sebiprox® showed variable efficacy in washing and contact time experiments whereas the generic over-the-shelf shampoo was the least effective in inhibiting Malassezia and Staphylococcus growth. From these findings, it is reasonable that patients with dandruff may benefit from applying specific antifungal shampoo although results may vary with microbial species, time of contact and shampoo formulation components.

Leong C ，Schmid B ，Buttafuoco A ，Glatz M ，Bosshard PP ... -  《-》

[How I treat … dandruff using a shampoo with a sulfate-free tensio-active].

Reygagne P ，Piérard GE ，Loussouarn G ，Le Nôtre N ，Ziane S ... -  《-》

Scalp microbiome composition changes and pathway evaluations due to effective treatment with Piroctone Olamine shampoo.

To characterize the scalp microbial composition, function, and connection to dandruff severity using a metagenomics approach and to understand the impact of a Piroctone Olamine containing anti-dandruff shampoo on the scalp microbiome. Shotgun metagenomics was used to characterize the composition of the scalp microbiomes from 94 subjects with and without clinically defined dandruff. Furthermore, the microbiome of the scalps of 100 dandruff sufferers before and after 3 weeks of treatment with either control or anti-dandruff shampoo containing 0.5% Piroctone Olamine (PO) was characterized and compared to identify microorganisms associated with the dandruff condition and the associated pathways and processes that may contribute to PO's effect on scalp microbiome. A higher relative abundance of Malassezia restricta and Staphylococcus capitis and a lower abundance of Cutibacterium acnes were associated with the dandruff scalps relative to the no-dandruff scalps. A 3-week PO shampoo treatment reduced the relative abundance of Malassezia species and Staphylococcus capitis and increased the relative abundance of Cutibacterium acnes. This change to the scalp microbiome composition is consistent with a return to a healthy no-dandruff microbiome and improved clinical signs and symptoms as measured by adherent scalp flaking score (ASFS) compared with the control shampoo. Functional genomics analysis showed that the PO shampoo treatment reduced oxidative stress-associated genes and decreased the abundance of protease, urease, and lipase genes. These changes correlated positively to improvements in dandruff severity. PO treatment favourably shifted scalp microbiomes in dandruff subjects toward the no-dandruff state. Our results suggest that part of the aetiology of dandruff can be attributed to dysbiosis of the scalp microbiome. PO treatment can restore a healthier microbiome, reducing oxidative stress and promoting better scalp health.

Hu P ，Henry J ，Tiesman JP ，Parlov M ，Bacon R ，Charbonneau D ，Venkataraman A ，Locker KCS ，Krigbaum H ，Schwartz J ... -  《-》