According to a study, researchers examined that the treatment with Rmucosa was associated with significant decreases in measures of disease severity, topical steroid requirement, and Saureus burden. Topical treatment with live Roseomonas mucosaa bacterium naturally present on the skin was safe for adults and children with atopic dermatitis (eczema) and was associated with reduced disease severity. The study was published in JCI Insight.

Preclinical work in a mouse model of atopic dermatitis had suggested that R. mucosa strains collected from healthy skin can relieve disease symptoms.

Atopic dermatitis is an inflammatory skin disease that can make skin dry and itchy, cause rashes and lead to skin infections. The disease is linked to an increased risk of developing asthma, hay fever, and food allergy. Atopic dermatitis is common in children and sometimes resolves on its own, but it also can persist into or develop during adulthood.

"Living with atopic dermatitis can be physically and emotionally challenging. While treatment can help manage the symptoms, currently available therapies can be time-consuming requiring multiple daily applications and costly. New, inexpensive therapies that require less frequent application are needed to expand the options available for atopic dermatitis treatment.

The cause of atopic dermatitis is unknown, but studies suggest that the skin microbiome, the community of bacteria and other microbes living on the skin plays a key role. Scientists have known that people with atopic dermatitis tend to have large populations of Staphylococcus aureus bacteria on their skin. These bacteria can cause skin infections and trigger immune responses that increase inflammation and worsen symptoms.

Bacterial Treatment

By applying bacteria from a healthy source to the skin of people with atopic dermatitis, we aim to alter the skin microbiome in a way that will relieve symptoms and free people from the burden of constant treatment.

If future clinical studies demonstrate that this strategy is effective, they hope our work will lead to the development of new, low-cost atopic dermatitis therapies that do not require daily application.

The researchers first tested the experimental treatment in 10 adult volunteers with atopic dermatitis. Twice a week for six weeks, the volunteers sprayed a solution of sugar water containing increasing doses of live R. mucosa onto their inner elbows and one additional skin area of their choice. Participants were instructed to continue their normal eczema treatments, including topical steroids and other medications.

Participants did not report any adverse reactions or complications. Most participants experienced improvements in their atopic dermatitis, and four weeks after stopping the bacteria therapy, some reported needing fewer topical steroids.

To better understand factors that may contribute to imbalances in the bacteria on the skin, the scientists also investigated whether chemicals produced by R. mucosa or present in certain skin products may be associated with atopic dermatitis. They found that strains of R. mucosa from people with atopic dermatitis produced skin irritants, while strains isolated from healthy skin produced chemicals that may enhance the skin's barrier and help regulate the immune system.

Final results from the ongoing study at NIH will provide the foundation for larger trials to evaluate the efficacy of this novel investigational therapy, as well as to better understand the role of R. mucosa in atopic dermatitis. NIH has exclusively licensed the technology to Forte Biosciences to advance this potential new therapy through further clinical development.