Atopic dermatitis is a common form of eczema that affects millions of people in the United States. Now, a new proof-of-concept study suggests that a novel drug could relieve symptoms after just one dose.
Researchers estimate that about 16.5 million adults in the United States have atopic dermatitis.
This is a chronic condition that causes skin to become sore, dry, cracked, and irritated.
There is currently no cure for this skin condition, but doctors can help people find a treatment plan that helps reduce the severity of symptoms when they occur.
Such treatment plans include adjusting diet and lifestyle, using topical creams, and taking other forms of medication, such as immunosuppressants.
Immunosuppressants — which doctors often prescribe to people with severe forms of this condition — include ciclosporin and methotrexate, which work by dampening the body's immune response to allergens that trigger symptoms of atopic dermatitis.
Researchers are therefore on the lookout for alternative drugs that could also efficiently improve the symptoms of atopic dermatitis.
A new proof-of-concept study — led by researchers from the University of Oxford in the United Kingdom — suggests that a new drug, called "etokimab," could be an effective alternative.
Significant symptom improvements
For their new study, the researchers recruited 12 participants with atopic dermatitis. Their findings appear in the journal Science Translational Medicine, and the researchers thank AnaptysBio, a clinical stage antibody development company, for funding the small trial.
All participants received a dose of etokimab. This drug targets a signaling molecule called interleukin 33 (IL-33), which has a role in targeting immune responses.
After 29 days, 83% of those who received the treatment displayed significant improvements in physical symptoms of dermatitis, reducing their scores of disease severity by at least half.
At the end of the study period, the participants also showed a 40% reduction in the levels of a particular type of immune cell in the bloodstream. This cell is called eosinophil, and it is linked to how sensitive a person is to different allergens.
"This clinical trial is the first time we've looked at how blocking IL-33 can help [people] with atopic dermatitis, and we have found they experienced significant improvement in their symptoms after a single dose," says lead researcher Prof. Graham Ogg.
"These results are only very preliminary, and we need to be cautious," he notes, "but we're currently testing the therapy in a larger double-blind randomized trial in people with atopic dermatitis, and we look forward to seeing the results."
The ongoing trial has enlisted around 300 participants, and it aims to confirm the effectiveness of etokimab in treating atopic dermatitis.
"New antibody therapies, like etokimab, are exquisitely specific in what they target, and they have the potential to help [people] and to help us better understand disease."
Prof. Graham Ogg
Potential for other treatments
The investigators also believe that further studying the role of IL-33 in skin health could reveal whether or not etokimab might also be helpful in treating a more varied array of immune conditions.
This notion is based on a series of observations that the investigators made over the course of the small trial. They explain that during the study, they first delivered a placebo injection to the participants.
A week after that, they gave them the injection with etokimab. At 4 days following each of these two injections, the researchers performed an experiment: They injected a placebo substance into the skin of the participants' left arms, and house dust mite allergens into the skin of their right arms.
The investigators then took samples of cells and fluid from the site of these injections to analyze them.
They found that at 1 day after receiving the treatment with etokimab, the participants experienced less neutrophil activity in the spots the researchers challenged with allergens. Neutrophils, which are a type of immune cell, are involved in inflammation.
This, they argue, suggests that targeting IL-33 could actually help treat different immune conditions that involve heightened neutrophil activity.
"We've been studying the role of IL-33 in human skin for nearly 10 years, [...] with the lab work suggesting IL-33 might be a potential target for therapies. So we are pleased that in this first human trial in [people] with atopic dermatitis, we have confirmed that the IL-33 pathway appears to be a therapeutic target in its own right," says Prof. Ogg.
"Doing experimental research in humans in crucially important if we are to make advances in treatment, and in this study it was initially surprising to us that the dominant effect of etokimab was reducing neutrophil migration into the skin," he adds.
For this reason, he is "very grateful and humbled by all the [people] who've generously contributed skin and blood samples over the years to help us to understand the underlying processes that contribute to their atopic dermatitis — our research completely depends on such support."