Benralizumab for Eczema: The 194-Patient HILLIER Trial Separated Blood Counts From Skin Benefit
If a blood test shows high eosinophils, it is understandable to wonder whether an eosinophil-depleting medicine would also clear eczema. The HILLIER trial tested that idea directly with benralizumab. Its answer highlights why a laboratory response and a useful improvement in skin disease must be measured separately.
What HILLIER tested
The 2023 primary HILLIER report describes a randomized, double-blind, placebo-controlled phase 2 study of 194 patients aged 12 or older. Participants had moderate-to-severe atopic dermatitis despite background topical treatment: investigator assessment at least 3, EASI at least 16, at least 10% affected body surface area and peak itch score at least 4.
Ninety-six people received benralizumab 30 mg every four weeks and 98 received placebo. These groups included 26 and 27 adolescents, respectively. Randomization accounted for age and baseline blood eosinophils below or above 300 cells per microliter. The study planned a 16-week controlled period and a 36-week open extension but was terminated early for lack of efficacy. The published comparisons concern the controlled 16 weeks.
Skin clearance and itch did not improve versus placebo
The primary response required both clear or almost-clear skin on the investigator scale and at least a two-point improvement. The table below uses observed headcounts. The publication also reports modeled response rates; these differ slightly and should not be mixed with raw percentages.
| Week-16 outcome | Benralizumab, 96 participants | Placebo, 98 participants |
|---|---|---|
| Primary investigator response | 9 people; 9.4% | 17 people; 17.3% |
| EASI-75: at least 75% score improvement | 19; 19.8% | 24; 24.5% |
| EASI-90: at least 90% score improvement | 7; 7.3% | 15; 15.3% |
| At least four-point peak-itch improvement | 14; 14.6% | 14; 14.3% |
For the primary endpoint, the adjusted benralizumab-minus-placebo difference was −8.62 percentage points, with 95% confidence interval −17.94 to 0.71 and p=0.080. This did not demonstrate benefit. It also does not prove the two treatments equivalent: an interval crossing zero is not an equivalence test. Secondary outcomes likewise did not show significant advantages, including itch, disease scores and quality of life.
The biological target still changed substantially
Mean blood eosinophils in the active group fell from 482.3 to 40.0 cells per microliter by week 16. In the placebo group, the corresponding means were 464.4 and 354.9. A second eosinophil-related marker also declined more with benralizumab. The medicine affected its biological target; that did not translate into demonstrated clinical benefit for eczema in this trial.
This larger, longer comparison is a separate experiment from the older mepolizumab eczema study. Together they caution against selecting eczema treatment from an isolated blood count. They do not show that eosinophils have no role in any patient or that these medicines lack benefit for their approved diseases. Our dupilumab and eosinophils explanation also distinguishes a laboratory change from symptoms requiring medical assessment.
Safety and the current label require their own reading
Any adverse event occurred in 39 of 96 active-treatment participants and 40 of 98 placebo participants. Three people receiving benralizumab had serious events; investigators judged none related to the study drug. No placebo participant had a serious event, and no deaths occurred. Similar overall event percentages in a short phase 2 trial cannot establish that every important risk is the same.
The current U.S. Fasenra label lists specified severe eosinophilic asthma, EGPA and hypereosinophilic syndrome indications with their own age criteria. It does not list atopic dermatitis. Its warnings include hypersensitivity and precautions concerning steroid reduction and helminth infection. Do not discontinue an asthma medicine or change corticosteroids because an eczema trial was negative. AstraZeneca funded HILLIER and its medical-writing support.
A practical question for your next visit
Ask which finding is driving a proposed choice: uncontrolled skin inflammation, a separate eosinophilic disease, or both. Record eczema symptoms, sleep interruption and interference with work or exercise rather than treating the blood count as the only goal. For other study designs, see our dupilumab evidence questions and nemolizumab itch-trial guide.
Daily dry-skin care serves a different purpose. Dr. Arsy Moisturizer #003, 4 oz provides cosmetic hydration, moisture-barrier support and dry-skin comfort. It was not tested in HILLIER and does not treat eczema, alter eosinophils or replace prescribed treatment.
Adult educational content; research and label checked November 9, 2026. The AI-created sports product image illustrates daily life, not a patient outcome.