A Phase 1 interventional study of ARQ-234 and Placebo in Atopic Dermatitis (AD) and Eczema, sponsored by Arcutis Biotherapeutics, Inc.. Recruiting at 7 sites in United States. Open to participants aged 18 Years to 65 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-10-23.
Sponsored by Arcutis Biotherapeutics, Inc. · Phase 1, Interventional, and Treatment
This is a first-in-human, Phase 1, double-blind, randomized, placebo-controlled, dose-escalation study evaluating ARQ-234. The study is designed to assess the safety, tolerability, pharmacokinetics (PK), and pharmacodynamics (PD) of ARQ-234 in two populations: healthy volunteers and participants with moderate to severe atopic dermatitis (AD). Healthy volunteers will participate in Single Ascending Dose (SAD) Cohorts 1-5. Participants with moderate to severe AD will be enrolled in SAD Cohorts 6-7, Multiple Ascending Dose (MAD) Cohorts, and a Proof-of-Concept (POC) expansion cohort.
The study consists of 3 parts with staggered initiation:
1,591 studies on the registry are indexed under Dermatitis, Atopic; 286 are open to participants now.
This study's planned enrollment of 125 is above the median of 82 across 1,246 interventional studies indexed under Dermatitis, Atopic.
Browse Dermatitis, Atopic studies →Arcutis Biotherapeutics, Inc. is the lead sponsor of 26 studies on the registry; 2 are open to participants now.
Of its 24 completed or terminated interventional studies of FDA-regulated products, 20 (83%) have results posted.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Inclusion Criteria for atopic dermatitis (AD) Participants (Parts A Cohorts 6-7, Part B, Part C):
Exclusion Criteria (All Participants):
Exclusion Criteria for atopic dermatitis (AD) Participants (Parts A Cohorts 6-7, Part B, Part C):
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
A recording of the heart’s electrical activity, taken with stickers on the chest, arms and legs. It takes a few minutes and does not hurt.
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.
After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
Read whether the line is about a condition or about medicines, and which medicines and doses it means.
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
The other ingredients in a medicine besides the active drug, such as fillers, colours or preservatives.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ECG (electrocardiogram)
A recording of the heart’s electrical activity, taken with stickers on the chest, arms and legs. It takes a few minutes and does not hurt.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Childbearing potential
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hypersensitivity
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis B tests
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis C tests
Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.
After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HIV
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Immunosuppression
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
Read whether the line is about a condition or about medicines, and which medicines and doses it means.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Cancer (malignancy)
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Investigational drug or device
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Excipients
The other ingredients in a medicine besides the active drug, such as fillers, colours or preservatives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Biological: ARQ-234
Drug: Placebo
ARQ-234 subcutaneous injectable solution
Placebo subcutaneous injectable solution
Number and percentage of participants who experience an adverse event (AE) or serious adverse event (SAE)
Time frame: From screening to the last follow up visit for each study part (Part A: 16 weeks, Part B: 30 weeks, Part C: 30 weeks)
Percent change from Baseline in the Eczema Area and Severity Index (EASI) score, a validated measure of disease severity in atopic dermatitis.
Time frame: From Baseline to Week 16
Serum concentrations of study drug to characterize the pharmacokinetic (PK) profile
Time frame: From Baseline to Week 16
Percentage of participants achieving at least a 50% improvement from baseline in EASI total score (EASI-50)
Time frame: From Baseline to Week 16
Percentage of participants achieving at least a 75% improvement from baseline in EASI total score (EASI-75)
Time frame: From Baseline to Week 16
Absolute change and percent change from baseline in the percentage of body surface area affected by atopic dermatitis
Time frame: From Baseline to Week 16
Absolute change and percent change from baseline in itch severity as measured by the Itch Numeric Rating Scale
Time frame: From Baseline to Week 16
Absolute change and percent change from baseline in SCORing Atopic Dermatitis (SCORAD) score
Time frame: From Baseline to Week 16
Percentage of participants achieving at least a 50% improvement from baseline in SCORAD total score
Time frame: From Baseline to Week 16
Percentage of participants achieving at least a 75% improvement from baseline in SCORAD score
Time frame: From Baseline to Week 16
Absolute change and percent change from baseline in Patient-Oriented Eczema Measure (POEM) score
Time frame: From Baseline to Week 16
Percentage of participants achieving a Validated Investigator's Global Assessment (vIGA-AD) score of 0 (Clear) or 1 (Almost Clear) with at least a 2-grade improvement from baseline
Time frame: From Baseline to Week 16
Percentage of participants with a vIGA-AD score of 0 (Clear)
Time frame: From Baseline to Week 16
Plan to share: Undecided
No publications or documents are linked to this record.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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