UrticariaPhase 2NCT05496465
Safety and Efficacy of Intranasal Epinephrine After Administration of ARS -1 in Subjects With Frequent Urticaria Flares
A Phase 2 study testing ARS-1 in people with Urticaria, run by ARS Pharmaceuticals, Inc. at 2 sites in United States.
Trial summary
Determine the effect of ARS-1 on a patient reported pruritus/hive score Read more about this study
- Who is it for?
- Ages 18 to 65 years
- Conditions the study is for
- Urticaria
- What is being tested?
- ARS-1
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 21 participants
- Where
- 2 sitesUnited States
- Study dates
- 28 Jul 2022to 29 Feb 2024
- Phase
- Phase 2
- Are there results?
- Yes, posted in the registrySummary in the doctors' view
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 65 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- 1. Male or female subject between the ages of 18 and 65 years.
- 2. Clinically diagnosed urticaria with acute symptom flares at least two (2) times a week while on a chronic treatment.
- 3. Body weight more than 30 kg and body mass index between 18 and 34 kg/m².
- 4. Has no medical history of hypertension and cardiovascular disease in the last 10 years.
- 5. At screening, has stable vital signs.
- 6. If female, is not pregnant or breastfeeding.
- 7. If male (with or without vasectomy), agree to the use of highly effective contraceptive methods at screening until 7 days after the last day of study drug.
- 8. Is able to communicate clearly with the Investigator and staff. 9. Provide written informed consent prior to participating in the study.
Who cannot join
- 1. History of clinically significant gastrointestinal, renal, hepatic, neurologic, hematologic, endocrine, oncologic, pulmonary, immunologic, psychiatric, or cardiovascular disease.
- 2. Patients receiving beta blocker due to potential interaction with the study drug.
- 3. Prior nasal fractures, severe nasal injuries or history of nasal disorders.
- 4. Clinically significant medical condition or physical exam finding.
- 5. Abnormal cardiovascular exam at screening including any prior history of myocardial infarction or clinically significant abnormal ECG.
- 6. Mucosal inflammatory disorders.
Show all 10Show fewer
- 7. Significant traumatic injury or major surgery within 30 days prior to study screening.
- 8. Has donated blood or had an acute loss of blood (>50 mL) during the 30 days before study drug administration.
- 9. Known hypersensitivity to any compound in the test product.
- 10. Participated in a clinical trial within 30 days prior to the first dose of study drug.
Trial locations and contacts
2 sites in 1 country.
United States2 sites
Massachusetts General Hospital
Boston, Massachusetts, 02114
Bernstein Clinical Research Center, LLC
Cincinnati, Ohio, 45236
About this study
Official title: A Single-Dose, Randomized, Placebo-Controlled, Cross-Over Study of the Safety and Efficacy of Intranasal Epinephrine After Administration of ARS -1 in Subjects With Frequent Urticaria Flares
Determine the effect of ARS-1 on a patient reported pruritus/hive score
- Conditions
- Urticaria
- Being tested
- ARS-1
- Medical subject headings
- Urticaria
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
ARS-1Drug
A single treatment of ARS-1 1mg, 2 mg or placebo
| Study group | Role | What they receive |
|---|---|---|
| Sequence 1 | Experimental | 1 mg ARS-1 IN: placebo: 2 mg ARS-1 IN Receives: Drug: ARS-1 |
| Sequence 2 | Experimental | 2 mg ARS-1 IN: placebo: 1 mg ARS-1 Receives: Drug: ARS-1 |
What is being measured
The primary outcome is the main question the study is designed to answer.
Effect of ARS-1 Versus Placebo Based on a Patient Reported Pruritus/Hive Score
Assess time to effect and duration of effect on acute flares associated with urticaria based on a patient reported pruritus/hive score, from 0 (none) to 3 (severe) for itch and hive using Uniform Assessment System (UAS) as below:
Severity Score Amount of Itch Itch Severity 0 None None
- Mild Easily tolerated
- Moderate Bothersome but tolerable
- Intense Difficult to tolerate
Hive Severity Score Number of Hives 0 None
- 1-6
- 7-12
- >12
Measured: UAS score at 120 (± 10 min) minutes after dosing.
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted11 Aug 2022
- Study start28 Jul 2022
- Primary completion29 Feb 2024
- Study completion29 Feb 2024
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Posted resultsParticipant flow, outcome measures and adverse events reported by the sponsor.
- Other trials for UrticariaStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 2
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Crossover
- Model description
- Each subject received all three treatments in a randomized sequence.
- Masking
- None (open label)
- Enrolment
- 21 participants (actual)
Sponsor and investigators
- Lead sponsor
- ARS Pharmaceuticals, Inc.
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
- Investigators
- Sarina Tanimoto, MD, PhD, Study director, ARS Pharmaceuticals, Inc.
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT05496465
- Sponsor's protocol ID
- RELIEF-CSU1
- Status last verified
- Mar 2026
- First submitted
- 27 Apr 2022
- Last updated
- 7 Apr 2026
- Results posted
- Yes, on ClinicalTrials.gov
- Data monitoring committee
- No
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
Study at a glance
From the registry record, last updated by the sponsor on 7 Apr 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Single-Dose, Randomized, Placebo-Controlled, Cross-Over Study of the Safety and Efficacy of Intranasal Epinephrine After Administration of ARS -1 in Subjects With Frequent Urticaria Flares
- ClinicalTrials.gov ID
- NCT05496465
- Acronym / sponsor ID
- RELIEF-CSU1
- Conditions
- Urticaria
- Phase
- Phase 2
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 21 participants (actual)
- Lead sponsor
- ARS Pharmaceuticals, Inc.Industry (pharma, biotech, devices)
- Study start
- 28 Jul 2022 (actual)
- Primary completion
- 29 Feb 2024 (actual)
- Study completion
- 29 Feb 2024 (actual)
- First posted
- 11 Aug 2022 (actual)
- Results
- Posted 7 Apr 2026
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Determine the effect of ARS-1 on a patient reported pruritus/hive score
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- None (open label)
- Number of arms
- 2
- Model description
- Each subject received all three treatments in a randomized sequence.
| Arm | Type | Receives |
|---|---|---|
| Sequence 1 | Experimental | Drug: ARS-11 mg ARS-1 IN: placebo: 2 mg ARS-1 IN |
| Sequence 2 | Experimental | Drug: ARS-12 mg ARS-1 IN: placebo: 1 mg ARS-1 |
Who may qualify
- Ages
- 18 to 65 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (8 listed)
- 1. Male or female subject between the ages of 18 and 65 years.
- 2. Clinically diagnosed urticaria with acute symptom flares at least two (2) times a week while on a chronic treatment.
- 3. Body weight more than 30 kg and body mass index between 18 and 34 kg/m².
- 4. Has no medical history of hypertension and cardiovascular disease in the last 10 years.
- 5. At screening, has stable vital signs.
Key exclusion criteria (10 listed)
- 1. History of clinically significant gastrointestinal, renal, hepatic, neurologic, hematologic, endocrine, oncologic, pulmonary, immunologic, psychiatric, or cardiovascular disease.
- 2. Patients receiving beta blocker due to potential interaction with the study drug.
- 3. Prior nasal fractures, severe nasal injuries or history of nasal disorders.
- 4. Clinically significant medical condition or physical exam finding.
- 5. Abnormal cardiovascular exam at screening including any prior history of myocardial infarction or clinically significant abnormal ECG.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| ARS-1A single treatment of ARS-1 1mg, 2 mg or placebo | Drug | Sequence 1, Sequence 2 |
Primary outcome
Effect of ARS-1 Versus Placebo Based on a Patient Reported Pruritus/Hive Score
Time frame: UAS score at 120 (± 10 min) minutes after dosing.
Assess time to effect and duration of effect on acute flares associated with urticaria based on a patient reported pruritus/hive score, from 0 (none) to 3 (severe) for itch and hive using Uniform Assessment System (UAS) as below: Severity Score Amount of Itch Itch Severity 0 None None 1. Mild Easily tolerated 2. Moderate Bothersome but tolerable 3. Intense Difficult to tolerate Hive Severity Score Number of Hives 0 None 1. 1-6 2. 7-12 3. >12
Results and safety
Loading the posted results from ClinicalTrials.gov…
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 7 Apr 2026.
- Posted resultsParticipant flow, baseline, all outcome measures and adverse events.
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Long-term Efficacy and Safety Extension (LTE) Study of Barzolvolimab in Participants With Chronic Spontaneous Urticaria
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Sarina Tanimoto, MD, PhD study director
ARS Pharmaceuticals, Inc.
2 sites in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 2 study testing ARS-1 in people with Urticaria, run by ARS Pharmaceuticals, Inc. at 2 sites in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 8 inclusion and 10 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 7 Apr 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 2 sites in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 2 studies give the treatment to a larger group to see whether it has the intended effect and to keep checking safety.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
Yes. Results are posted in the registry (first posted 7 Apr 2026). A summary is in the For doctors view, and the full results are on ClinicalTrials.gov.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Effect of ARS-1 Versus Placebo Based on a Patient Reported Pruritus/Hive Score (time frame: UAS score at 120 (± 10 min) minutes after dosing.). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 7 Apr 2026.