Hereditary AngioedemaPhase 3STOP-HAENCT06960213
STOP-HAE: A Phase 3 Study of ADX-324 in HAE
A Phase 3 study testing ADX-324 in people with Hereditary Angioedema and HAE, run by ADARx Pharmaceuticals, Inc. at 70 sites in 24 countries.
Trial summary
This study will evaluate the efficacy and safety of ADX-324 in participants with Type 1 or Type 2 hereditary angioedema. The study will also evaluate safety, pharmacokinetics (PK), pharmacodynamics (PD), and health-related quality of life measures. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Hereditary Angioedema, HAE, Hereditary Angioedema - Type 1
- What is being tested?
- ADX-324
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 90 participants
- Where
- 70 sitesin 24 countries
- Study dates
- 28 Aug 2025to 31 Dec 2027
- Phase
- Phase 3
- Are there results?
- Not yet: the study is under way
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 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Age ≥18 years at the time of signing informed consent.
- Have a documented diagnosis of HAE-1/HAE-2 (Type I or II)
- Experience ≥1 Investigator-confirmed HAE attack in the first 4 weeks of Screening or ≥2 Investigator-confirmed HAE attacks in 8 weeks of Screening
- Able to use at least one acute therapy to treat HAE attacks (such as a plasma-derived or recombinant C1-INH concentrate or a BK2-receptor antagonist)
Who cannot join
- Concurrent diagnosis of another form of recurrent angioedema (such as acquired angioedema, HAE with normal C1-INH (previously known as HAE Type III), idiopathic angioedema, or recurrent angioedema associated with urticaria).
- Any clinically significant renal disease
- Any clinically significant hepatic disease
- Have used any of the following for long-term prevention of HAE attacks:
- C1-INH agent (CINRYZE, HAEGARDA, RUCONEST) within 2 weeks prior to Screening.
- Berotralstat (ORLADEYO) within 3 weeks prior to Screening.
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- Lanadelumab (TAKHZYRO) within 8 weeks prior to the Screening.
- Androgen use within 12 weeks prior to Screening.
- Received prior treatment with any RNA/DNA-based therapy for HAE or intolerant to any prior RNA/DNA-based therapy for any condition, excluding vaccines.
Trial locations and contacts
70 sites in 24 countries. Contact the study team or a site near you to ask about taking part.
70 sites in 24 countries
United States19 sites, 17 recruiting
- Recruiting
ADARx Clinical Site
Centennial, Colorado, 80112
- Recruiting
ADARx Clinical Site
Chevy Chase, Maryland, 20815
- Recruiting
ADARx Clinical Site
Cincinnati, Ohio, 45236
- Not yet recruiting
ADARx Clinical Site
Cleveland, Ohio, 44195
- Withdrawn
ADARx Clinical Site
Columbus, Ohio, 43235
- Recruiting
ADARx Clinical Site
Detroit, Michigan, 48202
- Recruiting
ADARx Clinical Site
Hershey, Pennsylvania, 17033
- Recruiting
ADARx Clinical Site
Las Vegas, Nevada, 89128
- Recruiting
ADARx Clinical Site
Litchfield Park, Arizona, 85340
- Recruiting
ADARx Clinical Site
Little Rock, Arkansas, 72205
- Recruiting
ADARx Clinical Site
New York, New York, 10029
- Recruiting
ADARx Clinical Site
Orlando, Florida, 32807
- Recruiting
ADARx Clinical Site
San Diego, California, 92122
- Not yet recruiting
ADARx Clinical Site
Santa Monica, California, 90404
- Recruiting
ADARx Clinical Site
Scottsdale, Arizona, 85251
- Recruiting
ADARx Clinical Site
St Louis, Missouri, 63141
- Recruiting
ADARx Clinical Site
Toledo, Ohio, 43617
- Recruiting
ADARx Clinical Site
Walnut Creek, California, 94598
- Withdrawn
ADARx Clinical Site
Wheaton, Maryland, 20902
France5 sites, 5 recruiting
- Recruiting
ADARx Clinical Site
Grenoble, 38043
- Recruiting
ADARx Clinical Site
Montpellier, 34295
- Recruiting
ADARx Clinical Site
Nice, Alpes-Maritimes, 06300
- Recruiting
ADARx Clinical Site
Paris, 75012
- Recruiting
ADARx Clinical Site
Tours, Indre-et-Loire, 37000
United Kingdom5 sites, 5 recruiting
- Recruiting
ADARx Clinical Site
Cambridge, CB2 0QQ
- Recruiting
ADARx Clinical Site
Cardiff, CF14 4YS
- Not yet recruiting
ADARx Clinical Site
Guildford, Surrey, GU2 7XX
- Recruiting
ADARx Clinical Site
London, E1 1BB
- Recruiting
ADARx Clinical Site
Southampton, SO16 6YD
Argentina4 sites, 4 recruiting
- Recruiting
ADARx Clinical Site
Buenos Aires, Buenos Aires F.D., C1035AAT
- Recruiting
ADARx Clinical Site
Capital Federal, Buenos Aires, C1425BEN
- Recruiting
ADARx Clinical Site
Pilar, 1629
- Recruiting
ADARx Clinical Site
Rosario, 2000
Canada4 sites, 2 recruiting
- Withdrawn
ADARx Clinical Site
Edmonton, Alberta, T6G 2R3
- Not yet recruiting
ADARx Clinical Site
Edmonton, Alberta, T6G 2R3
- Recruiting
ADARx Clinical Site
Montreal, Quebec, H2W 1R7
- Withdrawn
ADARx Clinical Site
Ottawa, Ontario, K1H 1E4
Turkey (Türkiye)4 sites, 4 recruiting
- Not yet recruiting
ADARx Clinical Site
Ankara, 06100
- Not yet recruiting
ADARx Clinical Site
Bornova, 35100
- Not yet recruiting
ADARx Clinical Site
Istanbul, 34093
- Not yet recruiting
ADARx Clinical Site
Kayseri, 38039
China3 sites, 3 recruiting
- Recruiting
ADARx Clinical Site
Beijing, 100730
- Not yet recruiting
ADARx Clinical Site
Harbin, 150001
- Not yet recruiting
ADARx Clinical Site
Zhengzhou, 450003
Israel3 sites, 3 recruiting
- Recruiting
ADARx Clinical Site
Ashkelon, 7830604
- Recruiting
ADARx Clinical Site
Ramat Gan, Tel Aviv, 5262100
- Recruiting
ADARx Clinical Site
Tel Aviv, 64239
Poland3 sites, 3 recruiting
- Recruiting
ADARx Clinical Site
Krakow
- Recruiting
ADARx Clinical Site
Lodz, 92-213
- Recruiting
ADARx Clinical Site
Wroclaw, 50-556
Australia2 sites, 2 recruiting
- Recruiting
ADARx Clinical Site
Adelaide, South Australia, 5000
- Not yet recruiting
ADARx Clinical Site
Campbelltown, New South Wales, 2560
Brazil2 sites, 2 recruiting
- Not yet recruiting
ADARx Clinical Site
Campinas, 13073-002
- Not yet recruiting
ADARx Clinical Site
São Paulo, 01246-903
Croatia2 sites, 2 recruiting
- Recruiting
ADARx Clinical Site
Split, 21000
- Recruiting
ADARx Clinical Site
Zagreb, 10000
Czechia2 sites, 2 recruiting
- Recruiting
ADARx Clinical Site
Hradec Králové, 500 05
- Recruiting
ADARx Clinical Site
Prague, 15000
Spain2 sites, 2 recruiting
- Recruiting
ADARx Clinical Site
Barcelona, 08907
- Recruiting
ADARx Clinical Site
Madrid, 28007
Belgium1 site, 1 recruiting
- Recruiting
ADARx Clinical Site
Edegem, Antwerpen, 2650
Germany1 site, 1 recruiting
- Recruiting
ADARx Clinical Site
Tübingen, Baden-Wurttemberg, 72076
South Africa1 site, 1 recruiting
- Not yet recruiting
ADARx Clinical Site
Mowbray, Capetown, 7700
About this study
Official title: STOP-HAE: A Phase 3, Randomized, Double-Blind, Placebo-Controlled Study of siRNA Targeting of Prekallikrein With ADX-324 in Participants With Hereditary Angioedema
This study will evaluate the efficacy and safety of ADX-324 in participants with Type 1 or Type 2 hereditary angioedema. The study will also evaluate safety, pharmacokinetics (PK), pharmacodynamics (PD), and health-related quality of life measures.
- Conditions
- Hereditary Angioedema, HAE, Hereditary Angioedema - Type 1, Hereditary Angioedema - Type 2
- Being tested
- ADX-324, Placebo
- Keywords
- HAE, Hereditary angioedema, onvuzosiran
- Medical subject headings
- Angioedemas, Hereditary
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
ADX-324Drug
Also called siRNA
siRNA duplex oligonucleotide
PlaceboDrug
Also called Saline
saline
| Study group | Role | What they receive |
|---|---|---|
| ADX-324 Dose Level 1 | Experimental | Not described Receives: Drug: ADX-324 |
| ADX-324 Dose Level 2 | Experimental | Not described Receives: Drug: ADX-324 |
| Placebo | Placebo comparator | Not described Receives: Drug: Placebo |
What is being measured
The primary outcome is the main question the study is designed to answer.
Efficacy of ADX-324 in preventing HAE attacks
The time-normalized number of Investigator-confirmed HAE attacks per month for ADX-324 Dose Level 1 vs placebo
Measured: Day 22 to Week 25
Secondary outcomes (5)
Efficacy of ADX-324 in preventing HAE attacks
The time-normalized number of Investigator-confirmed HAE attacks per month for ADX-324 Dose Level 2 vs placebo
Measured: Day 22 to Week 25
Evaluate the effects of ADX-324 on the quality and pattern of HAE attacks
The time-normalized number of Investigator-confirmed HAE attacks requiring acute HAE therapy per month for ADX-324 vs placebo.
Measured: Day 22 to Week 25
Evaluate the effects of ADX-324 on the quality and pattern of HAE attacks
The time-normalized number of moderate or severe Investigator confirmed HAE attacks per month for ADX 324 vs placebo.
Measured: Day 22 to Week 25
Evaluate the effects of ADX-324 on the quality and pattern of HAE attacks
The proportion of participants who have not experienced an Investigator-confirmed HAE attack (HAE attack-free) for ADX 324 vs placebo.
Measured: Day 22 to Week 25
Evaluate the effects of ADX-324 on the quality and pattern of HAE attacks
The proportion of participants with a clinical response defined as a ≥50%, ≥70%, or ≥90% reduction from baseline in Investigator-confirmed HAE attack rate for ADX 324 vs placebo.
Measured: Day 22 to Week 25
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted7 May 2025
- Study start28 Aug 2025
- Primary completion30 Nov 2027 (estimated)
- Study completion31 Dec 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Hereditary AngioedemaStudies 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 3
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Model description
- Randomized, double-blind, placebo-controlled study
- Masking
- Quadruple blind
- Who is masked
- Participant, Care provider, Investigator, Outcomes assessor
- Enrolment
- 90 participants (estimated)
Sponsor and investigators
- Lead sponsor
- ADARx Pharmaceuticals, Inc.
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
- Investigators
- Lauge Farnaes, MD, Study director, ADARx Pharmaceuticals, Inc.
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06960213
- Sponsor's protocol ID
- ADX-324-301
- Acronym
- STOP-HAE
- Status last verified
- Sep 2026
- First submitted
- 7 Apr 2025
- Last updated
- 10 Sep 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- Undecided
Study at a glance
From the registry record, last updated by the sponsor on 10 Sep 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- STOP-HAE: A Phase 3, Randomized, Double-Blind, Placebo-Controlled Study of siRNA Targeting of Prekallikrein With ADX-324 in Participants With Hereditary Angioedema
- ClinicalTrials.gov ID
- NCT06960213
- Acronym / sponsor ID
- STOP-HAE / ADX-324-301
- Conditions
- Hereditary Angioedema, HAE, Hereditary Angioedema - Type 1, Hereditary Angioedema - Type 2
- Keywords
- HAE, Hereditary angioedema, onvuzosiran
- Phase
- Phase 3
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 90 participants (estimated)
- Lead sponsor
- ADARx Pharmaceuticals, Inc.Industry (pharma, biotech, devices)
- Study start
- 28 Aug 2025 (actual)
- Primary completion
- 30 Nov 2027 (estimated)
- Study completion
- 31 Dec 2027 (estimated)
- First posted
- 7 May 2025 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This study will evaluate the efficacy and safety of ADX-324 in participants with Type 1 or Type 2 hereditary angioedema. The study will also evaluate safety, pharmacokinetics (PK), pharmacodynamics (PD), and health-related quality of life measures.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Quadruple blind (participant, care provider, investigator, outcomes assessor)
- Number of arms
- 3
- Model description
- Randomized, double-blind, placebo-controlled study
| Arm | Type | Receives |
|---|---|---|
| ADX-324 Dose Level 1 | Experimental | Drug: ADX-324 |
| ADX-324 Dose Level 2 | Experimental | Drug: ADX-324 |
| Placebo | Placebo comparator | Drug: Placebo |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (4 listed)
- Age ≥18 years at the time of signing informed consent.
- Have a documented diagnosis of HAE-1/HAE-2 (Type I or II)
- Experience ≥1 Investigator-confirmed HAE attack in the first 4 weeks of Screening or ≥2 Investigator-confirmed HAE attacks in 8 weeks of Screening
- Able to use at least one acute therapy to treat HAE attacks (such as a plasma-derived or recombinant C1-INH concentrate or a BK2-receptor antagonist)
Key exclusion criteria (9 listed)
- Concurrent diagnosis of another form of recurrent angioedema (such as acquired angioedema, HAE with normal C1-INH (previously known as HAE Type III), idiopathic angioedema, or recurrent angioedema associated with urticaria).
- Any clinically significant renal disease
- Any clinically significant hepatic disease
- Have used any of the following for long-term prevention of HAE attacks:
- Received prior treatment with any RNA/DNA-based therapy for HAE or intolerant to any prior RNA/DNA-based therapy for any condition, excluding vaccines.
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 |
|---|---|---|
| ADX-324Also: siRNAsiRNA duplex oligonucleotide | Drug | ADX-324 Dose Level 1, ADX-324 Dose Level 2 |
| PlaceboAlso: Salinesaline | Drug | Placebo |
Primary outcome
Efficacy of ADX-324 in preventing HAE attacks
Time frame: Day 22 to Week 25
The time-normalized number of Investigator-confirmed HAE attacks per month for ADX-324 Dose Level 1 vs placebo
5 secondary outcomes
Efficacy of ADX-324 in preventing HAE attacks
Time frame: Day 22 to Week 25
Evaluate the effects of ADX-324 on the quality and pattern of HAE attacks
Time frame: Day 22 to Week 25
Evaluate the effects of ADX-324 on the quality and pattern of HAE attacks
Time frame: Day 22 to Week 25
Evaluate the effects of ADX-324 on the quality and pattern of HAE attacks
Time frame: Day 22 to Week 25
Evaluate the effects of ADX-324 on the quality and pattern of HAE attacks
Time frame: Day 22 to Week 25
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 10 Sep 2026.
- Individual participant dataSharing planned: Undecided
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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.
Lauge Farnaes, MD study director
ADARx Pharmaceuticals, Inc.
70 sites in 24 countries: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 3 study testing ADX-324 in people with Hereditary Angioedema and HAE, run by ADARx Pharmaceuticals, Inc. at 70 sites in 24 countries.
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 4 inclusion and 9 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: looking for participants now, as of the sponsor's last update on 10 Sep 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 70 sites in United States, France, United Kingdom, Argentina, Canada and 19 more countries. 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. Some participants in this study may receive a placebo. 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 3 studies compare the treatment with the current standard treatment or a placebo in a large group, to confirm how well it works and watch for side effects.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Lupe Gallegos (877-232-7974, info@adarx.com), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Efficacy of ADX-324 in preventing HAE attacks (time frame: Day 22 to Week 25). 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 10 Sep 2026.