PsoriasisPhase 2NCT06723171
Evaluation of Safety and Efficacy of IRX4204 in Mild to Moderate Plaque Psoriasis
A Phase 2 study testing IRX4204 in people with Psoriasis and Plaque Type Psorisis, run by Io Therapeutics at 1 site in United States.
Trial summary
The goal of this clinical trial is to learn if IRX4204 works to treat plaque psoriasis in adults. It will also learn about the safety of IRX4204. The main questions it aims to answer are: Does IRX4204 treat plaque psoriasis symptoms? Does IRX4204 treat plaque psoriasis symptoms better than someone who is not being… Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Psoriasis, Plaque Type Psorisis, Plaque Psoriasis
- What is being tested?
- IRX4204
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 20 participants
- Where
- 1 siteUnited States
- Study dates
- 1 Mar 2026to Apr 2026
- Phase
- Phase 2
- Are there results?
- None posted in the registry
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
- At least 18 years of age
- Have a diagnosis of plaque psoriasis (with or without psoriatic arthritis) for at least 6 months before the first administration of study treatment
- Meet the following disease severity criteria for moderate to severe plaque psoriasis at Screening and Baseline visits:
- IGA Score of 3 or 4 AND
- Total affected body surface area of >3 to 10% for moderate and 10% to 15% for severe psoriasis
- Excludes participants with scalp only plaques
Show all 16Show fewer
- Be inadequately controlled with or intolerant of at least one prior topical therapy including but not limited to: corticosteroids, retinoids, vitamin D, vitamin D/steroid and retinoid/steroid combinations, tacrolimus, pimecrolimus, anthralin/dithranol, coal tar preparations, tapinarof, roflumilast for the treatment of psoriasis at both Screening and Baseline visits
- In the opinion of the Investigator, be a candidate for phototherapy or systemic treatment for psoriasis
- Completed appropriate washouts for prior treatments for psoriasis
- Be considered, in the opinion of the Investigator, suitable candidates for RXR agonist therapy
- Women participants of childbearing potential (WOCBP) (see Section 8.1.10) or sexually active male participants with partners of childbearing potential agree to practice a highly effective method of contraception (failure rate of < 1% per year when used consistently and correctly; see Section 8.1.10.1) prior to receiving, while receiving, and for at least 6 months after receiving the last administration of study intervention
- WOCBP must have a negative highly sensitive serum beta-human chorionic gonadotropic (b-hCG) pregnancy test at Screening and confirmed at Baseline prior to receiving the first administration of study drug
- WOCBP must agree not to donate eggs (ova, oocytes) or freeze for future and males must agree not to donate sperm for the purpose of reproduction for at least 6 months after receiving the last administration of study intervention.
- Female participants must agree to not breastfeed while enrolled in this study and within 6 months after the last dose of study intervention
- Sign an informed consent form (ICF) indicating that the participant understands the purpose of, and procedures required for, the study and is willing to participate in the study
- Be willing to and able to adhere to the requirements in this protocol
Who cannot join
- Has more than 15% of total body surface area affected by psoriasis plaques
- Has a non-plaque form of psoriasis (e.g., erythrodermic, guttate, or pustular) at Screening or at time of randomization
- Has current drug-induced psoriasis (e.g., a new onset of psoriasis or an exacerbation of psoriasis from beta-blockers, calcium channel blockers, or lithium)
- Has confounding diagnoses including but not limited to palmoplantar pustulosis, eczematous dermatitis, contact/irritant dermatitis, acquired keratoderma
- Has received within 12 weeks of the first dose (Day 1) any prior biologic (or biosimilars of) for the treatment of psoriasis, psoriatic arthritis, or any other indications that could impact the assessment of psoriasis. Prior biologic therapy includes but is not limited to TNF-inhibitors, IL-17 inhibitors, IL-12/23 inhibitors, IL-23 inhibitors
- Has received within 4 weeks of the first dose (Day 1) any systemic immunosuppressives for the treatment of psoriasis or psoriatic arthritis, or any other indications that could impact the assessment of psoriasis, Phototherapy or narrow band laser (e.g., Excimer or XTRAC), lithium, antimalarials, or intramuscular (IM) gold. Systemic immunosuppressive therapy includes but is not limited to methotrexate, azathioprine, cyclosporine, JAK/TYK pathway inhibitors, 6-thioguanine, mercaptopurine, mycophenolate mofetil, tacrolimus, acitretin, or anakinra
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- Has received within 2 weeks of the first dose (Day 1) any topical medications for psoriasis or other conditions that could impact assessment of psoriasis, including but not limited to topical corticosteroids, retinoids, vitamin D analogs, combinations of calcipotriene and topical corticosteroids, tacrolimus, pimecrolimus, anthralin/dithranol, coal tar preparations, PDE4 inhibitors (e.g. crisaborole), or other topicals used for the treatment of psoriasis (tapinarof, roflumilast etc.)
- Has received within 12 weeks or 5 half-lives (whichever is longer) of the first dose (Day 1) other biologic therapy or experimental antibody, any agent that modulates T-cells (e.g., natalizumab, abatacept etc.)
- Has received within 4 weeks or 5 half-lives (whichever is longer) of the first dose (Day 1) any other experimental systemic therapy for any indication
- Is currently enrolled in another study using an investigational agent or procedure
- Has evidence of skin conditions that could interfere with clinical assessments of psoriasis (e.g. eczema, seborrheic dermatitis, or pityriasis rosea)
- Has a current history of severe, uncontrolled or progressive systemic medical conditions including renal, cardiac, vascular, pulmonary, gastrointestinal, endocrine, neurologic, hematologic, rheumatologic, psychiatric, or metabolic disturbances
- Has unstable cardiovascular disease, defined as a recent clinical deterioration in the last 3 months (e.g., unstable angina, atrial fibrillation) or a cardiac hospitalization within the last 3 months
- Currently has a known malignancy or has a history of malignancy within 5 years before screening with the exception of non-melanoma skin cancer curatively treated with no evidence of recurrence for at least 3 months before the first study drug administration or cervical carcinoma in situ of the cervix that has been treated with no evidence of recurrence for at least 3 years before the first study drug administration
- Has a history of lymphoproliferative disease, including lymphoma, leukemia, monoclonal gammopathy, or signs/symptoms suggestive of possible lymphoproliferative disease
- Has a transplanted organ (with the exception of a corneal transplant > 3 months before the first study drug administration)
- Has unstable suicidal ideation or suicidal behavior, or a suicide attempt (including interrupted, aborted attempts and preparatory behaviors for suicide attempt), in the last 6 months
- Has had a major surgery within 8 weeks of Screening or has such surgery planned during the time participant is expected to participate in the study
- Has had a substance abuse problem within the previous 12 months
- Has a history of chronic or recurrent infectious disease including but not limited to chronic renal infection, recurrent urinary tract infection (UTI), chronic respiratory infections (e.g., tuberculosis), skin infections, or fungal infections
- Is currently being treated for a thyroid condition or have abnormalities in TSH, free T4 or T3 at Screening
- Has had a serious infection (e.g., sepsis, pneumonia, pyelonephritis) requiring hospitalization within the 2 months before Screening
- Has had herpes zoster (shingles) within 2 months prior to Screening
- Has an active tuberculosis (TB) infection as confirmed by TB test during screening
- Tests positive for hepatitis B virus (HBV) infection
- Is seropositive for antibodies to hepatitis C virus (HCV). If the antibody test result is positive at screening, the participant will be allowed to be re-screened one time and enrolled after a negative HCV RNA test result
- Is infected with human immunodeficiency virus (HIV)
- Unable to avoid prolonged sun exposure or use of tanning beds or other ultraviolet light sources
- Has received within 2 weeks of the first dose (Day 1) any prescribed anticoagulant, including but not limited to coumarins (such as warfarin), factor Xa inhibitors (i.e., apixaban, rivaroxaban), heparins (e.g., heparin, enoxaparin), and direct thrombin inhibitors
- Has any condition that, in the opinion of the Investigator, would make participation not be in the best interest of the participant or that could prevent, limit, or confound the protocol-specified assessments
- Is an employee of the Investigator or study site, with direct involvement in the proposed study or other studies under the direction of that Investigator or study site, as well as family members of the employees or the Investigator
- Any abnormal laboratory value greater than 2.5 times upper limit of normal (ULN). If one or more of the laboratory parameters is out of range, a single retest of laboratory values is permitted
Trial locations and contacts
1 site in 1 country.
About this study
Official title: A 4-Week, Multicenter, Double-Blind, Placebo-Controlled Study Evaluating the Safety and Efficacy of the RXR Agonist Compound IRX4204 for the Treatment of Mild to Moderate Plaque Psoriasis
The goal of this clinical trial is to learn if IRX4204 works to treat plaque psoriasis in adults. It will also learn about the safety of IRX4204. The main questions it aims to answer are:
- Does IRX4204 treat plaque psoriasis symptoms?
- Does IRX4204 treat plaque psoriasis symptoms better than someone who is not being treated?
- What medical problems do participants have when taking IRX4204?
Read more
Researchers will compare IRX4204 to a placebo (a look-alike substance that contains no drug) to see if the drug works to treat mild to moderate plaque psoriasis.
Participants will:
- Take IRX4204 every day for 28 days
- Visit the clinic once every week for checkups and tests
- Complete specific assessments about plaque psoriasis and changes to plaques
- Conditions
- Psoriasis, Plaque Type Psorisis, Plaque Psoriasis
- Being tested
- IRX4204, Placebo
- Keywords
- RXR, Psoriasis, plaque psoriasis, plaques, mild psoriasis, IRX4204, IO Therapeutics
- Medical subject headings
- Psoriasis, Plaque, Amyloid
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
IRX4204Drug
Also called IRX4204Psoriasis, NRX194204
Active Treatment
PlaceboOther
Placebo
| Study group | Role | What they receive |
|---|---|---|
| Treatment | Active comparator | IRX4204 Receives: Drug: IRX4204 |
| Placebo | Placebo comparator | Placebo Receives: Other: Placebo |
What is being measured
The primary outcome is the main question the study is designed to answer.
To evaluate if participants receiving IRX4204 achieve greater reduction in IGA scores when compared to participants receiving placebo
Percentage of participants achieving an Investigator's Global Assessment (IGA) score of clear (0) or almost clear (1) at Day 28 with at least a 2-grade improvement from Baseline to end of study.
Measured: Baseline (Day 1) to Day 42
Secondary outcomes (4)
To evaluate if participants receiving IRX4204 have greater improvement in participant reported outcomes when compared to participants receiving placebo
Change in Daily Quality of Life Index (DLQI) score will be evaluated. The DLQI is calculated by adding the score of each question, resulting in a minimum of 0 to a maximum of 30. The higher the score, the more quality of life is impaired.
Measured: from Baseline (Day 1) to Day 28
To evaluate if participants receiving IRX4204 experience a greater reduction in affected Body Surface Area when compared to participants receiving placebo
Percent change in affected Body Surface Area (BSA) from Baseline to end of treatment will be evaluated. The body surface area refers to the total amount of skin on the body that is covered by psoriasis lesions and used to assess the severity of the condition. A higher percentage indicates a more severe case of psoriasis.
Measured: from Baseline (Day 1) to Day 28
To evaluate if a greater proportion of participants receiving IRX4204 achieve PASI50, PASI75 and PASI90 when compared to participants receiving placebo
Proportion of participants to achieve PASI50 (50% or greater improvement from Baseline), PASI75, and PASI90 to the end of the study will be evaluated. Achieving PASI 50, PASI 75, and PASI 90 indicates different levels of improvement in psoriasis severity as measured by the Psoriasis Area and Severity Index (PASI) score, with PASI 50 indicating a 50% reduction from baseline, PASI 75 signifying a 75% reduction, and PASI 90 representing a 90% reduction in psoriasis symptoms. Higher PASI numbers signifying increasingly clearer skin.
Measured: from Baseline (Day 1) to End of Study (Day 42)
To evaluate if participants receiving IRX4204 achieve greater improvement from baseline in disease and symptom severity as measured by the Psoriasis Area and Severity Index (PASI).
Change From Baseline to Day 28 in mean Psoriasis Area and Severity Index (PASI) score of participants receiving IRX4204 compared to placebo.
Measured: from Baseline (Day 1) to End of Treatment (Day 28)
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted9 Dec 2024
- Study start1 Mar 2026 (estimated)
- Primary completionMar 2026 (estimated)
- Study completionApr 2026 (estimated)
Why it stopped: Sponsor request for study hold
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for PsoriasisStudies 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
- Parallel groups
- Model description
- Double-blind, placebo controlled
- Masking
- Quadruple blind
- Who is masked
- Participant, Care provider, Investigator, Outcomes assessor
- Enrolment
- 20 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Io Therapeutics
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06723171
- Sponsor's protocol ID
- IRX4204Psoriasis201
- Status last verified
- Apr 2025
- First submitted
- 4 Dec 2024
- Last updated
- 3 Mar 2026
- Results posted
- No
- Data monitoring committee
- No
- 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 3 Mar 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A 4-Week, Multicenter, Double-Blind, Placebo-Controlled Study Evaluating the Safety and Efficacy of the RXR Agonist Compound IRX4204 for the Treatment of Mild to Moderate Plaque Psoriasis
- ClinicalTrials.gov ID
- NCT06723171
- Acronym / sponsor ID
- IRX4204Psoriasis201
- Conditions
- Psoriasis, Plaque Type Psorisis, Plaque Psoriasis
- Keywords
- RXR, Psoriasis, plaque psoriasis, plaques, mild psoriasis, IRX4204, IO Therapeutics
- Phase
- Phase 2
- Study type
- Interventional
- Recruitment status
- SuspendedReason stopped: Sponsor request for study hold
- Enrolment
- 20 participants (estimated)
- Lead sponsor
- Io TherapeuticsIndustry (pharma, biotech, devices)
- Study start
- 1 Mar 2026 (estimated)
- Primary completion
- Mar 2026 (estimated)
- Study completion
- Apr 2026 (estimated)
- First posted
- 9 Dec 2024 (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.
The goal of this clinical trial is to learn if IRX4204 works to treat plaque psoriasis in adults. It will also learn about the safety of IRX4204. The main questions it aims to answer are:
- Does IRX4204 treat plaque psoriasis symptoms?
- Does IRX4204 treat plaque psoriasis symptoms better than someone who is not being treated?
- What medical problems do participants have when taking IRX4204?
Researchers will compare IRX4204 to a placebo (a look-alike substance that contains no drug) to see if the drug works to treat mild to moderate plaque psoriasis.
Participants will:
- Take IRX4204 every day for 28 days
- Visit the clinic once every week for checkups and tests
- Complete specific assessments about plaque psoriasis and changes to plaques
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Quadruple blind (participant, care provider, investigator, outcomes assessor)
- Number of arms
- 2
- Model description
- Double-blind, placebo controlled
| Arm | Type | Receives |
|---|---|---|
| Treatment | Active comparator | Drug: IRX4204IRX4204 |
| Placebo | Placebo comparator | Other: PlaceboPlacebo |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (16 listed)
- At least 18 years of age
- Have a diagnosis of plaque psoriasis (with or without psoriatic arthritis) for at least 6 months before the first administration of study treatment
- Meet the following disease severity criteria for moderate to severe plaque psoriasis at Screening and Baseline visits:
- Be inadequately controlled with or intolerant of at least one prior topical therapy including but not limited to: corticosteroids, retinoids, vitamin D, vitamin D/steroid and retinoid/steroid combinations, tacrolimus, pimecrolimus, anthralin/dithranol, coal tar preparations, tapinarof, roflumilast for the treatment of psoriasis at both Screening and Baseline visits
- In the opinion of the Investigator, be a candidate for phototherapy or systemic treatment for psoriasis
Key exclusion criteria (32 listed)
- Has more than 15% of total body surface area affected by psoriasis plaques
- Has a non-plaque form of psoriasis (e.g., erythrodermic, guttate, or pustular) at Screening or at time of randomization
- Has current drug-induced psoriasis (e.g., a new onset of psoriasis or an exacerbation of psoriasis from beta-blockers, calcium channel blockers, or lithium)
- Has confounding diagnoses including but not limited to palmoplantar pustulosis, eczematous dermatitis, contact/irritant dermatitis, acquired keratoderma
- Has received within 12 weeks of the first dose (Day 1) any prior biologic (or biosimilars of) for the treatment of psoriasis, psoriatic arthritis, or any other indications that could impact the assessment of psoriasis. Prior biologic therapy includes but is not limited to TNF-inhibitors, IL-17 inhibitors, IL-12/23 inhibitors, IL-23 inhibitors
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 |
|---|---|---|
| IRX4204Also: IRX4204Psoriasis, NRX194204Active Treatment | Drug | Treatment |
| PlaceboPlacebo | Other | Placebo |
Primary outcome
To evaluate if participants receiving IRX4204 achieve greater reduction in IGA scores when compared to participants receiving placebo
Time frame: Baseline (Day 1) to Day 42
Percentage of participants achieving an Investigator's Global Assessment (IGA) score of clear (0) or almost clear (1) at Day 28 with at least a 2-grade improvement from Baseline to end of study.
4 secondary outcomes
To evaluate if participants receiving IRX4204 have greater improvement in participant reported outcomes when compared to participants receiving placebo
Time frame: from Baseline (Day 1) to Day 28
To evaluate if participants receiving IRX4204 experience a greater reduction in affected Body Surface Area when compared to participants receiving placebo
Time frame: from Baseline (Day 1) to Day 28
To evaluate if a greater proportion of participants receiving IRX4204 achieve PASI50, PASI75 and PASI90 when compared to participants receiving placebo
Time frame: from Baseline (Day 1) to End of Study (Day 42)
To evaluate if participants receiving IRX4204 achieve greater improvement from baseline in disease and symptom severity as measured by the Psoriasis Area and Severity Index (PASI).
Time frame: from Baseline (Day 1) to End of Treatment (Day 28)
Results and safety
Results are not available in the source record.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 3 Mar 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. This study is not recruiting at the moment.
The record lists no contact. Use the official record to reach the sponsor.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 2 study testing IRX4204 in people with Psoriasis and Plaque Type Psorisis, run by Io Therapeutics at 1 site 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 16 inclusion and 32 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: paused, as of the sponsor's last update on 3 Mar 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site 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. 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 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?
Results are not available in the source record.
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?
To evaluate if participants receiving IRX4204 achieve greater reduction in IGA scores when compared to participants receiving placebo (time frame: Baseline (Day 1) to Day 42). 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 3 Mar 2026.