Testing ritlecitinib for chronic spontaneous urticaria

A Single-center, Single-arm, Open-label Phase IIA Clinical Trial to Investigate Efficacy and Safety of Ritlecitinib (PF-06651600) in Participants With Chronic Spontaneous Urticaria

Phase 2 Interventional Icahn School of Medicine at Mount Sinai · NCT06795373

This study is testing a new medication called ritlecitinib to see if it can help adults with chronic hives and itching that don't get better with regular allergy medicines.

Quick facts

PhasePhase 2
Study typeInterventional
Enrollment20 (estimated)
Ages18 Years to 65 Years
SexAll
SponsorIcahn School of Medicine at Mount Sinai Academic / other
Drugs / interventionsomalizumab, ligelizumab, ritlecitinib
Locations1 site (New York, New York)
Trial IDNCT06795373 on ClinicalTrials.gov

What this trial studies

This clinical trial evaluates the safety and effectiveness of ritlecitinib in treating chronic spontaneous urticaria (CSU), a condition characterized by persistent hives and itching lasting over six weeks. Participants aged 18 to 65 with CSU inadequately controlled by antihistamines will take ritlecitinib for 12 weeks and maintain a daily diary of their symptoms. The study will include physical examinations, blood tests, skin assessments, and optional biopsies over a 20-week period with seven clinic visits. The trial aims to gather data on the drug's impact on CSU symptoms and overall patient well-being.

Who should consider this trial

Good fit: Ideal candidates are adults aged 18 to 65 with a diagnosis of chronic spontaneous urticaria that has not been adequately controlled by antihistamines.

Not a fit: Patients with CSU who have not experienced inadequate control with antihistamines or those outside the age range may not benefit from this study.

Why it matters

Potential benefit: If successful, this treatment could provide significant relief for patients suffering from chronic spontaneous urticaria.

How similar studies have performed: While ritlecitinib is FDA-approved for another condition, its application for chronic spontaneous urticaria is novel and has not been extensively tested in prior studies.

Eligibility criteria

Show full inclusion / exclusion criteria
INCLUSION CRITERIA:

Participants are eligible to be included in the study only if all the following criteria apply:

* Participant has been informed about study procedures and medications and has provided informed consent prior to initiation of any study-specific activities/procedures
* Participant is able to communicate with the investigator, and understands and complies with the requirements of the study
* Age ≥ 18 to ≤ 65 years of age at screening
* Participant has a negative Tuberculin purified protein derivative (PPD) or QuantiFERON TBGold test (QFT) at screening or within the last 12 months.
* Chronic spontaneous urticaria diagnosis ≥ 3 months at the time of screening visit 1
* Diagnosis of CSU inadequately controlled by second-generation H1-antihistamines (sgAH) at enrollment, as defined by the following:

  * The presence of itch and hives for ≥ 6 consecutive weeks at any time prior to screening visit 2 despite current use of an approved dose of H1-antihistamine
  * Urticaria Activity Score over 7 days (UAS7) (range 0-42) ≥ 16 and Hive Severity Score over 7 days (HSS7) (range 0-21) ≥ 8 during the 7 days prior to enrollment
* Participant must have been on or failed a sgAH at approved or increased doses (up to 2 or 4x the approved dose) for treatment of CSU prior to the Baseline visit and must have documented current use on the day of screening visit ○ If participants are currently on a sgAH, they must continue the same dose throughout the trial

EXCLUSION CRITERIA:

Disease Related

* Urticaria is solely due to inducible urticaria
* Active dermatologic diseases (or conditions) other than chronic urticaria, with urticaria wheals or angioedema symptoms such as urticarial vasculitis, erythema multiforme, cutaneous mastocytosis (urticaria pigmentosa) and hereditary or acquired angioedema (eg, due to C1 inhibitor deficiency)
* Any other active skin disease associated with chronic itching that might influence, in the investigator's opinion, the study evaluations and results (eg, atopic dermatitis, dermatitis herpetiformis, senile pruritus, etc.)

Other Medical Conditions

* History of, or a concurrent, clinically significant illness, medical condition or laboratory abnormality that, in the investigator's opinion, could affect the conduct of the study
* Active immunosuppression by previous (5 x half-lives or 12 weeks, whichever is longer) or current systemic cytotoxic therapies
* Uncontrolled current illness, including, but not limited to the following: Ongoing or active infections requiring intravenous antimicrobials; symptomatic congestive heart failure defined as NYHA class III or IV; unstable angina pectoris within 6 months of study enrollment; history of myocardial infarction, stroke or intracranial hemorrhage within 6 months prior to enrollment; moderate to severe hepatic impairment (Child-Pugh class B or C); psychiatric illness or social situations that would limit compliance with study requirements
* Previous or current cancer, except curatively treated basal or squamous cell carcinoma of the skin, and curatively treated malignant melanoma stage 0-1A with a low risk of recurrence/metastasis as per assessment of the investigator, cervical carcinoma in situ, treated basal cell carcinoma, superficial bladder tumors (Ta, Tis and T1)
* Known HIV infection
* Infected with Hepatitis B or Hepatitis C viruses
* Participants with history of either untreated or inadequately treated latent or active TB infections/currently being treated for active TB
* Recent (within 21 days before visit 1) major surgery
* Participants who have history of a single episode of disseminated HZ or disseminated HS or recurrent (\> 1 episode of) localized dermatomal HZ should be excluded
* Any gastrointestinal or metabolic condition that could interfere with the absorption of the oral medication
* History of thrombosis/thromboembolic event, known coagulopathy
* Have hearing loss with progression over the previous 5 years, sudden hearing loss, or middle or inner ear disease such as otitis media, cholesteatoma, Meniere's disease, labyrinthitis, or other auditory condition that is considered current, fluctuating, or progressive.
* Abnormality in hematology, chemistry profiles, or ECG during screening:

  * Platelet count: \<100,000/ mm3
  * Lymphocytes: \<600/ mm3
  * Absolute neutrophil count: \<1200/ mm3
  * Hemoglobin: \<9.0 g/dL
  * ALT or AST: \>3.0xULN
  * eGFR: \<30 mL/min
  * ECG that demonstrates clinically relevant abnormalities that may affect participant safety

Prior/Concomitant Therapy

* Less than 3 months have elapsed since last JAK inhibitors
* Glucocorticosteroids when used systematically within 1 month prior to visit 2
* Prior treatment with other concomitant investigational agents
* Hypersensitivity or allergic reaction to compounds related to JAK inhibitors
* Treatment with medication that might interfere with blood levels or have a major impact on the clinical readout of the study drug, as per discretion of the study investigator
* Participants who have received prohibited drugs that are CYP3A inducers within a 28 day or 5 half-lives (whichever is longer) period prior to the first dose of study intervention
* Participants who have received prohibited drugs that are CYP3A4 or CYP1A2 substrates with narrow therapeutic index where small concentration changes may lead to serious adverse reactions within 1 week or 5 half-lives (whichever is longer) period prior to the first dose of study intervention
* Participant has received a live attenuated vaccine ≤ 30 days prior to study screening
* Treatment with any anti-IgE therapies (eg, omalizumab, ligelizumab) within 1 months prior to screening visit

Other Exclusions

* Pregnant or breast-feeding women
* Unwillingness or inability to use a contraception method during the time of participation in the trial
* Active alcohol and/or drug abuse
* Participant is unable to complete a participant diary or complete questionnaires, or does not meet the required level of compliance (≥ 80%) with the diary

Where this trial is running

New York, New York

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Chronic Spontaneous UrticariaCSURitlecitinib
Last reviewed 2026-06-09 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.