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A Study to Learn About Ritlecitinib for the Potential Treatment of Chronic Spontaneous Urticaria in Adults.

A PHASE 2B RANDOMIZED, DOUBLE-BLIND, 12-WEEK PLACEBO-CONTROLLED STUDY WITH A 12-WEEK DOUBLE-BLIND EXTENSION PERIOD TO EVALUATE THE EFFICACY, SAFETY AND TOLERABILITY OF RITLECITINIB (PF-06651600) IN ADULT PARTICIPANTS WITH CHRONIC SPONTANEOUS URTICARIA

Status
Recruiting
Phases
Phase 2
Study type
Interventional
Source
JPRN
Registry ID
JPRN-jRCT2061250065
Enrollment
150
Registered
2025-11-14
Start date
2026-03-11
Completion date
Unknown
Last updated
2026-09-14

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Chronic Spontaneous Urticaria

Interventions

*Ritlecitinib 50 mg Capsule *Ritlecitinib 100 mg Capsule *Placebo Matching Capsule of Ritlecitinib 50 mg *Placebo Matching Capsule of Ritlecitinib 100 mg (Other Names of Ritlecitinib: PF-06651600, Lit

Sponsors

Kawai Norisuke
Lead Sponsor

Eligibility

Sex/Gender
All

Inclusion criteria

Inclusion criteria: Inclusion Criteria: Age: 1. 18 years of age or older (or the minimum legal adult age as defined per local regulations, whichever is greater) at screening. Disease Characteristics: 2. Participants must meet the following Chronic Spontaneous Urticaria (CSU) criteria: a. Chronic spontaneous urticaria diagnosis for >=3 months at the time of screening (with the onset date assessed by the Investigator based on all available records) b. Diagnosis of CSU inadequately controlled by second generation antihistamine (sgAH) at the time of randomization, defined as: (i) The presence of itch and hives for >=6 consecutive weeks prior to screening despite the use of sgAH during this time period. (ii) Participants must have been on a sgAH at locally approved dose or higher for treatment of CSU for at least 7 consecutive days before screening assessment of UAS7 and ISS7 is initiated. (iii) Urticaria Activity Score 7 (UAS7) >=16 (range 0-42) and an Itch Severity Score 7 (ISS7) >=8 (range: 0-21) during the 7 days prior to randomization Day 1 c. Participants must complete at least 5 Urticaria Activity Score (UAS) eDiary entries during the 7 days immediately preceding randomization (Day 1) to confirm eligibility. If this requirement is not met due to documented, limited circumstances such as technical issues or short-term illness, the screening period may be extended only for the number of days necessary to allow completion of 5 UAS entries within any 7-day window. This extension period must not exceed 7 days. d. Anti-Immunoglobulin E-naive (IgE-naive) and Anti-Immunoglobulin E-experienced (Anti-IgE-experienced) participants. Anti-IgE-experienced participants are defined as meeting any of the following criteria confirmed by the Site Investigator: (i) Did not adequately respond to the approved dosage of an anti-IgE therapy (eg, omalizumab 300 mg Q4W or an alternate approved anti-IgE therapy) for at least 3 months, as assessed by the Investigator (ii) Could not tolerate an anti-IgE therapy (iii) Stopped an anti-IgE therapy for any reason, eg, loss of access e. Anti-IgE-experienced participants must have stopped anti-IgE therapy for at least 16 weeks, or 5 half-lives, whichever is longer, prior to randomization Day 1

Exclusion criteria

Exclusion criteria: Exclusion Criteria: Medical Conditions: 1. Medical conditions pertaining to CSU and other diseases/conditions affecting the skin -Urticaria is solely due to inducible urticaria. -Active dermatologic diseases (or conditions) other than chronic urticaria, with urticaria wheals or angioedema symptoms, including but not limited to urticarial vasculitis, erythema multiforme, cutaneous mastocytosis (urticaria pigmentosa) and hereditary or acquired angioedema (eg, due to Complement 1 (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, bullous pemphigoid , dermatitis herpetiformis, senile pruritus, etc.). 2. History of severe allergic or anaphylactoid reaction to any kinase inhibitor or a known allergy/hypersensitivity to any component (including excipients) of the study intervention. 3. General Infection History: -Having a history of systemic infection requiring hospitalization or parenteral therapy (antimicrobial, antiviral, antiparasitic, antiprotozoal, or antifungal), or as otherwise judged clinically significant by the investigator, within 3 months prior to Day 1. -Have active acute or chronic infection requiring treatment with oral antibiotics, antivirals, antiparasitics, antiprotozoals, or antifungals within 4 weeks prior to Day 1. -Evidence or history of untreated, currently treated or inadequately treated active or latent infection with Mycobacterium tuberculosis. 4. Specific Viral Infection History -History (single episode) of disseminated herpes zoster or disseminated herpes simplex, or a recurrent (more than one episode of) localized, dermatomal herpes zoster. -Infected with hepatitis B or hepatitis C viruses: all participants will undergo screening for hepatitis B and C for eligibility. -Have a known immunodeficiency disorder (including positive serology for HIV at screening) or a first-degree relative with a hereditary immunodeficiency (unless known negative carrier status). 5. Other Medical Conditions -Current or recent history of clinically significant severe, progressive, or uncontrolled renal (including but not limited to active renal disease or recent kidney stones), hepatic, hematological, gastrointestinal, metabolic, endocrine (eg, untreated hyperthyroidism or hypothyroidism), pulmonary, cardiovascular, psychiatric, immunologic/rheumatologic or neurologic disease; or have any other severe acute or chronic medical or psychiatric condition or laboratory abnormality that may increase the risk associated with study participation or investigational product administration, or interfere with the interpretation of study results; or in the opinion of the investigator or Pfizer (or designee), the participant is inappropriate for entry into this study, or unwilling/unable to comply with study procedures and lifestyle requirements. -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 acute, fluctuating, or progressive. -Abnormal findings on the screening chest imaging (eg, chest x-ray) including, but not limited to, presence of active TB or other infections, cardiomyopathy, or malignancy. Chest imaging may be performed up to 12 weeks prior to Screening. -Have any malignancies or have a history of malignancies wi

Design outcomes

Primary

MeasureTime frame
*Change from baseline in Urticaria Activity Score 7 (UAS7) at Week 12 *Incidence of Treatment Emergent Adverse Events, Serious Adverse Events, and Adverse Events leading to discontinuation

Secondary

MeasureTime frame
*Change from baseline in UAS7 at all timepoints except Week 12 *Change from baseline in Itch Severity Score 7 (ISS7) at Week 12 *Change from baseline in Hives Severity Score 7 (HSS7) at Week 12 *Achieving complete response defined as UAS7=0 at Week 12 *Achieving UAS7 =10 in UAS7 *Incidence of TEAEs, SAEs, and AEs leading to discontinuation after Week 12 through Week 24

Countries

Bulgaria, Canada, China, Germany, Japan, Poland, South Korea, Spain, Taiwan, United States

Contacts

Public ContactClinical Trials Information Desk

Pfizer R&D Japan G.K.

clinical-trials@pfizer.com+81-3-5309-7000

Outcome results

None listed

Source: JPRN (via WHO ICTRP) · Data processed: Sep 19, 2026