NCT06873945 · Pfizer
A Study of 2 Doses of Ritlecitinib in People 12 Years of Age and Older With Alopecia Areata
(ALLEGRO-100)
What this study is about
The purpose of the study is to learn about the safety and effects of the study medicine (called ritlecitinib) for the treatment of alopecia areata. Alopecia areata is a disease that causes hair loss on the scalp, face, and areas of the body.
View original scientific description
The purpose of the study is to learn about the safety and effects of the study medicine (called ritlecitinib) for the treatment of alopecia areata. Alopecia areata is a disease that causes hair loss on the scalp, face, and areas of the body. Ritlecitinib is approved in many countries at a dose of 50 mg (milligram) taken by mouth once a day for the treatment of patients 12 years and older with severe alopecia areata. This study will look at both the 50 mg dose and a 100 mg dose.
Interventions
DRUG
Ritlecitinib 100 mg
100 mg Capsule
DRUG
Ritlecitinib 50 mg
50 mg Capsule
DRUG
Placebo - 100 mg
Capsule (to match Ritlecitinib 100 mg)
DRUG
Placebo - 50 mg
Capsule (to match Ritlecitinib 50 mg)
Primary outcome measures
Part 1: Percentage of participants with absolute Severity of Alopecia Tool (SALT) score less than or equal to 20
Time frame: Week 24
Difference in the percentage of participants with SALT score less than or equal to 20 between ritlecitinib 100 mg once-daily (QD) versus placebo
Part 2: Percentage of participants with TEAEs, SAEs, and AEs leading to discontinuation
Time frame: Baseline to Follow-up visit (Week 52)
Percentage of participants with events, based on those reported in the study including the safety follow-up period for ritlecitinib 100 mg QD
Part 2: Percentage of participants with clinically significant laboratory abnormalities
Time frame: Baseline to Follow-up visit (Week 52)
Percentage of participants with clinically significant laboratory abnormalities, based on those reported in the study including the safety follow-up period for ritlecitinib 100 mg QD
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- Age: 1. 18 years of age or older at screening. Adolescents (12 to \<18 years of age at screening) are also eligible for this study, but only if permitted by the local IRB/EC and local regulatory health authority (if applicable). Where these approvals have not been granted, only participants 18 years of age and older at screening will be enrolled. Disease Characteristics: 2. Must meet the following alopecia areata criteria at both Screening and Baseline: 1. Have a clinical diagnosis of alopecia areata with no other etiology of hair loss. 2. ≥50% hair loss of the scalp, as measured by SALT, without evidence of terminal hair regrowth within the previous 6 months. 3. Current episode of hair loss ≤10 years.
Exclusion criteria
- Medical Conditions: 1. Diseases or conditions other than alopecia areata which affect hair loss, including other types of alopecia, other scalp disease that may impact the alopecia areata assessment, or active systemic diseases t
Where
- Birmingham, Alabama
- Hot Springs, Arkansas
- Brea, California
- Encinitas, California
- Huntington Beach, California
- Irvine, California
- Santa Ana, California
- Fairfield, Connecticut
- Fort Myers, Florida
- Miami, Florida
- Tampa, Florida
- Chicago, Illinois
And 30 more locations — see the full list below.
Related conditions & keywords
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Aug 13, 2026 · Source of record for eligibility and locations