A Study of 2 Doses of Ritlecitinib in People 12 Years of Age and Older With Alopecia Areata

Inclusion Criteria:

Age:

1. 18 years of age or older at screening. Adolescents (12 to <18 years of age atscreening) are also eligible for this study, but only if permitted by the localIRB/EC and local regulatory health authority (if applicable). Where these approvalshave not been granted, only participants 18 years of age and older at screening willbe enrolled. Disease Characteristics:

2. Must meet the following alopecia areata criteria at both Screening and Baseline:

3. Have a clinical diagnosis of alopecia areata with no other etiology of hairloss.

4. ≥50% hair loss of the scalp, as measured by SALT, without evidence of terminalhair regrowth within the previous 6 months.

5. Current episode of hair loss ≤10 years.

Exclusion Criteria:

Medical Conditions:

1. Diseases or conditions other than alopecia areata which affect hair loss, includingother types of alopecia, other scalp disease that may impact the alopecia areataassessment, or active systemic diseases that may cause hair loss.

2. History of severe allergic or anaphylactoid reaction to any kinase inhibitor or aknown allergy/hypersensitivity to any component (including excipients) of the studyintervention.

3. Any psychiatric condition including recent or active suicidal ideation or behaviorthat meets protocol-defined criteria.

4. General Infection History:

• Have a history of systemic infection requiring hospitalization or parenteraltherapy (antimicrobial, antiviral, antiparasitic, antiprotozoal, orantifungal), 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 oralantibiotics, antivirals, antiparasitics, antiprotozoals, or antifungals within 4 weeks prior to Day 1. NOTE: participants may be rescreened after theinfection resolves.

• Evidence or history of untreated, currently treated or inadequately treatedactive or latent infection with Mycobacterium tuberculosis.

5. Specific Viral Infection History:

• History (single episode) of disseminated herpes zoster or disseminated herpessimplex, or a recurrent (more than one episode of) localized, dermatomal herpeszoster.

• Infected with hepatitis B or hepatitis C viruses: all participants will undergoscreening for hepatitis B and C for eligibility.

6. Other Medical Conditions:

• Have hearing loss with progression over the previous 5 years, sudden hearingloss, or middle or inner ear disease such as otitis media, cholesteatoma,Meniere's disease, labyrinthitis, or other auditory condition that isconsidered 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 toScreening.

• Have any malignancies or have a history of malignancies with the exception ofadequately treated or excised nonmetastatic basal cell or squamous cell cancerof the skin or cervical carcinoma in situ.

• Have a history of any lymphoproliferative disorder such as EBV-relatedlymphoproliferative disorder, history of lymphoma, history of leukemia, orsigns and symptoms suggestive of current lymphatic or lymphoid disease.

• Significant trauma or major surgery within 1 month of the first dose of studydrug or considered in imminent need for surgery.

7. Adolescent participants 12 to <18 years of age without one of the following:

• Documented evidence from a health professional of having received varicellavaccination (2 doses); or

• Evidence of prior exposure to varicella zoster virus (VZV) based on serologicaltesting (ie, a positive VZV IgG Ab result) at Screening.

8. Any medical or laboratory abnormality that may increase the risk of studyparticipation or, in the investigator's judgment, make the participant inappropriatefor the study. Prior/Concomitant Therapy:

9. Current or prior use of any prohibited medication(s), vaccine(s), or treatment(s)within the protocol-defined timelines. Prior/Concurrent Clinical Study Experience:

10. Previous administration with an investigational drug or vaccine within 8 weeks (orlonger as determined by the local requirement) or 5 half-lives (whichever is longer)before the first dose of study intervention in this study. Participation in studiesof other investigational products (drug or vaccine) at any time during theirparticipation in this study. Diagnostic Assessments:

11. Any exclusionary abnormalities in laboratory values at Screening, as assessed by thestudy-specific laboratory and, if deemed necessary, confirmed by a single repeat.

12. Screening standard 12-lead ECG that demonstrates clinically relevant abnormalities. Other Exclusion Criteria:

13. Investigator site staff directly involved in the conduct of the study and theirfamily members, site staff otherwise supervised by the investigator, and sponsor andsponsor delegate employees directly involved in the conduct of the study and theirfamily members.