A Study to Evaluate Efficacy and Safety of Povorcitinib in Participants With Nonsegmental Vitiligo (STOP-V1)

Inclusion Criteria:

• Aged ≥ 18 years.

• Clinical diagnosis of nonsegmental vitiligo and meet the following:

• T-BSA ≥ 5%

• T-VASI score ≥ 4

• F-BSA ≥ 0.5%

• F-VASI score ≥ 0.5

• Agreement to discontinue all agents and procedures used to treat vitiligo fromscreening through the final safety follow-up visit.

• Willingness to avoid pregnancy or fathering children.

Exclusion Criteria:

• Other forms of vitiligo or skin depigmentation disorders.

• Clinically significant abnormal TSH or free T4 at screening.

• Use of laser or phototherapy within 8 weeks and dihydroxyacetone within 4 weeksprior to Day 1.

• Current or past use of the depigmenting agent monobenzyl ether of hydroquinoneincluding Benoquin®.

• History of melanocyte-keratinocyte transplantation procedure or other surgicaltreatment for vitiligo.

• Spontaneous and significant repigmentation within 6 months prior to screening.

• Women who are pregnant, considering pregnancy, or breast feeding.

• Medical history including thrombocytopenia, coagulopathy or platelet dysfunction;venous and arterial thrombosis, deep vein thrombosis, pulmonary embolism, stroke,moderate to severe heart failure, cerebrovascular accident, myocardial infarction,or other significant cardiovascular diseases; Q-wave interval abnormalities;disseminated herpes zoster or recurrent dermatomal herpes zoster; disseminatedherpes simplex; chronic/recurrent infections; malignancies.

• Evidence of infection with TB, HBV, HCV or HIV.

• History of failure to JAK inhibitor treatment of any inflammatory disease.

• Laboratory values outside of the protocol-defined ranges.

Other protocol-defined Inclusion/Exclusion Criteria may apply.