A Phase 2, Multicenter, Randomized, Placebo-Controlled, Double-Blind, Dose-Ranging Trial to Evaluate the Efficacy and Safety of Zasocitinib in Participants With Nonsegmental Vitiligo
Vitiligo is a long-term autoimmune condition that causes the skin to lose its color. The body's germ-fighting system (immune system) mistakenly attacks the skin cells (melanocytes) which produce the pigment that gives the skin color (melanin). This leads to the formation of patches of skin with less or no pigment (depigmentation). These patches can occur anywhere on the body. In the nonsegmental form of vitiligo, similar patches occur on both sides of the body (symmetrical patches). The main aim of this study is to learn how safe zasocitinib is, how well it works and how well it is tolerated by adults with nonsegmental vitiligo. The participants will receive the study treatment (either zasocitinib or placebo) for up to 1 year (52 weeks). The placebo looks like the zasocitinib capsule but does not have any medicine in it. Participants who receive placebo at the beginning will change to zasocitinib after about 6 months. During the study, participants will visit their study clinic 11 times.
⁃ Participant willingness:
• Participant is willing and able to understand and fully comply with trial procedures and requirements (including digital tools and applications), in the opinion of the investigator.
• Participant has provided written informed consent and any required privacy authorization before the initiation of any trial procedures.
• Disease Characteristics:
• Participants must have a clinical diagnosis of nonsegmental vitiligo: F-VASI greater than or equal to (\>=) 0.5 and a T-VASI \>= 5 and less than or equal to (\<=) 50 at screening and Day 1.
• Age and Reproductive Status:
• Participant is aged \>=18 years to \<=75 years old at the time of consent.
• Participant meets the following birth control requirement:
• An individual with potential for pregnancy who is now of nonchildbearing potential with laboratory confirmation of postmenopausal status; or, if sexually active with a nonsterilized individual who produces sperm, an individual with potential for pregnancy who agrees to use a highly effective method of contraception from the signing of informed consent throughout the duration of the trial. The use of effective contraception will be required for assigned male sex at birth participants. In the European Union (EU) / European Economic Area (EEA) and the United Kingdom (UK), for participants who elect to use hormonal contraception as a form of highly effective contraception, the investigator must document a favorable benefit-risk assessment to justify the participant's inclusion in the trial at screening and every 3 months during the trial.
• For participants in the EU/EEA or UK, the investigator must have no reason to believe that the participant would be placed at risk by participating in the trial with regard to the European Commission decision as of 10 March 2023 on measures to minimize risk of serious side effects with Janus Kinase inhibitor (JAKi) (EMA/142279/2023) and the UK MHRA guideline on JAKi: new measures to reduce risks of major cardiovascular events, malignancy, venous thromboembolism, serious infections and increased mortality as of 26 April 2023 (Drug Safety Update volume 16, issue 9).