The main purpose of this multicenter, randomized, double-blind, placebo-controlled Phase 2b study is to investigate the safety and efficacy of GIA632 in participants with NSV and to identify the optimal dose to be promoted into the confirmatory Phase 3 program.

This trial in adult participants ≥ 18 years with non-segmental vitiligo (NSV) consists of a randomized, double-blind, placebo-controlled period to establish and characterize the dose-response relationship of GIA632 and estimate the targeted doses treatment effect compared with placebo, followed by the assessment of longer term safety and efficacy in extension period.

Inclusion Criteria:

• Signed informed consent must be obtained prior to participation in the study
• Male or female as assigned at birth ≥ 18 years of age at the time of screening
• Individuals with a diagnosis of non-segmental vitiligo and confirmation of diagnosis through physical examination by the investigator
• Non-segmental vitiligo, as assessed at screening, as
• ≥ 0.5% Body Surface Area (BSA) on the face and F-VASI score ≥ 0.5
• ≥ 3% BSA on non-facial areas (minimum of 3% should be calculated in addition to hands and feet) and T-VASI score = 3 to 60

Exclusion Criteria:

• Individuals unable or unwilling to follow the study procedures and/or to complete the study-related questionnaires
• Presence of segmental or mixed vitiligo, or other skin comorbidities that may interfere with study assessments (e.g., hypopigmented mycosis fungoides, genetic diseases with pigmentary aberrations [such as piebaldism, Waardenburg, etc.], chemical- or druginduced leukoderma, etc.)
• Previous exposure to biologic drugs directly targeting IL-15 or IL-15 receptors
• Individual who previously attempted or completed depigmentation therapy for NSV
• Use of prohibited medication & treatments. Other protocol-defined inclusion/exclusion criteria may apply

Novartis is committed to sharing with qualified external researchers, access to patient-level data and supporting clinical documents from eligible studies. These requests are reviewed and approved by an independent review panel on the basis of scientific merit. All data provided is anonymized to respect the privacy of patients who have participated in the trial in line with applicable laws and regulations. This trial data availability is according to the criteria and process described on www.clinicalstudydatarequest.com.