Quality of Life Assessments Utilized in Vitiligo Clinical Trials

Introduction. Vitiligo is an acquired autoimmune disease associated with high psychosocial burden. As novel treatments are being developed in clinical trials, assessing vitiligo disease burden extends beyond physical manifestations. Including quality of life (QoL) measures in vitiligo clinical trials can better capture disease-specific psychosocial concerns and facilitate cross comparisons amongst interventions. Objective. To determine the frequency and types of QoL measures utilized in vitiligo clinical trials and comment on how this has changed longitudinally. Methods. A search of vitiligo clinical trials using clinicaltrials.gov was conducted. Phase 2 and phase 3 trials published in English from January 2000 to July 2023 were eligible for this review. Characteristics of clinical trial parameters were compared to those of non-QoL reporting clinical trials using Pearson’s χ2 tests (or Fisher’s if low n). Results. A total of 60 clinical trials were eligible for this review, of which 40% included a QoL measure in their study design. Phase 3 clinical trials ( $p$ = 0.002), larger (100+ participants) trials ( $p$ = 0.063), U.S. trials ( $p$ = 0.029), and pharmaceutical interventions ( $p$ = 0.022) were more likely to include QoL measures in their design. The number of clinical trials has been increasing over time, with 8 trials from 2000 to 2010, 32 total trials from 2011 to 2020, and 20 trials from 2021 to 2023. The most commonly used QoL measures were the Dermatology Life Quality Index (DLQI, 55.2%), Children's Dermatology Life Quality Index (CDLQI, 13.8%), and Vitiligo-specific quality of life instrument (VitiQoL, 13.8%). Over time, the VitiQoL and CDLQI have been used more frequently. Conclusion. Although vitiligo is associated with high psychological and emotional burden, less than half of vitiligo trials utilize QoL measures. The general dermatology QoL measures, namely the DLQI and CDLQI, are the most commonly used QoL assessments. As the number of clinical trials is increasing, vitiligo-specific questionnaires may better capture unique vitiligo-specific concerns. Standardizing the types of and implementation of QoL questionnaires in clinical trials can aid in assessing outcome measures across clinical trials worldwide and allow for better data interpretation, comparability, and clinical application of results.