RESUMEN
INTRODUCTION: Vitiligo can be associated with a psychological burden, stigmatization and impaired quality of life. Tools to assess the impact of vitiligo exist; however, none were developed in line with the FDA's patient-reported outcome (PRO) Guidance for Industry. This study aimed to explore the content validity of two newly developed PRO measures to assess the impact of facial and total body vitiligo on how patients feel and function. METHODS: Draft PRO measures were developed from existing literature and input from PRO experts, a patient advocate and a clinical expert. Qualitative interviews were conducted with US participants living with vitiligo and international dermatologists with vitiligo expertise. Concept elicitation methodology explored the relevance of concepts in the draft PRO, while cognitive debriefing assessed conceptual relevance and understanding/interpretation. Items were iteratively amended/added throughout the interview study. RESULTS: The 60 participants included adults (n = 48, 63% female, 18-62 years old) and adolescents (n = 12, 67% female, 12-17 years old) with Fitzpatrick Skin Types I-VI. Expert dermatologists from the US (n = 8), EU (n = 4), India (n = 1) and Egypt (n = 1) participated. Concept elicitation was utilized to confirm the signs/symptoms of vitiligo and the associated impact on emotional/psychological wellbeing, social functioning, daily life and work/school. Conceptual saturation was achieved. Most participants reported impacts on their emotional/psychological wellbeing (n = 57, 95%), e.g. feeling self-conscious (n = 35, 58%). Participants reported impacts on social functioning (n = 53, 88%), e.g. vitiligo being noticed by others (n = 42, 70%). There was general consensus between participants and expert dermatologists. Cognitive debriefing confirmed that the items were well understood. Most items were conceptually relevant; feeling self-conscious and feeling frustrated were highly endorsed. Items were removed based on low conceptual relevance (feeling abandoned, skin roughness) and expected redundancy (four items), resulting in two measures with three proposed domain scores: Emotional/Psychological Wellbeing; Social Functioning; and Physical Sensation. No comprehension concerns were observed in relation to the 7-day recall period or the item response scale/options. Eight dermatologists reviewed the PRO measures, confirming comprehensiveness and relevance. CONCLUSION: The draft Vitiligo Patient Priority Outcomes (ViPPO) measures evaluate the impact of facial (ViPPO-F) and total body (ViPPO-T) vitiligo on emotional/psychological and social functioning. The ViPPO measures are well understood, comprehensive and content valid for adults and adolescents with vitiligo.
RESUMEN
INTRODUCTION: This study explored patients' and dermatologists' priority outcomes for treatment to address, clinical outcome assessments (COA) for use in vitiligo clinical trials, and perceptions of within-patient meaningful change in facial and total body vitiligo. METHODS: Semistructured, individual, qualitative interviews were conducted with patients living with non-segmental vitiligo in the USA and with expert dermatologists in vitiligo. Concept elicitation discussions included open-ended questions to identify patient priority outcomes. Vitiligo COAs were reviewed by dermatologists. Tasks were completed by patients to explore their perceptions of meaningful changes in vitiligo outcomes; dermatologists' opinions were elicited. Data were analyzed using thematic methods; meaningful change tasks were descriptively summarized. RESULTS: Individuals with vitiligo (N = 60) included adults (n = 48, 63% female) and adolescents (n = 12, 67% female). All Fitzpatrick Skin Types were represented. Eight (13%) were first- or second-generation immigrants to the USA. Expert dermatologists (N = 14) participated from the USA (n = 8), EU (n = 4), India (n = 1), and Egypt (n = 1). All individuals with vitiligo reported experiencing skin depigmentation; an observable clinical sign of vitiligo. Most confirmed that lesion surface area (n = 59/60, 98%) and level of pigmentation (n = 53/60, 88%) were important to include in disease assessments. Following an explanation, participants (n = 49/60, 82%) felt that the Facial Vitiligo Area Scoring Index (F-VASI) measurement generally made sense and understood that doctors would use it to assess facial vitiligo. Most participants felt that a 75% (n = 47/59, 80%) or 9 0% improvement in their facial vitiligo would be indicative of treatment success (n = 55/59, 93%). In the context of evaluating a systemic oral treatment for vitiligo, dermatologists perceived a 75% improvement on the F-VASI as successful (n = 9/14, 64%). Regarding the Total VASI (T-VASI) score, n = 30 participants considered 33% improvement as treatment success; an additional n = 10 endorsed 50% improvement and a further n = 5 endorsed 75% improvement. Clinicians most frequently identified 50% (n = 6/14, 43%) or 75% (n = 4/14, 29%) improvement in T-VASI as successful. CONCLUSION: Repigmentation is a priority outcome for patients. The VASI was considered an appropriate tool to assess the extent of vitiligo. A minimum 75% improvement from baseline in the F-VASI and minimum 50% improvement from baseline in the T-VASI were identified as within-patient clinically meaningful thresholds.
