UTILITY GENERATION FOR SANFILIPPO SYNDROME TYPE A (MPS IIIA) USING HEALTH-STATE VIGNETTES
Author(s)
Simon Dawson, BSc1, Gemma Shields, BSc, MPH, PhD2, Adam Gibson, MSc, PhD2, Georges Dwyer, MSc2, Jasmine Farrington, PhD3, Manpreet K. Sidhu, PhD, MBA4, Louise Longworth, BSc, MSc, PhD2, Jennifer Audi, PharmD5.
1Ultragenyx Pharmaceutical Inc., Sollentuna, Sweden, 2Arrow Health Economics, London, United Kingdom, 3Arrow Health Economics, Oxford, United Kingdom, 4Ultragenyx Pharmaceutical Inc., Novato, CA, USA, 5Ultragenyx Pharmaceutical Inc., Basel, Switzerland.
1Ultragenyx Pharmaceutical Inc., Sollentuna, Sweden, 2Arrow Health Economics, London, United Kingdom, 3Arrow Health Economics, Oxford, United Kingdom, 4Ultragenyx Pharmaceutical Inc., Novato, CA, USA, 5Ultragenyx Pharmaceutical Inc., Basel, Switzerland.
OBJECTIVES: Sanfilippo syndrome type A (MPS IIIA) is an ultra-rare childhood-onset neuronopathic, lysosomal storage disorder characterised by progressive developmental decline. Children with MPS IIIA typically experience apparently normal early development followed by deterioration in cognitive, communication, and motor abilities, and severely premature mortality, typically during adolescence. This study aimed to develop and value health-state vignettes to generate health utility estimates for patients with MPS IIIA.
METHODS: A literature review was conducted to identify key symptoms and health-related quality of life (HRQoL) impacts associated with MPS IIIA and inform the development of a semi-structured interview guide. Interviews were conducted via videoconference with UK clinical experts (n=3) to explore patient and caregiver burden across disease progression. Interview transcripts were analysed using content and thematic analysis, and findings were used to develop draft health-state vignettes. The vignettes were refined and validated through interviews with an additional UK clinical expert (n=1) and caregivers of children with MPS IIIA (n=4).
RESULTS: Six patient vignettes were developed to represent distinct stages of disease progression. Each vignette described the patient's physical symptoms, cognitive and communication abilities, behavioural and psychological impacts, and treatment and care needs, providing a representation of disease burden at each health state. Three caregiver vignettes were developed and included the mental and physical effects on caregivers and families.
CONCLUSIONS: The vignettes highlight the substantial impact of MPS IIIA on the health-related quality of life of both patients and caregivers. They capture the disease progression of this neurodegenerative disorder, from earlier health states characterised by communication challenges, physical effects (e.g. infections), and behavioural and psychological impacts (e.g. hyperactivity and frustration); to end-stage disease, where patients are immobile and in a vegetative state. The vignettes will be valued by 1,000 members of the general population using EQ-5D to generate utility values for a UK cost-effectiveness model.
METHODS: A literature review was conducted to identify key symptoms and health-related quality of life (HRQoL) impacts associated with MPS IIIA and inform the development of a semi-structured interview guide. Interviews were conducted via videoconference with UK clinical experts (n=3) to explore patient and caregiver burden across disease progression. Interview transcripts were analysed using content and thematic analysis, and findings were used to develop draft health-state vignettes. The vignettes were refined and validated through interviews with an additional UK clinical expert (n=1) and caregivers of children with MPS IIIA (n=4).
RESULTS: Six patient vignettes were developed to represent distinct stages of disease progression. Each vignette described the patient's physical symptoms, cognitive and communication abilities, behavioural and psychological impacts, and treatment and care needs, providing a representation of disease burden at each health state. Three caregiver vignettes were developed and included the mental and physical effects on caregivers and families.
CONCLUSIONS: The vignettes highlight the substantial impact of MPS IIIA on the health-related quality of life of both patients and caregivers. They capture the disease progression of this neurodegenerative disorder, from earlier health states characterised by communication challenges, physical effects (e.g. infections), and behavioural and psychological impacts (e.g. hyperactivity and frustration); to end-stage disease, where patients are immobile and in a vegetative state. The vignettes will be valued by 1,000 members of the general population using EQ-5D to generate utility values for a UK cost-effectiveness model.
Conference/Value in Health Info
2026-11, ISPOR Europe 2026, Vienna, Austria
Value in Health, Volume 29, Issue 12S
Code
PCR250
Topic
Patient-Centered Research
Topic Subcategory
Health State Utilities
Disease
Neurological Disorders, Rare & Orphan Diseases