The Impact of Pabinafusp Alfa on the Disease Burden in Hunter's Syndrome: Patient-Reported Outcomes

Abstract

Severe mucopolysaccharidosis type II (MPS-II) patients present with progressive mental impairment and reduced life expectancy. While current available treatment cannot cross the blood–brain barrier, the enzyme replacement therapy with pabinafusp alfa (a recombinant iduronate-2-sulfatase fused to an antihuman transferrin receptor antibody) was designed to penetrate it using transferrin receptor-mediated transcytosis. In this cross-sectional retrospective study, we aimed to report the impact of this new therapy using patient-reported outcomes. Data were collected using standardized questionnaire replied by patients or their caregivers (as proxies). Nine patients received intravenous administration of pabinafusp alfa for at least 104 weeks. All patient showed improvements in behavior (mainly aggressiveness), speech, motor ability, muscle strength, facial expression, breathing, and cognitive skills. Gait improvement was also found in 78% of participants. Caregivers also reported improvements in emotion demonstration as ability to smile, establish eye contact, and give hugs. Collectively, our results indicate a positive impact of pabinafusp alfa on quality of life of individuals with MPS-II and their relatives/caregivers. Future studies are warranted to elucidate the mechanisms underlying these beneficial effects.

Keywords

mucopolysaccharidosis - Hunter's syndrome - enzyme replacement therapy - pabinafusp alfa - behavior - quality of life

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