OBJECTIVES: Alpha-mannosidosis (AM) is an ultra-rare autosomal lysosomal storage disorder affecting approximately 1 in 500,000 live births. To date, there are no studies on the economic burden of AM. The primary aim of this study was to assess the worldwide economic burden of AM.

METHODS: An international online survey was conducted between November 2022 and February 2023 in patients ≥10 years or caregivers of patients with a confirmed diagnosis of AM. The study included untreated patients (may have received hematopoietic stem cell transplantation or bone marrow transplantation) and patients treated with enzyme replacement therapy (ERT). Both qualitative and quantitative analysis were undertaken.

RESULTS: Overall, three patients and 48 caregivers completed the survey from 18 different countries. The median age of patients was 22.3 years (mean 24.2±9.7, range 10.3–45.7); approximately half were male, and half were treated with ERT. In the past 12 months, nearly two thirds (60.9%) of patients visited primary care and a quarter (23.8%) visited more than three times for reasons related to AM. Most patients (87%) did not visit the hospital over the past 12 months. Of the six patients who were hospitalized 1–2 times, reasons include surgeries, allergies, bone fractures, dental treatments, hearing issues and ocular pruritus. Similar number of primary care and hospitalization visits were reported regardless of treatment. Over their lifetime, a quarter (26.7%) of patients reported 2–3 surgeries and a fifth (22.2%) reported 5–10 surgeries due to AM, with three patients reporting more than 10 surgical procedures due to AM.

CONCLUSIONS: There are varying levels of healthcare resource utilization for patients with AM, with several reporting a substantial number of visits during the 12-months pre-interview. This is the first study reporting the economic burden of AM and demonstrates an unmet need for improved disease management in a proportion of AM patients.