Patient Reported Symptomatology in Hypophosphatasia

Presentation Number: MON 338
Date of Presentation: April 3rd, 2017

Christine Moulton Clemson*1, Deborah Fowler2 and Scott Moseley3
1Alexion Pharmaceuticals, Inc.* at time of study, New Haven, CT, 2Soft Bones, Inc., Boonton, NJ, 3Alexion Pharmaceuticals, Inc., New Haven, CT


Hypophosphatasia (HPP) is heterogenic disease with a wide range of signs and symptoms that may be debilitating. The natural history of HPP is poorly understood; patients and their caregivers often question whether specific symptoms are manifestations of the natural course of the disease or are unrelated. In an attempt to design an international survey to be distributed to a broad audience of HPP patients regarding their symptoms, a group of US patients and caregivers were convened to answer a questionnaire developed by Alexion. Patients or their caregivers were asked to describe symptoms experienced by age, and to identify the most problematic symptoms, as well as those of uncertain association with HPP. A total of 14 subjects participated: 9 patients; 4 caregivers, and one identified as both. Ages of patients ranged from 11 months to 70 years old (mean 41 years, median 48 years; n=14). Based on age of onset of symptoms, 9 patients had juvenile HPP (symptoms appeared between seven months and 18 years of age) and 5 had perinatal/infantile onset (symptoms prior to 6 months). Many symptoms known to be associated with the natural history of the disease (e.g. fracture, bone deformity, gait issues) were reported. The most problematic symptoms reported were fractures, bone and muscle pain. However multiple symptoms were commonly reported that previously have not been strongly associated with the disease (e.g. attention deficit, brain fog/cognition, paresthesia, asthma and fatigue). Moreover, previously unreported symptoms were reported as the most problematic for 42% of the patients. These results show that the current description of the natural history of HPP is inadequate. A more inclusive description of the symptoms of HPP may allow for a more robust understanding the disease for patients and caregivers. It may also help inform the medical management of patients by clinicians. Furthermore, these results may inform future clinical trials evaluating therapeutics. The results of this initiative are being incorporated into a robust global patient survey in order to determine the generalizability of these findings to HPP patients worldwide.


Disclosure: CMC: Employee, Alexion Pharmaceuticals, Inc. *at time of study. DF: Research Funding, Alexion Pharmaceuticals, Inc.. SM: Employee, Alexion Pharmaceuticals, Inc..