Improvement in quality of life after Asfotase Alfa treatment in adults with Pediatric-onset Hypophosphatasia: data from 5 patient-reported outcome measures

Abstract

Hypophosphatasia (HPP) is a rare inherited metabolic disorder caused by deficient tissue-nonspecific alkaline phosphatase activity. This study assessed the impact of treatment with asfotase alfa on patient-reported outcomes (PROs) in adults with pediatric-onset HPP. A longitudinal telephone-based survey was administered to eligible individuals enrolled in a patient support program. Interviews were conducted at study entry (prior to asfotase alfa initiation) and after 3, 6, and 12 months. PROs—Patient Health Questionnaire-9 [PHQ-9], Work Productivity and Activity Impairment–Specific Health Problem [WPAI:SHP], Patient-Reported Outcomes Measurement Information System 29 [PROMIS-29], and Routine Assessment of Patient Index Data 3 [RAPID3]—were assessed at each time point. Appropriate statistical tests were performed to assess score changes. Among 50 enrolled patients (mean age: 46 years [SD: 15.4]; 80% female; 94% white), 49 were evaluable at 3 months, 44 at 6 months, and 29 at 12 months. By Month 3, statistically significant improvements from baseline were detected in PHQ-9 scores (10.6 vs. 5.8 [p < 0.0001]), PROMIS-29 domain scores (overall physical function: 38.0 vs. 43.0 [p = 0.001]; anxiety: 57.5 vs. 51.5 [p = 0.0011]; fatigue: 63.3 vs. 55.3 [p < 0.0001]; sleep disturbances: 58.8 vs. 54.3 [p = 0.0099]; ability to participate in social roles and activities: 42.6 vs. 47.7 [p = 0.0012]; and pain interference: 63.8 vs. 58.4 [p = 0.001]) and RAPID3 domain scores (functional status: 2.7 vs. 1.1 [p < 0.0001]; pain tolerance: 6.0 vs. 3.2 [p < 0.0001]; and global health estimate: 5.1 vs. 2.7 [p < 0.0001]). Improvements persisted at Month 12. Patients also showed improvements in WPAI:SHP domain scores at Month 6 (presenteeism: 39.6% vs. 14.1% [p < 0.0001] and work productivity loss: 41.9% vs. 14.1% [p < 0.0001]). Treatment with asfotase alfa was associated with improved quality of life across several domains.