Poster Presentation ESA-SRB-ANZBMS 2024 in conjunction with ENSA

Annual economic burden for patients with familial hypophosphatemia in the United States (#343)

Jerry Li 1 , Elizabeth H Marchlewicz 2 , Danae Black 2 , Hana Schwartz 2 , Yang Zhao 1 , Erik A Imel 3 , Ki Hyon Kim 4 , Tiffany Bamford 5
  1. Kyowa Kirin, Bedminster, USA
  2. Merative, Ann Arbor, USA
  3. Indiana University School of Medicine, Indianapolis, USA
  4. Kyowa Kirin Asia Pacific Ptd Ltd, Singapore
  5. Kyowa Kirin Australia, Sydney, Australia

Aims: Familial hypophosphatemia (FH) commonly results in renal phosphate wasting, which leads to rickets, osteomalacia and other musculoskeletal consequences. X-linked hypophosphatemia, the most common form of FH, may be treated with burosumab. However, the healthcare utilization and economic burden of FH among burosumab-naïve patients has not been characterized in the USA. This study examined healthcare utilization and costs for burosumab-naïve patients with FH, compared with demographically matched controls without FH.

 Methods: Using the Merative™ MarketScan® Commercial and Medicare US administrative claims databases, patients with >1 diagnosis code for FH (ICD10:E83.31) between 1/1/2018-12/31/2021, and continuous database enrollment for 12-months pre-and post-index were identified. The index date was the date of the first FH diagnosis. FH patients were demographically matched 1:3 to non-FH control patients based on age group, sex, geographic region, payer, and index year. Healthcare utilization and costs were assessed in the 12-month post-index period and adjusted to 2021 dollars using the medical care component of the Consumer Price Index. The Charlson Comorbidity index (CCI) score was reported in the 12-month pre-index period as a measure of baseline health status. Results were reported overall and stratified by age.

 Results: Matched burosumab-naïve FH patients (n=570) and non-FH controls (n=1,710) were 57.0% female, 53.0% with an index year in 2018-2019, and with a mean (standard deviation [SD]) age of 47.2 (19.9) and 46.2 (18.3) years (10.4%, 76.2%, and 13.5% were <18, 18-64, and 65+ years respectively). Baseline CCI score was significantly greater among FH patients than controls (1.9 [2.6] vs. 0.2 [0.9], P<0.001). Annual all-cause healthcare utilization, mean number of healthcare visits, and mean healthcare costs were greater among FH patients vs controls (Table). Similar trends were observed among age-stratified FH patients and non-FH controls.

 Conclusions: FH patients incur substantially higher healthcare utilization, costs, and comorbidity burden compared with non-FH controls.66a9f08e2bd20-Figure.JPG