Effectiveness of Paricalcitol in Reducing Parathyroid Hormone Levels in X-linked Hypophosphatemic Rickets


Hyperparathyroidism | Hypophosphatemia, Familial

Trial Phase

Trial Purpose and Description

Trial Purpose

The purpose of this study is to determine the effectiveness of paricalcitol, a form of synthetic vitamin D, in lowering parathyroid hormone (PTH) levels and reducing disease symptoms in children and adults with X-linked hypophosphatemic (XLH) rickets.

Participation Guidelines

9 Years and older

Eligibility Criteria

Inclusion Criteria:

  • Diagnosis of XLH rickets
  • Fasting serum calcium of 10.7 mg/dl or less
  • Fasting PTH greater than 40 nleq/ml and less than 120 nleq/ml in the mid-molecule PTH assay at screening (upper limit of normal is 25 nleq/ml)
  • Willing and able to participate in the trial
  • Taking stable dose of standard therapy for XLH rickets for at least 2 months prior to study entry
  • Concomitant therapy for XLH rickets will not be an exclusion criteria
  • Parent or guardian willing to provide informed consent, if applicable

Exclusion Criteria:

  • Concomitant kidney failure (estimated creatinine clearance less than 60 cc/min or serum creatinine greater than 1.5 mg/dl)
  • Serum 25-OH vitamin D less than 20 ng/ml. Participants meeting this criterion will receive vitamin D3 supplementation for 3 months and then be rescreened.
  • Unable to comply with protocol and appropriate follow-up visits
  • Treatment with agents that may affect skeletal metabolism, such as glucocorticoids and anticonvulsants
National Institute of Arthritis & Musculoskeletal & Skin Diseases
National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS)
Yale University
Last Updated:
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