A study to examine the efficacy of KRN23 on bone quality

Phase 1

• Conditions: XLH is a disorder of hypophosphatemia, renal phosphate wasting, and the most common inheritable form of rickets. In XLH patients, excess circulating fibroblast growth factor (FGF23) impair phosphate reabsorption in the kidney. Chronic low serum phosphorus levels lead to defective bone mineralization and, consequently, to rickets in children and osteomalacia in adults, the two major pathologic outcomes of the hypophosphatemia.; MedDRA version: 19.0 Level: LLT Classification code 10016206 Term: Familial hypophosphataemic rickets System Organ Class: 100000004850; Therapeutic area: Body processes [G] - Bones and nerves physological processes [G11]

• Registration Number: EUCTR2015-001775-41-FR
• Lead Sponsor: ltragenyx Pharmaceutical Inc.

Brief Summary

Not available

Detailed Description

Not available

Study Timeline

• Results First Posted: 1900-01-01
• Study Start: 2016-12-13
• Last Update Posted: 10 December 2019

Recruitment & Eligibility

• Status: ot Recruiting
• Sex: Not specified
• Target Recruitment: 10

Inclusion Criteria

Individuals eligible to participate in this study must meet all of the following criteria:
1) Male or female, aged 25 - 65 years, inclusive
2) Diagnosis of XLH supported by classic clinical features of adult XLH (such as short stature or bowed legs), and at least ONE of the following at Screening:
· Documented PHEX mutation in the patient or a directly related family
member with appropriate X-linked inheritance
· Serum iFGF23 level > 30 pg/mL by Kainos assay
3) Biochemical findings consistent with XLH based on overnight fasting (min. 8 hours):
· Serum phosphorus < 2.5 mg/dL at Screening
· TmP/GFR < 2.5 mg/dL at Screening
4) Presence of skeletal pain attributed to XLH/osteomalacia, as defined by a score of = 4 on the Brief Pain Inventory question 3 (BPI-Q3, Worst Pain) at Screening.
(Skeletal pain that, in the opinion of the investigator, is attributed solely to causes
other than XLH/osteomalacia—for example, back pain or joint pain in the presence of
severe osteoarthritis by radiograph in that anatomical location—in the absence of any
skeletal pain likely attributed to XLH/osteomalacia should not be considered for
eligibility.)
5) Estimated glomerular filtration rate (eGFR) = 60 mL/min (using the Chronic Kidney
Disease Epidemiology Collaboration [CKD-EPI] equation) or eGFR of 45-60 mL/min at Screening with confirmation that the renal insufficiency is not due to nephrocalcinosis
6) Provide written informed consent after the nature of the study has been explained, and prior to any research-related procedures
7) Willing to provide access to prior medical records for the collection of biochemical
and radiographic data and disease history
8) Females of child-bearing potential must have a negative urine pregnancy test at
Screening and be willing to have additional pregnancy tests during the study.
Females considered not to be of childbearing potential include those who have been
in menopause for at least two years prior to Screening, or have had tubal ligation at
least one year prior to Screening, or have had a total hysterectomy or bilateral
salpingo-oophorectomy.
9) Participants of child-bearing potential or with partners of child-bearing potential who have not undergone a bilateral salpingo-oophorectomy and are sexually active must consent to use an effective method of contraception as determined by the site
investigator (i.e. oral hormonal contraceptives, patch hormonal contraceptives,
vaginal ring, intrauterine device, physical double-barrier methods, surgical hysterectomy, vasectomy, tubal ligation, or true abstinence) from the period following the signing of the informed consent through 12 weeks after last dose of study drug
10) Must, in the opinion of the investigator, be willing and able to complete all aspects of the study, adhere to the study visit schedule and comply with the assessments
Are the trial subjects under 18? no
Number of subjects for this age range:
F.1.2 Adults (18-64 ye

Exclusion Criteria

Individuals who meet any of the following exclusion criteria will not be eligible to participate in the study:
1) Use of any pharmacologic vitamin D metabolite or analog (e.g. calcitriol,
doxercalciferol, and paricalcitol) within the 2 years prior to Screening
2) Use of oral phosphate within the 2 years prior to Screening
3) Use of aluminum hydroxide antacids, acetazolamides, and thiazides within 7 days
prior to Screening
4) Use of oral bisphosphonates for 6 months or more in the 2 years prior to Screening
5) Chronic use of systemic corticosteroids defined as more than 10 days in the 2 months prior to Screening
6) Corrected serum calcium level = 10.8 mg/dL (2.7 mmol/L) at Screening
7) Serum iPTH = 1.5 times the upper limit of normal (ULN) at Screening
8) Use of medication to suppress PTH (cinacalcet for example) within 60 days prior to
Screening
9) Prothrombin time/Partial thromboplastin time (PT/PTT) outside the normal range at Screening
10) Evidence of any disease or use of anticoagulant medication (such as warfarin,
heparin, direct thrombin inhibitors, or xabans that, in the opinion of the investigator,
cannot be discontinued) that may increase the risk of bleeding during the biopsy
procedure
11) Pregnant or breastfeeding at Screening or planning to become pregnant (self or
partner) at any time during the study
12) Unable or unwilling to withhold prohibited medications throughout the study
13) Documented dependence on narcotics
14) Use of KRN23, or any other therapeutic monoclonal antibody within 90 days prior to Screening
15) Use of investigational product or investigational medical device within 30 days prior to Screening, or requirement for any investigational agent prior to completion of all scheduled study assessments.
OR, in Japan, use of any investigational product or investigational medical device
within 4 months prior to Screening, or requirement for any investigational agent prior
to completion of all scheduled study assessments.
16) Presence or history of any hypersensitivity, allergic or anaphylactic reactions to any monoclonal antibody or KRN23 excipients that, in the judgment of the investigator, places the subject at increased risk for adverse effects
17) History of allergic reaction or adverse reactions to tetracycline
18) Prior history of positive test for human immunodeficiency virus antibody, hepatitis B surface antigen, and/or hepatitis C antibody
19) History of recurrent infection or predisposition to infection, or of known
immunodeficiency
20) Presence of malignant neoplasm (except basal cell carcinoma)
21) Presence of a concurrent disease or condition that would interfere with study
participation or affect safety
22) Presence or history of any condition that, in the view of the investigator, places the subject at high risk of poor treatment compliance or of not completing the study

Study & Design

• Study Type: Interventional clinical trial of medicinal product
• Study Design: Not specified