Safety, Efficacy, PK and PD of CTAP101 (Calcifediol) ER Capsules for SHPT in HD Patients VDI

Phase 2

Terminated

• Conditions: Chronic Kidney Diseases; Secondary Hyperparathyroidism Due to Renal Causes; Stage 5 Chronic Kidney Disease; Vitamin D Deficiency
• Interventions: Drug: Calcifediol Oral Capsule; Drug: Placebo oral capsule

• Registration Number: NCT03602261
• Lead Sponsor: OPKO Health, Inc.

Brief Summary

Safety, Efficacy, PK and PD of CTAP101 (calcifediol) ER Capsules for SHPT in HD Patients VDI

Detailed Description

A Multi-Center, Randomized, Two-Cohort Phase 2 Study to Evaluate the Safety, Efficacy, Pharmacokinetics (PK) and Pharmacodynamics (PD) of CTAP101 (calcifediol) Extended-Release Capsules to Treat Secondary Hyperparathyroidism (SHPT) in Subjects with Vitamin D Insufficiency (VDI) and Chronic Kidney Disease Requiring Regular Hemodialysis.

Study Timeline

• Study Start: 2018-07-09
• Study First Submitted: 2018-07-13
• Study First Submitted QC: 2018-07-25
• Study First Posted: 2018-07-26
• Primary Completion: 2021-02-24
• Study Completion: 2021-02-24
• Results First Submitted: 2025-02-14
• Status Verified: 2025-03
• Results First Submitted QC: 2025-03-12
• Last Update Submitted: 2025-03-12
• Results First Posted: 2025-03-30
• Last Update Posted: 2025-03-30

Recruitment & Eligibility

• Status: TERMINATED
• Sex: All
• Target Recruitment: 44

Inclusion Criteria

Each subject must meet the following criteria to be enrolled in this study:

1. Be at least 18 years of age.

2. Be diagnosed with CKD requiring in-center HD tiw for the preceding 6 months, as confirmed by medical history.

3. Be without any disease state or physical condition that might impair evaluation of safety or which, in the investigator's opinion, would interfere with study participation, including:

   1. Serum albumin ≤ 3.0 g/dL; and,
   2. Serum transaminase (alanine transaminase [ALT], glutamic pyruvic transaminase [SGPT], aspartate aminotransferase [AST] or glutamic oxaloacetic transaminase [SGOT]) > 2.5 times the upper limit of normal at screening.

4. Be receiving calcimimetic therapy (either etelcalcetide or cinacalcet) and/or calcitriol or other 1α-hydroxylated vitamin D analog (paricalcitol or doxercalciferol) for at least 1 month at the time of screening for enrollment. Approximately 50% of enrolled subjects will have been receiving calcimimetic therapy.

5. Exhibit during the initial screening visit:

   1. Plasma immunoreactive parathyroid hormone (iPTH) ≥150 pg/mL and <600 pg/mL if receiving etelcalcetide, cinacalcet, calcitriol or other 1α-hydroxylated vitamin D analog (paricalcitol or doxercalciferol); or
   2. Plasma iPTH ≥300 pg/mL and <900 pg/mL if not receiving etelcalcetide, cinacalcet, calcitriol or other 1α-hydroxylated vitamin D analog; and,
   3. Serum total 25-hydroxyvitamin D <30 ng/mL if not receiving vitamin D supplementation.

6. When otherwise confirmed eligible at Visit 1, must forgo any further treatment with etelcalcetide and cinacalcet for the duration of the study and undergo an 8-week washout period.

7. When otherwise confirmed eligible at Visit 1, must forgo any further treatment with calcitriol or other 1α-hydroxylated vitamin D analogs or vitamin D supplements for the duration of the study and undergo an 8-week washout period.

8. Exhibit after the 8-week washout period (if required due to prior use of etelcalcetide, cinacalcet, calcitriol or other 1α-hydroxylated vitamin D analogs, or vitamin D supplementation):

   1. Plasma iPTH increased by at least 50%;
   2. Plasma iPTH ≥300 pg/mL and <1,200 pg/mL;
   3. Corrected serum calcium <9.8 mg/dL;
   4. Serum total 25-hydroxyvitamin D <50 ng/mL; and,
   5. Serum phosphorus <6.5 mg/dL.

9. When otherwise confirmed eligible at Visit 1, if taking more than 1,000 mg per day of elemental calcium, reduce calcium use (to ≤1,000 mg per day) and/or use non-calcium based phosphate binder therapies (as needed) for the duration of the study.

10. When otherwise confirmed eligible at Visit 1, if taking bone metabolism therapies that may interfere with study endpoints, must discontinue use of these agents for the duration of the study.

11. Willing and able to comply with study instructions and commit to all clinic visits for the duration of the study.

12. Female subjects of childbearing potential must be neither pregnant nor lactating and must have a negative serum beta-human chorionic gonadotropin (b-hCG) pregnancy test at the first screening visit and at other scheduled times.

13. All female subjects of childbearing potential and male subjects with female partners of childbearing potential must agree to use effective contraception (eg, implants, injectables, combined oral contraceptives, intrauterine device, sexual abstinence, vasectomy or vasectomized partner) for the duration of the study.

14. Be able to read, understand and sign the subject Informed Consent Form (ICF) or have a legal representative sign the ICF.

4.3 Exclusion Criteria

Subjects who meet any of the following criteria will be excluded from the study:

1. Scheduled kidney transplant or parathyroidectomy.

2. History (prior 2 months) of corrected serum calcium ≥9.8 mg/dL or serum phosphorus

   ≥6.5 mg/dL if not receiving calcitriol or other 1α-hydroxylated vitamin D analog.

3. Receipt of bisphosphonate therapy or other bone modifying treatment (eg, denosumab) within 6 months prior to enrollment.

4. Known previous or concomitant serious illness or medical condition, such as malignancy, human immunodeficiency virus, significant gastrointestinal or hepatic disease, intestinal malabsorption disorder, hepatitis or cardiovascular event that in the opinion of the investigator may worsen or reduce life expectancy, and/or interfere with participation in the study.

5. History of neurological/psychiatric disorder, including psychotic disorder or dementia, or any reason which, in the opinion of the investigator makes adherence to a treatment or follow-up schedule unlikely.

6. Known or suspected hypersensitivity to any of the constituents of the study drugs.

7. Currently participating in, or has participated in, an interventional/investigational study within 30 days prior to study screening.

Exclusion Criteria

Not provided

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
CTAP101 Capsules 900mcg/weekly	Calcifediol Oral Capsule	CTAP101 Oral Capsules/Calcifediol, calcidiol, 25-hydroxyvitamin D3, 900mcg/weekly for 26 weeks
Placebo Capsules weekly	Placebo oral capsule	Placebo Oral Capsules/weekly for 26 weeks

Primary Outcome Measures

Name	Time	Method
Number of Participants With Response During Efficacy Assessment Period	26 weeks	To evaluate the efficacy of repeated dosing with 900 mcg per week of CTAP101 extended release (ER) Capsules versus placebo in raising mean serum total 25-hydroxyvitamin D (25D) to ≥50 ng/mL and in reducing mean plasma intact parathyroid hormone (iPTH) by at least 30% from pre-treatment baseline.
Total 25-hydroxyvitamin D Response Analysis During Efficacy Period	26 weeks	Summary of participants with mean serum total 25-hydroxyvitamin D ≥50 ng/mL at the end of treatment
Number of Participants With Intact Parathyroid Hormone (iPTH) Response During Efficacy Assessment Period	26 weeks	Summary of participants who experienced a reduction in mean plasma iPTH by greater than 30% from the pre-treatment baseline
Pharmacokinetic (PK) Profile (Cmax) of Serum Calcifediol	0, 4, 8, 12, 16, 20, 24, 30, 36, 42 and 48 hours post-dose (single and repeat dose)	To assess Cmax of serum calcifediol after a single dose of 900 mcg at the start of the study (Single Dose PK Period), and a repeat dose of 300 mcg at the end of the study (Repeat Dose PK Period)
Pharmacokinetic (PK) Profile (Tmax) of Serum Calcifediol	0, 4, 8, 12, 16, 20, 24, 30, 36, 42 and 48 hours post-dose (single and repeat dose)	To assess Tmax of serum calcifediol after a single dose of 900 mcg at the start of the study (Single Dose PK Period), and a repeat dose of 300 mcg at the end of the study (Repeat Dose PK Period)
Pharmacokinetic (PK) Profile (AUC0-t) of Serum Calcifediol	0, 4, 8, 12, 16, 20, 24, 30, 36, 42 and 48 hours post-dose (single and repeat dose)	To assess AUC0-t of serum calcifediol after a single dose of 900 mcg at the start of the study (Single Dose PK Period), and a repeat dose of 300 mcg at the end of the study (Repeat Dose PK Period)

Secondary Outcome Measures

Name	Time	Method
Pharmacodynamic Analysis of 1,25-dihydroxyvitamin D	26 weeks	Effect of CTAP101 on 1,25-dihydroxyvitamin D

Trial Locations

Locations (15)

Research by Design, LLC; 🇺🇸 Chicago, Illinois, United States

Northshore University Health; 🇺🇸 Evanston, Illinois, United States

Southwest Houston Research LTD; 🇺🇸 Houston, Texas, United States

Kidney & Hypertension Specialists; 🇺🇸 San Antonio, Texas, United States

Laurel Canyon Dialysis, LLC; 🇺🇸 Sun Valley, California, United States

Southwest MS Nephrology; 🇺🇸 McComb, Mississippi, United States

North America Research Institute, Inc.; 🇺🇸 San Dimas, California, United States

Long Beach Quest Dialysis Center; 🇺🇸 Long Beach, California, United States

WCCT Global, Inc.; 🇺🇸 Cypress, California, United States

Hacienda Dialysis Center; 🇺🇸 Hacienda Heights, California, United States

California Institute of Renal Research CKD/Dialysis & Transplant Division; 🇺🇸 La Mesa, California, United States

Ontario Dialysis Center; 🇺🇸 Ontario, California, United States

Renal and Transplant Associates of New England; 🇺🇸 Springfield, Massachusetts, United States

AKDHC Medical Research Services; 🇺🇸 Phoenix, Arizona, United States

University of Colorado Denver Anschutz Medical Campus; 🇺🇸 Aurora, Colorado, United States