Trial Outcomes & Findings for Safety, Efficacy, PK and PD of CTAP101 (Calcifediol) ER Capsules for SHPT in HD Patients VDI (NCT NCT03602261)

Last Updated: 2025-03-30

Results Overview

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.

Recruitment status

TERMINATED

Study phase

PHASE2

Target enrollment

44 participants

Primary outcome timeframe

26 weeks

Results posted on

2025-03-30

Participant Flow

Participant milestones

Participant milestones
Measure	CTAP101 Capsules 900mcg/Weekly CTAP101 Oral Capsules/Calcifediol, calcidiol, 25-hydroxyvitamin D3, 900mcg/weekly for 26 weeks Calcifediol Oral Capsule: Capsule, weekly	Placebo Capsules Weekly Placebo Oral Capsules/weekly for 26 weeks Placebo oral capsule: Capsule, weekly
Overall Study STARTED	33	11
Overall Study COMPLETED	25	8
Overall Study NOT COMPLETED	8	3

Reasons for withdrawal

Reasons for withdrawal
Measure	CTAP101 Capsules 900mcg/Weekly CTAP101 Oral Capsules/Calcifediol, calcidiol, 25-hydroxyvitamin D3, 900mcg/weekly for 26 weeks Calcifediol Oral Capsule: Capsule, weekly	Placebo Capsules Weekly Placebo Oral Capsules/weekly for 26 weeks Placebo oral capsule: Capsule, weekly
Overall Study Adverse Event	5	1
Overall Study Physician Decision	1	0
Overall Study Withdrawal by Subject	1	1
Overall Study Lack of Efficacy	0	1
Overall Study Subject moving out of state	1	0

Baseline Characteristics

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

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	CTAP101 Capsules 900mcg/Weekly n=28 Participants CTAP101 Oral Capsules/Calcifediol, calcidiol, 25-hydroxyvitamin D3, 900mcg/weekly for 26 weeks Calcifediol Oral Capsule: Capsule, weekly	Placebo Capsules Weekly n=9 Participants Placebo Oral Capsules/weekly for 26 weeks Placebo oral capsule: Capsule, weekly	Total n=37 Participants Total of all reporting groups
Age, Customized < 65 years old	21 Participants n=93 Participants	7 Participants n=4 Participants	28 Participants n=27 Participants
Age, Customized >= 65 years old	7 Participants n=93 Participants	2 Participants n=4 Participants	9 Participants n=27 Participants
Sex: Female, Male Female	12 Participants n=93 Participants	5 Participants n=4 Participants	17 Participants n=27 Participants
Sex: Female, Male Male	16 Participants n=93 Participants	4 Participants n=4 Participants	20 Participants n=27 Participants
Ethnicity (NIH/OMB) Hispanic or Latino	5 Participants n=93 Participants	4 Participants n=4 Participants	9 Participants n=27 Participants
Ethnicity (NIH/OMB) Not Hispanic or Latino	23 Participants n=93 Participants	5 Participants n=4 Participants	28 Participants n=27 Participants
Ethnicity (NIH/OMB) Unknown or Not Reported	0 Participants n=93 Participants	0 Participants n=4 Participants	0 Participants n=27 Participants
Race (NIH/OMB) American Indian or Alaska Native	0 Participants n=93 Participants	0 Participants n=4 Participants	0 Participants n=27 Participants
Race (NIH/OMB) Asian	1 Participants n=93 Participants	0 Participants n=4 Participants	1 Participants n=27 Participants
Race (NIH/OMB) Native Hawaiian or Other Pacific Islander	0 Participants n=93 Participants	0 Participants n=4 Participants	0 Participants n=27 Participants
Race (NIH/OMB) Black or African American	20 Participants n=93 Participants	5 Participants n=4 Participants	25 Participants n=27 Participants
Race (NIH/OMB) White	7 Participants n=93 Participants	4 Participants n=4 Participants	11 Participants n=27 Participants
Race (NIH/OMB) More than one race	0 Participants n=93 Participants	0 Participants n=4 Participants	0 Participants n=27 Participants
Race (NIH/OMB) Unknown or Not Reported	0 Participants n=93 Participants	0 Participants n=4 Participants	0 Participants n=27 Participants

PRIMARY outcome

Timeframe: 26 weeks

Population: mITT population.

Outcome measures

Outcome measures
Measure	CTAP101 Capsules 900mcg/Weekly n=28 Participants CTAP101 Oral Capsules/Calcifediol, calcidiol, 25-hydroxyvitamin D3, 900mcg/weekly for 26 weeks Calcifediol Oral Capsule: Capsule, weekly	Placebo Capsules Weekly n=9 Participants Placebo Oral Capsules/weekly for 26 weeks Placebo oral capsule: Capsule, weekly
Number of Participants With Response During Efficacy Assessment Period	4 Participants	0 Participants

PRIMARY outcome

Timeframe: 26 weeks

Population: mITT population.

Summary of participants with mean serum total 25-hydroxyvitamin D ≥50 ng/mL at the end of treatment

Outcome measures

Outcome measures
Measure	CTAP101 Capsules 900mcg/Weekly n=28 Participants CTAP101 Oral Capsules/Calcifediol, calcidiol, 25-hydroxyvitamin D3, 900mcg/weekly for 26 weeks Calcifediol Oral Capsule: Capsule, weekly	Placebo Capsules Weekly n=9 Participants Placebo Oral Capsules/weekly for 26 weeks Placebo oral capsule: Capsule, weekly
Total 25-hydroxyvitamin D Response Analysis During Efficacy Period	28 Participants	1 Participants

PRIMARY outcome

Timeframe: 26 weeks

Population: mITT population.

Summary of participants who experienced a reduction in mean plasma iPTH by greater than 30% from the pre-treatment baseline

Outcome measures

Outcome measures
Measure	CTAP101 Capsules 900mcg/Weekly n=28 Participants CTAP101 Oral Capsules/Calcifediol, calcidiol, 25-hydroxyvitamin D3, 900mcg/weekly for 26 weeks Calcifediol Oral Capsule: Capsule, weekly	Placebo Capsules Weekly n=9 Participants Placebo Oral Capsules/weekly for 26 weeks Placebo oral capsule: Capsule, weekly
Number of Participants With Intact Parathyroid Hormone (iPTH) Response During Efficacy Assessment Period	4 Participants	0 Participants

PRIMARY outcome

Timeframe: 0, 4, 8, 12, 16, 20, 24, 30, 36, 42 and 48 hours post-dose (single and repeat dose)

Population: PK population. 6 subjects did not complete the repeat PK dosing.

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)

Outcome measures

Outcome measures
Measure	CTAP101 Capsules 900mcg/Weekly n=18 Participants CTAP101 Oral Capsules/Calcifediol, calcidiol, 25-hydroxyvitamin D3, 900mcg/weekly for 26 weeks Calcifediol Oral Capsule: Capsule, weekly	Placebo Capsules Weekly Placebo Oral Capsules/weekly for 26 weeks Placebo oral capsule: Capsule, weekly
Pharmacokinetic (PK) Profile (Cmax) of Serum Calcifediol Cmax (single PK)	45.5 ng/mL Standard Deviation 20.17	—
Pharmacokinetic (PK) Profile (Cmax) of Serum Calcifediol Cmax (repeat PK)	181.0 ng/mL Standard Deviation 171.92	—

PRIMARY outcome

Timeframe: 0, 4, 8, 12, 16, 20, 24, 30, 36, 42 and 48 hours post-dose (single and repeat dose)

Population: PK population. 6 subjects did not complete the repeat PK dosing.

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)

Outcome measures

Outcome measures
Measure	CTAP101 Capsules 900mcg/Weekly n=18 Participants CTAP101 Oral Capsules/Calcifediol, calcidiol, 25-hydroxyvitamin D3, 900mcg/weekly for 26 weeks Calcifediol Oral Capsule: Capsule, weekly	Placebo Capsules Weekly Placebo Oral Capsules/weekly for 26 weeks Placebo oral capsule: Capsule, weekly
Pharmacokinetic (PK) Profile (Tmax) of Serum Calcifediol Tmax (single PK)	0.6 hours Standard Deviation 0.41	—
Pharmacokinetic (PK) Profile (Tmax) of Serum Calcifediol Tmax (repeat PK)	2.5 hours Standard Deviation 2.72	—

PRIMARY outcome

Timeframe: 0, 4, 8, 12, 16, 20, 24, 30, 36, 42 and 48 hours post-dose (single and repeat dose)

Population: PK population. 6 subjects did not complete the repeat PK dosing.

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)

Outcome measures

Outcome measures
Measure	CTAP101 Capsules 900mcg/Weekly n=18 Participants CTAP101 Oral Capsules/Calcifediol, calcidiol, 25-hydroxyvitamin D3, 900mcg/weekly for 26 weeks Calcifediol Oral Capsule: Capsule, weekly	Placebo Capsules Weekly Placebo Oral Capsules/weekly for 26 weeks Placebo oral capsule: Capsule, weekly
Pharmacokinetic (PK) Profile (AUC0-t) of Serum Calcifediol AUC0-t (single PK)	9118.4 hour x ng/mL Standard Deviation 3557.65	—
Pharmacokinetic (PK) Profile (AUC0-t) of Serum Calcifediol AUC0-t (repeat PK)	95820.7 hour x ng/mL Standard Deviation 44858.77	—

SECONDARY outcome

Timeframe: 26 weeks

Population: mITT population.

Effect of CTAP101 on 1,25-dihydroxyvitamin D

Outcome measures

Outcome measures
Measure	CTAP101 Capsules 900mcg/Weekly n=28 Participants CTAP101 Oral Capsules/Calcifediol, calcidiol, 25-hydroxyvitamin D3, 900mcg/weekly for 26 weeks Calcifediol Oral Capsule: Capsule, weekly	Placebo Capsules Weekly n=9 Participants Placebo Oral Capsules/weekly for 26 weeks Placebo oral capsule: Capsule, weekly
Pharmacodynamic Analysis of 1,25-dihydroxyvitamin D Baseline	9.4 pg/mL Standard Error 1.2	12.6 pg/mL Standard Error 2.7
Pharmacodynamic Analysis of 1,25-dihydroxyvitamin D Visit 24	50.7 pg/mL Standard Error 7.8	13.4 pg/mL Standard Error 4.1

Adverse Events

CTAP101 Capsules 900mcg/Weekly

Serious events: 15 serious events

Other events: 29 other events

Deaths: 0 deaths

Placebo Capsules Weekly

Serious events: 4 serious events

Other events: 9 other events

Deaths: 0 deaths

Serious adverse events

Other adverse events

Additional Information

Akhtar Ashfaq

OPKO Health

Phone: 305-575-423

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee
Publication restrictions are in place

Measure	CTAP101 Capsules 900mcg/Weekly n=32 participants at risk CTAP101 Oral Capsules/Calcifediol, calcidiol, 25-hydroxyvitamin D3, 900mcg/weekly for 26 weeks Calcifediol Oral Capsule: Capsule, weekly	Placebo Capsules Weekly n=11 participants at risk Placebo Oral Capsules/weekly for 26 weeks Placebo oral capsule: Capsule, weekly
Infections and infestations Corona virus infection	9.4% 3/32 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.	9.1% 1/11 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.
Infections and infestations Osteomyelitis	9.4% 3/32 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.	9.1% 1/11 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.
Infections and infestations Pneumonia	0.00% 0/32 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.	9.1% 1/11 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.
Infections and infestations Septic embolus	6.2% 2/32 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.	0.00% 0/11 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.
Infections and infestations Urinary tract infection staphylococcal	0.00% 0/32 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.	9.1% 1/11 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.
Nervous system disorders Presyncope	6.2% 2/32 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.	0.00% 0/11 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.
Nervous system disorders Demyelinating polyneuropathy	0.00% 0/32 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.	9.1% 1/11 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.
Nervous system disorders Dizziness	3.1% 1/32 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.	0.00% 0/11 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.
Nervous system disorders Paraplegia	3.1% 1/32 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.	0.00% 0/11 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.
Nervous system disorders Seizure	3.1% 1/32 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.	0.00% 0/11 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.
Cardiac disorders Acute coronary syndrome	3.1% 1/32 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.	0.00% 0/11 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.
Cardiac disorders Angina pectoris	3.1% 1/32 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.	0.00% 0/11 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.
Cardiac disorders Atrial fibrillation	0.00% 0/32 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.	9.1% 1/11 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.
Cardiac disorders Bradycardia	0.00% 0/32 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.	9.1% 1/11 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.
Cardiac disorders Cardiac arrest	0.00% 0/32 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.	9.1% 1/11 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.
Cardiac disorders Cardiac failure congestive	3.1% 1/32 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.	0.00% 0/11 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.
Cardiac disorders Cardio-respiratory arrest	3.1% 1/32 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.	0.00% 0/11 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.
Injury, poisoning and procedural complications Arteriovenous fistula site haematoma	3.1% 1/32 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.	0.00% 0/11 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.
Injury, poisoning and procedural complications Arteriovenous fistula thrombosis	3.1% 1/32 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.	0.00% 0/11 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.
Injury, poisoning and procedural complications Incision site complication	0.00% 0/32 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.	9.1% 1/11 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.
Injury, poisoning and procedural complications Subdural haematoma	3.1% 1/32 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.	0.00% 0/11 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.
Metabolism and nutrition disorders Fluid overload	6.2% 2/32 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.	0.00% 0/11 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.
Metabolism and nutrition disorders Hyperkalaemia	3.1% 1/32 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.	0.00% 0/11 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.
Gastrointestinal disorders Gastrointestinal haemorrhage	3.1% 1/32 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.	9.1% 1/11 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.
Respiratory, thoracic and mediastinal disorders Hypoxia	6.2% 2/32 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.	0.00% 0/11 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.
Respiratory, thoracic and mediastinal disorders Chronic obstructive pulmonary disease	3.1% 1/32 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.	0.00% 0/11 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.
Respiratory, thoracic and mediastinal disorders Dyspnoea	3.1% 1/32 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.	0.00% 0/11 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.
Vascular disorders Hypotension	3.1% 1/32 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.	9.1% 1/11 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.
Musculoskeletal and connective tissue disorders Musculoskeletal chest pain	3.1% 1/32 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.	0.00% 0/11 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.
Renal and urinary disorders Chronic kidney disease	3.1% 1/32 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.	0.00% 0/11 • 26 weeks Safety population. CTAP101 group has 32 subjects and placebo group has 11 subjects who received at least 1 dose.