Trial Outcomes & Findings for Daily Vitamin D for Sickle-cell Respiratory Complications (NCT NCT04170348)
NCT ID: NCT04170348
Last Updated: 2025-09-24
Results Overview
Respiratory events will be calculated as the sum of respiratory infection, asthma exacerbation, and acute chest syndrome, as ascertained by use of a validated questionnaire.
COMPLETED
PHASE2
58 participants
Month 12, Month 24
2025-09-24
Participant Flow
Participant milestones
| Measure |
Daily Oral Vitamin D3
Oral vitamin D3, 3,333 IU
Daily oral vitamin D3, 3,333 IU: Oral vitamin D3, 3,333 IU, will be administered daily.
|
Monthly Bolus Oral Vitamin D3
Bolus oral vitamin D3, 100,000 IU
Bolus oral vitamin D3, 100,000 IU: Bolus oral vitamin D3, 100,000 IU, will be administered monthly.
Placebo oral tablet: Participants randomized to receive once monthly oral bolus of vitamin D3, will receive placebo on all other days of the month.
|
|---|---|---|
|
Overall Study
STARTED
|
27
|
31
|
|
Overall Study
COMPLETED
|
22
|
23
|
|
Overall Study
NOT COMPLETED
|
5
|
8
|
Reasons for withdrawal
| Measure |
Daily Oral Vitamin D3
Oral vitamin D3, 3,333 IU
Daily oral vitamin D3, 3,333 IU: Oral vitamin D3, 3,333 IU, will be administered daily.
|
Monthly Bolus Oral Vitamin D3
Bolus oral vitamin D3, 100,000 IU
Bolus oral vitamin D3, 100,000 IU: Bolus oral vitamin D3, 100,000 IU, will be administered monthly.
Placebo oral tablet: Participants randomized to receive once monthly oral bolus of vitamin D3, will receive placebo on all other days of the month.
|
|---|---|---|
|
Overall Study
Lost to Follow-up
|
2
|
2
|
|
Overall Study
Withdrawal by Subject
|
1
|
5
|
|
Overall Study
Non-adherence
|
1
|
1
|
|
Overall Study
Adverse Event
|
1
|
0
|
Baseline Characteristics
Daily Vitamin D for Sickle-cell Respiratory Complications
Baseline characteristics by cohort
| Measure |
Daily Oral Vitamin D3
n=27 Participants
Oral vitamin D3, 3,333 IU
Daily oral vitamin D3, 3,333 IU: Oral vitamin D3, 3,333 IU, will be administered daily.
|
Monthly Bolus Oral Vitamin D3
n=31 Participants
Bolus oral vitamin D3, 100,000 IU
Bolus oral vitamin D3, 100,000 IU: Bolus oral vitamin D3, 100,000 IU, will be administered monthly.
Placebo oral tablet: Participants randomized to receive once monthly oral bolus of vitamin D3, will receive placebo on all other days of the month.
|
Total
n=58 Participants
Total of all reporting groups
|
|---|---|---|---|
|
Age, Categorical
<=18 years
|
25 Participants
n=5 Participants
|
30 Participants
n=7 Participants
|
55 Participants
n=5 Participants
|
|
Age, Categorical
Between 18 and 65 years
|
2 Participants
n=5 Participants
|
1 Participants
n=7 Participants
|
3 Participants
n=5 Participants
|
|
Age, Categorical
>=65 years
|
0 Participants
n=5 Participants
|
0 Participants
n=7 Participants
|
0 Participants
n=5 Participants
|
|
Sex: Female, Male
Female
|
12 Participants
n=5 Participants
|
16 Participants
n=7 Participants
|
28 Participants
n=5 Participants
|
|
Sex: Female, Male
Male
|
15 Participants
n=5 Participants
|
15 Participants
n=7 Participants
|
30 Participants
n=5 Participants
|
|
Ethnicity (NIH/OMB)
Hispanic or Latino
|
17 Participants
n=5 Participants
|
17 Participants
n=7 Participants
|
34 Participants
n=5 Participants
|
|
Ethnicity (NIH/OMB)
Not Hispanic or Latino
|
9 Participants
n=5 Participants
|
12 Participants
n=7 Participants
|
21 Participants
n=5 Participants
|
|
Ethnicity (NIH/OMB)
Unknown or Not Reported
|
1 Participants
n=5 Participants
|
2 Participants
n=7 Participants
|
3 Participants
n=5 Participants
|
|
Race (NIH/OMB)
American Indian or Alaska Native
|
0 Participants
n=5 Participants
|
0 Participants
n=7 Participants
|
0 Participants
n=5 Participants
|
|
Race (NIH/OMB)
Asian
|
0 Participants
n=5 Participants
|
0 Participants
n=7 Participants
|
0 Participants
n=5 Participants
|
|
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
|
0 Participants
n=5 Participants
|
0 Participants
n=7 Participants
|
0 Participants
n=5 Participants
|
|
Race (NIH/OMB)
Black or African American
|
11 Participants
n=5 Participants
|
17 Participants
n=7 Participants
|
28 Participants
n=5 Participants
|
|
Race (NIH/OMB)
White
|
4 Participants
n=5 Participants
|
6 Participants
n=7 Participants
|
10 Participants
n=5 Participants
|
|
Race (NIH/OMB)
More than one race
|
8 Participants
n=5 Participants
|
4 Participants
n=7 Participants
|
12 Participants
n=5 Participants
|
|
Race (NIH/OMB)
Unknown or Not Reported
|
4 Participants
n=5 Participants
|
4 Participants
n=7 Participants
|
8 Participants
n=5 Participants
|
|
Region of Enrollment
United States
|
27 participants
n=5 Participants
|
31 participants
n=7 Participants
|
58 participants
n=5 Participants
|
PRIMARY outcome
Timeframe: Month 12, Month 24Respiratory events will be calculated as the sum of respiratory infection, asthma exacerbation, and acute chest syndrome, as ascertained by use of a validated questionnaire.
Outcome measures
| Measure |
Daily Oral Vitamin D3
n=27 Participants
Oral vitamin D3, 3,333 IU
Daily oral vitamin D3, 3,333 IU: Oral vitamin D3, 3,333 IU, will be administered daily.
|
Monthly Bolus Oral Vitamin D3
n=31 Participants
Bolus oral vitamin D3, 100,000 IU
Bolus oral vitamin D3, 100,000 IU: Bolus oral vitamin D3, 100,000 IU, will be administered monthly.
Placebo oral tablet: Participants randomized to receive once monthly oral bolus of vitamin D3, will receive placebo on all other days of the month.
|
|---|---|---|
|
Annual Rate of Respiratory Events
Treatment Year 1
|
3.3 Respiratory events per year
Standard Deviation 2.1
|
3.3 Respiratory events per year
Standard Deviation 2.6
|
|
Annual Rate of Respiratory Events
Treatment Year 2
|
3.4 Respiratory events per year
Standard Deviation 1.7
|
3.2 Respiratory events per year
Standard Deviation 2.4
|
SECONDARY outcome
Timeframe: Baseline, Month 24Population: Due to COVID-19 restrictions, data was only collected/analyzed for 13 out of 27 at baseline and 18 out of 27 at month 24 for DAILY ARM; data was collected/analyzed for 14 out of 31 at baseline and 21 out 31 at month 24 for MONTHLY ARM.
This is to measure the forced vital capacity (FVC; % predicted) at baseline and at month 24. Forced Vital Capacity (FVC) is a key measure of lung function that indicates the total volume of air a person can forcefully exhale after taking a deep breath. It is calculated using spirometry, which assesses lung capacity and helps diagnose respiratory conditions. Predicted FVC: The FVC is compared to predicted values based on age, height, and sex to determine if it is within the normal range (80% or more of predicted). Interpretation: A low FVC may indicate obstruction (e.g., asthma or COPD), while a high FVC may suggest restriction in lung function. Baseline Measurement: It is essential to establish a baseline FVC to monitor changes over time and assess the effectiveness of treatments. For accurate interpretation, it is crucial to compare FVC results with other measurements, such as FEV1, to identify the presence of obstructive or restrictive lung disease.
Outcome measures
| Measure |
Daily Oral Vitamin D3
n=18 Participants
Oral vitamin D3, 3,333 IU
Daily oral vitamin D3, 3,333 IU: Oral vitamin D3, 3,333 IU, will be administered daily.
|
Monthly Bolus Oral Vitamin D3
n=21 Participants
Bolus oral vitamin D3, 100,000 IU
Bolus oral vitamin D3, 100,000 IU: Bolus oral vitamin D3, 100,000 IU, will be administered monthly.
Placebo oral tablet: Participants randomized to receive once monthly oral bolus of vitamin D3, will receive placebo on all other days of the month.
|
|---|---|---|
|
Mean Forced Vital Capacity (FVC % Predicted)
Baseline
|
86.3 percent predicted
Standard Deviation 9.4
|
84.3 percent predicted
Standard Deviation 13.2
|
|
Mean Forced Vital Capacity (FVC % Predicted)
Month 24
|
83.2 percent predicted
Standard Deviation 9.9
|
88.7 percent predicted
Standard Deviation 11.8
|
SECONDARY outcome
Timeframe: Baseline, Month 24Population: Due to COVID-19 restrictions, data was only collected/analyzed for 13 out of 27 at baseline and 18 out of 27 at month 24 for DAILY ARM; data was collected/analyzed for 14 out of 31 at baseline and 21 out 31 at month 24 for MONTHLY ARM.
Forced Expiratory Volume in 1 second (FEV1; % predicted) at baseline and at month 24.
Outcome measures
| Measure |
Daily Oral Vitamin D3
n=18 Participants
Oral vitamin D3, 3,333 IU
Daily oral vitamin D3, 3,333 IU: Oral vitamin D3, 3,333 IU, will be administered daily.
|
Monthly Bolus Oral Vitamin D3
n=21 Participants
Bolus oral vitamin D3, 100,000 IU
Bolus oral vitamin D3, 100,000 IU: Bolus oral vitamin D3, 100,000 IU, will be administered monthly.
Placebo oral tablet: Participants randomized to receive once monthly oral bolus of vitamin D3, will receive placebo on all other days of the month.
|
|---|---|---|
|
Forced Expiratory Volume in 1 Second (FEV1)
Baseline
|
84.6 percent predicted
Standard Deviation 9.2
|
84.4 percent predicted
Standard Deviation 12.5
|
|
Forced Expiratory Volume in 1 Second (FEV1)
Month 24
|
85.5 percent predicted
Standard Deviation 12.6
|
90.8 percent predicted
Standard Deviation 12.9
|
SECONDARY outcome
Timeframe: Baseline, Month 24Population: Due to COVID-19 restrictions, data was only collected/analyzed for 13 out of 27 at baseline and 18 out of 27 at month 24 for DAILY ARM; data was collected/analyzed for 14 out of 31 at baseline and 21 out 31 at month 24 for MONTHLY ARM.
Forced Expiratory Volume in 1 second (FEV1; % predicted)/Forced Vital Capacity (FVC) \[FEV1/FVC\] % predicted at baseline and month 24
Outcome measures
| Measure |
Daily Oral Vitamin D3
n=18 Participants
Oral vitamin D3, 3,333 IU
Daily oral vitamin D3, 3,333 IU: Oral vitamin D3, 3,333 IU, will be administered daily.
|
Monthly Bolus Oral Vitamin D3
n=21 Participants
Bolus oral vitamin D3, 100,000 IU
Bolus oral vitamin D3, 100,000 IU: Bolus oral vitamin D3, 100,000 IU, will be administered monthly.
Placebo oral tablet: Participants randomized to receive once monthly oral bolus of vitamin D3, will receive placebo on all other days of the month.
|
|---|---|---|
|
Forced Expiratory Volume in 1 Second (FEV1)/Forced Vital Capacity Ratio
Baseline
|
97.9 ratio
Standard Deviation 6.5
|
100.1 ratio
Standard Deviation 8.0
|
|
Forced Expiratory Volume in 1 Second (FEV1)/Forced Vital Capacity Ratio
Month 24
|
97.5 ratio
Standard Deviation 8.0
|
97.7 ratio
Standard Deviation 9.8
|
SECONDARY outcome
Timeframe: Baseline, Month 24Population: Due to COVID-19 restrictions, data was only collected/analyzed for 13 out of 27 at baseline and 18 out of 27 at month 24 for DAILY ARM; data was collected/analyzed for 14 out of 31 at baseline and 21 out 31 at month 24 for MONTHLY ARM.
Forced Expiratory Flow at 25%-75% vital capacity (FEF25-75) % predicted at baseline and month 24 .
Outcome measures
| Measure |
Daily Oral Vitamin D3
n=18 Participants
Oral vitamin D3, 3,333 IU
Daily oral vitamin D3, 3,333 IU: Oral vitamin D3, 3,333 IU, will be administered daily.
|
Monthly Bolus Oral Vitamin D3
n=21 Participants
Bolus oral vitamin D3, 100,000 IU
Bolus oral vitamin D3, 100,000 IU: Bolus oral vitamin D3, 100,000 IU, will be administered monthly.
Placebo oral tablet: Participants randomized to receive once monthly oral bolus of vitamin D3, will receive placebo on all other days of the month.
|
|---|---|---|
|
Forced Expiratory Flow at 25%-75% Vital Capacity (FEF25-75, % Predicted)
Baseline
|
80.9 percent predicted
Standard Deviation 22.3
|
86.6 percent predicted
Standard Deviation 24.8
|
|
Forced Expiratory Flow at 25%-75% Vital Capacity (FEF25-75, % Predicted)
Month 24
|
81.1 percent predicted
Standard Deviation 26.5
|
83.7 percent predicted
Standard Deviation 25.0
|
SECONDARY outcome
Timeframe: Baseline, Month 24Population: Due to COVID-19 restrictions, data was only collected/analyzed for 11 out of 27 at baseline and 16 out of 27 at month 24 for DAILY ARM; data was collected/analyzed for 12 out of 31 at baseline and 18 out 31 at month 24 for MONTHLY ARM.
Ratio of Residual Lung Volume (RV) to Total Lung Capacity (RV/TLC) at baseline and month 24.
Outcome measures
| Measure |
Daily Oral Vitamin D3
n=16 Participants
Oral vitamin D3, 3,333 IU
Daily oral vitamin D3, 3,333 IU: Oral vitamin D3, 3,333 IU, will be administered daily.
|
Monthly Bolus Oral Vitamin D3
n=18 Participants
Bolus oral vitamin D3, 100,000 IU
Bolus oral vitamin D3, 100,000 IU: Bolus oral vitamin D3, 100,000 IU, will be administered monthly.
Placebo oral tablet: Participants randomized to receive once monthly oral bolus of vitamin D3, will receive placebo on all other days of the month.
|
|---|---|---|
|
Ratio of Residual Lung Volume (RV) to Total Lung Capacity (TLC)
Baseline
|
121.0 ratio
Standard Deviation 28.2
|
101.2 ratio
Standard Deviation 28.9
|
|
Ratio of Residual Lung Volume (RV) to Total Lung Capacity (TLC)
Month 24
|
106.9 ratio
Standard Deviation 34.6
|
109.1 ratio
Standard Deviation 19.0
|
SECONDARY outcome
Timeframe: Baseline, Month 24Population: Due to COVID-19 restrictions, data was only collected/analyzed for 11 out of 27 at baseline and 16 out of 27 at month 24 for DAILY ARM; data was collected/analyzed for 12 out of 31 at baseline and 18 out 31 at month 24 for MONTHLY ARM.
Diffusing Capacity of the Lungs for Carbon Monoxide (DLCO; % predicted) at baseline and month 24
Outcome measures
| Measure |
Daily Oral Vitamin D3
n=16 Participants
Oral vitamin D3, 3,333 IU
Daily oral vitamin D3, 3,333 IU: Oral vitamin D3, 3,333 IU, will be administered daily.
|
Monthly Bolus Oral Vitamin D3
n=18 Participants
Bolus oral vitamin D3, 100,000 IU
Bolus oral vitamin D3, 100,000 IU: Bolus oral vitamin D3, 100,000 IU, will be administered monthly.
Placebo oral tablet: Participants randomized to receive once monthly oral bolus of vitamin D3, will receive placebo on all other days of the month.
|
|---|---|---|
|
Diffusing Capacity of the Lungs for Carbon Monoxide (DLCO)
Baseline
|
87.3 percent predicted
Standard Deviation 10.3
|
85.3 percent predicted
Standard Deviation 15.8
|
|
Diffusing Capacity of the Lungs for Carbon Monoxide (DLCO)
Month 24
|
86.5 percent predicted
Standard Deviation 12.5
|
90.0 percent predicted
Standard Deviation 14.1
|
SECONDARY outcome
Timeframe: Baseline, Month 12, Month 24Population: Data was collected and analyzed only for the following numbers of study participants out of 27 for DAILY ARM and 31 for MONTHLY ARM at each time point due to some study participants did not complete the study.
Blood Neutrophil Count in percentage at baseline, month 12 and month 24
Outcome measures
| Measure |
Daily Oral Vitamin D3
n=27 Participants
Oral vitamin D3, 3,333 IU
Daily oral vitamin D3, 3,333 IU: Oral vitamin D3, 3,333 IU, will be administered daily.
|
Monthly Bolus Oral Vitamin D3
n=31 Participants
Bolus oral vitamin D3, 100,000 IU
Bolus oral vitamin D3, 100,000 IU: Bolus oral vitamin D3, 100,000 IU, will be administered monthly.
Placebo oral tablet: Participants randomized to receive once monthly oral bolus of vitamin D3, will receive placebo on all other days of the month.
|
|---|---|---|
|
Neutrophil Count
Baseline
|
45.8 Percentage of Neutrophils
Standard Deviation 13.5
|
43.9 Percentage of Neutrophils
Standard Deviation 9.6
|
|
Neutrophil Count
Month 12
|
47.7 Percentage of Neutrophils
Standard Deviation 13.8
|
43.0 Percentage of Neutrophils
Standard Deviation 11.0
|
|
Neutrophil Count
Month 24
|
45.5 Percentage of Neutrophils
Standard Deviation 14.8
|
46.8 Percentage of Neutrophils
Standard Deviation 12.0
|
SECONDARY outcome
Timeframe: Baseline, Month 12, Month 24Population: Data was collected and analyzed only for the following numbers of study participants out of 27 for DAILY ARM and 31 for MONTHLY ARM at each time point due to some study participants did not complete the study.
Blood Platelet Count (Platelets\*10\^3/ per μL) at baseline, month 12 and month 24
Outcome measures
| Measure |
Daily Oral Vitamin D3
n=27 Participants
Oral vitamin D3, 3,333 IU
Daily oral vitamin D3, 3,333 IU: Oral vitamin D3, 3,333 IU, will be administered daily.
|
Monthly Bolus Oral Vitamin D3
n=31 Participants
Bolus oral vitamin D3, 100,000 IU
Bolus oral vitamin D3, 100,000 IU: Bolus oral vitamin D3, 100,000 IU, will be administered monthly.
Placebo oral tablet: Participants randomized to receive once monthly oral bolus of vitamin D3, will receive placebo on all other days of the month.
|
|---|---|---|
|
Platelet Count
Baseline
|
355.1 Platelets *10^3/ per μL
Standard Deviation 191.1
|
376.2 Platelets *10^3/ per μL
Standard Deviation 242.0
|
|
Platelet Count
Month 12
|
390.0 Platelets *10^3/ per μL
Standard Deviation 125.0
|
387.2 Platelets *10^3/ per μL
Standard Deviation 191.8
|
|
Platelet Count
Month 24
|
398.9 Platelets *10^3/ per μL
Standard Deviation 157.3
|
359.9 Platelets *10^3/ per μL
Standard Deviation 150.1
|
SECONDARY outcome
Timeframe: Baseline, Month 12, Month 24Population: Data was collected and analyzed only for the following numbers of study participants out of 27 for DAILY ARM and 31 for MONTHLY ARM at each time point due to some study participants did not complete the study.
Serum C-reactive protein (CRP; mg/L) at baseline, month 12 and month 24
Outcome measures
| Measure |
Daily Oral Vitamin D3
n=27 Participants
Oral vitamin D3, 3,333 IU
Daily oral vitamin D3, 3,333 IU: Oral vitamin D3, 3,333 IU, will be administered daily.
|
Monthly Bolus Oral Vitamin D3
n=31 Participants
Bolus oral vitamin D3, 100,000 IU
Bolus oral vitamin D3, 100,000 IU: Bolus oral vitamin D3, 100,000 IU, will be administered monthly.
Placebo oral tablet: Participants randomized to receive once monthly oral bolus of vitamin D3, will receive placebo on all other days of the month.
|
|---|---|---|
|
Serum C-reactive Protein (CRP)
Baseline
|
2.1 mg/L
Standard Deviation 2.6
|
2.9 mg/L
Standard Deviation 3.7
|
|
Serum C-reactive Protein (CRP)
Month 12
|
5.9 mg/L
Standard Deviation 13.7
|
3.6 mg/L
Standard Deviation 5.0
|
|
Serum C-reactive Protein (CRP)
Month 24
|
3.0 mg/L
Standard Deviation 2.9
|
4.6 mg/L
Standard Deviation 7.9
|
Adverse Events
Daily Oral Vitamin D3
Monthly Bolus Oral Vitamin D3
Serious adverse events
| Measure |
Daily Oral Vitamin D3
n=27 participants at risk
Oral vitamin D3, 3,333 IU
Daily oral vitamin D3, 3,333 IU: Oral vitamin D3, 3,333 IU, will be administered daily.
|
Monthly Bolus Oral Vitamin D3
n=31 participants at risk
Bolus oral vitamin D3, 100,000 IU
Bolus oral vitamin D3, 100,000 IU: Bolus oral vitamin D3, 100,000 IU, will be administered monthly.
Placebo oral tablet: Participants randomized to receive once monthly oral bolus of vitamin D3, will receive placebo on all other days of the month.
|
|---|---|---|
|
General disorders
Pain syndrome
|
29.6%
8/27 • Number of events 9 • Up to 2 years
|
9.7%
3/31 • Number of events 3 • Up to 2 years
|
|
Surgical and medical procedures
Splenic sequestration
|
3.7%
1/27 • Number of events 1 • Up to 2 years
|
0.00%
0/31 • Up to 2 years
|
|
General disorders
Acute chest syndrome
|
18.5%
5/27 • Number of events 6 • Up to 2 years
|
0.00%
0/31 • Up to 2 years
|
|
Infections and infestations
Bone infection
|
3.7%
1/27 • Number of events 1 • Up to 2 years
|
0.00%
0/31 • Up to 2 years
|
|
Infections and infestations
Clinical sepsis
|
3.7%
1/27 • Number of events 1 • Up to 2 years
|
0.00%
0/31 • Up to 2 years
|
|
Infections and infestations
COVID-19
|
3.7%
1/27 • Number of events 1 • Up to 2 years
|
0.00%
0/31 • Up to 2 years
|
Other adverse events
| Measure |
Daily Oral Vitamin D3
n=27 participants at risk
Oral vitamin D3, 3,333 IU
Daily oral vitamin D3, 3,333 IU: Oral vitamin D3, 3,333 IU, will be administered daily.
|
Monthly Bolus Oral Vitamin D3
n=31 participants at risk
Bolus oral vitamin D3, 100,000 IU
Bolus oral vitamin D3, 100,000 IU: Bolus oral vitamin D3, 100,000 IU, will be administered monthly.
Placebo oral tablet: Participants randomized to receive once monthly oral bolus of vitamin D3, will receive placebo on all other days of the month.
|
|---|---|---|
|
General disorders
Pain syndrome
|
74.1%
20/27 • Number of events 50 • Up to 2 years
|
51.6%
16/31 • Number of events 30 • Up to 2 years
|
|
Infections and infestations
Upper respiratory infection
|
33.3%
9/27 • Number of events 17 • Up to 2 years
|
38.7%
12/31 • Number of events 17 • Up to 2 years
|
Additional Information
Results disclosure agreements
- Principal investigator is a sponsor employee
- Publication restrictions are in place