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Vitamin D Deficiency clinical trials

The registry lists 801 studies for Vitamin D Deficiency across more than 10 countries. 60 are recruiting or about to start. 493 of them are mainly about Vitamin D Deficiency (how this is decided). Per ClinicalTrials.gov, last updated 2026-11-04. Counting its 5 narrower conditions too, such as Chronic Kidney Disease-Mineral and Bone Disorder: 961 studies, 91 open.

ClinicalTrials.gov finds 1,090 studies for Vitamin D Deficiency. How that becomes 801 here

This page counts the studies the registry files under Vitamin D Deficiency, and those it files under no condition that list Vitamin D Deficiencythemselves. Each study its search finds is placed by how the registry filed it and by the conditions it lists. ClinicalTrials.gov counts as of Nov 8, 2026. How condition pages count

  1. 1,090Found by its condition searchIt reads the conditions a study lists and their synonyms, and also titles and keywords.
  2. −159Filed under a narrower condition, counted on its own pageChronic Kidney Disease-Mineral and Bone Disorder 69 · Familial Hypophosphatemic Rickets 49 · Osteomalacia 29 · Rickets 9 · Rickets, Hypophosphatemic 3
  3. −130Match it another way49 name it in the title and 81 by a synonym or other text the search reads.
  4. 801The count on this page4 of them list Vitamin D Deficiency in their own words; the registry filed them under no condition.

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Status

Completed
557
Status unknown
94
Terminated
38
Recruiting
37
Active, not recruiting
25
Withdrawn
24

Phase

Phase 4
95
Phase 2
78
Phase 3
74
Phase 1
35
Early Phase 1
17

Where

United States
251
Turkey
44
Egypt
39
United Kingdom
29
China
28
Israel
18

Who runs them

University of Wisconsin, Madison (14) · Ain Shams University (10) · Massachusetts General Hospital (10) · Creighton University (10) · Cairo University (10) · Medical University of Graz (9) · University of Aarhus (8) · Second Affiliated Hospital of Wenzhou Medical University (8)

What is being tested here

Drugs under test in Vitamin D Deficiency studies, those with the most open studies first. Medicines only given beside them are not counted. How drugs are counted

DrugOpenPhase 3All
Vitamin D158154
Cholecalciferol938228
Ergocalciferols1138
Calcifediol1512
Calcium1012
Calcitriol117
Sucrosomial iron101
Vitamin A101
Modified-release Calcifediol Capsule044
Calcium Carbonate014

Coming up

3phase 3 studies under way
19studies finish main data collection within a year2 of them phase 3

Studies recruiting or running, from their records. “Main data collection” ends at the primary completion date, the sponsor’s own estimate, which often moves.

The 10 nearest, phase 3 first

Who these studies take

Of the 37 Vitamin D Deficiency studies recruiting now, 16 (43%) set no upper age limit and 18 (49%) stop at 75 or younger. 10 (27%) take children under 18. 3 (8%) are for women only and 5 (14%) for men only; 11 (30%) take healthy volunteers.

Recruiting studies that take each age, of 37
AgeWomenMen
108 (22%)8 (22%)
1823 (62%)21 (57%)
3023 (62%)24 (65%)
4023 (62%)25 (68%)
5023 (62%)22 (59%)
6521 (57%)21 (57%)
7518 (49%)17 (46%)
8515 (41%)15 (41%)

Across all 801 studies, recruiting or not: 57% stop at 75 or younger and 46% at 65; 23% take children; 17% are for women only and 4% for men only; 48% take healthy volunteers. From each study’s registry entry; the criteria on its page decide.

How long Vitamin D Deficiency studies take

Of 37 phase 4 interventional studies under Vitamin D Deficiency, half reached primary completion within 18 months of starting, counting those still running.

Start to primary completionEvery sponsorIndustryNon-industry
Phase 123 mo9–44 · 13 studies——
Phase 232 mo18–45 · 18 studies——
Phase 332 mo10–43 · 18 studies——
Phase 418 mo8–29 · 37 studies—17 mo8–31 · 36 studies
Interventional, no phase11 mo4–29 · 170 studies—11 mo4–29 · 168 studies
Observational19 mo9–40 · 62 studies—19 mo9–40 · 61 studies

Each figure is the month by which half the studies had reached primary completion, with the range in which the middle half did. Studies still running count until their last registry update; studies that stopped early are left out. Phase 1 includes early phase 1; observational means prospective or not stated, as retrospective and cross-sectional studies date a window of data rather than a study. How these figures are worked out

What changed recently

From the registry's own updates since Oct 13, 2026.

Newly registered2

Studies

Recruiting first, then most recently updated. Showing 50 of 801. Browse all 801 → or search them.