{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,6]],"date-time":"2026-04-06T18:35:20Z","timestamp":1775500520159,"version":"3.50.1"},"reference-count":20,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2024,1,19]],"date-time":"2024-01-19T00:00:00Z","timestamp":1705622400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"FAES FARMA, S.A."}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nutrients"],"abstract":"<jats:p>Vitamin D deficiency is highly prevalent, and recent evidence suggests a possible association between vitamin D deficiency and various health conditions. The aim of this study was to assess monthly calcifediol treatments for vitamin D deficiency (or biweekly, if the deficiency was severe) in a young adult population with no associated comorbidities. This multicentre phase I trial started with a four month open-label treatment phase (TP) that included 101 participants (65% women with mean age 29.8 years). Eighty-two percent of the subjects (79\/96) achieved 25(OH)D levels within the target range (20\u201360 ng\/mL) by the end of the TP, and they were subsequently randomised and subjected to a double-blind, placebo-controlled, five month follow-up phase (FP). At the end of the FP, 89% of participants maintained vitamin D levels of &gt;20 ng\/mL with calcifediol, versus 49% with placebo (p &lt; 0.001). Subjects receiving monthly calcifediol during both phases (n = 32) maintained 25(OH)D levels &gt;20 ng\/mL, whereas those on the placebo during the FP (n = 38) exhibited deficiency levels of 25(OH)D by the end of the study. No clinically relevant changes in bone metabolism parameters or toxic 25(OH)D levels were observed, and no serious adverse events were reported throughout the study. Calcifediol is a safe and effective treatment for vitamin D deficiency in the young adult population, but long-term use may be required to sustain optimal 25(OH)D levels.<\/jats:p>","DOI":"10.3390\/nu16020306","type":"journal-article","created":{"date-parts":[[2024,1,19]],"date-time":"2024-01-19T05:46:44Z","timestamp":1705643204000},"page":"306","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Efficacy and Safety of Calcifediol in Young Adults with Vitamin D Deficiency: A Phase I, Multicentre, Clinical Trial\u2014POSCAL Study"],"prefix":"10.3390","volume":"16","author":[{"given":"Pedro","family":"Guerra L\u00f3pez","sequence":"first","affiliation":[{"name":"Clinical Trials Unit, Pharmacology Department, Universidad Aut\u00f3noma de Madrid, 28049 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6951-5518","authenticated-orcid":false,"given":"Mikel","family":"Urroz Elizalde","sequence":"additional","affiliation":[{"name":"Clinical Trials Unit, Pharmacology Department, Universidad Aut\u00f3noma de Madrid, 28049 Madrid, Spain"},{"name":"Clinical Pharmacology Service, Hospital Universitario La Paz, 28049 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Noelia","family":"Vega-Gil","sequence":"additional","affiliation":[{"name":"Valdecilla Clinical Trials Unit, Hospital Universitario Marqu\u00e9s de Valdecilla-IDIVAL, 39008 Santander, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0005-8077-3752","authenticated-orcid":false,"given":"Blanca","family":"S\u00e1nchez Santiago","sequence":"additional","affiliation":[{"name":"Valdecilla Clinical Trials Unit, Hospital Universitario Marqu\u00e9s de Valdecilla-IDIVAL, 39008 Santander, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"I\u00f1aki","family":"Zorrilla Mart\u00ednez","sequence":"additional","affiliation":[{"name":"Clinical Trials Unit, IIS BIOARABA, 01009 Vitoria-Gasteiz, Spain"},{"name":"Mental Health and Childhood Research Group, IIS BIOARABA, 01009 Vitoria-Gasteiz, Spain"},{"name":"Psychiatry Department, Araba University Hospital, 01009 Vitoria-Gasteiz, Spain"},{"name":"Department of Neurosciences, University of the Basque Country UPV\/EHU, 01006 Vitoria-Gasteiz, Spain"},{"name":"CIBER of Mental Health (CIBERSAM), Institute of Health Carlos III, 28029 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8248-2821","authenticated-orcid":false,"given":"Mario","family":"Jim\u00e9nez-Mercado","sequence":"additional","affiliation":[{"name":"Clinical Trials Unit, IIS BIOARABA, 01009 Vitoria-Gasteiz, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Esteban","family":"J\u00f3dar","sequence":"additional","affiliation":[{"name":"Department of Endocrinology and Nutrition, Quir\u00f3nsalud Madrid University Hospital, 28233 Madrid, Spain"},{"name":"School of Health Sciences, European University of Madrid, 28670 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Araitz","family":"Landeta Manzano","sequence":"additional","affiliation":[{"name":"Medical Affairs, FAES FARMA S.A., 48940 Leioa, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Cristina","family":"Campo Hoyos","sequence":"additional","affiliation":[{"name":"Medical Affairs, FAES FARMA S.A., 48940 Leioa, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jes\u00fas","family":"Fr\u00edas Iniesta","sequence":"additional","affiliation":[{"name":"Clinical Trials Unit, Pharmacology Department, Universidad Aut\u00f3noma de Madrid, 28049 Madrid, Spain"},{"name":"Clinical Pharmacology Service, Hospital Universitario La Paz, 28049 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2024,1,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"266","DOI":"10.1056\/NEJMra070553","article-title":"Vitamin D Deficiency","volume":"357","author":"Holick","year":"2007","journal-title":"N. 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