The objective of the study is to evaluate the clinical efficacy and safety of vitamin D supplementation in hospitalized patients with COVID-19.

Phase IV, interventional, randomised, double blind, placebo-controlled and parallel study to evaluate the clinical efficacy and safety of vitamin D supplementation in hospitalized patients with COVID-19.

Patients will participate in the study for a maximum of 9 weeks, which includes an up to 6-week treatment period and a maximum of 3-week follow-up period.

A total of 100 (50 in each group) patients will be randomized in the study and will either receive the test treatment or the placebo treatment.

Inclusion Criteria:

• Male and female over 18 years old (18 years inclusive).
• Has laboratory-confirmed SARS-CoV-2 infection as determined by PCR, or other commercial or public health assay in any specimen as diagnosed within 72 hours prior to randomization.
• Expected to survive for at least 96 hours after study entry.
• If patient is a female of childbearing potential, patient must use an effective means of birth control (oral, intravaginal or transdermal oestrogen-progestogen combined hormonal contraceptives or intrauterine devices or sexual abstinence).
• Subject or legally authorized representative understands and agrees to comply with planned study procedures.
• Subject or legally authorized representative provides informed consent prior to initiation of any study procedures.

Exclusion Criteria:

• Women currently pregnant or breast-feeding.
• Patients presenting acute impairment of renal function or nephrolithiasis.
• Patients presenting hypercalcaemia and/or hypercalciuria
• Patients presenting pseudohypoparathyroidism
• Use of any vitamin D supplementation alone or in association at screening visit;
• Use of any prohibited medication as detailed in the concomitant medication section
• Patients with any sensitivity or allergy to any of the products used within this clinical trial.
• Presence of any other condition or illness, which, in the opinion of the investigator, would interfere with optimal participation in the study.