This study evaluates vitamin D as an adjunctive treatment in patients with non-Cystic Fibrosis bronchiectasis, which are combined with vitamin D deficiency. Half of participants will receive vitamin D supplementation, while the other half will receive placebo.

To define the therapeutic effect of Vitamin D in the treatment of non-Cystic Fibrosis bronchiectasis by means of a prospective randomized placebo-controlled double blind study with a follow-up of at least one year. To explore whether correction of Vitamin D deficiency by the oral supplementation of Vitamin D triggers the vitamin D receptors-mediated cathelicidin pathway and increases local or systemic concentrations of the natural antimicrobial polypeptide cathelicidin with enhanced eradication of bacteria.

Inclusion Criteria:

• Diagnosis of non-Cystic fibrosis bronchiectasis by High Resolution CT
• Age 18 years or older
• Vitamin D deficiency [25(OH)D<20 ng/mL]
• Informed consent

Exclusion Criteria:

• Current active allergic bronchopulmonary or tuberculosis
• Diagnosis of any of the following: sarcoidosis, hyperparathyroidism, nephrolithiasis, pulmonary silicosis, Human Immunodeficiency Virus infection, liver failure, renal failure or malignancy
• Taking benzothiadiazine derivative, cardiac glycoside, carbamazepine, phenobarbital, phenytoin or primidone
• Taking dietary supplement or topical preparation containing vitamin D up to 2 months before first dose
• Treatment with any investigational medical product or device up to 4 months before first dose
• Breastfeeding, pregnant or planning a pregnancy
• Baseline corrected serum calcium > 2.65 mmol/L
• Baseline serum creatinine > 125 micromol/L