Children aged 6 months to 12 years of age will be randomised to receive vitamin D 60,000IU once a month for 3 months or a placebo. The vitamin D will be in form of granules supplied in sachets. The primary study outcomes will be incidence of hospitalisation and change in vitamin D levels following supplementation. Secondary outcomes will include incidence of vaso-occlusive crisis (VOC), acute severe respiratory illness, Vitamin D related Severe adverse events and requirements for blood transfusion

BACKGROUND: More than 75% of all children with sickle cell anemia (SCA) are born in sub-Saharan Africa annually. The hallmark of SCA is haemolytic anaemia and or pain crisis that often require hospitalisation. Interventions to reduce the complications, which are prerequisites for frequent hospitalisations, are needed urgently. Vitamin D deficiency is common in children with SCA and is associated with recurrent vaso-occlusive crisis, blood transfusion, hospitalisation and infections. Routine vitamin D supplementation is not practiced in the care of sickle cell disease patients yet it has been associated with improved bone health and bone mineral density, reduced chronic pain and improved quality of life.

HYPOTHESIS: Vitamin D supplementation will lead to a lower incidence of hospitalisation than placebo in Ugandan children with SCA.

METHODS: The study will be a randomized, placebo-controlled, double blind clinical trial in which 331 Ugandan children with SCA aged 6 months to 12 years inclusive will receive vitamin D (60,000IU granules monthly) and another 331 a placebo (identical to vitaminD in appearance) for 3 months. The primary study outcome will be incidence of hospitalisation. Secondary outcomes will include incidence of vaso-occlusive crisis (VOC), acute severe respiratory illness, Vitamin D related Severe adverse events and requirements for blood transfusion IMPACT: If this trial shows a reduction in hospitalisation, it will be the basis for a multi-site pre-post intervention clinical trial to assess real-world safety and efficacy of Vitamin D in African children with SCA. The monthly administration is easy, and since vitamin D is inexpensive, this trial has the potential to improve the health of hundreds/ thousands of African children with SCA through reduction of infection-related morbidity and mortality.

Inclusion Criteria:

1. Documented sickle cell disease (HbSS supported by hemoglobin electrophoresis results) attending Mulago Hospital Sickle Cell Clinic)
2. Age range of 6 months to 12 years, inclusive, at the time of enrolment
3. Weight at least 5.0 kg at the time of enrolment
4. Willingness to comply with all study-related treatments, evaluations, and follow-up

Exclusion Criteria:

1. Known other chronic medical condition (e.g., HIV, malignancy, Renal & liver disease, active clinical tuberculosis)
2. Severe acute malnutrition determined by impaired growth parameters as defined by WHO weight for length/height less than -3SD.
3. Evidence of Vitamin D supplementation in the past one month (by prescription or drug sample)

De-identified participant information may be shared with other researchers.

within one year and the sharing period could extend beyond this period

If requested by other researchers who have carried out similar studies for a meta-analysis

The sachets containing vitamin D will be exactly similar to the ones containing the placebo. Both the intervention and placebo granules will be identical in colour, odour, taste and amount. Children will be randomized into treatment groups by order of entry in the study, based on a pre-determined blinded randomization list created and managed by an independent statistician.