An interventional study of Yellow cassava and White cassava in Vitamin A Deficiency, sponsored by Wageningen University. Completed at 1 site in Kenya. Open to participants aged 61 Months to 13 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2022-11-21.
Sponsored by Wageningen University · Not applicable, Interventional, and Prevention
The overall aim of the project is to provide proof-of-principle that biofortification of cassava with vitamin A is a viable strategy to improve vitamin A status of deficient populations.
Rationale: Vitamin A deficiency is still common in developing countries and has been proven difficult to combat. A promising approach is to replace common crops with varieties that are naturally richer in vitamin A, which is referred to as biofortification. For cassava, yellow β-carotene rich varieties have recently been introduced in Kenya, and these varieties are now ready to be tested for their efficacy to improve vitamin A status in humans.
Objective: The primary objective is to measure the effect of daily consumption of provitamin A biofortified cassava (providing 50% of the age-specific RDA) on vitamin A status in children aged 5-13 years with mild to moderate vitamin A deficiency in Kenya. To determine the bioefficacy of provitamin A carotenoids from biofortified cassava relative to that of a daily B-carotene supplement (comparison with positive control group). Secondary objectives are: 1) to measure the effect of the intervention on immune function indicators and morbidity; 2) to determine to what degree the serum retinol response to the intervention depends on serum concentrations of retinol and zinc at baseline; 3) to determine the effect of the intervention on functional indicators such as dark adaptation capacity, gut integrity, hematology indicators and thyroid status; 4) to determine the mediating effect of SNP's in the BCMO1 gene on treatment outcome.
Study design \& Study population : In this randomized controlled trial, school children aged 5-13 years living in the Kibwezi area, Kenya. Children will be selected from three (or four) primary schools in the area that have been pre-selected based on the prevalence of vitamin A deficiency, location and willingness to participate.
Intervention: After screening for eligibility and a 2-week run-in period (n=360) Children will be randomly allocated to three different treatments: 1) 400 g of yellow cassava providing \~50% of the RDA for vitamin A; and a placebo capsule; 2) 400 g of white cassava; and a placebo capsule; 3) 400 g of white cassava and a capsule containing 100 RAE of all-trans β-carotene.
Main study parameters/endpoints: The main outcome measure will be differences in serum retinol concentrations between groups. Other outcome measures include other vitamin A status indicators (β-carotene, retinol binding protein, transthyretin), immune function indicators, dark adaptation, iron status indicators, anthropometrics, gut integrity, and thyroid function.
67 studies on the registry are indexed under Vitamin A Deficiency; 7 are open to participants now.
This study's enrollment of 341 is above the median of 200 across 49 interventional studies indexed under Vitamin A Deficiency.
Browse Vitamin A Deficiency studies →Wageningen University is the lead sponsor of 153 studies on the registry; 15 are open to participants now.
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Exclusion Criteria:
Other: Yellow cassava
Other: White cassava
Other: White cassava
Daily provision of 375 g boiled yellow cassava for 18 weeks, 6 days/week Daily provision of placebo capsule for 18 weeks, 6 days/week
Daily provision of 375 g boiled white cassava for 18 weeks, 6 days/ week Daily provision of placebo capsule for 18 weeks, 6 days/ week
Daily provision of 375 g boiled white cassava for 18 weeks, 6 days/week Daily provision of B-carotene capsule (1400 µg B-carotene)
Change in serum retinol concentration
Time frame: Baseline, end of study (4 months)
Immune function indicators
neopterin, IL-2, IL4, IL10, IL13, TNF-a, IFN-γ, TGF-β in serum; IgA in saliva
Time frame: End of study (4 months)
Bioefficacy
Comparison of change in serum retinol between yellow cassava group and positive control (B-carotene supplement group)
Time frame: Baseline, end of study (4 months)
Functional indicators
Gut integrity, dark adaptation, morbidity
Time frame: End of study (4 months)
Thyroid function
Serum Tg, TSH
Time frame: End of study (4 months
Effect modification
Serum zinc, serum retinol, iron status, polymorphisms
Time frame: Baseline
Anemia
Hemoglobin
Time frame: End of study (4 months)
The record gives a start of May 2012, a primary completion of Nov 2012 and a completion of Nov 2012. It does not say whether these dates are actual or estimated.
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This study is completed, as verified in Nov 2022. You cannot join it, but the record below documents what was studied.
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