NCT05919472

Effects of Oral Iron Supplementation on Vaccine Response in Iron Deficient Kenyan Women

Effects of Oral Iron Supplementation Before vs. at Time of Vaccination on Immune Response in Iron Deficient Kenyan Women

• Status: Completed
• Phase: N/A
• Study type: Interventional
• Enrollment: 180 (actual)
• Sponsor: Nicole Stoffel · Academic / Other
• Sex: Female
• Age: 18 Years – 49 Years
• Healthy volunteers: Accepted

Summary

Iron deficiency (ID) anemia (IDA) is a global public health problem, with the highest prevalence in Africa. Vaccines often underperform in low- and middle- income countries (LMIC), and undernutrition, including ID, likely plays a role. Recent studies have shown the importance of iron status in vaccine response. Intravenous iron given at time of vaccination improved response to yellow fever and COVID-19 vaccines in IDA Kenyan women. Whether oral iron treatment would have a similar beneficial effect on vaccine response is uncertain. Also, timing of oral iron treatment needs further investigation. The co-primary objectives of this study are to assess 1) whether IDA in Kenyan women impairs vaccine response, and whether oral iron treatment improves their response; 2) the timing of oral iron treatment to improve vaccine response (prior to vaccination vs at time of vaccination). We will conduct a double-blind randomized controlled trial in southern Kenya to assess the effects of iron supplementation on response to three single-shot vaccines: Johnson \& Johnson COVID- 19 (JJ COVID-19), the quadrivalent meningococcal vaccine (MenACWY) and the typhoid Vi polysaccharide vaccine (Typhim Vi). Women with IDA will be recruited and randomly assigned to three study groups: group 1 (pre- treatment) will receive 100 mg oral iron as ferrous sulfate (FeSO4) daily on days 1-56; group 2 (simultaneous treatment) will receive matching placebo daily on days 1-28, and 200 mg oral iron as FeSO4 daily on days 29-56; and group 3 (control) will receive matching placebo daily on days 1-56. Women in all groups will receive the JJ COVID-19 vaccine, the MenACWY and the Typhim Vi vaccine on day 28. Cellular immune response and serology will be measured at 28 days after vaccination in all groups.

Conditions

• Iron Deficiency Anemia

Interventions

Type	Name	Description
DIETARY_SUPPLEMENT	Oral iron supplementation (pre-treatment)	Iron supplements as 200 mg oral iron as FeSO4 given on alternate day on days 1-56
BIOLOGICAL	COVID-19 vaccine	Johnson \& Johnson COVID- 19 (JJ COVID-19) vaccination given on day 28 to all participants
BIOLOGICAL	MenACWY vaccine	MenACWY vaccination given on day 28 to all participants
DIETARY_SUPPLEMENT	Oral iron supplementation (simultaneous treatment)	Iron supplements as 200 mg oral iron as FeSO4 given on alternate day on days 28-56
BIOLOGICAL	Typhim Vi vaccine	Typhim Vi vaccination given on day 28 to all participants

Timeline

• Start date: 2023-07-01
• Primary completion: 2024-07-16
• Completion: 2024-07-16
• First posted: 2023-06-26
• Last updated: 2025-12-26

Locations

1 site across 1 country: Kenya