NCT05385042

Iron and Immune Response to Vaccine (IRONMUM)

Iron Supplementation and Immune Responses to Maternal Vaccination in Pregnant Women

• Status: Completed
• Phase: N/A
• Study type: Interventional
• Enrollment: 171 (actual)
• Sponsor: University of Oxford · Academic / Other
• Sex: Female
• Age: 18 Years
• Healthy volunteers: Accepted

Summary

Iron deficiency causes anaemia and is common in pregnant women especially for those living in tropical regions where a high burden of infection and poor nutrition can compromise health. Low iron has been recognized as a cause of poor immune response because the group of cells that need to increase to make the immune response need iron to function. Vaccination is an important part of care during pregnancy because components of the immune response can cross the placenta and protect the young infant. More recently COVID-19 vaccination has also been recommended for pregnant women due to their higher risk of dying from this infection. Deeper investigation of whether low iron results in poor immune response is needed because the vaccines may not be providing as much protection as needed. The World Health Organization also recommends nutritional iron supplements in pregnancy and whether these improve immune response to vaccines is also not known. This study aims to test the body's immune response to recommended vaccines in pregnant women (tetanus and diphtheria (combination) and COVID-19 vaccine (if indicated)) who are anaemic and receiving iron supplements and compare their response to women who are not anaemic, who only receive a preventive, lower dose of supplement.

Detailed description

This is a prospective interventional open label cohort study with an exploratory framework. After assessment of gestation by routine ultrasound, women will be invited to participate if they have a viable, singleton pregnancy with a gestation \< 28 weeks. Consenting pregnant women will be enrolled at first antenatal clinic \[7\] visit and receive tetanus and diphtheria immunisation after confirmation of vaccination history, and SARS-CoV-2 immunisation (first dose if indicated). All women will be classified as non-anaemic or anaemic based on haematocrit (Haematocrit\<33% in first trimester (defined \<14 weeks) and Haematocrit \<30% in 2nd trimester (defined 14 to \<28 weeks)). Women will be assigned to groups and receive prophylactic (non-anaemic) or treatment (anaemic) doses of nutritional supplements, respectively, as per routine practice. These supplements will be provided daily for 3 months (12 weeks) and women will be followed up at day 7, 1 month (day 28), 2 and 3 months. There after they will follow routine antenatal care until birth when a cord blood sample will be taken. Mother and infant blood samples will be taken at the 2 months post-partum visit when the newborn attends for routine vaccinations of the expanded program of immunisation. Immunological and haematological responses will be measured by venous blood sampling and finger-prick sampling (routine at the clinics) at study visits; as will adverse events in relation to nutritional supplements by monthly questions using a checklist of common reactions to oral iron. The Adherence Starts with Knowledge (ASK-12) instrument has been modified and used in this population and will be compared to the Haematocrit levels, the pill count and adverse events, as a measure of adherence. IRONMUM study is funded by Procter and Gamble. The grant reference number is Thailand-UK-IRONMUM-2021-01.

Conditions

• Pregnancy Related

Interventions

Type	Name	Description
DIETARY_SUPPLEMENT	Sangobion and Thiamine Hydrochloride	Prophylactic dietary supplements: 1 capsule of Sangobion + separate Thiamine Hydrochloride tablet 100mg per day for 12 weeks. Then non-anaemic pregnant women will continue with prophylactic nutritional supplements until delivery.
DIETARY_SUPPLEMENT	Sangobion, Thiamine hydrochloride and Vitamin B12	Treatment dietary supplements: 3 capsules of Sangobion + separate Thiamine Hydrochloride tablet 100mg, Vit B12 100mcg per day for 12 weeks. If experience a therapeutic increase of 3% Haematocrit within 28 days (responders), they will continue with prophylactic nutritional supplements until delivery. If no affect in Haematocrit level within 28 days (non-responders; defined by trimester of diagnosis), they will be investigated for their serum ferritin and if this is low (\<15ng/mL) intravenous (iv) iron supplement (Venofer®) will be provided. The dose will be calculated for the individual concerned (required iron dose (mg) = (2.4 x (target Hb of 11g/dL (Ht 33%) x pre-pregnancy weight (kg) +1000mg for replenishment of stores). Doses will be administered by slow iv infusion 200 mg per dose (maximum of 3 doses per week). Following treatment they will continue with prophylactic nutritional supplements.

Timeline

• Start date: 2022-06-18
• Primary completion: 2025-07-22
• Completion: 2025-07-22
• First posted: 2022-05-23
• Last updated: 2026-03-24

Locations

1 site across 1 country: Thailand