Background: Anaemia in pregnancy is a public health burden with high incidence in Africa. Currently high dose oral iron is recommended for treatment of mild to moderate anaemia and blood transfusion for severe anaemia. The high dose oral iron is often poorly tolerated and associated with several side effects. Various parenteral iron preparations are now available for treatment of iron deficiency anaemia (IDA). The earliest of these, iron dextran is not commonly used because of its potential to cause anaphylactic reactions. Newer preparations have been found to be safer and their use for treatment of IDA is currently being evaluated.

Objective: This study sought out to compare the effectiveness of intravenous ferric carboxymaltose (intervention) versus oral ferrous sulphate (control) for treating IDA in pregnancy and to compare the tolerability, safety and the cost-effectiveness of intravenous versus oral iron among pregnant Nigerian women with moderate and severe IDA at 20-32 weeks' gestation.

Methodology: This study will be a hybrid Type 1 effectiveness-implementation design. 1056 eligible and consenting pregnant women with anaemia at 20 - 32 weeks gestation will be recruited. They will be randomized into either of 2 groups. Group A will have intravenous ferric carboxymaltose 20mg/kg to a maximum of 1000mg in 200mls of normal saline infusion over 15 - 20 minutes at enrolment. Group B will have oral ferrous sulphate 200mg (65mg elemental iron) thrice daily from enrolment till delivery. They will be followed up through delivery and until 6 weeks post partum. Their haemoglobin concentration, full blood count, serum ferritin and serum transferrin will be assayed at specific intervals using standard laboratory techniques. Depression will be assessed at each visit using Edinburg Postnatal Depression Scale. Cost effectiveness analysis will also be done at each visit. The primary outcome measure will be incidence of maternal anaemia and rise in haemoglobin level. Secondary outcome measures will include safety and tolerability of trial drugs, severe maternal events, incidence of infant low birth weight and incidence of depression. Statistical analysis will be done using STATA version 16.0 statistical software (STATACorp, Texas, USA).

1.0 INTRODUCTION Anemia in pregnancy (AIP) remains a critical global health problem especially in low- and middle-income countries (LMICs), affecting 46% of pregnant women in Africa and 49% in Asia. AIP is defined as a venous blood hemoglobin concentration of <11 g/dl in a pregnant woman. Iron deficiency anemia (IDA) is the commonest cause of AIP, accounting for 50-75% of AIP. Antenatal maternal anemia has significant implications on both maternal and neonatal outcomes, including maternal mortality from hemorrhage and morbidity from infections, and neonatal low birth weight and prematurity. It has also been associated with an increased risk of depression.

In most LMICs, including Nigeria, routine treatment of IDA in pregnancy is with oral iron preparations, due to fears of serious adverse reactions from parenteral iron, including anaphylaxis, and the belief that oral iron is equally effective. Parenteral, especially intravenous, iron is also more expensive, and it is not clear whether its benefits are worth the cost. In settings like Nigeria, where most people still pay out-of-pocket for healthcare, cost effectiveness is particularly important. However, apart from the side effects caused by oral iron, it also takes longer to correct the anemia, and in cases where patients are unable to absorb iron, oral intake is rendered ineffective. Reservations on use of parenteral iron have been due largely to experience with high molecular weight iron dextran preparations, which had a relatively high incidence of anaphylactic reactions. Fortunately, there are now several safe parenteral iron preparations, such as iron sucrose, iron polymaltose, ferric carboxymaltose (FCM) and iron isomaltoside.

2.0 AIMS AND OBJECTIVES Aims: To determine the comparative effectiveness of intravenous FCM (intervention) versus oral ferrous sulphate (control) for treating iron deficiency anemia in pregnancy and to compare the tolerability, safety, and the cost-effectiveness of intravenous versus oral iron among pregnant Nigerian women with moderate and severe IDA at 20-32 weeks' gestation. It also aims to evaluate the acceptability, feasibility, and fidelity of use of intravenous FCM for treating IDA.

Objectives

1. To determine effect of intravenous FCM on the prevalence of maternal anemia at 36 weeks' gestation and on increase in hemoglobin concentration 4 weeks after administration, compared with oral ferrous sulphate (FS) in pregnant women with IDA.
2. To determine effect of intravenous FCM on incidence of postpartum hemorrhage, sepsis, shock, need for blood transfusion, prevalence of depression and other maternal clinical outcomes, compared with oral FS in pregnant women with IDA.
3. To determine effect of intravenous FCM on the incidence of low infant birthweight, prematurity, stillbirth, and neonatal mortality, and on breastfeeding and immunization, compared with use of oral FS in pregnant women with IDA.
4. To measure implementation outcomes of intravenous FCM including its acceptability, feasibility, and fidelity in the context in which the trial is being carried out.
5. To determine cost-effectiveness of intravenous FCM compared with oral FS in treatment of IDA in pregnancy.

3.0 STUDY DESIGN: This study is a multicenter, parallel, open label, individually randomized controlled trial, with women allocated in a 1:1 ratio in conjunction with a cost-effectiveness analysis.

3.1 Study setting and site selection: The study will be implemented in two most populated states in Nigeria; Kano State in North-West and Lagos State in South-West zone. One tertiary, two secondary and two primary healthcare facilities have been purposively selected from each state, making 10 targeted facilities based on antenatal patient flow, number of deliveries and proximity of all three levels of care to facilitate an effective two-way referral system.

3.2 Sample size calculations: At 5% significance and precision level, 1,056 pregnant women (528 in each study arm) are required to detect a difference in improvement in prevalence of AIP at term by 14%, between control group (70% corrected) and intervention group (84% corrected), as seen in a multi-country international study in Europe, Asia, and Australia (30) at 90% power, adjusting for 15% attrition and protocol violations (31).

3.3 Randomization: At enrolment, eligible participants will be randomized to one of the two treatment groups using a web-based randomization software known as 'Sealed envelope' in a 1:1 ratio in blocks stratified according to center.

3.4 Study intervention: Eligible pregnant women randomized to intervention arm (FCM) will be admitted on a day care basis for treatment initiation and will be given intravenous FCM in a single dose of 20mg/kg up to a maximum of 1000mg in 200 ml 0.9% sodium chloride infusion over a minimum of 15 - 20 minutes. Thereafter, they will be observed for a minimum of 30 minutes before being allowed to go home.

The pregnant women randomized to the control arm (FS) will be given one 200mg tablet of ferrous sulphate containing 65mg of elemental iron, three times daily till 6 weeks post-delivery. The women will be sent daily reminders by text messages, questioned on compliance at each visit and asked to bring in their empty sachets for sighting and pill count.

After delivery, all study participants will be tested for anemia with Hemocue before discharge. Those with hemoglobin concentration less than 11g/dl will be treated as per standard practice i.e., with FS 200mg tds, vitamin C 100mg tds and folic acid 5mg daily.

All study participants in both arms will receive 5mg folic acid daily, vitamin C 100mg tds, and followed from enrollment till delivery and for 6 weeks post-partum. They will be seen 4-weekly till 28 weeks, 2 weekly till 36 weeks and weekly till delivery and then at 2, 4 and 6 weeks postpartum.

3.5 Malaria Treatment and Prevention: Participants will be screened at enrolment for malaria parasitemia with SD BIOLINE Malaria Ag P.f and treated with Artemisinin based combination therapy if positive for malaria parasite. Thereafter, intermittent preventive treatment for malaria will be administered with three doses of three tablets of Sulphadoxine pyrimethamine (500/25) monthly except if patient is allergic to sulphonamides, in which case, patient will be placed on monthly artemisinin-lumefantrine (treatment dose). All pregnant women will also be given long lasting insecticide treated bed nets and counseled on usage.

3.6 Physical examination: Full physical examinations will be performed at baseline, and at each visit. The initial evaluation will also include measurement of patient's weight and blood pressure.

3.7 Laboratory evaluations: These will include:

• Full blood count at enrollment, 4 weeks post enrollment, 36 weeks' gestation, day of delivery and 6 weeks' postpartum.
• Malaria rapid diagnostic test (RDT) with SD BIOLINE Malaria Ag P.f at enrolment and if symptomatic for malaria at any time.
• Hemoglobin concentration with the Hemocue haemoglobinometer at enrolment and every study visit. The first will be used for enrollment.
• Iron profile: This will comprise serum ferritin, serum iron, total iron binding capacity and transferrin saturation at 4 weeks post enrollment, 36 weeks' gestation, day of delivery and 6 weeks postpartum. Only serum ferritin will be done at enrolment.
• Serum phosphate: maternal phosphate level at enrollment, 4 weeks post enrollment, on day of delivery and 6 weeks postpartum; and cord blood phosphate on day of delivery.

All samples aside point of care tests (POCT) will be analyzed at Synlab (an internationally accredited medical laboratory).

3.9 Visit schedules and assessments

• The participants' subsequent clinic visits will be scheduled to hold every 4 weeks till 28 weeks' gestation and every 2 weeks till 36 weeks, then weekly until delivery. Thereafter, they will be seen at 2, 4 and 6 weeks postpartum. Reminders on appointments will be sent by SMS to all participants 24 hours before scheduled visit.
• Women diagnosed as having depression using Edinburg Postnatal Depression Scale (EPDS) will be referred to a psychiatrist for further management.

4.0 DATA ANALYSIS PLAN Data analysis will be by intention-to-treat. Categorical variables will be expressed as frequencies and percentages. For continuous variables, a Shapiro-Wilk test of normality will be performed, and normally distributed data will be presented as means ± SD, while non-normally distributed data will be presented as median and interquartile range (IQR). The risk of occurrence of IUGR, perinatal death and other key outcome variables will be computed and compared in both groups. A multivariate regression analysis will be performed to determine the odds of each of the key outcomes among women who received the intervention with respect to those who did not, after controlling for common confounders. This will be presented as regression coefficients and their 95% confidence intervals. Level of significance will be set at 5%. Post-regression analysis will be performed to determine the goodness-of-fit of the final model. STATA version15.0 (Stata Corp LP, College Station, TX, USA) will be used for statistical analysis.

5.0 MONITORING PLAN - There will also be a Steering committee, Clinical Trial Monitors, and a Data and Safety Monitoring Committee (DSMC).

6.0 ETHICS AND RESEARCH INTEGRITY: This trial has been registered in Pan African Clinical Trials Registry (PACTR202012843695208), International Standard Randomized Controlled Trial Number registry (ISRCTN63484804) and Nigeria Clinical Trial Registry (NCTR, 86233598).

Ethical approvals have been obtained from the National Health Research and Ethics Committee of Nigeria (NHREC), and HREC of both teaching hospitals and health care boards in both states. All study investigators and site coordinators are GCP certified. The research nurses will also be GCP certified.

All participants will sign informed consent form prior to enrolment. Personal data of each participant will be kept strictly confidential and will be stored securely in a central electronic database. Only authorized personnel will have access to the data of all participants collated centrally. The statistician will be granted access to the electronic database during statistical analysis or at any other time the PI might require her to review the data. All research drugs and investigations relating to the research will be offered free.

This research poses minimal or no risk to both mother and baby. Blood specimen collection might cause minimal discomfort in form of pain and care will be taken to minimize this. The intervention drug FCM is known to be safe in pregnancy and is not expected to have significant adverse effects on participants.

All research staff will be adequately trained to monitor, recognize, and manage any significant adverse drug event. In the rare instance of any moderate/severe adverse drug events such as hypophosphatemia and anaphylaxis, trained research staff will effectively resuscitate and transfer care to higher level health facility for adequate care at no cost to the participant.

All participants will receive other routine medication (malaria prophylaxis, tetanus toxoid prophylaxis and folic acid supplementation) as normally prescribed. Malaria prophylaxis, insecticide treated net and folic acid will be provided to the participants all through pregnancy. The participants will enjoy equal rights and quality care all through the duration of the research.

Environmental issues are not applicable to this study. 7.0 DISSEMINATION STRATEGIES The study findings will be presented at conferences (both international and local). Findings will be published in high impact peer reviewed journals. Charts will be created from findings, and these will be used in counselling pregnant women at the various antenatal clinics on complications associated with anemia and preventive measures that may be employed. The researchers will issue press release on study finding.

Inclusion Criteria:

• Pregnant women aged 15 to 49 years old between 20*- and 32**-weeks' gestational age.
• Baseline (enrollment) laboratory-confirmed moderate or severe anemia (Hb < 10g/dl).

Exclusion Criteria:

• Medically-confirmed significant bleeding, major surgery or received blood transfusion within the last 3 months.
• Severe symptomatic anemia needing urgent correction with blood transfusion.
• Anemia of other cause besides IDA e.g., Sickle cell anemia.
• Clinically-confirmed malabsorption syndrome.
• Hypersensitivity to any form of iron treatment.
• History of any immune related illness e.g., SLE, Rheumatoid arthritis.
• Preexisting maternal depression or other psychiatric illness.
• Severe allergic reactions such as severe asthma.
• History of severe drug allergy.

Pregnant females only are eligible to participate in the proposed research.

We will store the data and deposit it in 'Open Science Framework', after approval is obtained from the ethics committee. We will also provide metadata along with the data to describe it. No patient identifier will be included in data shared. Potential new users may access our data including the metadata on the 'Open Science Framework'. We will share the data at the time of publication of our first paper. The assigned DOI number, the OSF website details and our approach to data sharing will be included as an appendix to all publications emanating from this research to facilitate accessibility to our data and metadata. We will also share these at any conference presentation both international and local, and also on our study website to facilitate access to it by other researchers.

IPD sharing will commence at the time of first publication or within 6 months of study completion. The duration of IPD sharing will be 2 years, starting tentatively on 1st January 2024 and ending in 31st December 2025.

The principal investigator will bear overall responsibility for this data and will be responsible for deciding whether to supply research data to a potential new user. The CMUL HREC will provide an independent oversight function.

2. Data will be made available at the time of publication, at the latest. Depending on the nature of the data itself, data may be made available earlier, either on an individual basis to interested researchers and/or potential new collaborators.

3. We will ensure that our informed consent forms clearly spell out and seek consent for future data sharing. However, only de-identified data will be shared. I think we will need to clearly spell out the data sharing process.

4. All external users will sign and be bound by our data sharing agreements and will not be allowed to use the data for reasons other than stated in their application.

5. IPD sharing will be by open access on Open Science Framework during the period of IPD sharing.