Effect of bovine lactoferrin on seroconversion following polio vaccine administration in children: protocol for a double-blinded randomised controlled trial

Introduction: The oral polio vaccine (OPV) has substantial results in eliminating wild poliovirus and the vaccine of choice in polio eradication. However, the mucosal immunity induced by the OPV is still uncertain. Literature has shown that bovine lactoferrin (BLF) is a safe and useful protein found in cow's milk with extraordinary antimicrobial, antiviral, antiinflammatory and immune-modulatory functions that help children's gut to fight against micro-organisms like poliovirus. However, limited data exist regarding the effect of BLF on polio vaccine immune response. The primary objective is to evaluate the effect of BLF in enhancing mucosal and humoral immunity in children following the administration of oral and inactivated polio vaccines.

Methods and analysis: This is a two-arm double-blinded randomised controlled trial comparing 462 neonates (231 in both groups) receiving either BLF or placebo with breast milk. The intervention is administered from day 1 till 6 weeks of age to a full-term healthy singleton newborn born at the Aga Khan University Hospitals, Karachi, Pakistan. The primary outcome is the seroconversion, 1 month after the receipt of two doses of OPV (at 10 weeks). For descriptive statistical analysis, Stata will be used, the frequency with percentages will be reported to describe baseline characteristics of the participants. A χ² test will be used to compare categorical variables and a simple t test to compare continuous variables. The proportion of seroconversion and shedding will be compared using χ² test or Fisher's exact test.

Ethics and dissemination: The Ethics approval has been granted by the Ethics Review Committee (ERC) of Aga Khan University for the proposed trial (ID: 2019-1955-5013). Furthermore, the National Bioethics Committee (NBC) of Pakistan has also approved the study for human subject research (ID: 4-87/NBC-443/19/669). Study findings will be disseminated through presentations at scientific conferences and educational practice workshops and will be published in an international peer-reviewed scientific journal.

Trial registration number: NCT04432935; ClinicalTrials.gov.