Abstract

In resource-limited settings like Malawi, optimizing vaccine inter-dose intervals can improve logistical feasibility without compromising efficacy. While the Multi-Arm Multi-Stage Response Over Continuous Interventions (MAMS-ROCI) design has identified shorter treatment durations, its adaptation for longer intervals remains unexplored. Addressing this gap is critical to enhance vaccination efficiency in cholera outbreaks. We adapted MAMS-ROCI to identify the longest non-inferior interval for a two-dose cholera vaccine. Eight duration-response scenarios were simulated, with fractional polynomials modeling non-linear relationships. Performance was assessed via type I error and power. The design achieved >80% power for logistic and quadratic scenarios, identifying non-inferior intervals up to 14 weeks. Fractional polynomials captured smooth curves well but had reduced precision (17% true power) with abrupt changes. A sample size of 2,200–3,000 ensured robustness. MAMS-ROCI is viable for identifying optimal extended vaccine intervals when efficacy follows logistic or quadratic patterns. For complex responses, robust modeling or larger samples are recommended. This approach guides efficient vaccine scheduling in epidemic settings.

More details

School	: School of Natural and Applied Sciences
Issued Date	: 2025

Download full document