Microarray patches likely to reduce the operational costs of immunization: A Monte Carlo simulation study.

Development of microneedle array patches (MAPs) for potential use in immunization is ongoing, but the cost of manufacturing is expected to be higher than that of existing needle-and-syringe vial systems. The potential benefits of MAPs in reaching previously unvaccinated populations have been touted, but affordability, especially in low- and middle-income countries, remains an open question. In this study, we quantify the expected impact on operational costs of switching to MAPs for immunization for measles-rubella, human papilloma virus, and typhoid in both routine and campaign-based delivery modes. We endeavor to make a comprehensive estimate, including the costs of labor, syringes, waste management (i.e., sharps and trash), wastage (unused vaccine), freight and in-country cold chain transportation. We examined five potential use cases and our results show that in total, operational cost savings from a switch to MAPs are expected to range from a low of $0.24 per dose delivered (HPV, 1-dose vial, campaign) up to $0.61 per dose delivered (MR, 10-dose vial, routine). Excluding the allocated cost of labor, the estimated range of cost savings are $0.18 and $0.43, respectively. Confidence intervals are wide, due to the uncertainty in the assumptions, but in all five use cases tested, there was at least an 87 % probability of savings. These results show that operational savings from a switch to MAPs may offset at least part of the expected incremental manufacturing costs, which will make the transition more viable in settings with limited budget space. With this in mind, development agencies should continue to invest in MAPs technology and, if the product does come to market, use this evidence as part of total value of vaccines assessments and to inform investment strategies for implementation of vaccine MAPs, including alignment with policy makers.