The role of real-world evidence for regulatory and public health decision-making for Accelerated Vaccine Deployment- a meeting report.

The COVID-19 pandemic underscored the need for rapid evidence generation to inform public health decisions beyond the limitations of conventional clinical trials. This report summarises presentations and discussions from a conference on the role of Real-World Evidence (RWE) in expediting vaccine deployment. Attended by regulatory bodies, public health entities, and industry experts, the gathering was a collaborative exchange of experiences and recommendations for leveraging RWE for vaccine deployment. RWE proved instrumental in refining decision-making processes to optimise dosing regimens, enhance guidance on target populations, and steer vaccination strategies against emerging variants. Participants felt that RWE was successfully integrated into lifecycle management, encompassing boosters and safety considerations. However, challenges emerged, prompting a call for improvements in data quality, standardisation, and availability, acknowledging the variability and potential inaccuracies in data across diverse healthcare systems. Regulatory transparency should also be prioritised to foster public trust, and improved collaborations with governments are needed to streamline data collection and navigate data privacy regulations. Moreover, building and sustaining resources, expertise, and infrastructure in LMICs emerged as imperative for RWE-generating capabilities. Continued stakeholder collaboration and securing adequate funding emerged as vital pillars for advancing the use of RWE in shaping responsive and effective public health strategies.

Evaluation of Heterologous Effects of Travel Vaccines in Colorectal Cancer: A Database Study and a Cautionary Tale.

Background and Aims: Recently, cholera vaccine use was shown to be associated with a reduced risk of death in patients with colorectal cancer (CRC). However, evidence on heterologous effects of travel vaccines is limited. The aim of this study was to study heterologous effects of travel vaccines in patients with CRC. Methods: We performed a retrospective database study on a cohort of CRC patients in Sweden and their postdiagnostic use of travel medications between July 2005 and December 2017. We obtained data from national registries on number of CRC diagnosis, death from CRC or other causes, age at diagnosis, and postdiagnostic use of travel vaccines and malaria prophylaxis. The Cox regression model was used to calculate incidence rate and incidence rate ratios of CRC-related and all-cause mortality by postdiagnostic travel medication status. Results: Two hundred ninety-five patients exposed to travel vaccines and malaria prophylaxis and 73,466 patients not exposed to travel medications were identified. CRC-related mortality was lowered in the exposed patients compared to the unexposed patients, irrespective of the travel medications used. The incidence rate ratios for CRC-related mortality and overall mortality were comparable. Conclusion: We postulated that patients in better health were likely to travel more frequently than patients with poor health, leading to a healthy user bias. The results suggested the same, as similar reduced mortality risks were found for all the investigated travel medications, lowering the biological plausibility of truly protective effect from post-therapeutic use of any of the travel medication studied. We advocate the use of multiple negative exposure controls and to exercise caution while drawing conclusions from travel vaccine research.