Priority setting for improved influenza vaccines: a multi-criteria decision analysis

Seasonal influenza vaccines reduce global morbidity and mortality but remain underused in low- and middle-income countries (LMICs). This study was part of the World Health Organization's Full Value of Improved Influenza Vaccines Assessment (FVIVA) and explored LMIC decision-makers' priorities and preferences for improved influenza vaccines (IIVs) to enhance their adoption.

A multi-criteria decision analysis (MCDA) to evaluate IIVs was conducted in Kenya and Thailand. Criteria were defined through a literature review and expert opinion, then refined in an online workshop (WS1) with national stakeholders. Criteria weights and scores were elicited in a second workshop (WS2) using a swing weighting approach and a bisection approach, respectively. Results were validated against one current influenza vaccine and three hypothetical IIVs for which a performance matrix had been developed. WS1 was also conducted in 11 other countries to gain a more generalizable understanding of product preferences regarding IIVs.

In Kenya and Thailand, 7 criteria were included in the MCDA, 6 of which were shared: vaccine efficacy, duration of protection, breadth of protection, serious adverse events, temperature requirements, and shelf life. Scores and weights were also similar across criteria in both countries.

Results from 13 countries identified a core set of decision-making criteria for IIVs. MCDA was a well-accepted and feasible approach to for evidence-based prioritization and optimisation of vaccine portfolios in national immunisation programmes. Future development efforts should focus on improving IIVs based on country-identified criteria.