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The emergence of SARS-CoV-2 has burdened health systems worldwide. COVID-19 still poses a threat to global health, with over 67 000 new fatalities a week, as of February, 2022.1 Additionally, the measures to contain COVID-19 take an enormous social and economic toll.

Vaccination is a highly cost-effective tool to curtail cases in epidemic and pandemic infectious diseases. New COVID-19 vaccines have been developed, tested, and registered at a remarkable pace. Currently, there are nine COVID-19 vaccines that are used widely, effectively reducing infection, severe disease, and death worldwide.2 Real-world data from Israel, the UK, Sweden, and the USA, showed that full vaccination with the BNT162b2 (Pfizer–BioNtech) or mRNA-1273 (Moderna) vaccine protected adults from 61% to 92% against infection, 80–87% against hospitalisation, and 85% against death for the viral variants that were prevalent at the time of conducting these studies.3

Although highly effective vaccines are available and have a proven effect on pandemic control, less than 15% of people in low-income countries have been (partially) vaccinated so far.4 This number is in stark contrast to high-income countries, in which more than 180 vaccinations per 100 citizens have been given.4 This leaves a staggering 2·7 billion people still to be vaccinated globally. The COVID-19 Vaccines Global Access (COVAX) initiative aimed to provide enough vaccines to vaccinate 40% of the adult population of 92 lower income economies participating in the COVAX Advance Market Commitment by the end of 2021, but reached only 20% by the end of the year.5 The delay in vaccination leads to enormous preventable morbidity and mortality and puts more strain on health-care systems that were already heavily burdened before the pandemic.6

Increasing access to vaccines in low-income and middle-income countries (LMICs) is a complex challenge with limited supplies of vaccines, vaccine nationalism in high-income countries,7 vaccine hesitancy, and complications in distribution and registration6,  8 all playing a part. Although these problems require societal, political, logistical, and infrastructural solutions, scientific justification for alternative dose-sparing strategies are needed to facilitate resolution of shortages.

Despite tremendous efforts, worldwide COVID-19 vaccination coverage is lagging. To rapidly provide solid scientific justification for different dose-sparing strategies, joint coordinated action involving both public and private parties is needed. With this Viewpoint, this paper shares examples of approaches to vaccine dose-sparing that have previously been evaluated in clinical trials to improve vaccine availability and reflect on the origin of their funding. With a focus on the current COVID-19 pandemic. The study stresses the need for expedited testing of vaccine dose-sparing strategies in endemic or epidemic infectious diseases.