Efficacy and Safety of COVID-19 Vaccines in Older People

Roy L. Soiza; Chiara Scicluna; Emma C. Thomson


Age Ageing. 2021;50(2):279-283. 

In This Article

Abstract and Introduction


Several vaccines against coronavirus disease 2019 (COVID-19) are on the cusp of regulatory approval. Their safety and efficacy in older people is critical to their success. Even though care home residents and older people are likely to be amongst the first to be vaccinated, these patient groups are usually excluded from clinical trials. Data from several Phase II trials have given cause for optimism, with strong antibody responses and reassuring safety profiles but, with the exception of AstraZeneca's vaccine, recruited few older people. Overall, the sparse data from Phase II trials suggest a reduction in both antibody responses and mild to moderate adverse events in well older people compared to younger participants. Many of the Phase III trials have made a conscious effort to recruit older people, and interim analyses of the Pfizer and Moderna vaccine have led to press releases announcing high degrees of efficacy. However, older people with co-morbidities and frailty have once again been largely excluded and there are no published data on safety and efficacy in this group. Although the speed and impact of the pandemic on older people with frailty justify an approach where they are offered vaccination first, patients and their carers and supervising health care professionals alike will need to make a decision on accepting vaccination based on limited evidence. Here we review the main candidate vaccines that may become available, with a focus on the evidence of safety and efficacy in older people.


As the world prepares for a mass roll-out of newly approved coronavirus disease 2019 (COVID-19) vaccines, older people with frailty are taking centre stage. Recognising that this group had borne the brunt of the pandemic, with most excess deaths occurring in the oldest age groups,[1] the UK government's Vaccines Task Force strategy focussed on vaccines expected to elicit a good immune response in older people, stating it was 'essential' that they worked in this age group.[2] Residents in care homes and older people with co-morbidities are likely to be among the first to be vaccinated. But what is the evidence that the vaccines are safe and effective in this population? Here we briefly review the main candidate vaccines, with a focus on the evidence of their safety and efficacy and its relevance to the older population.

A summary of the main COVID-19 vaccines being developed for potential use is shown in Table 1. They differ in their mechanism of action, which may be of relevance to their safety and efficacy in older people.