Efficacy and safety of COVID-19 vaccines in older people

Abstract

Several vaccines against COVID-19 are on the cusp of regulatory approval. Their safety and efficacy in older people is critical to their success. 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 more 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.

Physical Activity Patterns, Psychosocial Well-Being and Coping Strategies Among Older Persons with Cognitive Frailty of the “WE-RISE” Trial Throughout the COVID-19 Movement Control Order

“…Seeing as the ageing population with frailty has been the most heavily impacted by the pandemic, it can be assumed that older persons would most likely be prioritized for vaccination. 50 The developed COVID-19 vaccines are new and its efficacy amongst the older population has yet to be determined. Older persons with frailty and those with comorbidities have been excluded in the majority of the vaccine study trials, despite being the most vulnerable to infection.…”

“…Older persons with frailty and those with comorbidities have been excluded in the majority of the vaccine study trials, despite being the most vulnerable to infection. 50 Taking immunosenescence into consideration, theoretically the vaccines may be less effective in older persons as a result of inadequate antibody levels. 50 With the uncertainty of how the immune system may response to the vaccine, there is a possibility of increasing overall risk to adverse outcomes especially among the already predisposed older persons with frailty.…”

“… 50 Taking immunosenescence into consideration, theoretically the vaccines may be less effective in older persons as a result of inadequate antibody levels. 50 With the uncertainty of how the immune system may response to the vaccine, there is a possibility of increasing overall risk to adverse outcomes especially among the already predisposed older persons with frailty. 50 Therefore, preventing physical inactivity and boosting the body’s immunity via engagement in regular exercise and functional activities could possibly mitigate these potential adverse outcomes.…”

Prior COVID-19 Infection and Antibody Response to Single Versus Double Dose mRNA SARS-CoV-2 Vaccination

“…Notwithstanding the size of our study cohort, yet larger-sized samples are needed for sufficient statistical power to examine differences across demographic and clinical subgroups that are known to exhibit variation in antibody response following vaccination. 15–17…”

Physical activity: A coadjuvant treatment to COVID-19 vaccination?

“…Ensuring vaccination efficacy and safety is critical, particularly for the most vulnerable population segments such as frail older adults. Even though these individuals will likely be among the first to be vaccinated and evidence to date suggests a high efficacy of most COVID-19 vaccines in both old and young individuals ( Soiza et al, 2021 ), scarcer evidence is available for very old frail adults with multiple comorbidities, a population segment sparingly included in clinical trials ( Soiza et al, 2021 ; van Marum, 2020 ). Although at this point there is not enough evidence to discern whether older adults might present a lower antibody response to COVID-19 vaccination ( Soiza et al, 2021 ), previous data suggests a negative influence of age on the effectiveness of influenza vaccination ( i.e.…”