19 November 2020
The results of a phase 2/3 single-blind, randomised controlled trial of the ChAdOx1 nCoV-19 vaccine against COVID-19, being developed by researchers at Oxford University and AstraZeneca, have been published in The Lancet today. This part of the trial concentrates particularly on examining the safety and effectiveness of the vaccine when given to different age groups.
In response, the British Society for Immunology has released the following statement:
Professor Deborah Dunn-Walters, Chair of the British Society for Immunology COVID-19 and Immunology taskforce, and Professor of Immunology at University of Surrey, said:
“Ensuring the safety and effectiveness of potential COVID-19 vaccine candidates is of the utmost importance. We know that our immune systems change as we age, which results in a reduced ability to fight infections - one of the reasons that COVID-19 has taken such a high toll on our older population. This decline in immune function in older adults can also result in a reduced response to vaccination. As the British Society for Immunology recent report recommended, it’s imperative that all COVID-19 vaccine trials should prioritise research into understanding vaccine effectiveness and safety profile in older people, one of the groups of people most in need of protection against infection from SARS-CoV-2. This includes examining how to ensure maximum vaccine effectiveness in older people by investigating dosing schedule, formulation, boosting and vaccination routes.
“It’s positive to see today’s study published in The Lancet running a phase II trial for the ChAdOx1 nCoV-19 vaccine in an older age group with a median age of 73. While this is an ongoing study, the initial results are encouraging. The vaccine appears to be well tolerated in all age groups, with older individuals reporting fewer side-effects. At one month after giving two doses of the vaccine, all age groups showed a similar level of antibody response. Some age-related differences in the cellular immune response were recorded which require further investigation. However, if the immune measures recorded in the phase II part of this study correlate with protection from SARS-CoV-2, then we would expect positive outcomes from the phase III trial.
“Developing new vaccines is a highly complicated process and this study is just one piece of the puzzle. Although the results of this phase II trial are an important step forward, they are not the end of the story and there is still much more we need to find out. For example, how effective is this vaccine in older people who have other health conditions? In order to thoroughly assess that the safety and effectiveness profile of this vaccine for widespread use against SARS-CoV-2, we now need to await the results of this vaccine’s much larger phase III clinical trial. This is currently underway, involving thousands of participants, and will deliver more robust information on the safety and effectiveness profile of the ChAdOx1 nCoV-19 vaccine.”
Read the full paper that this statement is in response to:
Ramasamy et al. 2020 Safety and immunogenicity of ChAdOx1 nCoV-19 vaccine administered in a prime-boost regimen in young and old adults(COV002): a single-blind, randomised, controlled, phase 2/3 trial. The Lancet DOI: 10.1016/ S0140-6736(20)32466-1
You can read the recent report from the British Society for Immunology on 'The ageing immune system and COVID-19'