UK seeks to 'accelerate and optimize' clinical development of pandemic vaccines

The UK Vaccine Taskforce (VTF) notes the UK faced an ‘enormous challenge’ in delivering a large number of vaccine trials this year: given the unprecedented speed and intensity of COVID-19 vaccine development. In July, it launched ‘the world’s first national citizen registry’: where any member of the public can sign up and register their interest in participating in any upcoming trials. To date around 360,000 people have signed up.

“Without this NHS registry the UK would not have been able to enrol its trials so quickly and generate the necessary safety and clinical efficacy data rapidly,” ​says the UK government, which launched the taskforce in May this year with the remit of ensuring the UK has access to COVID-19 vaccines as possible.

Thousands have been recruited into Phase 3 vaccine trials including Oxford/AstraZeneca, Novavax and Janssen; as well as AstraZeneca antibody trials to date, and more are expected to be approached for all phases of vaccine trials starting in 2021.

To encourage the UK public to sign up to this citizen registry, the VTF funded a targeted strategic communications campaign to launch the initiative and to attract those most at risk to sign up.

Around 33% of registrates are aged 60+. However, only 8% of registrants are from black, Asian and minority ethnic backgrounds: which does not reflect UK demographics. Specific communications campaigns are being run to try and attract more people from these communities.

The VTF believes this engagement with clinical trials can continue past the current pandemic: although notes it will take extra effort to ensure this happens.

“94% of those who have signed up to date have indicated willingness to be approached for trials other than COVID-19 vaccine trials and communications with those that have signed up indicate that levels of engagement are very high,"​ says the government as it releases a report on the progress of the VTF this month. "Currently “open rates” for a regular newsletter to volunteers on the registry are 80%. ​

“It is inevitable that engagement levels will decrease once vaccine deployment begins and therefore continued communications and engagement with these volunteers become even more important. This digital approach to building the NHS citizen registry provides an enduring legacy for future vaccine development and highlights again the value that the UK can bring to both global pandemic vaccine development as well as more broadly.”​

Human challenge studies

The UK has set out plans to start a Human Challenge Programme for COVID-19 in the new year: a collaboration between Imperial College London, the government’s Department for Business, Energy and Industrial Strategy (BEIS), clinical company hVIVO and the Royal Free London NHS Foundation Trust.

Human challenge studies – where volunteers are deliberately infected with the coronavirus – can increase understanding of how SARS-CoV-2 works and speed up vaccine development.

If approved by regulators and ethics committees, the trials​ ​- backed by a $43m government investment - will be the first in the world for coronavirus. The first results could be expected in May.

The aim of the UK challenge studies will be twofold: firstly to ascertain the level of virus that causes an infection; and secondly to assess the efficacy of vaccine candidates.

“In addition to running large placebo-controlled efficacy studies it is important to gain information about the coronavirus as we go forward. We do not yet know enough about the behaviour of the virus and the impact it has in different populations," ​notes the government report.

“Human challenge studies in flu revealed critical information and data about the infectivity of subjects prior to their showing symptoms and this was only discovered through the tightly controlled human challenge studies. ​

“Such studies could help define the immunopathogenesis of COVID-19, duration of vaccine-induced immunity and correlates of protection in healthy populations. ​

“Once the SARS-CoV-2 Human Challenge model has been established in early 2021, the VTF has secured the first three slots to run clinical trials on the most promising new vaccines ahead of everyone else. The model can be used as a ‘fast to fail’ approach to select the most promising vaccines faster and optimising investment. ​

Regardless of whether the first wave of vaccines are successfully licensed or not, follow on vaccines are likely to be needed (whether for heterologous boosting or to address supply challenges, cost of goods, mutations, sub populations, duration, reinfection etc.)

"If disease transmission rates are low, the only way that next the wave of vaccines could be ‘immuno-bridged’ to first generation licensed vaccines quickly will be through human challenge studies. The option for large-scale field efficacy studies simply may not exist.”​

Ultimately, the VTF seeks to put the UK ‘at the forefront of global vaccine research, development, manufacture and distribution’. It says that, in building up clinical studies in these ways, it can build pandemic preparedness for COVID-19 and beyond.