There is an urgent and global wait for an effective COVID-19 vaccine with over 240 currently in development.
In fact, there is much anticipation that a vaccine will offer an exit strategy from the pandemic and the UK government has established a vaccine taskforce to drive forward the development of a vaccine. However, writing in the Lancet, Kate Bingham, the head of this taskforce, has cautioned that we should guard against what she termed “complacency and over-optimism”. She notes that the first vaccine is likely to be imperfect, will not prevent infection and only reduce the symptoms and might not be effective for everyone. Given that COVID-19 preferentially kills patients over the age of 65, any vaccine needs to offer protection in this group and Bingham states that the UK has secured access to at least six vaccines, each with a different format, for example, adenoviral vectors, mRNA, adjuvant proteins and whole inactivated viruses. Furthermore, she emphasises that while the most advanced vaccines from AstraZeneca and the university of Oxford have demonstrated immunogenicity, these are based on novel formats and for which there is little experience as vaccines. In fact, vaccines using the more traditional format, for example, adjuvant proteins and whole inactivated viruses are unlikely to be available until late 2021.
The first Phase III efficacy data from the leading vaccines will be available by the end of 2020, provided that enough patients are recruited and the taskforce is attempting to accelerate recruitment in disease hotspots. The current primary outcome measure for these vaccines is protection against COVID-19 and a reduction in symptom burden. Bingham describes how the taskforce has options to purchase enough doses of each vaccine type to use in adults over the age of 50, health and social care workers and people with underlying comorbidities.
Bingham also makes the rather sobering point that even if an effective vaccine is developed, global manufacturing is currently and quite simply inadequate, to meet the demand for the billions of doses that will be required. She concludes by calling for international collaboration to not just ensure a high degree of readiness to meet the challenges posed by the current pandemic, but to help prepare for any possible future pandemics.
Bingham K. The UK Government’s vaccine taskforce: strategy for protecting the UK and the world. Lancet 2020. https://doi.org/10.1016/ S0140-6736(20)32175-9