Traditional vaccine development and approval take approximately 10-15 years. While the development of the SARS-CoV-2 vaccine met an unprecedented pace, modifying the traditional vaccine development process is not unusual. Throughout history, other viral epidemics have demanded unique approaches to vaccine development and flexibility in approval timelines.
Download this poster from Drug Discovery News to learn about traditional vaccine development and discover how epidemic-level infectious diseases have modified the vaccine development landscape.
Increased globalization facilitates rapid dispersal of infectious diseases. In less than six months, SARS-CoV-2 spread across the world.1
Vaccines are humanity’s best defense against pathogens, but traditional vaccine development takes 10 – 15 years.2
Each emerging infectious disease presents a unique challenge due to distinct epidemiology and mechanisms of transmission. Vaccine development for infectious diseases requires shorter production times and flexibility to account for evolving knowledge about emerging disease pathogenesis.3
The 2014 Ebola virus epidemic changed the paradigm of vaccine production.3 The World Health Organization urged acceleration of the vaccine development pipeline. Today, non-replicating adenovirus vaccines (Ad26 and chAd3) and live-attenuated measles-based or vesicular stomatitis virus-based vaccines (MVA or VSV) are available for Ebola.1
The emergence of SARS-CoV-2 in 2019 led to a monumental acceleration of the vaccine development pipeline. In less than 300 days, scientists began vaccine efficacy trials. SARS-CoV-2 spurred the development and approval of the first mRNA-based vaccine. Similar to vaccines for other infectious diseases, non-replicating adenovirusbased vaccines have also been approved.1
Although not a new pathogen, the Zika virus stirred a lot of attention in 2014 as it made its way into the Western Hemisphere.3 There are no approved vaccines for the Zika virus. Vaccines using a whole inactivated virus or a non-replicating adenovirus are in development.1
MERS-CoV emerged in 2012 as a genetically novel coronavirus.3 A non-replicating adenovirus vaccine and a live-attenuated measles-based vaccine are in development for MERS-CoV. Scientists are also exploring experimental vaccines that use a molecular clamp protein to maintain protein shape and prevent infection.1
Emerging infectious diseases require accelerated vaccine production timelines.3
• Overlapping clinical phases
• Production prior to large-scale safety and immunogenicity assays
• Rolling FDA/EMA review
Computational modeling helps scientists pick the optimal virus region to target and design a vaccine strategy. Scientists use the genetic sequence and other known information about pathogens to predict antigen processing and immune response.
Cell lines are critical to vaccine development. Scientists often use Vero cell lines or historical mammalian cell lines, such as HEK-293 and PER.C6, to grow and test viral vectors for vaccines. Historical mammalian cell lines are also used as a closer approximation of human physiology.5,6
Bioreactors provide a controlled environment to conveniently scale up cell growth. Using bioreactors, scientists maximize vaccine production to meet the demand needed to inoculate large populations.6
1. Excler, J-L. et al. Vaccine development for emerging infectious diseases. Nature Medicine 27, 591-600 (2021).
2. Krammer F. SARS-CoV-2 vaccines in development. Nature 586, 516-527 (2020).
3. Maslow, J. N. Vaccine development for emerging virulent infectious diseases. Vaccine 35, 5437-5443 (2017).
4. Sunita et al. Computational tools for modern vaccine development. Human Vaccines & Immunotherapeutics 16(3), 723-735 (2020).
5. North Dakota Health. COVID-19 Vaccines & Fetal Cell Lines. North Dakota Government https://www.health.nd.gov/sites/www/files/documents/COVID%20Vaccine%20Page/COVID-19_Vaccine_Fetal_Cell_Handout.pdf
6. Berrie, D.M. Development of a high-yield live-virus vaccine production platform using a novel fixed-bed bioreactor. Vaccine 38(20), 3639-3645 (2020).