Breaking News on COVID-19 Vaccines

On Friday, November 20, 2020, Pfizer and BioNTech submitted a request to the US Food and Drug Administration (FDA) for emergency use authorization for their coronavirus vaccine candidate. This request by Pfizer and BioNTech is the first coronavirus vaccine to seek regulatory clearance from the FDA in the United States.1 "It is with great pride and joy and even a little relief that I can say that our request for emergency use authorization for our Covid-19 vaccine is now in the FDA's hands," Pfizer CEO Albert Bourla said in a video shared on Friday. "This is a historic day, a historic day for science and for all of us. It took just 248 days to get from the day we announced our plans to collaborate with BioNTech to our FDA submission day. 2 The vaccine, known as BNT162b2, could potentially be available for use in high-risk populations in the United States by the middle to end of December, Pfizer and BioNTech said in a statement earlier Friday. The vaccine requires two doses a few weeks apart, and protection is achieved 28 days after the first shot.3 In addition to the Pfizer/BioNTech submission, Moderna is expected to submit their COVID-19 vaccine to the FDA for emergency use authorization (EUA) within the next few days as well. Millions of these vaccines from Pfizer/BioNTech and from Moderna have already been produced through President Trump’s “Operation Warp Speed” so they will be shipped out very quickly to high-risk groups (i.e., hospital patients, the elderly, healthcare workers, first responders, etc.) once they are approved.4 1. Messenger RNA vaccine: Messenger RNA (mRNA) vaccines use newer technology and, if approved, will be the first commercially available vaccine of its type for an infectious disease. For several years, there has been ongoing research using this technology for cancer and also for numerous infectious diseases. It is faster to develop and manufacture in large quantities, which is why this will likely be the first vaccine available. Both the Pfizer/BioNTech and the Moderna products are two step vaccines, meaning people will need to get two shots about 20 days apart. According to researchers it should be safe, easy to make and produce a robust immune response. The human body uses mRNA to tell a specific structure in your cells what kind of proteins to make. This is a lab manufactured mRNA sequence that instructs your cells to make the spike protein found on the outside of the Sars-COV-2 virus. Your body then will learn to recognize this protein (an antigen) and know how to make an antibody for it. The target from the FDA for a vaccine’s effectiveness was 50% with a hope of 60-75% - so the 95% effectiveness reported by Pfizer/BioNTech is really good. This is also a safe vaccine because our body uses this same protein making ability all the time, and in theory should not alter the cell’s DNA in any way. It uses no actual virus, and the mRNA strand degrades quickly and becomes inactive.5 2. Isolated Protein and Adjuvant vaccine: This type of vaccine has been used for other diseases, including some of the flu vaccines. This specific one has two parts. The first is a part of the virus structure and will likely also be the spike protein. This protein is produced from live cells and then isolated. They can be produced from all kinds of cells including eggs, insect cells, etc. The second part is the adjuvant. In a vaccine this is a substance that causes an immune response. Adjuvants can range from things such as Aluminum salts to plant based oils or fats. Aluminum salts (hydroxide or phosphate) are the only adjuvants broadly licensed for inclusion in human vaccines. They have been widely used for 70 years and injected into more than 1 billion people worldwide. 6 3. Viral Vector Vaccine or recombinant viral vectors: This type of vaccine has also been used for other types of diseases. Vaccine companies take a common virus such as a cold virus and make them have the spike protein from the coronavirus on the outside of it. The virus is also typically altered so that it should not be able to replicate itself in an ‘infected’ cell. Your immune system is exposed to the protein of the target virus and acquires the ability to make antibodies to fight the virus.7 4. Live Attenuated Virus or Inactivated Virus vaccine: This type is also used for other types of diseases. The vaccine is made by culturing the actual virus, typically in eggs, and then doing something to it to make it weaker or totally inactivated. The weak or ‘dead’ virus is then put in some type of solution, which may or may not have a preservative, and injected. The body responds to the virus and learns how to fight it off.8 The really good news for everyone is that all four of these types of vaccines are in various stages of development and in clinical trials in a lot of different companies. The need to culture actual viruses and the time it takes to do so is part of the reason why the last three types of vaccines are not going to be available as quickly as the various mRNA versions will be. If “Operation Warp Speed” continues at its current pace, potentially everyone will be able to receive a vaccine by this coming spring. 1 CNN Health https://www.cnn.com/2020/11/20/health/pfizer-vaccine-eua-submission/index.html 2 ‘Ibid ‘CNN’ 3 ‘Ibid ‘CNN’ 4 Health and Human Services https://www.hhs.gov/coronavirus/explaining-operation-warp-speed/index.html 5 RNA vaccines: an introduction https://www.phgfoundation.org/briefing/rna-vaccines 6 Adjuvants and Vaccines https://www.cdc.gov/vaccinesafety/concerns/adjuvants.html 7 Viral Vector Vaccines https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4494222/ 8 Live Attenuated Virus Vaccines https://www.vaccines.gov/basics/types