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Covid-19 Vaccine Development Update

There are 2 front runner vaccines being tested in the US - Moderna is a US Company based in Cambridge Mass and Oxford AstraZeneca is based in the UK, but has US financial support.  Both companies finally published their Phase 1 clinical trial results in the last week in peer-reviewed leading medical journals, and both are ready for Phase 3 "huge trials"  which will continue to test safety and will actually test effectiveness in preventing transmission of SARS-CoV-2 to vaccinated subjects.  These trials are prospective, randomized, placebo-controlled trials in not less than 30,000 volunteers per vaccine.  The trials will be "blinded" so neither the volunteers nor the MDs, Nurses, Trial Coordinators etc. will know what injection the volunteers receive.  The Phase 1 trials for both vaccines demonstrated antibody production, especially neutralizing antibodies which block virus replication.  And side effects were like the usual flu shot - mostly related to the injection site and some flu-like symptoms. 

The collage for my pandemic science series today is to celebrate the beginning of Phase 3 trials.  There are more than 140 vaccines being developed, that have not yet begun clinical trials.  As of today 19 vaccines are in Phase 1 and 13 in Phase 2.  Moderna will begin their Phase 3 trial on July 27th.  If you know the 3 phases of clinical trials, you are now better able to read and listen to the continual "chatter" about vaccines.  We aren't there yet!!  And may not be there until 2021.  But until then we will have to learn to live with the virus - and increasing deaths.  Stay home and stay healthy.

Continue reading below the collage: 



The Moderna-NIH Vaccine Research Center vaccine was made with the newest technology.  Instead of using the viruses themselves (usually dead or made ineffective), they made messenger RNA (mRNA) from the virus binding region of the spike protein of SARS-CoV-2 using the structure reported from China on January 10th. Most vaccines were created by making huge amounts of the antigenic proteins and injected them into us to stimulate the immune response.  Now the mRNA is stabilized and used as the ANTIGEN to stimulate our cells to begin the ANTIBODY immune response. 

The mRNA is transported into cells and acts as a blueprint for the cells to make the important part of the spike protein - the part that attaches to our cells and lets the virus in!  The spike protein then stimulates the immune response in the cells in our body and we make protective antibodies! This method cuts years out of the vaccine development process and has been tested in cell cultures, and various animal models- demonstrating that the immune response is able to then prevent the virus from replication in cells in our body.  Both vaccines completed Phase 2 Clinical Trials in hundreds of volunteers. 

This is complicated but very interesting and hopefully we will all get vaccinated, develop "herd immunity," and stop the pandemic.  The Oxford vaccine is using a similar, but not identical process. 


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