Category Archives: Tak Berkategori
COVID-19 vaccine development part 18
WHO COVID-19 Solidarity vaccine trial : On 28 May 2020, WHO announced the launch of a coordinated international, concurrent randomized controlled Phase III trial of different vaccine candidates A trial in several sites at once will help speed evaluation and … Continue reading
COVID-19 vaccine development part 17
COVID-19 vaccine candidates in Phase III trials : As of 02 October 2020 there are 42 COVID-19 candidate vaccines in clinical evaluation of which 10 in phase III trials There are another 151 candidate vaccines in preclinical evaluation Phase III … Continue reading
COVID-19 vaccine development part 16
Why there are so many COVID-19 vaccines in development : There are many different COVID-19 vaccines in development because it is not yet known which ones will be effective and safe Based on experience, roughly 7% of vaccines in preclinical … Continue reading
COVID-19 vaccine development part 15
Steps in vaccine development : (Action taken to ensure a new vaccine is safe and works well) Pre-clinical studies Vaccine is tested in animal studies for efficacy and safety, including challenge studies Phase I clinical trial … Continue reading
COVID-19 vaccine development part 14
Nucleic acid vaccines : Instead of a virus, a protein antigen, or a virus expressing the protein, nucleic acid coding for the antigen is injected DNA plasmid: enters nucleus, translated to mRNA for expression of protein Or mRNA can be … Continue reading
COVID-19 vaccine development part 13
Viral vector vaccines : The gene for a pathogen protein is inserted into a different virus that can infect someone without causing disease The safe virus serves as a “platform” or “vector” to deliver the protein that triggers an immune … Continue reading
COVID-19 vaccine development part 12
Protein-based vaccines : A protein is extracted from the virus (alive or inactivated), purified, and injected as a vaccine For coronavirus, this is most commonly the spike protein Virus-like particles work in the same way
COVID-19 vaccine development part 11
VIRUS VACCINES Virus is selected, modified (weakened) or completely inactivated so that it will not cause disease
COVID-19 vaccine development part 10
Immunogens used to develop viral vaccines : Nucleic acids : DNA or RNA coding for a viral protein Strong cellular immunity, rapid development Relatively low antibody response Example of vaccines
COVID-19 vaccine development part 9
Immunogens used to develop viral vaccines : Replicating or non-replicating viral vector : Viral pathogen expressed on a safe virus that doesn’t cause disease Rapid development Prior exposure to vector virus (eg. adenovirus) may reduce immunogenicity Example of vaccines : … Continue reading