As the Coronavirus Disease 2019 (COVID-19) has raised global pandemic, becoming one of the most serious public health problems around the world, bringing heavy social and economic burden to all countries and regions, there are urgent needs of effective vaccines to deal with it. Many countries are actively working on the development of effective vaccines to break the disturbing situation.
Heat: over 100 vaccines are under development
Dr. Tedros Adhanom Ghebreyesus, World Health Organization Director-General announced the initiative to launch cooperation in accelerating development, production and fair access to the prevention and control tools of COVID-19 with global partners, which receives unanimous support at the on-line pledging event hosted by the European Commission, with 7.4 billion Euros committed, to promote the research, development, production and the fair distribution of the vaccines.
Process: 8 vaccines in clinical trials
According to the document published on the official website of WHO entitled Draft Landscape of COVID-19 Candidate Vaccines, there are 8 vaccines in the clinical test stage, and 100 pre-clinical staged candidates, which fully reveal the heat of COVID-19 vaccine development, including one adenovirus vector vaccine and three inactivated vaccines from China, Modena's mRNA vaccine, Pfizer's mRNA vaccine, Inovio's DNA vector vaccine from the USA, and one adenovirus vector vaccine from Oxford University.
Focus: S protein on the surface of SARS-CoV-2
The development of mRNA vaccines really stands out. The S-glycoprotein of SARS-CoV-2 binds to ACE2 receptor through its receptor binding domain (RBD), enabling the virus to fuse with the cell membrane and enter the host cell. Multiple studies have revealed that the S protein is a crucial target antigen for the development of mRNA vaccine of SARS-CoV-2. There are two main schemes: S protein based vaccine and virus like particle (VLP) based vaccine. The first type adopts mRNA to express RBD (S-RBD) on the surface of S protein or S protein of SARS-CoV-2, to induce neutralizing antibodies in vivo. The second scheme utilizes mRNA to generate empty virus particles with the same shape as the new coronavirus, namely VLPs that share similar structure with the real virus. VLP triggers the human immune system to produce protective antibodies, but is non infections because it does not contain genetic substances.
Optimistic time of approval: September 2020
During clinical trials, most of the teams choose to start from small-scale trials, except for Jenner Institute of the Oxford University that had already verified the safety of their adenovirus vector vaccine in vaccination trials. The scale of their first phase clinical trial reached 1100 people. In May, the second phase and the third phase of the combined trial started, involving 5000 people, meanwhile testing the effectiveness and safety. Pfizer and BioNTech (a German pharmaceutical company) announced that their new coronavirus vaccine would be ready for emergency use in the United States as early as September 2020 if it passed the tests starting from May 4th.
There are still steps away from success. With regard to the 100 pre-clinical candidates, competent biotechnology CROs, such as Creative Biolabs (established in 2004, a solution provider in the field of vaccine design) can help with accelerating preclinical assessment procedures through processing in vivo assays and in vitro assays, and thereby checking the inherent toxicity, toxicity associated with the pharmacodynamic activity, toxicity associated with the pharmacodynamic activity, and more importantly, the potency.