Ad5-nCoV

Ad5-nCoV

Ad5-nCoV, also known as Convidecia, is a COVID-19 vaccine developed by the Chinese company CanSino Biologics in collaboration with the Beijing Institute of Biotechnology. It is a viral vector vaccine that uses a weakened version of a common cold virus (adenovirus type 5) to deliver a piece of the SARS-CoV-2 virus to the body, prompting an immune response.

Development and Approval

The development of Ad5-nCoV began in early 2020, shortly after the genetic sequence of the SARS-CoV-2 virus was published. The vaccine was developed using a recombinant adenovirus type 5 vector, which is a well-established platform for vaccine development. The vaccine was designed to express the spike protein of the SARS-CoV-2 virus, which is the primary target for neutralizing antibodies.

Ad5-nCoV was one of the first COVID-19 vaccines to enter clinical trials. Phase I trials began in March 2020, followed by Phase II trials in April 2020. The results from these trials showed that the vaccine was safe and capable of inducing an immune response. Phase III trials were conducted in several countries, including Pakistan, Russia, Mexico, and Chile.

In February 2021, Ad5-nCoV received emergency use authorization in China, and it has since been approved for use in several other countries. The vaccine is administered as a single dose, which is a significant advantage in terms of logistics and distribution.

Mechanism of Action

Ad5-nCoV uses a non-replicating adenovirus vector to deliver the genetic material encoding the spike protein of the SARS-CoV-2 virus into human cells. Once inside the cells, the genetic material is transcribed and translated into the spike protein, which is then presented on the surface of the cells. This presentation triggers the immune system to recognize the spike protein as foreign and mount an immune response, including the production of neutralizing antibodies and the activation of T-cells.

Efficacy and Safety

Clinical trials have shown that Ad5-nCoV is effective in preventing COVID-19. The vaccine has been reported to have an efficacy rate of approximately 65% in preventing symptomatic COVID-19 infection and 90% in preventing severe disease. The safety profile of the vaccine is similar to other adenovirus vector vaccines, with common side effects including pain at the injection site, fever, fatigue, and headache.

Distribution and Use

Ad5-nCoV has been distributed to several countries, particularly in the developing world, as part of efforts to increase global access to COVID-19 vaccines. The single-dose regimen makes it particularly suitable for use in areas with limited healthcare infrastructure.

Also see

• COVID-19 vaccine
• CanSino Biologics
• Adenovirus vector vaccine
• SARS-CoV-2
• Vaccine efficacy