Beijing Institute comes up with the first vaccine.
First human trial COVID-19 vaccine finds it healthy, induces immune response
The scientists, however, including those from China’s Beijing Institute of Biotechnology said more work is required to confirm the same.
A recent study published in The Lancet journal says that the first COVID-19 vaccine to enter phase I clinical trial is effective, well-tolerated and capable of producing an immune response against the novel coronavirus in humans.
The vaccine developed neutralizing antibodies, and a response mediated by the T-cells of the immune system against the novel coronavirus, SARS-CoV-2, according to the study of 108 adults.
Nonetheless, the scientists, including those from China’s Beijing Institute of Biotechnology, said more work is required to confirm whether the vaccine protects against SARS-CoV-2.
The vaccine showed encouraging results after 28 days in the trial, administered in 108 healthy adults, with the final results to be tested within six months, the study said.
“These findings represent an significant landmark. The trial shows that a single dose of the new type 5 adenovirus vector COVID-19 (Ad5-nCoV) vaccine will develop virus-specific antibodies and T cells within 14 days,” said the Beijing Institute of Biotechnology co-author of the report, Wei Chen.
Based on the findings, Chen said the vaccine may be a possible candidate for further testing.
The researchers however cautioned that the results should be carefully interpreted.
“The complexities of creating a COVID-19 vaccine are immense, and the potential to cause such immune responses does not automatically mean that the vaccine can protect humans against COVID-19,” Chen explained.
The Ad5 vector COVID-19 vaccine used in the trial is the first to be tested in humans, scientists said. It uses a weakened common cold-causing adenovirus — which easily infects human cells, but is unable to trigger disease — to deliver genetic material to the cells that codes for the SARS-CoV-2 spike protein, the study noted.
Such cells then generate the spike protein, the scientists said, and proceed to the lymph nodes where the immune system produces the antibodies.
The researchers clarified that they then identify the spike protein and battle off the coronavirus.
In the trial they tested the safety and capacity of the new Ad5-nCoV vaccine in 108 healthy adults between the ages of 18 and 60 to produce an immune response of various dosages.
The volunteers were allocated either to receive a single injection of the new vaccine Ad5 at a low dose, medium dose, or high dose, they said.
Blood of the volunteers was tested at regular intervals after vaccination to see if the vaccine activated two parts of the immune system, according to the report.
They are the ‘humoral response’ of the body, which is the portion of the immune system that generates infection-fighting antibodies, and the “cell-mediated” arm that depends on a group of T cells to battle the virus, scientists said.
Based on the findings, the researchers said the vaccine was well tolerated by volunteers within 28 days of vaccination at all doses with no reported significant adverse effects.
They said most adverse reactions were mild or moderate, with 83% of those receiving low and medium vaccine doses and 75% recording at least one adverse reaction within 7 days of vaccination in the high dose community.
Such reactions were mild pain registered in over half of vaccine recipients at the injection site, fever in 50% of them as well as weakness, headache and muscle pain.
The study noted within two weeks of vaccination that all of the vaccine’s dose levels caused some form of immune response.
Some of the participants had also exhibited a form of neutralizing antibodies against SARS-CoV-2, the researchers said.
After 28 days, most participants said they experienced a four-fold increase in binding antibodies.
The scientists also noted that 50 % of participants in low- and medium-dose groups and 3/4 of those in the high-dose community showed neutralizing antibodies to SARS-CoV-2.
They said the vaccine has also stimulated a rapid response of T cells in most volunteers.
The researchers said the majority of recipients either displayed a positive T-cell response or had detectable antibodies neutralizing against SARS-CoV-2 up to 28 days after vaccination.
Nonetheless, they said high pre-existing immunity to type 5 adenovirus — the common cold virus vector used in the study could have decreased the participants’ response to both the antibody and the T-cell.
“Our study found that pre-existing Ad5 immunity could slow down the rapid immune response to SARS-CoV-2 and also lower the response rate,” said Feng-Cai Zhu from China’s Jiangsu Provincial Center for Disease Control and Prevention.
Citing the trial ‘s key drawbacks, the authors said the analysis had a limited sample size and was performed with a lack of randomized control group in a fairly short time.
Further research would be required to confirm the same.
Beijing Institute comes up with the first vaccine