World Health Organization chief scientist Soumya Swaminathan believes there is a leading candidate in the race to develop a COVID-19 vaccine. That leader is AZD1222, the new candidate for the coronavirus vaccine that is being developed by AstraZeneca (NYSE: AZN) and Oxford University.
And the world now knows more about how safe and effective AZD1222 could be. AstraZeneca announced provisional results Monday of an ongoing phase 1/2 clinical study of the experimental vaccine COVID-19. The provisional results were published in The lancet. Here are three key things you will want to know about the AstraZeneca news.
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1. Good news about neutralizing antibodies
Arguably, the most anticipated metric from the AZD1222 phase 1 study was the number of patients who generated neutralizing antibodies. Neutralizing antibodies have the potential to prevent infection with SARS-CoV-2, the new coronavirus that causes COVID-19.
The results published in The lancet indicated that 32 of 35 participants (91%) demonstrated neutralizing antibodies one month after receiving an injection with AZD1222. All 10 patients who received a second dose of the experimental vaccine had neutralizing antibodies.
Oxford University professor Andrew Pollard, who was the study’s lead investigator, stated: “The immune responses observed after vaccination are in line with what we hope will be associated with protection against the SARS-CoV-2 virus. ” He added that the strong immune response seen in participants who received two doses of AZD1222 indicates “that this could be a good strategy for vaccination.”
It is generally difficult to accurately compare the results of clinical trials for one vaccine candidate against another. However, there will surely be some attempts to stack the results for AZD1222 against ModernThe candidate for the COVID-19 mRNA-1273 vaccine. Moderna’s shares soared last week after the results of a phase 1 study of mRNA-1273 were released in The New England Journal of Medicine. Those results showed that neutralizing antibodies were produced in the 45 study participants after the second dose of mRNA-1273.
2. Solid T cell responses
Another thing that researchers especially look for in the results of COVID-19 vaccine candidates is the responses of T cells. T cells are white blood cells that play a key role in the body’s immune response. T cell responses may be important in protecting against SARS-CoV-2 infection.
Although exactly how T cells are involved in fighting the novel coronavirus is still unclear, research suggests the potential of a T cell response as an important factor in reducing the severity of COVID-19. Previous studies have found that some people infected with the new coronavirus who showed no symptoms developed a robust T-cell response despite having no detectable antibody.
So how did AZD1222 fare on this front? Very good. AstraZeneca stated that a T cell response was induced in all participants in the clinical study. Those responses peaked on day 14 after injection, but were sustained for two months. Mene Pangalos, executive vice president of research and development (research and development) at AstraZeneca, said the provisional data “encourages” the company; especially noted the response of T cells.
3. There are no yellow flags related to safety.
Preliminary data on the immune response would not mean much if AZD1222 caused severe adverse effects. However, that was not the case.
There were no yellow flags related to safety in the provisional results. Pollard said in a statement that “Provisional Phase I / II data for our coronavirus vaccine show that the vaccine did not lead to any unexpected reactions and had a similar safety profile to previous vaccines of this type.”
This does not mean that no adverse reactions were observed. AZD1222 reactions in the study included pain and tenderness at the temporary injection site, mild to moderate severity headaches, chills, fatigue, fever, malaise, and muscle pain. However, these reactions were reduced by giving participants acetaminophen. Adverse reactions also occurred less frequently after participants received the second dose of AZD1222.
Whats Next
The phase 1/2 study for which interim results were reported is still ongoing. However, AstraZeneca and the University of Oxford have also initiated phase 2/3 clinical trials for AZD1222 in the UK, Brazil and South Africa. A late-stage study of the COVID-19 vaccine candidate will also begin soon in the U.S.
AstraZeneca is moving forward on the assumption that those late-stage studies will be successful. The company is preparing to supply more than 2 billion doses of AZD1222 to fulfill its agreements with the United Kingdom, the US and various non-profit organizations.
Although the intermediate phase 1/2 results for AZD1222 were positive, AstraZeneca shares fell on Monday after the release of data in The lancet. But the pharmaceutical stock could have a major catalyst when late-stage results are announced in a few months.
