The vaccine COVID-19 AZD1222 showed a strong immune response in all participants in the I / II phase study.
Intermediate data showed strong responses of antibodies and T cells
Intermediate results from an ongoing Phase IV / COV001 study by the University of Oxford showed that AZD1222 was tolerated and generated robust immune responses against SARS-CoV-2 virus in all participants evaluated.
COV001 is a blind, multi center, randomized, controlled phase I / II study in 1,077 healthy adults aged 18 to 55 years. He evaluated a single dose of AZD1222 compared to the Men ACWY pneumococcal conjugate vaccine. Ten participants also received two doses of AZD1222, one month apart.
The results, published in The Lancet, confirmed that a single dose of AZD1222 resulted in a fourfold increase in antibodies to the SARS-CoV-2 virus spike protein in 95% of participants one month after injection. All participants were induced T-cell response, reaching a peak by day 14 and persisting two months after injection.
Neutralizing activity against SARS-CoV-2 (assessed by the MNA80 assay) was observed in 91% of participants one month after vaccination and in 100% of participants who received the second dose. Neutralizing antibody levels seen in participants who received one or two doses were in a range similar to that of convalescent COVID-19 patients. Strong correlations were observed in neutralization assays.
Initial safety responses confirmed that transient local and systemic reactions were common in the AZD1222 group and were comparable to previous trials and other adenoviral vector vaccines. 1-4 These included pain and pain at the temporary injection site, mild to moderate headache, fatigue, chills, fever, malaise, and muscle pain. No serious side effects were reported with AZD1222, and reactions were reduced with prophylactic paracetamol, a pain reliever, and occurred less frequently after the second dose.
Professor Andrew Pollard, lead researcher at the Oxford Vaccine Test at the University of Oxford and co-author of the study, said: “The phase I / II data for our coronavirus vaccine shows that the vaccine did not cause unexpected reactions and had a profile safety similar to previous vaccines. of that type. The immune responses seen after vaccination are in line with what we expect to be associated with protection against the SARS-CoV-2 virus, although we must continue our rigorous clinical trial program to confirm this. “We observed the strongest immune response among participants who received two doses of the vaccine, suggesting that this may be a good vaccination strategy.”
Mene Pangalos, Executive Vice President of R & D BioPharmaceuticals, said: “We are encouraged by intermediate phase I / II data showing that AZD1222 was able to generate a rapid antibody and T cell response to SARS-CoV-2. While there is still work to be done, data today strengthens our confidence that the vaccine will work and allows us to continue our plans for large-scale vaccine production for wide and equitable access worldwide. “
Phase II / III advanced testing is currently underway in the United Kingdom, Brazil, and South Africa and is expected to begin in the United States. The trials will determine how well the vaccine will protect against COVID-19 disease and measure safety and immune responses across different age groups and at different doses.
At the same time, AstraZeneca continues to fulfill its commitment to widespread and equitable access to the vaccine if late-stage clinical trials are successful. To date, commitments for more than two billion doses of vaccine have been agreed with the United Kingdom, the United States, the Alliance for Inclusive Vaccines in Europe, the Epidemic Preparedness Coalition, the Gavi Vaccine Alliance and the Indian Serum Institute.
The announcement today is not expected to affect the Company’s financial benchmarks for 2020, as it is expected that vaccine development costs will be offset by funding from governments and international organizations.