Oxford and Chinese COVID-19 Vaccines Show Strong Immune Responses in Early Trials
Early clinical trials for COVID-19 vaccine candidates from Oxford University and CanSino Biologics show promising immune responses, producing both antibodies and T cells. Larger-scale studies are now underway to determine if the vaccines actually prevent infection.
A COVID-19 vaccine candidate developed by Oxford University and AstraZeneca proves safe and triggers a strong immune response in early clinical trials involving 1,077 healthy adults. Participants produce both antibodies and T cells after receiving the experimental vaccine, known as ChAdOx1 nCoV-19. Researchers publish these promising findings today in the medical journal The Lancet.
The study reveals that antibody responses peak by day 28 and stay high through day 56, while T cell responses emerge as early as day 7. A small subgroup of 10 participants who receive a second dose shows even stronger antibody production. Although 70% of recipients experience mild side effects like fatigue and headaches, these symptoms are easily treatable with over-the-counter pain medication.
Separate early trial results from CanSino Biologics in China also show strong immune responses, with over 96% of 508 participants developing antibodies and 90% generating T cells. Despite these encouraging signs from both vaccines, researchers caution that it remains too early to confirm if either candidate provides sufficient protection from infection or how long that protection lasts. Larger trials for the Oxford vaccine are currently underway across the UK, US, Brazil, and South Africa.