AstraZeneca (NASDAQ:AZN) announced today that its potential COVID-19 vaccine prompts an immune response in older and younger adults.
The vaccine candidate is currently in a Phase 3 trial.
In September, the company had put its vaccine trial on hold after a U.K. participant suffered neurological symptoms. But the AZD1222 vaccine candidate appears to be safe based on interim results of the late-stage study. Adverse events related to the vaccine have been lower in older than younger adults. Conversely, the immune response from the two age groups was similar.
AstraZeneca announced on Friday that FDA and other regulators granted permission for the trial to continue.
Other COVID-19 vaccines in Phase 3 trials have also prompted immune responses in older patients.
The vaccine, which AstraZeneca is developing in collaboration with the University of Oxford, is unique in its use of a replication-deficient chimpanzee viral vector. Janssen’s uses a non-replicating human adenovirus as a vector.
Vector-based vaccines can prompt fevers and headaches, according to an article in The Scientist. But vector-based vaccines can prompt immunogenicity without the use of adjuvant, a pharmacological or immunological agent intended to optimize the immune response.
Conversely, Moderna’s and Pfizer’s vaccine platforms use mRNA encapsulated in a lipid nanoparticle.