Pfizer vs AztraZeneca vaccine study
This study was conducted in one part because of the idea of extending the window for a 2nd dose of the Pfizer vaccine so that a greater population can receive at least one dose of (any) vaccine.
Their findings:
- one dose of Pfizer and one dose of AztraZeneca provided similar antibody response.
- however, cellular response is pretty weak with both vaccines. AZ vaccine still provided a 3x greater T cell response than Pfizer.
- vaccine helps even in previously infected people
- 5 weeks between first and second Pfizer dose is fine
Pretty consistent with what previous studies have shown and what we’ve been hearing with need for boosters. Antibodies will wane over time. Ability for body to illicit various T cell responses is low, especially with Pfizer.