A box and a vial of AstraZeneca's COVID-19 vaccine are seen in a general practice facility, as the spread of the coronavirus disease (COVID-19) continues, in Vienna, Austria May 18, 2021. REUTERS/Leonhard Foeger
A Spanish study on mixing COVID-19 vaccines has found that giving a dose of Pfizer’s (PFE.N) drug to people who already received a first shot of AstraZeneca (AZN.L) vaccine is highly safe and effective, preliminary results showed on Tuesday.
The Combivacs study, run by Spain’s state-backed Carlos III Health Institute, found the presence of IgG antibodies in the bloodstream was between 30 and 40 times higher in people who got the follow-up Pfizer shot than in a control group who only received one AstraZeneca dose.
Meanwhile, the presence of neutralising antibodies rose sevenfold after a Pfizer dose, significantly more than the doubling effect observed after a second AstraZeneca shot.
Around 670 volunteers between the ages of 18-59 who had already received a first dose of AstraZeneca’s vaccine participated in the study, with some 450 given a Pfizer dose.
Just 1.7% of the participants reported severe side effects, which were limited to headaches, muscle pain and general malaise, said Dr Magdalena Campins, one of the study’s leaders.
“These are not symptoms that can be considered serious,” she said.
In a U.K. “mix-and-match” study, first findings recently showed that people vaccinated with a shot of Pfizer’s vaccine followed by a dose of AstraZeneca’s, or vice versa, were more likely to report mild or moderate symptoms such as headaches or chills than if they received two of the same type. Data on immune responses are expected in the coming months. read more
Spain embarked on the study to determine how best to proceed after limiting AstraZeneca’s shot to people aged over 60 due to concerns about blood clotting in younger people.
That restriction caused widespread uncertainty and meant some younger people who had already received a first dose have been excluded from getting a second. read more
“Today’s results support the possibility of vaccinating patients who have received the first dose from AstraZeneca, but the decision is not up to the investigators of this study,” said Jesus Antonio Frias, clinical director at Carlos III.
Our Standards: The Thomson Reuters Trust Principles.
Convenience retail is becoming an increasingly data-driven business, with operators balancing tight margins, shifting consumer…
As enterprises have moved more workloads into virtualised environments, the hypervisor has become a critical…
Rally Saudi Arabia will not form part of the 2026 FIA World Rally Championship due…
Outdoor footwear is increasingly expected to do more than perform on a trail. Consumers move…
The non-alcoholic beverage market is beginning to move beyond the simple promise of drinking less.…
For clean-energy technology companies, sustainability reporting is increasingly moving beyond a compliance exercise. Investors, customers…