In the latest global COVID-19 developments, the United Kingdom today announced the launch of the first study to explore giving different COVID-19 vaccines in a two-dose regimen, and a new study added more evidence that the B117 variant is deadlier than the standard version of the virus.
A more agile approach for limited vaccine supply?
The trial of a mixed-vaccine strategy comes as governments look for ways to protect as many people as possible as quickly as possible with vaccines, amid short supply and the threat of more contagious and lethal coronavirus variants.
In a statement, the UK government said it has provided $9.6 million to back a study that will look at the effects of mixing vaccine types for the two doses, such as the one from AstraZeneca-Oxford first, followed by the Pfizer-BioNTech vaccine second.
Jonathan Van-Tam, MBBS, the United Kingdom's deputy chief medical officer and senior officer for the study, said in the statement the goal is to have data to support a more flexible immunization program, if needed, given the challenges of immunizing large numbers of people and the potential for supply bottlenecks.
He also said the study could shed light on whether combining vaccine types could enhance or prolong immune response. "Unless this is evaluated in a clinical trial, we just won't know."
The 13-month study, conducted across eight sites among 800 patients, will also explore the effect of different vaccination intervals on immune response. The study will include eight different arms testing different combinations and timings, including two doses of the same vaccine given either 28 days or 12 weeks apart. Initial findings are expected in the summer.
The control group will include people who receive both doses of the same vaccine. For now, the UK government's timing recommendation remains the same: two doses of the same vaccine, 12 weeks apart.
More findings that B117 is more lethal
Meanwhile, a team from the London School of Hygiene and Tropical Medicine in a preprint study yesterday estimated that the B117 variant is 35% more deadly than the standard virus. Their findings were similar to a Jan 22 report from the UK government, which said that alongside being more transmissible, the variant may be 30% more deadly, based on a preliminary analysis. At the time, officials warned that the findings were based on a limited group and that stronger data were needed.
In the new study, the team analyzed a database of COVID-19 test results and COVID-19 deaths from Sep 1 to Jan 22. They used the S-gene dropout in a positive COVID-19 test as a proxy for the B117 variant.
Their estimate was for males age 55 to 69, 28 days after testing positive.
They didn't identify the mechanism for the increased mortality rate, though they said other evidence suggests variant infections involve higher viral loads.
In other global developments:
- An international survey to gauge trust in COVID-19 vaccines revealed today that confidence has risen, with 54% willing to be vaccinated, up from 40% in November. However, the findings from YouGov and Imperial College of London Institute for Global Health Innovation found wide variations among the 15 countries they covered, with 78% acceptance in the United Kingdom, but 44% in France. Some countries showed lower willingness since the last survey, especially Asian countries such as Japan, South Korea, and Singapore.
- The International Federation of Red Cross and Red Crescent Societies today announced a $110 million plan to help distribute COVID-19 vaccines and warned of potentially devastating consequences if lower income countries don't get timely access to vaccines, according to the New York Times.
- Denmark yesterday signaled that it will introduce a digital "vaccine passport" to help society and businesses reopen and to make travel easier, according to CNN. The country is on lockdown, which is slated to end on Feb 28.
- The global COVID-19 total today rose to 104,694,138 cases, and 2,227,821 people have died from their infections, according to the Johns Hopkins online dashboard.
