Oxford’s Covid-19 vaccine could do more for the world than other vaccines

AstraZeneca has pledged to deliver hundreds of millions of doses to low- and middle-income countries and deliver the vaccine on a non-profit basis to those countries in perpetuity. The vaccine developed at the University of Oxford in England is significantly cheaper than the others and, most importantly, it would be much easier to transport and distribute in developing countries than its rivals because it does not need to be stored at freezing temperatures.

“I think it’s the only vaccine that can be used in these settings right now,” Azra Ghani, president of infectious disease epidemiology at Imperial College London, told CNN.

Technology

“Pfizer and Moderna require freezer storage, which is just not in place in many settings,” Ghani said.

“Cold chain” refrigeration is the standard storage used around the world to deliver vaccines from central sites to local health centers. AstraZeneca’s vaccine is so far “the only one that can be definitively delivered to these systems,” Ghani added.

Vaccines are based on different technologies. AstraZeneca’s offering – like the vaccine from Johnson & Johnson and Russia’s Sputnik V – uses an adenovirus to transport genetic fragments of the coronavirus around the body.

Moderna and Pfizer vaccines use pieces of genetic material called messenger RNA (mRNA) to trick the body to make synthetic pieces of the coronavirus and stimulate an immune response. “This is a relatively new technology and little is known about the stability of mRNA over time,” said Penny Ward, chair of the Education and Standards Committee at the Faculty of Pharmaceutical Medicine. from the UK, to CNN.

She said Moderna and Pfizer accumulating information and manufacturing capabilities, they may be able to find methods of storage at higher temperatures, but the Oxford vaccine “has the potential to be able to be more easily shipped around the world” using the chains. existing supply.

However, it will only be useful if the vaccine’s efficacy levels are maintained during its distribution in developing countries.

Moncef Slaoui, chief advisor to the US government’s Operation Warp Speed, said this week that there were “a number of variables we need to understand” around the differences in dosage and age in the results. from Oxford / AstraZeneca, after which the current US test may need to be changed.

On Thursday, a spokesperson for AstraZeneca told CNN that they are currently in talks with the FDA to include the half-strength dosage regimen in their U.S. trials, which currently have around 10,000 participants.

Ayfer Ali, associate professor of international business at Warwick Business School, said the AstraZeneca vaccine’s “ease of distribution” could “possibly outweigh any potential efficacy.”

“The actual efficacy of mRNA vaccines which are more fragile to transport and store may be lower under real conditions where the correct storage of each dose may be difficult to verify,” she added.

BioNTech said last week it was working with Pfizer to come up with a formulation that would allow its vaccine to be stored at standard temperatures by the second half of 2021. Moderna this month extended its estimate of how long her vaccine could remain stable at refrigerator temperature for about seven to 30 days. This, according to Juan Andres, director of technical operations and quality at Moderna, “would allow for simpler distribution and more flexibility to facilitate larger scale vaccination in the United States and other parts of the world.”

Commit to help

AstraZeneca has pledged 300 million doses of its vaccine to COVAX, a partnership between GAVI, the vaccine alliance; the World Health Organization; and the Coalition for Epidemic Preparedness Innovations (CEPI) to ensure equitable distribution in 92 developing countries. The only other known vaccine developer to commit to a similar scale is Sanofi, at 200 million doses.

A representative from GAVI told CNN that the Serum Institute of India (SII) and the Bill and Melinda Gates Foundation will also provide up to 200 million doses of AstraZeneca and / or Novavax vaccine candidates to low-income countries. Moderna and Pfizer have not promised COVAX any doses.

“[AstraZeneca has] worked with manufacturing experts from this coalition to help find a variety of different manufacturing sites, and of course, it’s not just the vaccine itself, it’s also the glass vials it comes in, the caps that are on the bottles and the syringes and needles, ”Ward said.

“Our vaccine can be rapidly deployed in existing health facilities, which will help stop the spread of this disease while learning more and more about how to prevent and treat it,” said a spokesperson for Oxford University to CNN. He added that a range of vaccines would be needed and some might be more effective for different ages and populations.

“The key to any vaccine is the potential for public health impact, including how quickly it can be distributed. Ours can be quickly and easily distributed around the world, using existing logistics, and easily stored in a refrigerator, ”he said.

Global implications

However, Ghani warned that 20% was “far from the ideal – around 70% – that we would like to see in order to be able to get collective immunity, so some countries will still fall short.”

Duke’s modeling shows that if richer countries bought billions of doses up front to increase their chances of covering their populations, the developing world will be completely dependent on COVAX.

Bill Gates said the solution “doesn’t shame rich countries that are doing the natural thing to want to protect their people” but was to dramatically increase manufacturing capacity.

Stephen Evans, professor of pharmacoepidemiology at the London School of Hygiene & Tropical Medicine, warned that monitoring efficacy and safety issues would be an ongoing challenge in developing countries.

“There may be unwanted effects that would only be apparent in those low and middle income countries; they have different diets, they have different levels of nutrition in general and different characteristics,” he said. at CNN.

While the Oxford vaccine may hold particular promise at this point in helping low-income countries, there are still many caveats about the data that must be resolved before it can be deployed.

Ultimately it will be vital to have as many vaccines as possible, to ensure faster recovery and limit further damage to the world.