The University of Oxford and pharmaceutcal giant AstraZeneca have released initial data from trials that show that ChAdOx1 nCoV-2019, their Covid-19 vaccine candidate, is 70.4 percent effective, though it can achieve up to 90 percent protection if a half dose is taken initially, followed by a full dose. The positive results come in the wake of Pfizer and BionTech reporting that their vaccine is 95 percent effective at preventing Covid-19 while Moderna announced that their jab also has 95 percent efficacy. Both vaccines are based on introducing genetic material, mRNA, into the human body in order to produce spike proteins which prevent the coronavirus from entering human cells.
The Oxford University/AstraZeneca vaccine is adenoviral and is based genetically modifying a common cold virus that used to infect chimpanzees. Despite the positive results, there is no data regarding whether the candidates prevent the coronavirus from being transmitted as well as for how long protection lasts. Despite its lower efficacy from a single dose, the Oxford/AstraZeneca vaccine has been shown to work effectively in different age groups, particularly the elderly. It is also significantly cheaper than other Covid-19 vaccines and much easier to store, meaning it can be distributed more easily, potentially making it the shot of choice in poorer parts of the world. The Moderna vaccine can be stored at temperatures of between 2C and 8C for 30 days while the Pfizer/BioNTech vaccine, on the other hand, must be stored at -80C, exacerbating logistical challenges. It usually takes a decade to develop such a vaccine but, astonishingly, the process for creating these candidates has taken a mere 10 months.
It is also important to mention the efforts of other countries, particularly Russia and its Gam-COVID-Vac jab, better known as Sputnik V, which is being developed by the Gamaleya Research Institute of Epidemiology and Microbiology. The Russian Health Ministry announced that Sputnik V is 92 percent effective, though it has proven controversial as it was approved for distribution despite being tested in a small group of people. While experts have urged caution, they have still agreed that the results are encouraging. Elsewhere, China's Sinovac Biotech vaccine has shown promising signs in mid-stage trials, producing an immune response in trials involving 700 people.
Now that several vaccines offer a high level of protection, they need to be approved and distributed, steps that appear imminent. The United States, United Kingdom and Germany have all announced plans to start vaccinations next month while Spain is aiming to vaccinate a quarter of its population within the first three months of 2021. Head of the U.S. Covid-19 vaccine program, Dr. Moncef Slaoui, said that the first Americans could get vaccinated as soon as December 11. Pfizer and BioNtech applied for emergency authorization for the use of their vaccine on Friday and the Food and Drug Administration vaccine advisory committee is set to meet on 10 December and decide whether or not to authorize it.