Beijing Biological Products Institute, a division of the China National Biotec Group (CNBG), posted a brief announcement online that its vaccine had a 79.34 per cent efficacy in a phase III study and was safe. The company, part of state-owned Sinopharm - one of the world’s largest vaccine manufacturers—said it is seeking approval from China’s regulatory agency.
While apparently good news, the statement left vaccine scientists clamoring for details. It said nothing about the number of trial participants, the rates of COVID-19 in the vaccinated and placebo groups, or even the locations of the trials. And it came three weeks after the health ministry in the United Arab Emirates (UAE), one country staging efficacy trials of the Sinopharm vaccine, issued a short press release that claimed 86 per cent efficacy.
Then, the United Kingdom authorised emergency use of a vaccine made by AstraZeneca and the University of Oxford that had earlier caused perplexity after researchers reported efficacy results that combined trials with different populations, dosing of shots, and intervals between the prime and booster injections. Still more surprising, the U.K. Medicines and Healthcare products Regulatory Agency (MHRA) said the booster shot could be delayed for up to 12 weeks after the primary shot. It explained that an “exploratory analysis” of some trial participants found that the vaccine efficacy was 73 per cent after one full dose—a figure that, confusingly, was higher than the 62 per cent after two full doses reported earlier in a study published in TheLancet. The delay would make it possible to give more people one shot quickly, a strategy that might bring down severe disease and death more quickly.
But some scientists questioned MHRA’s decision, wondering how much protection a single shot offers. “People are scratching their heads and going, Where are the data?” Moore says. Biostatistician Natalie Dean of the University of Florida thinks the MHRA moved too quickly and without enough explanation of its decision. “Clearly there were deliberations that the U.K. had about this, but we don't have access to those discussions,” says Dean. “I think there's something lost in the process when we don’t have a really transparent approach.”
Still, COVID-19 vaccines are in short supply the world over, and both the Sinopharm report and the MHRA decision are likely to speed up immunizations. The AstraZeneca/Oxford collaboration hopes to make 3 billion doses next year, and Sinopharm has 100 million doses on hand and projects that it will produce 1 billion next year. “The news that the Sinopharm vaccine is effective is of course good news,” says epidemiologist Keiji Fukuda of the University of Hong Kong. “Having more vaccines to choose from is very welcome.”
CNBG has not announced pricing, but in an apparent bid to gain acceptance in developing countries, Chinese authorities have pledged to make vaccines available at “fair and reasonable prices,” possibly by subsidizing purchases. AstraZeneca/Oxford have set up a nonprofit that plans to sell vaccine for as little as $3 per dose. The recently approved vaccines produced by Pfizer/BioNTech and Moderna, by contrast, cost roughly 10 times more, and the companies combined will have around 2 billion doses at most by the end of next year.
Their vaccines, which both rely on messenger RNA coding for a viral surface protein, present another obstacle for many countries: They require transportation at subzero temperatures. In contrast, the AstraZeneca/Oxford vaccine contains a harmless adenovirus engineered to shuttle the DNA for that same viral gene into the body, whereas the Sinopharm vaccine contains a chemically inactivated version of the entire virus. Both only require conventional refrigeration.
Thousands of Chinese citizens—including front-line health care staff, teachers, and public transport workers—already have received a Sinopharm vaccine under an emergency use authorization. Both the UAE and Bahrain have also issued an emergency use authorization for the vaccine. (Science Mag)
