COVID-19 vaccine update | China’s Sinovac Biotech vaccine is just 50% effective, say Brazil researchers

Last week, the Butantan Institute had said that the efficacy rate of CoronaVac was 78 percent and claimed to supply total protection against severe cases of the disease. Brazil’s Butantan Institute, a São Paulo-based public institute that’s the primary to finish late-stage trials of the CoronaVac vaccine, reported CNBC.

Indonesia starts mass COVID-19 vaccinations with president Joko Widodo

Despite Sinovac’s CoronaVac efficacy rate meeting the 50 percent threshold the planet Health Organization approval for widespread use, Brazilian scientists and health experts have criticised state-run Butantan Institute for a scarcity of transparency in making public its trial data.

The Butantan Institute reportedly delayed releasing trial results 3 times claiming a confidential clause in its contract with Sinovac. On Tuesday, the South American country’s public institute came up with the general efficacy rate of Sinovac Biotech’s CoronaVac, which is nearly half the efficacy rate of competitors like Pfizer-BioNTech and Moderna.

Meanwhile, Sinovac Biotech Ltd on January 13 claimed that the low efficacy rate of fifty .38 percent from its final-stage trial in Brazil is thanks to trial participants, mostly medical workers, who face a high risk of contracting with the coronavirus, reported Bloomberg.

Sinovac Chief military officer Yin Weidong in his defence had said that his competitors — Pfizer Inc. and BioNTech SE — tested their vaccines among volunteers including people from the overall population, who were less exposed to the virus compared to medical workers.

In July 2020, Weidong’s firm had said its phase III clinical trial trial in Brazil would recruit nearly 9,000 health-care professionals. Later, they recruited over 13,000 volunteers and divided them between vaccinated and placebo groups. However, clarity over other participants beyond the initial 9,000 were also medical workers remains to be sceptical.

Brazil, the primary country to finish a late-stage trial of the vaccine CoronaVac, has reported over 8.1 million Covid infections in total and has pinned its hopes on Chinese vaccines as wealthier countries snaffle vaccines developed within the West.

Unlike Pfizer-BioNTech and Moderna, Sinovac Biotech’s CoronaVac is cheaper, easier to move , and may be stored in ordinary refrigerators.

Meanwhile, Brazil’s health regulator Anvisa has stated that it’ll meet on Sunday to make a decision if CoronaVac to be authorised for emergency use or not.

Countries approving/ordering CoronaVac:

Apart from Brazil, Indonesia approved the vaccine for the emergency use of CoronaVac on Monday. Indonesia is that the first country outside China to try to to so after interim data from a late-stage trial showed that CoronaVac was 65.3 percent effective. Last month, Turkish researchers had stated that their interim analysis showed the vaccine to be 91.25 percent effective, on which experts raised their doubts.

The Beijing-based company has recently received new orders from Malaysia and therefore the Philippines. Earlier, Singapore and Hong Kong had placed their order for CoronaVac.