São Paulo Government Claims Coronavac Achieved 78% Efficacy in Brazilian Trials

RIO DE JANEIRO, BRAZIL – Studies have shown that the Butantan vaccine is 100% effective for severe and moderate cases, but pressure is growing for details to be disclosed. Emergency use should be officially requested by Friday, January 8th.

The Coronavac, a vaccine developed by the Chinese Sinovac laboratory together with the Butantan Institute, showed 78% efficacy against Covid-19 in the trial developed in Brazil and sponsored by the Government of São Paulo, according to the state health authorities.

The immunizer, at the center of a political feud between President Jair Bolsonaro and Governor João Doria, also ensured total protection against deaths in vaccinated volunteers who contracted the disease.

The data were passed on by the state administration, which disclosed the percentages albeit with no further details on the numerical research figures. A report should only be submitted following the emergency use application at ANVISA, which was started on Thursday and should be formally submitted by Friday – throughout the day, pressure for the disclosure of complete data increased.

The São Paulo government hopes to begin vaccinating priority groups – which include the elderly, healthcare professionals, indigenous and quilombola communities – on January 25th. Doria’s estimate is to have vaccinated nine million people by March.

Since July, 12,476 front-line healthcare professionals, more susceptible to contracting the infection, have participated in trials. The study was conducted with 16 clinical centers in eight Brazilian states and monitored by international health organizations.

Butantan president Dimas Covas explained that hospitalization, severe and mild cases were prevented in 100% of immunized patients. And that 78% of the immunized patients did not need outpatient care, when the individual presents a significant symptom that requires medical assistance.

“We are preventing severe, moderate cases and reducing the milder symptoms. So it is an excellent vaccine so far. We need it to reach people as soon as possible”, he says.

ANVISA procedure to request emergency use, according to the Butantan president, includes an initial meeting that was held on Tuesday morning, when representatives of the two agencies met to submit the Brazilian trial. A new meeting to enlighten the agency was scheduled for the end of the day, and the Butantan hopes to officially apply for emergency use by Friday.

Only after this official formalization should the trial report be released, with more specific data about the groups. For now, Dimas Covas said that half of volunteers were administered the vaccine and the other half a placebo, and that there was no difference in efficacy observed between young and elderly volunteers. “There are no observed differences at this time,” he points out.

As the elderly are known to have a different immunology from the younger groups, the institute is monitoring trials with elderly volunteers to analyze whether a third dose is required and what interval between doses is most appropriate for this population.

The São Paulo government hopes to obtain endorsement by the agency to begin emergency vaccination on January 25th. The state strategy includes converting other spaces – such as schools, train stations, pharmacies – and also implementing drive thru in vaccination posts.

The goal is to vaccinate nine million people in three months. To complete the full first phase, 18 million doses are required. The Government also says it has already purchased syringes and estimates that 27 million of them will be needed in this phase. So far, approximately 10.8 million doses of the Coronavac have reached the country.

But the unfolding of the national vaccination plan is weighing on the state planning. Under pressure from governors and amid the political conflict between Doria and Bolsonaro, the federal government is now racing against time to start immunization before São Paulo. One day before the announcement of data on the Coronavac, Minister of Health Eduardo Pazuello went on television to pledge the start of immunization in January.

He announced a projected 354 million doses for 2021, counting on 100 million Coronavac doses through a memorandum of understanding signed with the Butantan Institute. Pazuello failed to detail when the vaccines would be available, but in recent days he has negotiated the purchase of two million doses from AstraZeneca to advance vaccination.

The Minister also announced a Provisional Measure signed by the President to guarantee the purchase of vaccines even before receiving ANVISA approval, an argument reiterated by the federal health authorities to justify the delay in negotiations.

In parallel, the Butantan Institute is negotiating future exports of its Coronavac. Dimas Covas states that at least six countries have already started discussions in this direction, such as Argentina, Peru, Bolivia, Uruguay, Honduras and Ecuador. “These negotiations depend on the contract to determine the supply date. At this time, we have not finalized any contract yet,” he said.