Oxford vaccine may reach 130 million Brazilians in 2021

The vaccine against COVID-19 to be produced by the Oswaldo Cruz Foundation (Fiocruz) in collaboration with pharmaceutical company Astrazeneca and Oxford University is expected to come to another 30 million Brazilians in 2021, raising to 130 million the total number of people reached by the end of next year—when the country should be capable of manufacturing 210 million doses of the vaccine.

The 30 percent expansion is believed to be possible after the result of clinical tests published Monday (Nov. 23) showed that the most efficient vaccination protocol includes a reduced dose of the first application, instead of a full dose.

Astrazeneca and Oxford University announced that the vaccination scheme including a reduced dose and a full dose with a month’s interval had 90 percent efficiency. The protocol with two full doses and the same interval reached 62 percent efficiency. The data surveyed involved 11 thousand volunteers, approximately 2.7 thousand with the more efficient protocol, and nearly 8.9 thousand with the protocol with two full doses.

No serious events were notified in connection with the security of the vaccine, and none of the volunteers vaccinated developed a severe case of COVID-19 or needed to be hospitalized.

Fiocruz’s vice-President for Production and Innovation in Health, Marco Krieger, referred to the announcement as good news, as it confirmed the 90 percent efficiency and brought about an additional gain, since the 210 million doses that Friocruz plans to manufacture next year will reach more people, should the data be confirmed after the study is completed and published.

“Instead of having a vaccine for 100 million Brazilians, we could vaccinate 130 million, which is an extra. Good news, then,” Krieger said in an interview with Agência Brasil.

Production and registration

After a deal was inked with the federal government, vaccine developers initiated the process of technology transfer so that Fiocruz can produce the vaccine in the country. In the first half of the year, the foundation estimates that 100 million doses with an imported active pharmaceutical ingredient (API) will be available, and, in the second half-year, some 110 million doses will be manufactured with an IFA produced at Fiocruz. Krieger explains that the forecast has been kept unchanged, adding that doses are likely to be split.

The whole process pends confirmation and publication of human test results, and the registration of the vaccine with Brazil’s national sanitary regulator Anvisa. In addition to producing the vaccine, Fiocruz is also tasked with lodging the request for registration, which has been done in installments since October through a process known as continuous submission.

In October and November, Anvisa received data including pre-clinical trial results and information on the production and control at industrial plants. Next month, Fiocruz is expected to submit the outcome of clinical tests, which includes the protocol recommended for vaccination.

“As part of the petitioning with the sanitary authorities—in our case Anvisa—it will be stated that the 90 percent efficiency was used with this protocol [with a reduced dose]. This is the protocol to be registered. We must make certain we use the vaccine according to the results of the clinical studies, because it guarantees two things: first, the efficiency, which is fairly high; and second, security,” Krieger said, underscoring how much it depends on the confirmation of results.

Fiocruz is set to lodge the last bundle of documents in January next year, when vaccine production is likely to start, even before Anvisa’s final approval. The vaccine will be produced at the Bio-Manguinhos Industrial Complex, alongside the foundation headquarters, in northern Rio de Janeiro. The goal of bringing production forward is haivng at least 30 million doses by the end of February, when Anvisa’s final report should be ready with the vaccine registration, provided all tests confirm the security and efficiency of the vaccine. If these deadlines are met, Bio-Manguinhos should deliver the first 30 million doses to the Health Ministry in March so they can be made available to the population.

How does the vaccine work?

The vaccine developed by Astrazeneca and Oxford University utilizes viral vector technology, where a genetic sequence of the novel coronavirus is inserted into another virus, incapable of replicating, so that it may be injected into the human body and generate an immunological response.

The vector used is a chimpanzee adenovirus (the cold virus), which carries the coronavirus’s protein S sequence. This is the protein forming the spiky crown it was named after. These spikes are crucial to the invasion of human cells. Clinical tests sought to demonstrate that, once vaccinated, the human body will recognize this protein and may produce defenses that neutralize its action, making it more difficult for a person to fall sick after being in contact with the novel coronavirus.

Thus far, the mutability of the virus is not considered a threat to vaccine efficiency, as the mutations observed show no structural changes in protein S, which indicates that the vaccines targeting this protein may be efficient even after mutations in the new coronavirus.