IBOV 172,060.43 ▲ 0.42% IPC MEX 72,006.05 ▲ 0.16% MERVAL 2,848,945 — — USD/BRL5.60▲ 0.24% USD/MXN18.64▲ 0.20% USD/CLP985.84▲ 0.31% USD/COP3,279▼ 0.87% USD/PEN3.41▼ 0.02% USD/ARS1,544▼ 0.03% USD/UYU40.52▲ 3.32% USD/PYG6,174▲ 3.14% USD/BOB11.63▲ 1.12% USD/DOP60.48▲ 0.05% USD/CRC446.01▲ 1.79% USD/GTQ7.64▲ 3.18% USD/HNL26.90▲ 3.29% USD/NIO36.62▲ 2.73% USD/VES902.19▼ 0.13% USD/PAB1.00— 0.00% USD/BZD2.00— 0.00% USD/JMD157.49▲ 2.33% USD/TTD6.72▲ 2.22% EUR/BRL6.20▼ 0.49% BRENT 92.41 ▼ 0.38% WTI 86.11 ▼ 0.49% IRON ORE 161.91 — — COPPER 6.21 ▼ 1.11% GOLD 3,953 ▼ 1.19% SILVER 51.06 ▼ 1.58% SOY 1,229 — 0.00% CORN 448.00 — 0.00% WHEAT 597.25 ▼ 0.38% COFFEE 268.95 ▼ 0.02% SUGAR 18.02 ▼ 2.49% ORANGE JUICE 146.60 ▼ 0.10% COTTON 82.88 ▲ 5.55% COCOA 5,032 ▲ 2.55% BEEF 218.98 ▼ 0.10% CATTLE 332.63 ▲ 0.69% LITHIUM 61.07 ▲ 1.82% PETR4 43.55 ▼ 3.11% VALE3 64.43 ▼ 0.57% ITUB4 41.72 ▲ 1.26% BBDC4 14.33 ▼ 1.44% ABEV3 15.85 ▲ 0.38% BBAS3 16.89 ▼ 1.23% B3SA3 14.80 ▲ 2.21% WEGE3 51.61 ▲ 1.30% PRIO3 61.47 ▲ 2.42% SUZB3 53.80 ▼ 1.21% RENT3 30.24 ▲ 1.51% AZZA3 15.37 ▲ 4.34% CSAN3 3.03 ▲ 13.06% RAIZ4 0.30 ▼ 98.60% PCAR3 2.54 ▼ 0.78% GMAT3 4.08 ▲ 7.09% PSSA3 45.98 ▼ 1.48% CVCB3 0.86 — 0.00% POSI3 3.32 ▲ 5.40% SLCE3 17.05 ▼ 0.23% NATU3 5.62 ▲ 1.26% BRKM5 2.92 — 0.00% RANI3 8.39 ▼ 0.71% CSNA3 4.52 ▲ 3.20% IBOV 172,060.43 ▲ 0.42% IPC MEX 72,006.05 ▲ 0.16% MERVAL 2,848,945 — — USD/BRL 5.59 ▲ 0.07% USD/MXN 18.60 ▲ 0.02% USD/CLP 984.41 ▲ 0.16% USD/COP 3,279 ▼ 0.87% USD/PEN 3.41 ▼ 0.02% USD/ARS 1,544 ▼ 0.03% USD/UYU 40.52 ▲ 3.32% USD/PYG 6,174 ▲ 3.14% USD/BOB 11.63 ▲ 1.12% USD/DOP 60.48 ▲ 0.05% USD/CRC 446.01 ▲ 1.79% USD/GTQ 7.64 ▲ 3.16% USD/HNL 26.90 ▲ 3.29% USD/NIO 36.62 ▲ 2.73% USD/VES 902.19 ▼ 0.13% USD/PAB 1.00 — 0.00% USD/BZD 2.00 — 0.00% USD/JMD 157.49 ▲ 2.41% USD/TTD 6.72 ▲ 2.22% EUR/BRL 6.19 ▼ 0.58% BRENT 92.41 ▼ 0.38% WTI 86.11 ▼ 0.49% IRON ORE 161.91 — — COPPER 6.21 ▼ 1.11% GOLD 3,953 ▼ 1.19% SILVER 51.06 ▼ 1.58% SOY 1,229 — 0.00% CORN 448.00 — 0.00% WHEAT 597.25 ▼ 0.38% COFFEE 268.95 ▼ 0.02% SUGAR 18.02 ▼ 2.49% ORANGE JUICE 146.60 ▼ 0.10% COTTON 82.88 ▲ 5.55% COCOA 5,032 ▲ 2.55% BEEF 218.98 ▼ 0.10% CATTLE 332.63 ▲ 0.69% LITHIUM 61.07 ▲ 1.82% PETR4 43.55 ▼ 3.11% VALE3 64.43 ▼ 0.57% ITUB4 41.72 ▲ 1.26% BBDC4 14.33 ▼ 1.44% ABEV3 15.85 ▲ 0.38% BBAS3 16.89 ▼ 1.23% B3SA3 14.80 ▲ 2.21% WEGE3 51.61 ▲ 1.30% PRIO3 61.47 ▲ 2.42% SUZB3 53.80 ▼ 1.21% RENT3 30.24 ▲ 1.51% AZZA3 15.37 ▲ 4.34% CSAN3 3.03 ▲ 13.06% RAIZ4 0.30 ▼ 98.60% PCAR3 2.54 ▼ 0.78% GMAT3 4.08 ▲ 7.09% PSSA3 45.98 ▼ 1.48% CVCB3 0.86 — 0.00% POSI3 3.32 ▲ 5.40% SLCE3 17.05 ▼ 0.23% NATU3 5.62 ▲ 1.26% BRKM5 2.92 — 0.00% RANI3 8.39 ▼ 0.71% CSNA3 4.52 ▲ 3.20%
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Thursday, November 12, 2026

Covid-19 Brazil

Covid-19 Vaccine Trial Successful; Pfizer Could Produce One Billion Doses in 2021

By · · 2 min read

RIO DE JANEIRO, BRAZIL – July began with good news as the experimental vaccine against the novel coronavirus produced by pharmaceutical giant Pfizer in partnership with biotechnology company BioNTech has yielded positive results in limited human trials. The vaccine has encouraged an immune response in healthy patients but has also caused side effects such as fever when administered in higher doses.

The highest dose of 100 micrograms caused fever in half of the trial subjects - as a result of the side effects, the group was not administered a second dose.
The highest dose of 100 micrograms caused fever in half of the trial subjects – as a result of the side effects, the group was not administered a second dose.
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The study was randomized and tested on 45 volunteers who were administered three doses of the vaccine or a placebo; of these, 12 were given a ten microgram dose, 12 received 30 micrograms, 12 received a 100 microgram dose, and nine were administered a placebo version of the vaccine.

The highest dose of 100 micrograms caused fever in half of the trial subjects – as a result of the side effect, the group was not administered a second dose.

After the second dose of the vaccine was administered, three weeks after the first dose, 8.3 percent of the subjects in the ten microgram group and 75 percent in the 30 microgram group also developed a fever.

Sleep disorders were another reported symptom. However, the researchers did not consider the side effects to be serious and they did not lead to hospitalizations.

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The vaccine was effective in generating antibodies against Covid-19 and some of them neutralized the virus, which could mean that it is able to stop the virus from acting, but whether this higher level of antibodies is effectively able to produce immunity to the disease is not yet known.

Pfizer will conduct further trials soon to establish whether those who were administered the vaccine are 50 percent less vulnerable to the virus.

The news was posted on the Medrxiv website, a leading distributor of scientific breakthroughs that have not yet been peer reviewed. The results are still to be published in a scientific journal.

The companies have not disclosed the differences in the vaccine’s effects by gender, ethnicity or age group. The next trial stages will also focus on the United States. Provided everything goes well, the company expects to produce up to 100 million doses of the vaccine by the end of this year and another 1.2 billion by the end of 2021.

With the positive results, Pfizer saw its shares rise over four percent in the US stock market.

Source: Exame

This article was produced by The Rio Times’ automated AI newsroom. Editorial responsibility: Matthias Camenzind, Publisher and Editor-in-Chief. The Rio Times also runs Ask Rio Times, which answers from 100,000+ of our own articles, the daily Latin America Power Map, and prediction-market odds on elections and markets.. How we use AI · Report an error

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