Promising vaccine trial pushes into COVID-swamped South Africa, Brazil

Soweto, South Africa — Britain's Prince William went to Oxford University on Wednesday to meet patients taking part in a human trial of a promising coronavirus vaccine. But with cases of COVID-19 plummeting in England, researchers fear the trial involving 10,000 people may not yield results conclusive enough to prove the vaccine works.

They needed to test the drug in a place where more people are being exposed to the deadly virus. So, as the trial continues in England, researchers in South Africa and Brazil — where there are many more people contracting the coronavirus on a daily basis — have launched parallel human trials on the same candidate vaccine.

The Oxford formula is one of about 120 potential vaccines being worked on by teams around the globe. Based on drugs that have proven successful against similar viruses, the Oxford team's vaccine has moved quickly into the large-scale human trial phase. Already there has been huge investment, including from the U.S., to ensure millions of doses can be available as soon as it's proven safe and effective.

Another, even larger human trial of the potential vaccine is set to take place in the U.S. Oxford's pharmaceutical partner AstraZeneca plans to enroll 30,000 people, starting this month, in that trial after receiving $1 billion in investment from the U.S. government. The goal is to make some 300 million doses of the vaccine available in the U.S. before the end of the year — if it works.

For months Oxford's candidate vaccine, technically known as "ChAdOx1 nCoV-19," has been considered one of the world's best hopes for a lasting solution to the COVID-19 pandemic.

CBS News met some of the people volunteering to have the Oxford team's trial vaccine administered at a humble clinic in Soweto, just outside Johannesburg in South Africa.

The first South African volunteers in the Oxford trial waited patiently in the winter sun on Wednesday to receive the experimental vaccine. For the most part, they said they were excited to be part of history.

Khensani Nkuna, 27, said she volunteered, "because it might save lives."

Despite a recent lockdown, and teams of contact tracers working to track down infected patients in South Africa, cases of COVID-19 continue to surge in the country.

Renowned vaccinologist Professor Shabir Madhi, who's leading the trial of 2,000 volunteers, says South Africa is likely still about eight weeks away from seeing infections peak.

"So our ability to be able to determine whether this vaccine protects against COVID-19 or not will probably be much greater than is currently the case in the United Kingdom," he said, adding that his team hopes to see results from the trial before the end of this year.

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The trial in Brazil, which is battling one of the world's most aggressive COIVD-19 epidemics right now, largely mirrors the South Africa experiment, with 2,000 volunteers expected to be administered the candidate vaccine.

Officials at the Federal University of Sao Paulo told the AFP news agency on Wednesday that they'd begun giving the drug to volunteers, focusing on front-line health workers to increase the likelihood of exposure to the coronavirus.

The results of all the trials, in the U.K., South Africa and Brazil and the U.S., can't come soon enough. If the experimental vaccine is proven effective, the Oxford team has already coordinated with manufacturers in several countries to have about 2 billion doses available by early next year.

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