New UK challenge trial studies if people can catch coronavirus again

Ruben Hill
April 19, 2021

A team of researchers at the University of Oxford has announced the launch of a human challenge trial under which people who have fought off the Covid-19 will be re-exposed to it in order to develop more effective vaccines against the virus.

The earliest volunteers in the world's first human challenge trial involving the coronavirus, conducted by Imperial College in London, left quarantine in late March.

They will be re-exposed to the virus in a safe and controlled environment while a team of researchers monitor their health.

Researchers are looking for 64 healthy, previously Covid-infected volunteers from 18 to 30 years old to be studied under controlled, quarantined conditions for at least 17 days, the United Kingdom university said Monday.

The Oxford study "has the potential to transform our understanding by providing high-quality data on how our immune system responds to a second infection", said Shobana Balasingam, a research adviser at the Wellcome Trust, which is providing funds.

"When we re-infect these participants, we will know exactly how their immune system has reacted to the first COVID infection, exactly when the second infection occurs, and exactly how much virus they got", McShane said.

She added that the work would help understanding of what immune responses protect against reinfection.

The study will take phase in two phases.

In the United Kingdom, similar research involving 90 people of the same age group is ongoing at the moment, in which volunteers are infected with the coronavirus in order to test vaccines and treatments on them.

The study was divided into two phases; the first establishing the lowest dose of virus to initiate virus replication, but only result in "little or no symptoms" in up to 64 healthy adults aged 18 to 30 who have fully recovered from a previous coronavirus infection. Once the dosing amount is established, it will be used to infect participants in the second phase of the study, which is expected to start in the summer. According to Helen McShane, chief investigator of the study and professor of vaccinology at the Department of Paediatrics, University of Oxford, "First, we will define very carefully the baseline immune response in the volunteers, before we infect them". The virus used in the study will be the original strain that emerged from Wuhan, China, and participants will be quarantined in a specially designed hospital suite for a minimum of 17 days following infection, the statement said.

Participants who develop Covid symptoms will be treated with an antibody drug from Regeneron Pharmaceuticals Inc that's been authorized by USA regulators, Oxford said. The trial participants will only be discharged if they are no longer infected and at risk of spreading the disease.

McShane stated that those who participate would be compensated for their contributions, which would be just under £5,000 per person.

Other reports by Click Lancashire

Discuss This Article