The media is awash with reports on Covid-19 vaccines from Russia, China, Pfizer, AstraZeneca and countries like the United Kingdom and United States ordering millions and vaccinating their citizens. It is a multibillion dollar vaccine race. But one story that stood out was Australia’s failed Covid-19 vaccine.
The vaccine was being trialed by University of Queensland and CSL and was stopped because participants received “false positive” results on HIV tests. They were not infected with HIV! I repeat they were not infected with HIV.
To make the vaccine, the researchers used small chemical parts of HIV to make the vaccine more stable. These chemical parts or proteins caused participants to produce HIV antibodies that were picked up in a range of HIV tests. In other words, if the vaccine had been widely rolled out, this could lead many people to think they had HIV when they didn’t.
The news prompted the Australian government to announce it had cancelled its agreement to order 51 million doses of the UQ/CSL vaccine, which was always contingent on successfully completing clinical trials.
Instead, the government will supply more doses of other vaccines, including 20 million extra doses of the University of Oxford/AstraZeneca vaccine, to be made by CSL. The Oxford/AstraZeneca Covid-19 vaccine is the first with published peer-reviewed results from phase 3 clinical trials, a significant milestone.
The chemical parts of HIV that they used for the UQ/CSL Covid-19 vaccine are harmless and do not cause HIV. However what happens when you inject some with this vaccine, people’s immune systems recognise it as “foreign” and raise antibodies against it. Until now, the research team thought the chance of that happening was low.
CSL said people in the 216-person trial were fully informed of this possibility. However these “false positive” HIV tests mean unnecessary anxiety while people sought further clarification about their HIV status. Routine follow-up tests confirmed there was no HIV present in trial participants.
The researchers and the Australian government communicated these findings to prevent undermining the public’s confidence in the Covid-19 vaccination programme. For vaccine programs to be effective, you have to have the public on board. So by acting early to clearly communicate concerns, the researchers have acted appropriately.