Coronavirus: Aussie vaccine proves effective in animal trials

Australia’s promising coronavirus vaccine has proved effective in easing the symptoms of COVID-19 in advanced animal studies, its makers say.

University of Queensland’s Trent Munro and Keith Chappell.

Australia’s promising coronavirus vaccine has proved effective in easing the symptoms of COVID-19 in advanced animal studies, its makers say.

Tests on laboratory animals showed the University of Queensland jab delivered better immunity levels than those of a person who had the virus and recovered.

After two doses, infected hamsters received the added benefit of a “marked reduction” in the severity of inflammation in their lungs and upper respiratory tract.

“The results we have obtained so far look like two doses do a ­really good job of protecting both against virus replication and the disease,” UQ scientist Keith Chappell said.

The encouraging findings were released overnight at an inter­national scientific forum where leading vaccine developers swapped notes on their progress.

UQ’s molecular clamp immuniser is now in phase-1 human trials to prove it is safe to give to people and can generate a baseline immune response.

The lead-up tests in hamsters — judged a better fit than other animal models, including primates — demonstrated that the UQ vaccine engaged both arms of the immune system, stimulating responses from antibodies and T-cells to the coronavirus.

Dr Chappell said one shot of the formulation eradicated all ­traces of the virus from the lungs of about half the lab animals, while the rest recorded “very reduced levels” of infection. A follow-up dose pushed this even further, attacking viral particles lodged in the throat and sinuses.

“In hamsters, we can confidently say we elicit a stronger neutralising immune response than the average infection in a human being,” Dr Chappell said.

“We believe … all the results to date show that it is safe and likely to provide protection against both the virus infection and the symptoms of the disease.”

The need for an effective vaccine was reinforced when Hong Kong researchers reported on Tuesday that a recovered COVID patient had come down again with the virus, in the first documented case of human reinfection.

This indicated that the disease, which has now killed more than 817,000 people worldwide, including 525 in Australia, could continue to spread among popu­lations that had achieved so-called herd immunity.

UQ project leader Trent Munro said booster shots might be necessary to ensure lasting ­immunity.

Dr Chappell said the goal had to be complete eradication of COVID-19 through social distancing, contact tracing and an ­effective vaccine.

With the first results of an opening human trial expected soon, Dr Chappell said none of the 130 volunteers in Brisbane and Melbourne who received the UQ vaccine had a reaction that gave rise to a safety concern.