The vaccine had been in stage one of trials, and proving to be effective in making antibodies.
But it also generated HIV antibodies in some recipients - which meant it showed false positives for HIV.
Australia had previously agreed to buy 51 million doses of the vaccine being developed by Australian firm CSL and the University of Queensland (UQ).
"It was likely to work. But we knew that we didn't want to have any issues with confidence, and this false-positive test may have caused some confusion and lack of confidence"