The Australian government has scrapped a supply deal with CSL for 51 million doses of its COVID-19 vaccine co-developed with the University of Queensland, after trial participants falsely tested positive for HIV.

The university and CSL said while a phase 1 study evaluating candidate v451 showed it delivered a strong immune response and had a positive safety profile, vaccine trials will not progress to phase 2/3 trials given the possibility of interference with HIV tests.

However, the phase 1 trial, which enrolled 216 Queenslanders and began in July, will continue, and the university said it plans to publish trial results in a peer-reviewed journal.