Vaccine Info

UQ-CSL V451 Vaccine

Last Reviewed
December 15, 2020

University of Queensland (UQ) CSL Vaccine Candidate Description

The University of Queensland (UQ) CSL COVID-19 vaccine candidate (V451) combines the adjuvant technology MF59 to improve immune response, reduce the amount of antigen needed for each vaccine, and enable more doses to be manufactured more rapidly.

The UQ-CSL V451 developed a rapid response “molecular clamp” vaccine platform, a transformative technology patented by UniQuest, UQ’s technology transfer company that enables rapid vaccine design and production against outbreak viral pathogens.

Enveloped viruses have proteins on their surface that drive the virus's fusion and host cell membranes, a key process in infection. These proteins are also the major target of a protective immune response.

Although they can induce an immune response, they are inherently unstable and can change shape when expressed independently. This means that the immune response induced does not efficiently recognize the protein on the virus surface and does not protect subsequent infection.

UQ-CSL V451 has overcome this problem by using its proprietary “molecular clamp” technology that locks the unstable, prefusion version of the surface proteins in a form that allows the immune system to respond more effectively.

This is achieved using their proprietary “molecular clamp” technology that locks these proteins in their native virus surface form. This synthetic protein can then be purified and rapidly manufactured into a vaccine.

Most recently, early preclinical results of the UQ COVID-19 vaccine candidate showed that it produced high levels of antibodies that can neutralize the virus.

The next critical phase for The University of Queensland’s COVID-19 vaccine launched on July 13, 2020, with 120 adult volunteers receiving the first dose of the vaccine at the Brisbane clinic of phase 1 clinical trials specialist, Nucleus Network.

On September 7, 2020, CSL Limited announced it would supply the Australian Government with 51 million doses of The University of Queensland’s COVID-19 vaccine candidate if it proves successful, under a head of agreement. CSL said it expects the first tranche of doses to be available by mid-2021, with additional doses following late 2021 and early 2022 if late-stage clinical trials are successful.

On December 10, 2020, Australia media reported: 'UQ, working in partnership with Australian global biotech company CSL, will abandon its current clinical trials. A source with knowledge of the clinical results said. However, HIV protein fragment posed "absolutely no health risk to people," they had identified that some trial participants who received the vaccine produced a partial antibody response to it. The partial antibody response had the potential to interfere with some HIV screening tests that look for the antibodies – leading to a false-positive test result.'

On December 11, 2020, the University announced 'following consultation with the Australian Government, CSL will not progress the vaccine candidate to Phase 2/3 clinical trials.'

'Phase 1 data also showed the generation of antibodies directed towards fragments of a protein (gp41), which is a component used to stabilize the vaccine. Trial participants were fully informed of the possibility of a partial immune response to this component, but it was unexpected that the levels induced would interfere with certain HIV tests. There is no possibility the vaccine causes infection, and routine follow-up tests confirmed there is no HIV present.'

'With advice from experts, CSL and UQ have worked through the implications that this issue presents to rolling out the vaccine into broad populations. It is generally agreed that significant changes would need to be made to well-established HIV testing procedures in the healthcare setting to accommodate this vaccine's rollout. Therefore, CSL and the Australian  Government have agreed vaccine development will not proceed to Phase 2/3 trials.'

UQ Vice-Chancellor, Professor Deborah Terry, added on December 11, 2020: 'while the outcome was disappointing, she was immensely proud of the UQ team who had shouldered a heavy burden of responsibility while the world watched on. “I also want to thank our many partners, our donors – including the Federal and Queensland Government – and of course the 216 Queenslanders who so willingly volunteered for the Phase 1 trials.'

The Queensland Government has provided $10 million in Advance Queensland funding for the vaccine project. The Federal Government has contributed $5 million, and more than $10 million has been provided by philanthropic and other donors.

Should the Phase 1 study prove to be successful towards the end of 2020, CSL will take full responsibility for the subsequent Phase 2b/3 clinical trial, which is expected to commence in late 2020. CSL will further develop, manufacture, and distribute UQ’s COVID-19 vaccine candidate.

For more information about CSL Limited, visit

University of Queensland (UQ) CSL Vaccine Candidate Indication

UQ-CSL V451 vaccine candidate is to prevent COVID-19 disease caused by infection with SARS-CoV-2. Early preclinical trials showed that the UQ COVID-19 vaccine candidate produced high antibody levels that can neutralize the coronavirus.

No pediatric, oncology, or pregnancy vaccine efficacy has been disclosed.

University of Queensland (UQ) CSL Vaccine Candidate News

December 11, 2020 - The University of Queensland and CSL today announce that the Phase 1 trial of the UQ-CSL v451 COVID-19 vaccine has shown that it elicits a robust response towards the virus has a strong safety profile. There were no serious adverse events or safety concerns reported in the 216 trial participants. However, following consultation with the Australian Government, CSL will not progress the vaccine candidate to Phase 2/3 clinical trials.  

December 10, 2020 - CEPI announced it supports the decision made by the University of Queensland (UQ) and CSL not to progress the v451 COVID-19 vaccine candidate into Phase 2/3 clinical trials. While the Phase 1 trial safety and immunogenicity data are positive, the issue of interference with certain HIV diagnostic tests means that the vaccine is not suitable for broad deployment. CEPI will therefore not continue to fund further development of the vaccine beyond completion of the Phase 1 clinical trial.

November 10, 2020 - CSL has begun manufacturing the COVID-19 candidate known as UQ-CSL V451, developed with the University of Queensland in Australia. That vaccine is currently in Phase 1 clinical trial, and doses will be held pending the results, with plans to manufacture more, if needed.

November 8, 2020 - CSL announced, 'Multiple doses of the UQ-CSL V451 vaccine candidate have already been manufactured at the Broadmeadows facility and are held in readiness to progress the vaccine to Phase 2b/3 clinical trials. The decision to proceed to the next clinical trial stage will be made once Phase 1 data has been released and analyzed. CSL’s Chief Scientific Officer, Dr. Andrew Nash, said, “Both campaigns are still technically challenging, but at this time, we are tracking well and expect to produce the AZD1222 and the UQ-CSL V451 vaccine for Australia by mid-2021."

September 7, 2020 – CSL Limited announced it had signed a Heads of Agreement with the Australian Government to supply 51 million doses of the University of Queensland’s COVID-19 vaccine candidate (V451).

August 27, 2020 - A call to arms has gone out to Queenslanders aged 56 and over to advance The University of Queensland’s COVID-19 vaccine project.

August 26, 2020 - Pre-clinical testing of The University of Queensland’s COVID-19 vaccine has produced positive indications about its potential effectiveness and manufacturability. Project co-leader Associate Professor Keith Chappell has reported to the International Society for Vaccines on data from animal trials conducted by Viroclinics-DDL in the Netherlands.

July 13, 2020 - Healthy adult volunteers have received the first dose of the UQ-CSL V451 vaccine at the Brisbane clinic of phase 1 clinical trials specialist, Nucleus Network.

June 5, 2020 - CEPI and The University of Queensland announced that they have entered into a new, significant partnering agreement to accelerate the development, manufacture, and distribution of a COVID-19 vaccine candidate that has been pioneered by researchers at UQ.

April 29, 2020 - The University of Queensland’s COVID-19 vaccine candidate has shown the ability to raise high levels of antibodies that can neutralize the virus in early pre-clinical testing.

April 9, 2020 - The UQ vaccine development team will partner with the Dutch company, Viroclinics Xplore, on the crucial pre-clinical studies.

February 23, 2020 - A University of Queensland team has met a key milestone in their fast-tracked research to develop a vaccine for the coronavirus, COVID-19. In just 3-weeks, the researchers' team has created their first vaccine candidate in the laboratory and will move immediately into further development before formal pre-clinical testing.

January 24, 2020 - The Coalition for Epidemic Preparedness Innovations (CEPI) requested UQ use its rapid response vaccine technology to develop a vaccine. The candidate being tested was produced within the first three weeks.

UQ COVID-19 Vaccine Candidate Clinical Trials

Clinical Trial NCT04495933: A Study on the Safety, Tolerability, and Immune Response of SARS-CoV-2 Sclamp (COVID-19) Vaccine in Healthy Adults - Last Update Posted: September 4, 2020.

  • A Phase 1, Randomised, Double-Blind, Placebo-Controlled, Dosage-Escalation, Single Centre Study to Evaluate the Safety and Immunogenicity of an Adjuvanted SARS-CoV-2 Sclamp Protein Subunit Vaccine in Healthy Adults Aged 18 to 55 Years Old and Healthy Older Adults, Aged 56 Years and Over
  • This trial will involve about 120 volunteers aged between 18 and 55 who will receive 2-doses of the UQ-CSL V451, with a proportion of participants receiving a placebo. The initial participant was dosed at the Brisbane Clinic.
  • The clinical batch of vaccine for use in the trial was manufactured in a close partnership between UQ and researchers at CSIRO’s advanced biologics production facility in Melbourne, with technical assistance from Australian biotech company CSL, Brisbane based Patheon, and the global biotech company Cytiva (formerly GE Life Sciences).
  • The UQ vaccine is expected to be available in 2021 should clinical trials be successful.