COVID-19 Vaccine Shelved After False HIV Positives Affirms Need for Multiple Vaccines
Courtesy of AstraZeneca
A COVID-19 vaccine being developed by CSL Ltd., and the University of Queensland was scrapped this week after numerous vaccine recipients reported receiving false positives on certain HIV tests, according to the Wall Street Journal. The Australian government had originally agreed to buy 51 million doses of the product, v451.
Australian Health Department Secretary Brendan Murphy told the Journal that the country can take its time, as it has relatively controlled the virus.
V451 utilized molecular clamp technology, which prevents spike proteins on the coronavirus from uncoiling. Those who receive the vaccine presumably develop antibodies to the coiled shape. However, v451 involved the use of an HIV protein, resulting in false positives on tests.
The researchers behind the vaccine say it will take another year to re-engineer the vaccine and resolve the issue. If v451 were to roll out, regardless, HIV-testing procedures would need to change significantly. Authorities ultimately decided that it was not worth progressing the vaccine to an advanced clinical trial.
Australian Prime Minister Scott Morrison said today that Australia has since increased its orders for two vaccines that are still under consideration. One of the products, which stems from Oxford University and AstraZeneca, is being produced by CSL in Australia to limit supply chain risks. Australian Health Minister Greg Hunt says the country has access to more than 140 million doses.
AstraZeneca announced back in November that it had seen positive high-level results from an interim analysis of clinical trials looking at its COVID-19 vaccine, AZD1222, in the U.K. and Brazil. It reached its primary endpoint, indicating that it is highly effective in preventing the disease, and no hospitalizations or severe cases of COVID-19 were reported in participants who received the vaccine. A total of 131 COVID-19 cases were examined in the interim analysis.
One dosing regimen showed vaccine efficacy of 90% when AZD1222 was given as a half dose, followed by a full dose one month apart.
“These findings show that we have an effective vaccine that will save many lives,” said Professor Andrew Pollard, Chief Investigator of the Oxford Vaccine Trial at Oxford, at the time of the announcement. “Excitingly, we’ve found that one of our dosing regimens maybe around 90% effective and if this dosing regime is used, more people could be vaccinated with planned vaccine supply. Today’s announcement is only possible thanks to the many volunteers in our trial, and the hard working and talented team of researchers based around the world.”
Upon the announcement, AstraZeneca added that it would begin preparing a regulatory submission of the data to authorities around the world that have a framework in place for conditional or early approval. Clinical trials are also being carried out in countries including the U.S., Japan, Russia, and South Africa.
“Today marks an important milestone in our fight against the pandemic,” said Pascal Soriot, chief executive officer of AstraZeneca, at the time of the announcement. “This vaccine’s efficacy and safety confirm that it will be highly effective against COVID-19 and will have an immediate impact on this public health emergency. Furthermore, the vaccine’s simple supply chain and our no-profit pledge and commitment to broad, equitable and timely access means it will be affordable and globally available, supplying hundreds of millions of doses on approval.”
AstraZeneca is making progress in manufacturing with a capacity of up to 3 billion doses of the vaccine in 2021 on a rolling basis.