The ARCT-154 vaccine was administered at a significantly lower dose of 5ÎĽg as against Comirnaty at 30ÎĽg. Credit: Viacheslav Lopatin / Shutterstock.

CSL and Arcturus Therapeutics have published follow-up analysis from a Phase III clinical trial indicating that ARCT-154, a self-amplifying messenger RNA (sa-mRNA) Covid-19 vaccine, offers a longer duration of immunity as a booster dose.

The study compared ARCT-154’s immunogenicity against that of the conventional mRNA Covid-19 vaccine Comirnaty one, three and six months after a booster dose.

Go deeper with GlobalData

Premium Insights

The gold standard of business intelligence.

Find out more

Related Company Profiles

View all

The randomised, double-blind trial assessed the vaccine’s ability to induce immunity against both the original Wuhan strain and the Omicron BA.4/5 variant.

ARCT-154 was administered at a significantly lower dose of 5ÎĽg as against Comirnaty at 30ÎĽg.

Six months after vaccination, the analysis showed that ARCT-154 induced a longer immune response and had an advantage in antibody persistence over Comirnaty.

See Also:

Participants in both groups initially had similar geometric mean titers (GMTs) of surrogate virus-neutralising antibodies against the Wuhan-Hu-1 strain.

How well do you really know your competitors?

Access the most comprehensive Company Profiles on the market, powered by GlobalData. Save hours of research. Gain competitive edge.

Company Profile – free sample

Thank you!

Your download email will arrive shortly

Not ready to buy yet? Download a free sample

We are confident about the unique quality of our Company Profiles. However, we want you to make the most beneficial decision for your business, so we offer a free sample that you can download by submitting the below form

By GlobalData
Visit our Privacy Policy for more information about our services, how we may use, process and share your personal data, including information of your rights in respect of your personal data and how you can unsubscribe from future marketing communications. Our services are intended for corporate subscribers and you warrant that the email address submitted is your corporate email address.

One month after receiving the booster, the ARCT-154 arm showed a higher immune response with a GMT of 5,390 versus the Comirnaty group’s GMT of 3,738, resulting in a GMT ratio of 1.44.

By day 91, titers were equal to or greater than those on day 29 in 205 of the 369 ARCT-154 recipients, but only in 108 of the 356 Comirnaty recipients.

The different rates of antibody waning meant that by day 181, the GMTs of ARCT-154 recipients were 4,119, maintaining a GMT ratio of 2.21 between the vaccine groups.

A similar pattern of superior immunogenicity and a slower decline in neutralising antibodies following the ARCT-154 vaccine was also observed for the Omicron BA.4/5 variant.

CSL Vaccines Innovation Unit senior vice-president Jonathan Edelman said: “These results further support sa-mRNA’s differentiating attribute to provide prolonged protection against Covid-19 at lower doses.

“Protecting the global public from viral respiratory diseases remains a top priority for us, and we look forward to continuing to collect and share data at the twelve-month post-booster mark.”