19 August 2022 - - US-based clinical messenger RNA medicines company Arcturus Therapeutics Holdings Inc. (NASDAQ: ARCT) has released updated data from its ongoing ARCT-154 booster clinical trial.

The new results demonstrate broad neutralizing antibody response against Omicron variants of concern, including BA.5, lasting for up to at least six months after administration of low-dose (5 mcg) ARCT-154 booster.

Data shown above illustrate the ongoing antibody responses to single, low (5 microgram) booster doses of ARCT-154 in healthy adults previously vaccinated with Comirnaty. Samples taken at one, three, and six months after vaccination are shown.

After one month (day 29) and three months (day 91), neutralizing antibody responses to Omicron BA.5 were 33- and 20-fold elevated over pre-boost responses, respectively.

After six months (day 181), neutralizing antibody responses to Omicron BA.1, BA.2, BA.5 ranged from 22- to 52-fold, 25- to 55-fold, and 9 to 24-fold elevated over pre-boost responses, respectively.

These data show sustained neutralizing responses to antigenically distinct variants of concern, including Omicron BA.5, for at least six months after vaccination.

Founded in 2013 and based in San Diego, California, Arcturus Therapeutics Holdings Inc. (NASDAQ: ARCT) is a global late-stage clinical mRNA medicines and vaccines company with enabling technologies: (i) LUNAR lipid-mediated delivery, STARR mRNA Technology (samRNA) and mRNA drug substance along with drug product manufacturing expertise.

Arcturus' diverse pipeline of RNA therapeutic and vaccine candidates includes mRNA vaccine programs for SARS-CoV-2 (COVID-19) and Influenza, and other programs to potentially treat ornithine transcarbamylase deficiency, and cystic fibrosis, along with partnered programs including glycogen storage disease type III, and hepatitis B virus.

Arcturus' RNA therapeutics platforms can be applied toward multiple types of nucleic acid medicines including messenger RNA, small interfering RNA, replicon RNA, antisense RNA, microRNA, DNA, and gene editing therapeutics.