On Nov. 28, 2023, CSL and Arcturus Therapeutics announced that Japan’s Ministry of Health, Labor and Welfare (MHLW) had granted approval for ARCT-154, a self-amplifying mRNA (sa-mRNA) COVID-19 vaccine for initial vaccination and booster for adults 18 years and older.

The approval was based on positive clinical data from several ARCT-154 studies, including an ongoing 16,000 subject efficacy study performed in Vietnam as well as a Phase 3 COVID-19 booster trial, which achieved higher immunogenicity results and a favorable safety profile compared to a standard mRNA COVID-19 vaccine comparator. Initial study results were published in MedRxiv.