Arcturus Therapeutics Holdings Inc. has advanced its proprietary messenger RNA (mRNA) technology platforms—self-amplifying mRNA (STARR®) and lipid nanoparticle delivery (LUNAR®)—culminating in the world's first approved sa-mRNA COVID-19 vaccine, KOSTAIVE®, commercialized in Japan with regulatory approvals in Europe and the UK. The company is progressing a pipeline targeting rare genetic liver and respiratory diseases, including cystic fibrosis and ornithine transcarbamylase deficiency, through Phase 2 studies. Despite platform validation and a global manufacturing network, Arcturus faces regulatory delays in U.S. approvals and a substantial $430 million write-down related to its collaboration with CSL Seqirus amid changing COVID-19 market dynamics. Financial results for FY2025 show narrowing operating losses but persistent negative operating cash flow and free cash flow deficits, supported by strong liquidity.