Arcturus Therapeutics Shares Rise After OTC Deficiency Data, Citigroup Upgrade

03:08 PM EDT, 09/24/2026 (MT Newswires) -- Arcturus Therapeutics (ARCT) shares rose 6.3% in Thursday afternoon trading, a day after it reported interim phase 2 results for ARCT-810 in OTC deficiency and unveiled LUNAR 2.0, its next-generation mRNA delivery platform. Separately, Citigroup upgraded the stock to buy from neutral and raised its price target to $20 from $8. ARCT-810 was generally safe and well tolerated, reduced or maintained fasting ammonia within the normal range, and reduced glutamine, with the 0.5 mg/kg dose group reaching normal glutamine levels. LUNAR 2.0 showed a 40-fold improvement over LUNAR 1.0 in expressing human erythropoietin in primate studies. Arcturus said its next candidate, ARCT-2601, built on LUNAR 2.0, will begin dosing near year-end in OTC deficiency patients aged 12 and older, following favorable FDA feedback. Additionally, Arcturus agreed to acquire myNEO, with the transaction expected to close in October. The acquisition will add an AI computational engine to support drug design, according to the company. Financial terms were not disclosed. Price: 14.14, Change: +0.84, Percent Change: +6.32