Summary of Arcturus Therapeutics Conference Call Company Overview - **Company**: Arcturus Therapeutics (NasdaqGM:ARCT) - **Event**: 2026 Conference on March 11, 2026 Key Points on Cystic Fibrosis (CF) Program - **Phase 2 Study Progress**: Completed three cohorts with successful dosing at 5 mg, 10 mg, and 15 mg, showing consistent tolerability across all levels [3][4] - **Study Duration**: The initial studies were 28-day trials, with plans to advance to a 12-week study to assess lung function improvements [4][5] - **Clinical Signals**: Early signals of biological proof of concept were observed, including decreases in mucus plugging as seen in high-resolution CT scans [4][5] - **Study Design Learnings**: The design of the upcoming 12-week study will incorporate multiple baseline measurements for lung function to control variability [10][11] - **Patient Selection**: The criteria for patient selection in the 12-week study will be narrowed to focus on subjects with moderate lung function, enhancing the potential for observable improvements [12][13] - **Endpoints**: The study will evaluate multiple endpoints, including FEV, LCI, and quality-of-life measures, alongside imaging data from CT scans [13][14] - **Regulatory Path**: The company anticipates leveraging data from a natural history study conducted by the CF Foundation for potential Phase 3 studies, depending on the outcomes of the 12-week study [35][36] Key Points on OTC Program - **Regulatory Clarity**: The company is seeking clarity from the FDA regarding the regulatory path for treating Ornithine Transcarbamylase deficiency, particularly in pediatric patients [42][43] - **Focus on Pediatric Population**: There is a strong emphasis on addressing the unmet medical needs of children, with plans to prioritize pediatric development [56][59] - **Innovative Assay**: Introduction of a new 15N ureagenesis assay to assess ammonia control in severe pediatric cases, which is a significant concern [50][52] Key Points on Respiratory Vaccine Franchise - **KOSTAIVE Updates**: The vaccine has received approval in the UK and is under arbitration regarding a milestone payment from CSL related to EU approval [65][70] - **Impact of Arbitration**: The outcome of the arbitration could significantly affect the company's cash runway, which currently extends to Q2 2028 without including potential milestone payments [75][76] Additional Insights - **Market Dynamics**: The company is expanding its CF study sites to Europe and the Middle East due to a higher prevalence of Class 1 CF subjects in those regions compared to the U.S. [33][34] - **Future Data Sharing**: The company plans to share data from the 12-week study after a certain number of subjects have been enrolled, although specific timelines have not been provided [39][40] - **Investor Communication**: The company is committed to keeping investors informed about ongoing developments and regulatory interactions, particularly regarding the OTC program and CF studies [72][73]