Arcturus Therapeutics Holdings Inc. Q3 FY2025 earnings call

• ARCT032 program: Phase II clinical trial in CF showed safety/tolerability with four of six class one CF participants in second cohort having mucus burden reduction. Ongoing third cohort at 15 mg, planning 12-week study in 2026 with 20 CF participants.
• ARCT810 program: Positive interim phase two data, preparing for regulatory meetings in 2026 to discuss pivotal trial strategy for pediatric and adult OTC deficiency.
• Costave COVID vaccine: Japanese partner Meiji Seika launched two-dose vial updated for JN1 variant XE. Phase three manuscript on ARCT2303 published showing robust immune response and co-administration safety with influenza.
• ARCT2304 program: Phase I study in young and older adults showed ARCT2304 induced humoral immune response with single and second dose, validating STAR SA mRNA platform.
• Financials: Cash runway extended into 2028 due to cost reductions and delay in CF trial commencement.

Revenues for the three and nine months ended 09/30/2025 were $17.2 million and $74.8 million, respectively, down from $41.7 million and $129.5 million in the same periods of 2024. This decline was mainly due to reduced revenues from the CSL collaboration. Total operating expenses for the three months ended 09/30/2025 were $33.7 million vs. $52.4 million in 2024. R&D expenses for the three months were $23.3 million vs. $39.1 million in 2024, driven by lower manufacturing and clinical costs. G&A expenses for the three months were $10.4 million vs. $13.3 million in 2024, due to reduced share-based comp and payroll.

• Plan to initiate 12-week CF study for ARCT032 in 2026.
• Prepare for regulatory meetings in 2026 regarding ARCT810's pivotal trial strategy for pediatric and adult populations.
• Cash runway extended into 2028 based on cost reductions and trial delay.

• Costave BLA filing delayed indefinitely due to FDA regulatory changes.
• Uncertain commercial visibility for Costave in the US.
• Regulatory uncertainties in aligning pivotal trial protocols for OTC deficiency in pediatric and adult populations.

Q: With the upcoming 15 mg dose, what metrics drive go/no-go for phase two?

A: Safety and tolerability are key for the 15 mg cohort. If well tolerated, it may be selected for the 12-week study. Success in the 12-week study would be continued mucus plug reduction and potential lung function improvements.

Q: Any updates on Costave guidance for revenue realization?

A: Typically no guidance on Costave commercial revenue. Meiji ordered ~1 million doses in Q4 2025, delivered in Oct-Nov, with update likely at year-end call in March