Arcturus reports Q2 2026 results, regains KOSTAIVE rights from CSL Seqirus

Arcturus Therapeutics Holdings reported financial results for the quarter ended June 30, 2026, alongside pipeline updates on August 6, 2026.

For ARCT-032, an inhaled mRNA candidate for cystic fibrosis, the company said the drug continues to be tested in people with Class I CF mutations, with Cohort 4 evaluating 10 mg daily dosing by inhalation over 12 weeks while monitoring safety and early clinical benefit measures including ppFEV1, lung clearance index, quality-of-life metrics, and HRCT imaging.¹ Arcturus said enrollment is proceeding as expected, with active screening across sites in the U.S., Israel, and Turkey, countries the company noted have a high prevalence of Class I/null CF mutations.¹ A decision on advancing ARCT-032 into Phase 3 is expected in the fourth quarter of 2026, which would trigger expanded involvement from Thermo Fisher.¹ Under an existing collaboration, if Phase 2 results are positive, Arcturus expects to run its Phase 3 program through Thermo Fisher's PPD clinical research business, and Thermo Fisher would receive exclusive commercial manufacturing rights pending regulatory approval of ARCT-032.¹

For ARCT-810, targeting OTC deficiency, enrollment and dosing in the Phase 2 study are complete, with the company evaluating supplementary data ahead of an End-of-Phase 2 meeting on adult and pediatric development, and a data and regulatory plan expected later in the third quarter of 2026.¹

Separately, Arcturus and CSL Seqirus ended their self-amplifying mRNA collaboration through a termination and settlement agreement, returning global rights to KOSTAIVE and the broader infectious disease vaccine portfolio to Arcturus, subject to existing Japan arrangements with Meiji Seika Pharma for the 2026-2027 season.¹ CSL Seqirus will pay Arcturus $12 million in cash and release it from R&D credit liabilities valued at approximately $16 million.¹

On the balance sheet, cash and equivalents were $191.5 million as of June 30, 2026, down from $230.9 million at year-end 2025.¹ CFO Dennis Mulroy said the company maintains a cash runway of over two and a half years through year end 2028.¹