Arcturus Therapeutics Holdings Inc.

What they do

Arcturus develops mRNA therapeutics for rare diseases using its STARR self-amplifying mRNA platform and LUNAR lipid nanoparticle delivery system. Its internal pipeline is led by ARCT-032 for cystic fibrosis and ARCT-810 for ornithine transcarbamylase (OTC) deficiency, both in Phase 2. It also holds rights to KOSTAIVE, a self-amplifying mRNA COVID-19 vaccine approved in Japan, the EU and the UK, plus broader infectious disease vaccine programs.

Revenue drivers

• Collaboration and license revenue — Historically the dominant revenue source, tied to partnered vaccine programs such as CSL Seqirus; annual revenue fell from $206.0M in 2022 to $82.0M in 2025 as collaboration activity wound down.
• KOSTAIVE / sa-mRNA vaccine portfolio — KOSTAIVE is approved in Japan, the EU and the UK, with Japan sales beginning October 2024; Arcturus regained global rights in the 2026 CSL Seqirus termination, subject to existing Meiji arrangements in Japan for the 2026-2027 season.
• Grant and other revenue — A small residual line; quarterly revenue declined from $17.2M in Q3 2025 to $2.1M in Q1 2026 and $3.0M in Q2 2026, showing how thin non-collaboration revenue is.

Recent performance

Q2 2026 revenue was $3.0M, down from $17.2M in Q3 2025 and $7.2M in Q4 2025. Full-year 2025 revenue was $82.0M with a net loss of $65.8M and operating cash outflow of $74.3M. At June 30, 2026 the company reported $191.5M in cash and equivalents, $224.3M in total assets and $52.5M in total liabilities, with shareholder equity of $171.8M. The CSL Seqirus termination and settlement brought a one-time $12M cash payment and release of roughly $16M in liabilities and R&D credits.

Strategy

Arcturus is prioritizing its wholly owned rare disease programs: ARCT-032 in CF and ARCT-810 in OTC deficiency, with existing Phase 2 studies. It signed a strategic collaboration with Thermo Fisher Scientific covering Phase 3 manufacturing and the PPD clinical research business, with exclusive commercial manufacturing rights contingent on regulatory approval. After regaining global rights to KOSTAIVE and the infectious disease portfolio (seasonal influenza, pandemic influenza, RSV and EBV), management says it will evaluate development, commercialization and partnering options for those assets. Management cites a cash runway of over two and a half years, through year-end 2028.

Risks

• Collaboration partner losses — CSL Limited recorded an approximately $430 million write-down on the Arcturus collaboration in February 2026, citing declining COVID-19 disease burden and more onerous U.S. regulatory requirements, and the collaboration was subsequently terminated.
• Thin and shrinking revenue — Revenue fell from $206.0M in 2022 to $82.0M in 2025 and to $3.0M in Q2 2026, leaving the company dependent on cash reserves and future partnering rather than current operations.
• Clinical and regulatory uncertainty — ARCT-032 and ARCT-810 are both still in Phase 2, and the decision to advance ARCT-032 to Phase 3 is not expected until Q4 2026.
• Ongoing cash consumption — Operating cash flow was negative $74.3M in 2025, meaning continued losses would draw down the $191.5M cash balance reported at June 30, 2026.

Outlook

Management expects an ARCT-032 Phase 3 go/no-go decision in Q4 2026 and says Phase 3 would run through Thermo Fisher's PPD business. ARCT-810 Phase 2 data and the regulatory plan, including preparation for an End-of-Phase 2 meeting, are expected later in Q3 2026. Management states a cash runway of over two and a half years, through year-end 2028.