Arcturus Therapeutics

Arcturus Therapeutics is an American biotechnology company focused on the discovery, development and commercialization of RNA medicines. Founded in 2013 by Joseph Payne and Pad Chivukula, the company is headquartered in San Diego, California, and concentrates on therapies for rare diseases, infectious diseases and selected respiratory or gastrointestinal conditions. Its technology portfolio is built around proprietary methods for transporting nucleic-acid medicines into cells, particularly the Lunar lipid nanoparticle platform and the self-replicating mRNA technology known as Starr. The Lunar platform is intended to encapsulate and deliver RNA or DNA to selected cells in the body. Once the payload reaches the target cell and is released, the cell's own biological machinery can use the RNA to produce a therapeutic protein or otherwise generate a desired biological effect. The approach is designed to address a central challenge in RNA medicine: delivering nucleic acids efficiently while limiting unwanted immune responses and toxicity. Arcturus has applied the platform to messenger RNA, small interfering RNA, gene-editing RNA, antisense oligonucleotides and microRNA-related medicines. Rare-disease programs have been an important part of the company's development strategy. ARCT-810, an investigational mRNA therapy using Lunar delivery, was developed for ornithine transcarbamylase deficiency, a urea-cycle disorder in which the body cannot adequately remove ammonia-producing waste. The program received United States orphan-drug designation in 2019, and the FDA allowed an investigational new drug application to proceed in 2020. Patient trials began in June 2020. Arcturus has also described programs directed at cystic fibrosis, glycogen storage disease type III and other rare-disease targets, including projects conducted with the Cystic Fibrosis Foundation and Ultragenyx. During the COVID-19 pandemic, Arcturus partnered with Duke-NUS Medical School to develop a vaccine combining self-replicating mRNA with Lunar delivery. The program was initially known as Lunar-COV19 and was later associated with candidates including ARCT-021 and the next-generation candidates ARCT-154 and ARCT-165. Manufacturing and development support came from contract organizations including Catalent and Recipharm. Clinical testing in healthy volunteers began in July 2020, followed by progression toward Phase 2 studies in the United States and Singapore. A related vaccine based on the ARCT-154 program received authorization in Japan in 2023 and authorization in the European Union in 2025, according to the company's referenced encyclopedia record. Beyond COVID-19, Arcturus has pursued self-replicating mRNA vaccine research for influenza through its Lunar-FLU program. It has also reported collaborative programs in hepatitis B, non-alcoholic steatohepatitis and other gastrointestinal disorders, vaccines and therapeutics for infectious diseases, and rare-disease applications. These collaborations have involved organizations such as Janssen, Takeda, Synthetic Genomics and Ultragenyx. The company underwent a significant corporate and governance episode after merging with Israeli pharmaceutical company Alcobra Ltd. in September 2017. In February 2018, the Arcturus board dismissed Joseph Payne as president and chief executive officer. Payne subsequently pursued legal proceedings concerning shareholder rights and a requested shareholders meeting. Litigation involving Payne, his nominees and the company's board was resolved in May 2018 through a settlement that added four directors, removed four existing directors, provided mutual releases and ended the pending litigation. Arcturus has since continued operating as an RNA-medicines biotechnology company, with its commercial and strategic identity centered on nucleic-acid delivery, rare diseases and infectious-disease vaccines.

Arcturus Therapeutics was founded in 2013 in San Diego by Joseph Payne and Pad Chivukula. From its early development, the company focused on the problem of delivering nucleic-acid medicines into specific cells. Its principal delivery technology, Lunar, is a lipid nanoparticle system designed to transport RNA or DNA into the body and release the payload inside target cells. This approach was developed to improve the practical use of RNA medicines, whose clinical utility depends not only on the design of the genetic message but also on protecting and delivering it effectively. The Lunar platform has been investigated for messenger RNA, small interfering RNA, gene-editing RNA, antisense oligonucleotides and microRNA-related applications. Early research described delivery of ornithine transcarbamylase messenger RNA to liver cells and collaborative work involving Factor IX messenger RNA, supporting the possibility of using the platform for protein-replacement therapies. Research collaborations also explored nanoparticle-delivered mRNA in oncology, including work involving intracerebral glioma models. These efforts helped establish the company's broader identity as an RNA-platform business rather than a single-product pharmaceutical company. Arcturus's rare-disease work included ARCT-810, an investigational Lunar-enabled mRNA therapy for ornithine transcarbamylase deficiency. The disorder is a urea-cycle condition that can impair the body's ability to process nitrogenous waste and may lead to toxic ammonia accumulation. The program received FDA orphan-drug designation in 2019. In April 2020, the FDA allowed the company's investigational new drug application for a Phase 1b study to proceed, and clinical testing in patients began in June of that year. Other reported rare-disease projects included Lunar-CF for cystic fibrosis and Lunar-GSD for glycogen storage disease type III, with the latter developed in collaboration with Ultragenyx. A broader Lunar-Rare collaboration with Ultragenyx was intended to generate therapeutic candidates for additional rare-disease targets. The company's corporate structure changed in September 2017 through a merger with Alcobra Ltd., an Israeli pharmaceutical company. The following year brought a contested leadership and board episode. In February 2018, the Arcturus board dismissed co-founder Joseph Payne as president and chief executive officer. Payne sought a shareholders meeting and brought proceedings in an Israeli court after, according to the referenced account, his requests were not acted upon. The court upheld shareholder rights by permitting the meeting. In April, the board filed its own complaint against Payne and his board nominees. The dispute ended in May 2018 with a settlement. Peter Farrell, Andrew Sassine, James Barlow and Magda Marquet were appointed as directors, while Stuart Collinson, Daniel Geffken, David Shapiro and Craig Willett resigned. The settlement also included mutual releases and termination of the pending litigation. The COVID-19 pandemic redirected substantial attention toward Arcturus's vaccine capabilities. Working with Duke-NUS Medical School, the company developed Lunar-COV19, a vaccine combining the Lunar delivery system with self-replicating mRNA. Self-replicating RNA is designed to amplify the production of an encoded antigen inside cells, potentially allowing a lower dose or extending antigen expression compared with conventional mRNA approaches. Arcturus worked with Catalent and Recipharm on manufacturing multiple batches. Clinical trials in healthy volunteers began in July 2020, and regulators in the United States and Singapore approved progression toward Phase 2 evaluation in December 2020. The vaccine program subsequently developed into next-generation candidates including ARCT-154 and ARCT-165. ARCT-154 entered a clinical trial in Vietnam in August 2021, while the company also announced applications for Phase I/II studies involving ARCT-165 and ARCT-154 in Singapore. The ARCT-154 program later achieved regulatory authorizations in Japan in 2023 and the European Union in 2025, according to the referenced Wikipedia record. Arcturus has also maintained a pipeline beyond COVID-19. Lunar-FLU combines the company's self-replicating mRNA technology, known as Starr, with Lunar delivery for a proposed influenza vaccine. Lunar-HBV was described as a collaboration with Janssen for hepatitis B medicines. Lunar-NASH was developed with Takeda for non-alcoholic steatohepatitis and other gastrointestinal disorders. Collaborations with Synthetic Genomics covered improved vaccine and therapeutic technology as well as infectious-disease prophylaxis. Taken together, these programs show a strategy based on reusing delivery and RNA-design capabilities across rare diseases, respiratory diseases, vaccines and other therapeutic areas. The company remains an active RNA-medicines biotechnology enterprise headquartered in San Diego.

1. 2025ARCT-154 vaccine authorized in the European Union

   The referenced company record reports European Union authorization for the ARCT-154 vaccine program.

   Source
2. 2023ARCT-154 vaccine authorized in Japan

   The ARCT-154 vaccine program received authorization in Japan.

   Source
3. 2021Next-generation COVID-19 candidates enter development

   ARCT-154 began clinical testing in Vietnam, while Phase I/II applications involving ARCT-154 and ARCT-165 were pursued in Singapore.

   Source
4. 2020ARCT-810 clinical development advances

   The FDA allowed the investigational new drug application for a Phase 1b patient study to proceed; patient trials began in June.

   Source
5. 2020Lunar-COV19 enters human testing

   Arcturus began clinical trials of its self-replicating mRNA COVID-19 vaccine candidate in healthy volunteers.

   Source
6. 2019ARCT-810 receives orphan-drug designation

   The FDA granted orphan-drug designation to ARCT-810 for ornithine transcarbamylase deficiency.

   Source
7. 2018Board and shareholder dispute settled

   A settlement ended litigation involving Joseph Payne and the board, added four directors and led to the resignation of four others.

   Source
8. 2017Merger with Alcobra Ltd.

   Arcturus merged with the Israeli pharmaceutical company Alcobra Ltd., creating a major corporate transition in its history.

   Source
9. 2013Arcturus Therapeutics founded

   Joseph Payne and Pad Chivukula founded the company in San Diego to develop RNA medicines and nucleic-acid delivery technologies.

   Source

A specialist RNA-medicines biotechnology company positioned around proprietary nucleic-acid delivery, self-replicating mRNA and applications in rare diseases and infectious diseases.

• LunarLipid nanoparticle RNA delivery platform

  Lunar is Arcturus's proprietary lipid nanoparticle delivery system. It is designed to carry RNA or DNA into selected cells and release the payload intracellularly, where cellular machinery can produce a therapeutic protein or create another intended biological effect. The platform has been investigated for mRNA, siRNA, gene-editing RNA, antisense oligonucleotide and microRNA applications. Reported research has included liver delivery for metabolic and protein-replacement concepts, as well as experimental oncology applications.

• StarrSelf-replicating mRNA technology

  Starr is Arcturus's self-replicating mRNA technology. It is intended to enable intracellular amplification of an encoded message, potentially extending antigen or protein expression and supporting lower-dose approaches. The technology was combined with Lunar in the company's COVID-19 vaccine program and is also being applied to the Lunar-FLU influenza vaccine concept.

• ARCT-810Rare-disease mRNA therapeutic2019

  ARCT-810 is an investigational mRNA medicine using Lunar delivery for ornithine transcarbamylase deficiency, a urea-cycle disorder. The program is intended to deliver messenger RNA to liver cells so they can produce the relevant enzyme. It received FDA orphan-drug designation in 2019, and an investigational new drug application for a Phase 1b study was allowed to proceed in 2020.

• Lunar-COV19COVID-19 vaccine program2020

  Lunar-COV19 was Arcturus's initial COVID-19 vaccine program, developed with Duke-NUS Medical School. It combined self-replicating mRNA with the Lunar lipid nanoparticle system. Clinical testing in healthy volunteers began in July 2020, followed by regulatory progression toward Phase 2 studies in the United States and Singapore. The program led to later-generation candidates including ARCT-154 and ARCT-165.

• ARCT-154Self-replicating mRNA COVID-19 vaccine2021

  ARCT-154 is a next-generation COVID-19 vaccine candidate derived from Arcturus's self-replicating mRNA and Lunar delivery work. The candidate entered clinical development in Vietnam in 2021 and was also included in regulatory applications in Singapore. The referenced record states that the vaccine received authorization in Japan in 2023 and in the European Union in 2025.

• ARCT-165Self-replicating mRNA COVID-19 vaccine candidate2021

  ARCT-165 is a next-generation COVID-19 vaccine candidate associated with Arcturus's self-replicating mRNA platform. The company announced an application for a Phase I/II clinical study in Singapore in 2021.

• Lunar-CFCystic-fibrosis therapeutic program

  Lunar-CF is a research program intended to apply Arcturus's delivery technology to cystic fibrosis. It was described as a collaboration with the Cystic Fibrosis Foundation.

• Lunar-FLUInfluenza vaccine program

  Lunar-FLU is Arcturus's wholly owned influenza vaccine program. It combines the Starr self-replicating mRNA technology with Lunar delivery to develop a prophylactic vaccine against influenza.

• Lunar-GSDRare-disease therapeutic program

  Lunar-GSD is a collaborative program with Ultragenyx focused on glycogen storage disease type III and the potential use of RNA medicines for this rare metabolic disorder.

• Lunar-HBVHepatitis B therapeutic program

  Lunar-HBV was described as a collaboration with Janssen to develop medicines for hepatitis B virus infection using Arcturus's RNA delivery capabilities.

• Lunar-NASHGastrointestinal and metabolic disease program

  Lunar-NASH was a collaboration with Takeda focused on non-alcoholic steatohepatitis and other gastrointestinal disorders. The program was intended to explore RNA medicines enabled by the Lunar platform.

• 2021Development of next-generation COVID-19 candidatesGeneration change

  Arcturus sought to extend its self-replicating mRNA vaccine work beyond the initial Lunar-COV19 program.

  What changed. ARCT-154 entered clinical testing in Vietnam, while applications involving ARCT-154 and ARCT-165 were pursued for Phase I/II studies in Singapore.

  Aftermath. The ARCT-154 program later received authorizations in Japan and the European Union according to the referenced record.

  Source
• 2020Initiation of Lunar-COV19 clinical developmentProduct launch

  The COVID-19 pandemic created demand for rapidly deployable vaccine platforms, and Arcturus had combined its Lunar delivery system with self-replicating mRNA in partnership with Duke-NUS Medical School.

  What changed. The company began clinical testing in healthy volunteers and subsequently advanced toward Phase 2 evaluation in the United States and Singapore.

  Aftermath. The program evolved into next-generation candidates including ARCT-154 and ARCT-165.

  Source
• 2018Settlement restructures the boardOther

  Following Joseph Payne's dismissal and disputes concerning a shareholders meeting, Payne and the board became involved in litigation.

  What changed. The May 2018 settlement appointed Peter Farrell, Andrew Sassine, James Barlow and Magda Marquet as directors and resulted in the resignation of Stuart Collinson, Daniel Geffken, David Shapiro and Craig Willett.

  Aftermath. The parties mutually released claims and agreed to terminate the pending litigation.

  Source
• 2017Merger with Alcobra Ltd.M&A

  Arcturus pursued a corporate combination with Alcobra Ltd., an Israeli pharmaceutical company.

  What changed. The two companies merged in September 2017.

  Aftermath. The transaction preceded a major leadership and governance dispute in 2018.

  Source

• 2025ARCT-154 authorized in the European Union

  The referenced company record states that the ARCT-154 vaccine received authorization in the European Union.

  RegulationProduct launch
  Source
• 2023ARCT-154 authorized in Japan

  A vaccine based on the ARCT-154 program received authorization in Japan.

  RegulationProduct launch
  Source
• 2021ARCT-154 and ARCT-165 advance as next-generation vaccine candidates

  Arcturus initiated or sought clinical studies in Vietnam and Singapore for next-generation COVID-19 vaccine candidates ARCT-154 and ARCT-165.

  Product generationProduct launch
  Source
• 2020FDA allows ARCT-810 clinical development to proceed

  The United States FDA allowed Arcturus's investigational new drug application for a Phase 1b study of ARCT-810 in patients with ornithine transcarbamylase deficiency to proceed.

  Regulation
  Source
• 2020Lunar-COV19 enters clinical testing

  The company's COVID-19 vaccine candidate, developed with Duke-NUS Medical School, began clinical trials in healthy volunteers.

  Product launch
  Source
• 2020Phase 2 development authorized for COVID-19 vaccine candidate

  Regulators in the United States and Singapore approved progression toward Phase 2 studies for Arcturus's COVID-19 vaccine program.

  RegulationProduct generation
  Source
• 2019ARCT-810 receives orphan-drug designation

  The FDA granted orphan-drug designation to the company's investigational ARCT-810 therapy for ornithine transcarbamylase deficiency.

  Regulation
  Source
• 2018Joseph Payne removed as president and chief executive officer

  The company's board dismissed co-founder Joseph Payne from his leadership roles, triggering a dispute over governance and shareholder rights.

  Leadership changeLawsuit
  Source
• 2018Shareholder and board litigation resolved through settlement

  A settlement reorganized the board, appointed four new directors, removed four existing directors and ended pending litigation between the company and Joseph Payne.

  LawsuitLeadership change
  Source
• 2017Arcturus merges with Alcobra

  Arcturus Therapeutics completed a merger with Israeli pharmaceutical company Alcobra Ltd., creating an important corporate transition in the company's development.

  M&A
  Source

1. Arcturus Therapeutics
2. Arcturus Therapeutics official website