Arcturus Therapeutics Announces Positive Interim ARCT-021 (LUNAR-COV19) Phase 1/2 Study Results for Both Single Shot and Prime-boost Regimens, and Up to $220 Million in Additional Financial Commitments from Singapore
Based on interim Phase 1/2 results, a single 7.5 µg dose of ARCT-021, along with prime-boost regimens are selected to advance into later stage global clinical trials
Seroconversion in majority of participants receiving doses in the range of 5 µg to 7.5 µg; Geometric Mean Titer (GMT) levels for neutralizing antibodies in the range of convalescent plasma
Dose-dependent anti-spike IgG titers increased over time through approximately day 43; T cell reactivity to spike protein peptides, including receptor binding domain (RBD) observed
Favorable safety and tolerability profile in both younger (ages 21-55) and older (ages 56-80) subjects; no moderate or severe fevers
Lyophilized drug product on track for Phase 3 implementation
ARCT-021 Phase 1/2 study overview and results
ARCT-021 is being developed in collaboration with
The study is fully enrolled with 106 subjects, including older adult subjects. To date, 78 subjects have received at least one injection of ARCT-021, 36 subjects have received two injections (i.e., prime-boost), and 28 subjects have received placebo. Preliminary results are currently available from all single dose cohorts and the 5 µg younger adult prime-boost cohort up to at least day 36, with most subjects having completed day 57 post-injection.
Based on interim study results, a robust anti-spike protein IgG immune response was observed at all doses evaluated. PRNT50 GMT levels for neutralizing antibodies were within the range of titers observed in COVID-19 patient convalescent plasma. Furthermore, anti-spike IgG antibody titers have been dose-dependent, and increased through approximately day 43, confirming the effect seen in preclinical studies for STARR™ mRNA which exhibited increasing antibody titers over extended periods of time. Cytokine staining and ELISpot tests showed T cell responses to multiple peptide pools derived from the SARS-CoV-2 spike protein. The CD4+ response was Th1 dominant and the CD8+ response includes reactivity to the receptor binding domain.
ARCT-021 was generally well tolerated and had a favorable local and systemic adverse event (AE) profile. The majority of AEs have been mild; there have been no moderate (Grade 2) or severe (Grade 3) fevers at any dose and no severe (Grade 3) injection site reactions at doses being contemplated for advancement. No subjects have withdrawn from the study and there have been no serious adverse events deemed to be treatment related.
The study remains ongoing and the Company intends to provide additional results at a later date.
The Company’s lyophilized drug product remains on track for Phase 3 implementation. The novel lyophilization process technology has been successfully transferred to a cGMP manufacturing facility. Arcturus recently signed an agreement with Recipharm to support the manufacture of ARCT-021.
The Company is in discussions with the
“The promising Phase 1/2 study results indicate that ARCT-021 could be effective as a single administration, which differentiates this investigational vaccine from many other COVID-19 vaccines in development. ARCT-021 has the potential to provide important public health benefits by greatly facilitating broad administration across multiple populations worldwide,” said Professor
“We are very pleased with our preliminary ARCT-021 Phase 1/2 clinical study results, which demonstrate a favorable safety profile and both humoral and cellular immunity to the vaccine antigen, at relatively low dose levels. These results provide support for ARCT-021 having a differentiated emerging clinical profile, including as a single dose regimen. The non-viral LUNAR® delivery technology also has the ability to be dosed multiple times, if needed. We believe that our vaccine candidate could be an important contribution to controlling the global COVID-19 pandemic,” said
Arcturus announced an important manufacturing support agreement with Singapore’s EDB that includes a limited recourse loan of
“These funds provide the Company with additional resources to sustain rapid scale up of ARCT-021 to meet the requirements of our existing Israeli and
The Company will hold a conference call today, to further discuss the ARCT-021 vaccine candidate and other recent corporate updates as part of its third quarter announcement.
Founded in 2013 and based in
Forward Looking Statements
This press release contains forward-looking statements that involve substantial risks and uncertainties for purposes of the safe harbor provided by the Private Securities Litigation Reform Act of 1995. Any statements, other than statements of historical fact included in this press release, including those regarding strategy, future operations, collaborations, the likelihood of success, and the efficacy or safety of, ARCT-021, the ability to initiate or complete preclinical and clinical development programs, including as a result of the COVID-19 pandemic, the supply and delivery of any product or substance, the likelihood that any clinical data will be predictive of future clinical results or sufficient for regulatory approval, the ability to enroll subjects in clinical trials, the Company’s efforts to develop a vaccine against COVID-19 and therapeutic potential thereof based on the Company’s mRNA therapeutics, the timing of initiation of dosing in human trials of a vaccine against COVID-19, the ability of the Company to scale up manufacturing of vaccine doses, the potential manufacturing capabilities of the Company, the amount and timing of any draw down of loan amounts with the EDB, and the impact of general business and economic conditions are forward-looking statements. Arcturus may not actually achieve the plans, carry out the intentions or meet the expectations or projections disclosed in any forward-looking statements such as the foregoing and you should not place undue reliance on such forward-looking statements. Such statements are based on management’s current expectations and involve risks and uncertainties, including those discussed under the heading "Risk Factors" in Arcturus’ Annual Report on Form 10-K for the fiscal year ended
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