Arcturus Therapeutics Holdings Inc.

Greetings and welcome to the Arcturus Therapeutics Third Quarter 2020 Earnings Call. At this time, all participants are in a listen-only mode. A brief question and answer session will follow the formal presentation. If anyone should require operator assistance during the conference, please press star zero on your telephone keypad. As a reminder, this conference is being recorded. It is now my pleasure to introduce your host, Neda Safar Suda, Head of Investor Relations, Public Relations and Marketing. Thank you. You may begin.

Thank you, operator, and good afternoon, everyone. We are joined today by Joseph Payne, President and CEO, Andy Sassine, CFO, Dr. Pat Chivukula, CSO and COO, and Dr. Steve Hughes, our Chief Development Officer. Before we begin, I would like to remind everyone that except for statements of historical facts, the statements made by management and any responses to questions on this conference call constitute 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 the statements of historical facts included in this communication including those regarding the company's supply agreements and potential supply agreements, the company's future manufacturing and other operations, the status and results of clinical development programs, the planned initiation, design or completion of clinical trials, the likelihood of the success of company's coronavirus COVID-19 vaccine candidate or other candidates, and the company's current and future cash and financial position, or forward-looking statements. Actual results and performance could differ materially from those projected in any forward-looking statements as a result of many factors, including without limitation, an inability to develop and market product candidates, unexpected clinical results, and general market conditions that may prevent such achievements or performance. Such statements are based on management's current expectations and involve risks and uncertainties, including those discussed under the heading risk factors in ArcTrace's annual report on Form 10-K for the fiscal year ended December 31, 2019, filed with the SEC on March 16, 2020, and in subsequent filings with our submissions or the SEC. Except as otherwise required by law, we disclaim any intention or obligation to update or revise any forward-looking statements which speak only as of the date they were made, whether as a result of new information, future events, or circumstances, or otherwise. Now it is my pleasure to pass the call to Joe Payne, President and CEO. Joe, please go ahead.

Hey, thank you, Netta. Good afternoon to all. Thank you for joining us. Arcturus' quarterly call today. To begin, and right off the bat, I'd like to congratulate Pfizer and BioNTech for the significant milestone announced earlier today. Congratulations to them, their scientists, and their team for this accomplishment. We believe this is exceptional validation of messenger RNA therapeutics and vaccines, and Arcturus is very fortunate to be part of this messenger RNA therapeutics community. especially since we're all working together in this global effort to vaccinate and protect just each of us from COVID-19. Thanks to our partners in Israel and Singapore in supporting us. Well, Arcturus has made substantial recent pipeline progress, highlighted by our two most advanced clinical programs. ARCTO21 is our COVID-19 self-transcribing and replicating RNA, our STAR mRNA vaccine candidate, and ARCT810, our therapeutic candidate for OTC deficiency or ornithine transcarbanolase deficiency. We're very pleased today to announce encouraging initial clinical results from both of these programs, and we've also made strong progress advancing our earlier stage pipelines, including our CF program. or cystic fibrosis. I'll begin with ARCTO21, which is also known as LUNR-COV19 or COV19. To remind you, ARCTO21 is being developed in collaboration with the Duke NUS Medical School, and development activities are being performed in Singapore. Today, we're excited to report for the first time preliminary clinical results from our ongoing Phase 1-2 clinical study. The objectives of this study are to evaluate safety and tolerability, and the humoral and cellular immune response, and to determine the dose and administration regimens to be evaluated in further clinical development. Our encouraging phase one slash two results, to which Steve will detail in a few minutes, our chief development officer, they provide further support to suggest that our self-replicating mRNA-based investigational vaccine, that this approach using our proprietary STAR mRNA technology may produce protective immunity at low mRNA doses and potentially with only a single administration. Now, based on our interim clinical data, we plan to advance a low single dose of 7.5 micrograms along with prime boost regimens. We saw 100% seroconversion of IgG binding antibodies in younger adults. One out of five older adult participants has not yet seroconverted. The observed geometric mean titers in all of these cohorts exceeded 2,500. So the 7.5 microgram dose level that's been selected Focusing in on that specific dose, our GMT or geometric mean titer for this group or the GMT exceeded 15,000 for younger adults and exceeded 2,000 in older adults at this dose. The IgG binding antibodies continue to increase over time in humans. This is in a similar manner to what we observed in preclinical animal models. We consider that encouraging. The data is still evolving. We remind all that the time course for STAR mRNA technology is extended and different from conventional messenger RNA, which is one of the reasons why we're seeing activity at such low dose levels. The data that we've collected will be published at the time of study completion. We believe that ARCTO21 could be an important addition in the global fight against COVID-19. We look forward to advancing ARCTO21 into later stage clinical studies as quickly as possible. In parallel with our clinical development activities, we've also made progress with our manufacturing activities of our vaccine. With the support of Catalan and Resafarm and other manufacturing partners, Arcturus remains on track to manufacture substantial numbers of doses. Arcturus announced earlier today an agreement with the Singapore Economic Development Board to support our manufacturing efforts. And Andy is going to be providing more details on that in a few minutes. In August, we signed a binding term sheet with the Israeli Ministry of Health to supply ARCTO21. We consider this a core or an important part of the country's vaccination strategy. Israel is the second country in addition to Singapore to reserve supply of Arcturus' COVID-19 vaccine. And we also continue to have constructive discussions with additional countries pertaining to stockpiling and supply agreements. Now shifting focus to ARCT 810 for OTC deficiency. We continue to make great progress with our lunar OTC programs. We've completed dose escalation of all cohorts, 0.1, 0.2, 0.3, and now including the top dose of 0.4 milligrams per kilogram in our Phase I study. We're pleased to report that steroid pretreatment was not necessary, even for the top dose cohort. And we've commenced enrollment of a Phase Ib study here in the United States in OTC-deficient patients, and our first subject is initiated screening. So there's a lot there to report in one quarter for Arcturus. And I now pass the call to Steve to review and provide more detail pertaining to the ARCTO21 Phase 1-2 study results, as well as new Phase 1 data from our ARCT810 Ornithine Transcarbamylase Deficiency Program.