 Phase 1a1b clinical trial for AB-729, a subcutaneously delivered RNAi agent, remains on track with results from additional cohorts expected in the second half of 2020 AB-836, an oral capsid inhibitor, remains on track for completion of IND enabling studies by the end of 2020Actively screening multiple new molecular entities in recently initiated COVID-19 research programCash runway guidance extended into mid-2022 Conference Call and Webcast Scheduled Today at 8:45 AM ETWARMER, Pa., Aug. 07, 2020 GLOBE NEWSWIRE -- Arbutus Biopharma Corporation Nasdaq: ABUS, a clinical-stage biopharmaceutical company primarily focused on developing a cure for people with chronic hepatitis B virus HBV infection, as well as therapies to treat coronaviruses including COVID-19, today reports its second quarter 2020 financial results and provides a corporate update.William Collier, President and Chief Executive Officer of Arbutus, stated, Despite the challenging conditions resulting from the COVID-19 pandemic, we continue to make steady progress in our Phase 1a1b clinical trial of AB-729, a subcutaneously delivered RNAi agent, and have recently initiated an additional AB-729 90 mg single-dose cohort in HBV DNA positive subjects. We also intend to initiate two 90 mg multi-dose cohorts in the second half of this year.Mr. Collier added, Importantly, in March and May of this year we announced positive preliminary results from this trial, and we look forward to providing additional clinical updates in the second half of 2020. We anticipate these updates will include data from 60 mg multi-dose cohorts with dosing intervals every four and eight weeks and 90 mg single-dose week 12 data in HBV DNA negative and positive subjects. We continue to believe AB-729 is a potent RNAi agent capable of reducing HBsAg plasma levels.Pipeline UpdateAB-729 AB-729 is an RNA interference RNAi therapeutic targeted to hepatocytes using Arbutus novel covalently conjugated N-acetylgalactosamine GalNAc delivery technology that enables subcutaneous delivery. AB-729 inhibits viral replication and reduces all HBV antigens, including hepatitis B surface antigen HBsAg, in preclinical models. Reducing HBsAg is thought to be essential to enable the reawakening of a patients immune system so that it can respond to the virus. Arbutus is currently conducting a single- and multi-dose Phase 1a1b clinical trial to determine the safety, tolerability, pharmacokinetics, and pharmacodynamics of AB-729 in healthy subjects and in subjects with chronic HBV infection. Preliminary positive safety data in single-dose cohorts of healthy subjects and safety and efficacy data in the 60 mg and 180 mg single-dose cohorts in subjects with chronic HBV infection were reported in March 2020. Additional follow-on week 12 data for the 60 mg single-dose cohort were reported in May 2020. The data demonstrate the robust activity of AB-729 and, at week 12, the 60 mg single-dose achieved equivalent reductions in HBsAg as the 180 mg single-dose and did so while remaining generally safe and well tolerated with no abnormal transaminase values in any of the six subjects. Mean HBsAg changes from baseline: 60 mg Single-Dose Cohort N6180 mg Single-Dose Cohort N4 Day 29 mean log10 IUmL Standard Error of the Mean-0.24 0.13-0.8 0.38 Week 12 day 84 mean log10 IUmL Standard Error of the Mean-0.99 0.24-0.98 0.22 Arbutus is dosing two 60 mg multi-dose cohorts of subjects with chronic HBV infection with dosing intervals of every four and eight weeks, respectively. Arbutus is also dosing subjects in a 90 mg single-dose cohort. Results from these cohorts are expected in the second half of 2020. We also intend to initiate two 90 mg multi-dose cohorts in the second half of this year. Arbutus has also initiated an additional AB-729 90 mg single-dose cohort in HBV DNA positive subjects with results expected in the second half of 2020.AB-836: Oral Capsid Inhibitor AB-836 is an oral HBV capsid inhibitor. HBV core protein assembles into a capsid structure, which is required for viral replication. The current standard-of-care therapy for HBV, primarily nucleostide analogues that work by inhibiting the viral polymerase, significantly reduce virus replication, but not completely. Capsid inhibitors inhibit replication by preventing the assembly of functional viral capsids. They also have been shown to inhibit the uncoating step of the viral life cycle thus reducing the formation of new covalently closed circular DNA cccDNA, the genetic reservoir which the virus uses to replicate itself. In January 2020, Arbutus selected AB-836 as its next-generation oral capsid inhibitor. AB-836 is from a novel chemical series differentiated from Arbutus second generation capsid inhibitor candidate, AB-506, as well as competitor compounds. AB-836 has the potential for increased potency and an enhanced resistance profile as compared to AB-506. Arbutus continues to expect completion of IND-enabling studies by the end of 2020.Early HBV RD Programs Arbutus drug discovery efforts are focused on follow-on compounds for its current HBV pipeline, including the development of oral RNA-destabilizers that have shown compelling antiviral effects in multiple HBV preclinical models. Arbutus is now focused on advancing next-generation oral RNA-destabilizers with chemical scaffolds distinct from Arbutus prior generation HBV RNA destabilizer candidate, AB-452, through lead optimization. Arbutus also has several oral anti-PD-L1 inhibitors in lead optimization that are potentially capable of reawakening the immune response to HBV in infected patients.Research Efforts to Combat COVID-19 and Future Coronavirus Outbreaks Earlier this year, the Company initiated an internal research program to identify new small molecule antiviral medicines to treat COVID-19 and future coronavirus outbreaks. Dr. Michael Sofia, Arbutus Chief Scientific Officer, who was awarded the Lasker-DeBakey Award for his discovery of sofosbuvir, brings extensive antiviral drug discovery experience to this new program. Arbutus has also joined forces with the COVID RD consortium to further support and expedite efforts to address the COVID-19 pandemic. At this time, Arbutus COVID-19 research program will focus on the discovery and development of new molecular entities that address specific viral targets including the nsp12 viral polymerase and the viral protease. These targets are essential viral proteins which Arbutus has experience in targeting. The Company is actively screening multiple new oral molecular entities. The establishment of the COVID-19 effort does not impact Arbutus current cash burn guidance for 2020 of 54 to 58 million.Genevant Sciences Ltd. Update On July 23, 2020, the United States Patent and Trademark Office before the Patent Trial and Appeal Board PTAB announced their decision in Moderna Therapeutics, Inc.s challenge of the validity of U.S. Patent 8,058,069 the 069 Patent. In this decision, the PTAB determined no challenged claims were unpatentable. While Arbutus is the patent holder, this patent has been licensed to Genevant. The 069 Patent was included in this license agreement between Genevant and Arbutus. Arbutus is gratified by the recent decision of the PTAB, upholding the validity of one of the patents protecting Arbutus LNP technology that Arbutus licensed to Genevant. This decision reinforces Arbutus continuing belief in the potential of this technology.Arbutus is entitled to receive tiered low single digit royalties on future sales of Genevant products covered by the licensed patents. If Genevant sub-licenses the intellectual property licensed by Arbutus to Genevant, Arbutus would receive upon the commercialization of a product developed by such sub-licensee the lesser of i twenty percent of the revenue received by Genevant for such sublicensing and ii tiered low single digit royalties on product sales by the sublicensee.On July 31, 2020, Roivant recapitalized Genevant through an equity investment and conversion of previously issued convertible debt securities held by Roivant. Arbutus participated in the recapitalization of Genevant with an equity investment of 2.5 million. Following the recapitalization, Arbutus owns approximately 16 of the common equity of Genevant. Arbutus entitlement to receive future royalties or sublicensing revenue from Genevant remains unchanged.COVID-19 ImpactIn December 2019 an outbreak of a novel strain of coronavirus COVID-19 was identified in Wuhan, China. This virus continues to spread globally, has been declared a pandemic by the World Health Organization and has spread to nearly every country in the world. The impact of this pandemic has been, and will likely continue to be, extensive in many aspects of society. The pandemic has resulted in and will likely continue to result in significant disruptions to businesses. A number of countries and other jurisdictions around the world have implemented extreme measures to try and slow the spread of the virus. These measures include the closing of businesses and requiring people to stay in their homes, the latter of which raises uncertainty regarding the ability to travel to hospitals in order to participate in clinical trials. Additional measures that have had, and will likely continue to have, a major impact on clinical development, at least in the near-term, include shortages and delays in the supply chain, and prohibitions in certain countries on enrolling subjects in new clinical trials. While we have been able to progress with our clinical and pre-clinical activities to date, it is not possible to predict if the COVID-19 pandemic will negatively impact our plans and timelines in the future. 