HCV core

-- International Herpesvirus Workshop will feature oral and poster presentations of preclinical data from ABI-5366, Assembly Bio’s first herpesvirus development candidate -- -- Five posters accepted for presentation at EASL 2023 highlight the latest data from pipeline in hepatitis B and hepatitis D viruses -- SOUTH SAN FRANCISCO, Calif., June 07, 2023 (GLOBE NEWSWIRE) -- Assembly Biosciences, Inc. (Nasdaq: ASMB), a biotechnology company developing innovative antiviral therapeutics targeting serious viral diseases, today announced that the company will present data from its herpes simplex virus (HSV), hepatitis D virus (HDV) and hepatitis B virus (HBV) pipeline programs at upcoming medical congresses. Assembly Bio’s abstract for ABI-5366 has been accepted for oral and poster presentation at the International Herpesvirus Workshop, taking place in Missoula, Montana, July 15-19, 2023. Five abstracts have been accepted for poster presentation at the International Liver Congress™, the Annual Meeting of the European Association for the Study of the Liver (EASL) taking place in Vienna, Austria, June 21-24, 2023, including one poster presentation selected for inclusion in the Best of EASL Congress summary. International Herpesvirus Workshop 2023For the first time, Assembly Bio will present data highlighting the preclinical characterization of ABI-5366, a long-acting HSV helicase inhibitor targeting high-recurrence genital herpes and the company’s first development candidate for herpesviruses. “We are excited to present these data describing ABI-5366’s compelling preclinical profile, including low nanomolar potency in vitro against both HSV-1 and HSV-2, the potential for long-acting oral administration and non-GLP safety data to date showing that the candidate has been well tolerated,” said William Delaney, PhD, chief scientific officer of Assembly Bio. “High-recurrence genital herpes remains an important unmet need that has not had a significant therapeutic advancement in decades. We continue to actively progress our IND-enabling studies, with initiation of GLP toxicity studies targeted for early Q3 2023, and we expect to enter the clinic in the first half of next year.” Details of the presentations are as follows: ABI-5366: Oral and Poster Presentation: Pre-clinical characterization of ABI-5366: a highly potent long-acting helicase-primase inhibitor for the treatment of high-recurrence genital herpesPresenter: Heidi Contreras, PhD, Assembly BioOral Session Date and Time: 4C – Immunity and Vaccines, July 19 at 11:00 AM MDTPoster Session Date and Time: Not Yet Available EASL International Liver Congress™ 2023At EASL, Assembly Bio will present new preclinical data from its novel small molecule HBV and HDV oral entry inhibitors supporting advancement of the program towards a candidate nomination. The EASL presentations also include the first conference presentations of data from two clinical studies of the company’s highly potent, next-generation HBV core inhibitors, the Phase 1a study of ABI-4334, Assembly Bio’s most potent core inhibitor with the potential for a best-in-class profile, and the Phase 1b study of ABI-H3733 in patients with chronic HBV infection. The latter poster was selected for inclusion in the Best of EASL Congress summary and a Session Poster Tour. “We are also looking forward to sharing the latest data from our HBV and HDV pipeline at EASL’s annual International Liver Congress,” continued Dr. Delaney. “These data highlight the promise of our small molecule HBV/HDV entry program, from which we anticipate nominating a development candidate this year, and reinforce the potential of next-generation core inhibitors in efforts to achieve HBV cure.” Details of poster presentations are as follows: Small-Molecule HBV/HDV Viral Entry Inhibitor: Poster SAT-195: A novel class of orally-available small molecules potently inhibiting hepatitis B and D virus entryPresenter: Marc P. Windisch, PhD, Assembly BioSession: Viral Hepatitis B and D: New therapies, unapproved therapies or strategiesDate and Time: June 24 at 9:00 AM CEST Next-Generation Core Inhibitors: Poster SAT-168: Safety, pharmacokinetics, and antiviral activity of the next-generation hepatitis B core inhibitor ABI-H3733 in patients with hepatitis B e antigen negative chronic hepatitis B infection: preliminary results from a randomized, blinded, Phase 1b studyPresenter: Edward J. Gane, MBCHB, MD, FRACP, MNZM, University of Auckland, Auckland, New ZealandSession: Viral Hepatitis B and D: New therapies, unapproved therapies or strategiesDate and Time: June 24 at 9:00 AM CESTSession Poster Tour: June 23 at 16:15 PM CEST, at the Viral Hepatitis track hub Poster SAT-186: The safety and pharmacokinetics of ABI-4334, a novel next-generation HBV core inhibitor: interim results from a phase 1 study in healthy volunteersPresenter: Edward J. Gane, MBCHB, MD, FRACP, MNZM, University of Auckland, Auckland, New ZealandSession: Viral Hepatitis B and D: New therapies, unapproved therapies or strategiesDate and Time: June 24 at 9:00 AM CEST Poster WED-114: Next generation core inhibitors ABI-H3733 and ABI-4334 have significantly improved potency and target coverage for both antiviral and cccDNA formation activities compared to first-generation core inhibitorsPresenter: Kathryn M. Kitrinos, PhD, Assembly BioSession: Viral Hepatitis B and D: Clinical aspectsDate and Time: June 21 at 9:00 AM CEST Vebicorvir: Poster SAT-174: Vebicorvir, entecavir, and pegylated interferon in patients with hepatitis B e antigen positive chronic hepatitis B virus infection: findings from a phase 2, randomized open-label study in ChinaPresenter: Grace Wang, MD, Assembly BioSession: Viral Hepatitis B and D: New therapies, unapproved therapies or strategiesDate and Time: June 24 at 9:00 AM CEST About Assembly BiosciencesAssembly Biosciences is a biotechnology company dedicated to the development of innovative small molecule antiviral therapeutics designed to change the path of serious viral diseases and improve the lives of patients worldwide. Led by an accomplished team of leaders in virologic drug development, Assembly Bio is committed to improving outcomes for patients struggling with the serious, chronic impacts of herpesvirus, hepatitis B virus (HBV) and hepatitis delta virus (HDV) infections. For more information, visit assemblybio.com. Forward-Looking StatementsThe information in this press release contains forward-looking statements that are subject to certain risks and uncertainties that could cause actual results to materially differ. These risks and uncertainties include: Assembly Bio’s ability to maintain financial resources necessary to continue its clinical studies and fund business operations; Assembly Bio’s ability to initiate and complete clinical studies involving its therapeutic product candidates, including studies contemplated by Assembly Bio’s collaboration agreements, in the currently anticipated timeframes; safety and efficacy data from clinical or nonclinical studies may not warrant further development of Assembly Bio’s product candidates; clinical and nonclinical data presented at conferences may not differentiate Assembly Bio’s product candidates from other companies’ candidates; results of nonclinical studies may not be representative of disease behavior in a clinical setting and may not be predictive of the outcomes of clinical studies; and other risks identified from time to time in Assembly Bio’s reports filed with the U.S. Securities and Exchange Commission (the SEC). You are urged to consider statements that include the words may, will, would, could, should, might, believes, hopes, estimates, projects, potential, expects, plans, anticipates, intends, continues, forecast, designed, goal or the negative of those words or other comparable words to be uncertain and forward-looking. Assembly Bio intends such forward-looking statements to be covered by the safe harbor provisions contained in Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. More information about Assembly Bio’s risks and uncertainties are more fully detailed under the heading “Risk Factors” in Assembly Bio’s filings with the SEC, including its most recent Annual Report on Form 10-K, Quarterly Reports on Form 10-Q and Current Reports on Form 8-K. Except as required by law, Assembly Bio assumes no obligation to update publicly any forward-looking statements, whether as a result of new information, future events or otherwise. Contacts Investor and Corporate:Shannon RyanSVP, Investor Relations, Corporate Affairs and Alliance Management(415) 738-2992sryan@assemblybio.com Media:Sam Brown Inc. Hannah Hurdle (805) 338-4752 ASMBMedia@sambrown.com

Assembly Biosciences paused work on its hepatitis B virus core inhibitor after seeing “a time-dependent toxicity in one species.” Biotech’s back burner is getting even busier. The latest set of earnings reports brought news of more drug programs that are being stopped or deprioritized, with Assembly Biosciences, Context Therapeutics and Innate Pharma all rethinking where to allocate their R&D budgets. Antiviral startup Assembly paused development of one of its hepatitis B virus core inhibitors, ABI-H3733, after going over the early-phase data on it and another similar molecule. The biotech narrowed its focus based on phase 1 data on both candidates and a chronic toxicology observation for ABI-H3733. In the 26-week nonclinical toxicology study, Assembly saw “a time-dependent toxicity in one species.” The toxicity was not seen in an earlier 28-day nonclinical study and may be a surmountable problem. But given the expectation that an additional chronic toxicology study in another species would be needed to take ABI-H3733 into phase 2, the biotech has paused work rather than incur the extra costs.  Assembly ended 2022 with $91.6 million in the bank, a sum it forecasts will keep it going into the middle of next year. The biotech plans to report additional phase 1a data on its other core inhibitor, ABI-4334, next month and complete a filing to run a clinical trial of another asset, herpesvirus candidate ABI-5366, in the first half of next year. The R&D rethink at Context was triggered by new data too. In an ongoing phase 2 trial of onapristone extended release in endometrial cancer, elevated liver function tests were seen in three patients, one of whom discontinued treatment.  None of the liver test results were classed as serious adverse events but the biotech concluded that the need to analyze and mitigate future abnormalities will cause “significant incremental program costs and delays.” With $35.5 million to its name, Context isn’t in a position to weather such costs and delays. The biotech will now focus on a CLDN6 bispecific antibody, for which a clinical trial filing is planned for early next year. Finally, Innate is stopping the development of anti-C5aR1 antibody avdoralimab in the rare skin condition bullous pemphigoid. The French drug developer took the candidate into the clinic as a solid tumor drug in 2018, working with AstraZeneca to test it in combination with a checkpoint inhibitor, but stopped the trial early. An attempt to reposition the molecule as a treatment for COVID-19 ended in failure.  Throughout the changes, investigators at French hospitals continued to study the candidate in bullous pemphigoid, attracted by evidence that the C5aR1 pathway is strongly involved in the disease. However, Innate has now called time on the program, revealing it is discontinuing development in the indication and evaluating out-licensing as a potential next step.