News

MENDHAM, N.J. and WARMINSTER, Pa., – Antios Therapeutics, Inc. and Arbutus Biopharma Corporation (Nasdaq: ABUS) today announced that the companies have entered into a clinical collaboration agreement to evaluate a triple combination of Arbutus’ proprietary GalNAc delivered RNAi therapeutic, AB-729, Antios’ proprietary active site polymerase inhibitor nucleotide (ASPIN), ATI-2173, and Viread (tenofovir disoproxil fumarate), for the treatment of subjects with chronic hepatitis B virus (HBV) infection.

ATI-2173, AB-729 and Viread will be evaluated in combination in a single cohort in the ongoing Antios Phase 2a ANTT201 clinical trial. The multi-center, double-blinded, placebo-controlled, multiple‑dose cohort will evaluate the safety, pharmacokinetics, immunogenicity, and antiviral activity of the combination of ATI-2173, AB-729 and Viread. This cohort is expected to initiate in the second half of 2021. Antios will be responsible for the costs of adding this single cohort to its ongoing clinical trial. Arbutus will be responsible for the manufacture and supply of AB-729.

“This collaboration with Antios advances our efforts to position AB-729 as a potential cornerstone therapeutic in future HBV combination regimens and reflects our conviction that a combination of agents with complementary mechanisms of action is needed to cure chronic HBV,” stated William Collier, Chief Executive Officer at Arbutus.”

Greg Mayes, Chief Executive Officer of Antios said, “ATI-2173 has, to date, demonstrated a well-tolerated safety profile and sustained on- and off-treatment antiviral responses as a monotherapy in patients with chronic HBV. We believe that its unique mechanism of action and early evidence of clinical activity may position ATI-2173 as the backbone of a once-daily curative regimen in combination with other agents for chronic HBV. Our collaboration with Arbutus will test that hypothesis in combination with AB-729, an RNAi drug candidate, and Viread, a nucleotide analogue.”

About the Combination Clinical Trial Cohort

The combination clinical trial cohort will include 10 subjects with chronic HBV infection assigned 8:2 to active drug (ATI-2173+AB-729) or matching placebos. The active drug (ATI-2173+AB-729) or placebo will be administered in combination with 300 mg of Viread (equivalent to 245 mg of tenofovir disoproxil fumarate). ATI-2173 and Viread will be administered once a day for 90 days. AB-729 will be administered by subcutaneous injection at Day 28 and Day 90. Following this 90 day treatment period, subjects will be followed-up for safety and sustained antiviral responses for 6 additional months.

Any subjects whose HBV DNA remains below the limit of quantification (BLQ) at 6 months of follow-up will have HBV DNA and virology samples collected every 3 months off therapy until a detectable HBV DNA level is confirmed, or until 18 months after the 6 months of follow-up, whichever comes first.

About AB-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 in preclinical models. Reducing hepatitis B surface antigen is thought to be a key prerequisite to enable reawakening of a patient’s immune system to respond to the virus. Based upon clinical data generated thus far in an ongoing single- and multi-dose Phase 1a/1b clinical trial, AB-729 has demonstrated positive safety and tolerability data and meaningful reductions in hepatitis B surface antigen.

About ATI-2173

ATI-2173 is a novel, orally-administered, liver-targeted Active Site Polymerase Inhibitor Nucleotide (ASPIN) molecule designed to deliver the 5’-monophosphate of clevudine to the liver. This L-nucleoside’s active 5’-triphosphate has unique antiviral properties as a non-competitive, non-chain terminating HBV polymerase inhibitor that distorts the active site of HBV polymerase resulting in potent HBV antiviral activity and extended off-treatment suppression of HBV DNA. ATI-2173 targets the liver, delivering high levels of the unique 5’- triphosphate while limiting systemic exposure to the parent L-nucleoside. ATI-2173 has the potential to become an integral part of a curative combination regimen for chronic hepatitis B.

About HBV

Hepatitis B is a potentially life-threatening liver infection caused by HBV. HBV can cause chronic infection which leads to a higher risk of death from cirrhosis and liver cancer. Chronic HBV infection (CHB) represents a significant unmet medical need. The World Health Organization estimates that over 250 million people worldwide suffer from chronic HBV infection, while other estimates indicate that approximately 2 million people in the United States suffer from chronic HBV infection. Approximately 900,000 people die every year from complications related to chronic HBV infection despite the availability of effective vaccines and current treatment options.

About Arbutus

Arbutus Biopharma Corporation is a publicly traded (Nasdaq: ABUS) biopharmaceutical company primarily focused on discovering, developing and commercializing a cure for people with chronic hepatitis B virus (HBV) infection. The Company is advancing multiple product candidates with distinct mechanisms of action that it believes have the potential to provide a new curative regimen for chronic HBV infection. Arbutus has also initiated a drug discovery and development effort for treating coronaviruses (including COVID-19). For more information, visit www.arbutusbio.com.

About Antios

Antios Therapeutics is a clinical-stage biopharmaceutical company focused on the development of innovative therapies to treat and cure viral diseases. Antios is currently developing ATI-2173, aiming to provide chronic hepatitis B-infected patients with a curative combination regimen.

Arbutus Forward-Looking Statements and Information

This press release contains forward-looking statements within the meaning of the Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934, and forward-looking information within the meaning of Canadian securities laws (collectively, “forward-looking statements”). Forward-looking statements in this press release include statements about our expectations for the collaboration; the timing and expected trial design of the Phase 2a clinical trial to be initiated by the parties pursuant to the agreement; and Arbutus’ belief that AB-729 has the potential to become a cornerstone therapeutic in multiple future HBV combination regimens.

With respect to the forward-looking statements contained in this press release, Arbutus has made numerous assumptions regarding, among other things: the effectiveness and timeliness of preclinical studies and clinical trials, and the usefulness of the data; the timeliness of regulatory approvals; the continued demand for Arbutus’ assets; and the stability of economic and market conditions. While Arbutus considers these assumptions to be reasonable, these assumptions are inherently subject to significant business, economic, competitive, market and social uncertainties and contingencies, including uncertainties and contingencies related to the ongoing COVID-19 pandemic.

Additionally, there are known and unknown risk factors which could cause Arbutus’ actual results, performance or achievements to be materially different from any future results, performance or achievements expressed or implied by the forward-looking statements contained herein. Known risk factors include, among others: the parties may never realize the expected benefits of the collaboration; anticipated clinical trials may be more costly or take longer to complete than anticipated, and may never be initiated or completed, or may not generate results that warrant future development of the candidate; Arbutus may elect to change its strategy regarding its product candidates and clinical development activities; economic and market conditions may worsen; market shifts may require a change in strategic focus; and the ongoing COVID-19 pandemic could significantly disrupt clinical development programs.

A more complete discussion of the risks and uncertainties facing Arbutus appears in Arbutus’ Annual Report on Form 10-K, Arbutus’ Quarterly Reports on Form 10-Q and Arbutus’ continuous and periodic disclosure filings, which are available at www.sedar.com and at www.sec.gov. All forward-looking statements herein are qualified in their entirety by this cautionary statement, and Arbutus disclaims any obligation to revise or update any such forward-looking statements or to publicly announce the result of any revisions to any of the forward-looking statements contained herein to reflect future results, events or developments, except as required by law.

Arbutus Contact Information

Investors and Media

William H. Collier
President and CEO
Phone: 267-469-0914
Email: [email protected]

Pam Murphy
Investor Relations Consultant
Phone: 267-469-0914
Email: [email protected]

Antios Contact Information

Investors:
Lee Roth
Burns McClellan
[email protected]
+1 (212) 300-8331

Media:
Ryo Imai / Robert Flamm, PhD
Burns McClellan
[email protected] / [email protected]
+1 (212) 300-8315 / +1 (212) 300-8364

 

Data to be presented at the EASL Digital International Liver Congress™ 2021

Two poster presentations and supporting slides are available at https://www.antiostherapeutics.com/scientific-approach/publications-presentations/

MENDHAM, NJ, June 23, 2021 — Antios Therapeutics, Inc. (“Antios”) today announced pharmacokinetic (PK), safety and efficacy data from a Phase 1b clinical trial of ATI-2173, the Company’s Active Site Polymerase Inhibitor Nucleotide (ASPIN), in chronic HBV-infected adult patients. The compelling results of the trial demonstrated low systemic levels of ATI-2173 consistent with preclinical evidence of selective liver targeting previously demonstrated in rat and monkey models. ATI-2173 was generally well tolerated and led to off-treatment sustained viral suppression in chronic HBV patients as monotherapy. The data will be presented as two posters at the European Association of Liver Diseases (EASL) Digital International Liver Congress™ 2021 being held virtually from June 23-26.

“Current treatments for chronic HBV infections generally must be life-long because cessation of therapy usually results in re-emergence of the virus,” said Douglas Mayers, M.D., Chief Medical Officer of Antios. “ATI-2173 is an investigational prodrug of clevudine, which historically demonstrated potent and sustained reductions in HBV viral load, but high plasma levels of clevudine were associated with a rare adverse reaction of reversible myopathy. Our hypothesis is that a compound with a similar mechanism of action in the liver, but minimal plasma exposure would potentially replicate clevudine’s antiviral activity without off-target systemic toxicity, and therefore could be positioned, if successful, as the backbone of a once-daily curative regimen for HBV infection.

“In this study, ATI-2173 was generally well-tolerated and successfully targeted the liver with greatly reduced systemic exposure of clevudine compared with historical clevudine data. ATI-2173 also demonstrated sustained off-treatment antiviral responses as a monotherapy. The results of this study strongly support our hypothesis. We are now evaluating 25 mg and 50 mg once-daily doses in combination with tenofovir for 3 months in a Phase 2a clinical trial in adult patients with either chronic HBV infection or chronic HBV/hepatitis D virus co-infection.”

Details of the presentations are below. Both posters can be found on the Antios website at https://www.antiostherapeutics.com/scientific-approach/publications-presentations/.

Title: Pharmacokinetics of ATI-2173, a novel active site polymerase inhibitor nucleoside, in a Phase 1b clinical trial
Authors: Katherine Squires et al.
Presenter: Katherine Squires, Ph.D.
Track: Viral hepatitis B/D: therapy
Abstract Number: 1240

Title: Phase 1 Results for ATI-2173, a novel active site polymerase inhibitor nucleotide, in HBV-infected subjects
Authors: Douglas Mayers et al.
Presenter: Douglas Mayers, M.D.
Track: Viral hepatitis B/D: therapy
Abstract Number: 1251

The Phase 1b clinical trial enrolled 24 chronic HBV patients (positive for HBV surface antigen (HBsAg)) who were randomized to receive either 10 mg (n=6), 25 mg (n=5), or 50 mg (n=6) of ATI-2173 or placebo (n=7) once-daily for 28 days. Safety analyses included monitoring for adverse events (AEs) and measuring several clinical laboratory parameters. PK analyses included a comparison of ATI-2173 and its metabolites (M1 and clevudine) with historically published PK parameters of clevudine. Antiviral activity was evaluated via several measures including HBV DNA, HBsAg, HBV pregenomic RNA (pgRNA) and HBV core-related antigen (HBcrAg) and were recorded periodically during the treatment period and for up to 24 weeks following cessation of treatment.

28-day treatment with ATI-2173 resulted in potent and sustained antiviral activity.

• HBV DNA showed a 2.7 log₁₀ copies/ml reduction for all three doses compared to placebo which showed no change in HBV DNA levels. This is comparable with the 2.5 to 3 log₁₀ reduction reported previously following one month of treatment with clevudine.
• At the end of the treatment period, 71% of treated patients - three of six subjects (10 mg arm), four of five subjects (25 mg arm) and five of six subjects (50 mg arm) - had HBV DNA levels below the limit of detection.
• Sustained viral response (SVR) post treatment was 100% (nine of nine subjects in the 25 and 50 mg groups) after four weeks off treatment and 44% (four of nine subjects) after 12 weeks off treatment. One patient maintained an SVR through 24 weeks off treatment.
• HBsAg levels did not change during the 28-day treatment period for any dose or placebo, which was expected due to the short treatment period.
• HBV pgRNA showed a mean decrease of 0.9 log₁₀ copies/ml with both 25 mg and 50 mg doses of ATI-2173 whereas placebo showed a mean increase of 0.6 log₁₀ copies/ml.
• HBcrAg showed a mean 0.2 log₁₀ copies/ml decrease following treatment with ATI-2173 whereas placebo showed a 0.4 log₁₀ copies/ml increase.
• ALT levels were normalized with all doses of ATI-2173 whereas ALT levels remained elevated in placebo patients.

ATI-2173 is designed to be highly targeted to the liver and was found to be generally well-tolerated across all treatment groups.

• ATI-2173 was rapidly absorbed following single doses with maximum plasma concentration measured at 0.5 hours post dose then declined rapidly to undetectable levels by eight hours post dose. Plasma clevudine remains detectible through 24 hours post-dose.
• Mean plasma ATI-2173 concentrations were dose proportional with no evidence of plasma accumulation following 28 days of dosing, whereas plasma clevudine concentrations showed higher total exposure on day 28.
• Standard PK measures show that oral ATI-2173 resulted in low plasma clevudine exposures compared to historical clevudine data (see table below), while retaining potent antiviral activity.

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Drug	Cmax, ng/mL	Cmin, ng/mL	AUC24, ng·h/mL
Historical clevudine 30 mg, mean5	203	56	2010
ATI-2173 10 mg, mean (% historical value)a	6 (3)	0	92 (5)
ATI-2173 25 mg, mean (% historical value)a	17 (8)	9 (15)	257 (13)
ATI-2173 50 mg, mean (% historical value)a	42 (20)	22 (40)	691 (34)
AUC24, 24-hour area under the plasma concentration-time curve; Cmax, maximum concentration; Cmin, minimum concentration; PK, pharmacokinetic. aPercent historical value was calculated by dividing the mean plasma clevudine PK parameter following 28 days of ATI-2173 administration by the mean plasma clevudine PK parameter reported following administration of clevudine 30 mg for 12 weeks.5 5. Lim et al. Aliment Pharmacol Ther. 2008;27:1282-1292.

• No ATI-2173 dose-related treatment-emergent AEs were reported with headache being the most common AE reported in both ATI-2173 and placebo groups.
• There were no reported Serious Adverse Events (SAEs) or AEs leading to study drug discontinuation.

About ATI-2173
ATI-2173 is a novel, orally administered, liver-targeted Active Site Polymerase Inhibitor Nucleotide (ASPIN) molecule designed to deliver the 5’-monophosphate of clevudine to the liver. This L-nucleoside’s active 5’-triphosphate has unique antiviral properties as a non-competitive, non-chain terminating HBV polymerase inhibitor that distorts the active site of HBV polymerase resulting in potent HBV antiviral activity and extended off-treatment suppression of HBV DNA. ATI-2173 targets the liver, delivering high levels of the unique 5’- triphosphate while limiting systemic exposure to the parent L-nucleoside. ATI-2173 has the potential to become an integral part of a curative combination regimen for chronic hepatitis B.

About Antios Therapeutics Inc.

Antios Therapeutics is a clinical-stage biopharmaceutical company focused on the development of innovative therapies to treat and cure viral diseases. Antios is currently developing ATI-2173, aiming to provide chronic hepatitis B infected patients with a curative combination regimen.

CONTACTS

Investors:
Lee Roth
Burns McClellan
[email protected]
+1 (212) 300-8331

Media:
Ryo Imai / Robert Flamm, Ph.D.
Burns McClellan
[email protected] / [email protected]
+1 (212) 300-8315 / +1 (212) 300-8364

 

HBV-TAG: Presentation of in vitro antiviral activity and Phase 1a healthy volunteer data demonstrating the safety, tolerability, and favorable pharmacokinetics of multiple ascending doses of ATI-2173

Pharmacokinetics, antiviral efficacy, and safety of ATI-2173 from a Phase 1b trial in chronic HBV-infected subjects will be presented for the first time at the European Society of Liver Diseases (EASL) International Liver Congress™ 2021 on June 23

MENDHAM, NJ, June 11, 2021 (GLOBE NEWSWIRE) – Antios Therapeutics, Inc. (“Antios”) today announced that the Company is presenting in vitro and Phase 1a data on ATI-2173, a liver targeting Active Site Polymerase Inhibitor Nucleotide (ASPIN) in clinical development as a component of a potentially curative regimen for chronic hepatitis B (HBV) infection, at the 2021 HBV-TAG (Hepatitis B -Therapeutic Agents) Conference, being held virtually on June 11 to 12.

Details of the poster presentation at HBV-TAG are as follows:

Title: ATI-2173, a novel active site polymerase inhibitor nucleotide (ASPIN) for HBV cure regimens, is well tolerated and has favorable pharmacokinetics in healthy volunteers

Authors: Mayers, D., et al.
The poster and accompanying slide presentation can be found on the Antios website at antiostherapeutics.com/publications.

In the study, the antiviral activity and resistance of ATI-2173 alone and in combination with nucleos(t)ide analogues, interferon, and a capsid inhibitor were evaluated, in vitro, in liver cell lines and primary human hepatocytes. Systemic and hepatic concentrations of both clevudine and its phosphoramidate prodrug, ATI-2173, were evaluated in two animal models. ATI-2173 demonstrated potent antiviral activity in vitro as a monotherapy, and additive or synergistic activity with traditional nucleos(t)ides and other direct-acting antivirals. ATI-2173’s ability to selectively target the liver while minimizing systemic exposure was demonstrated in both animal models when compared to the high systemic exposure of clevudine. Safety, tolerability and pharmacokinetics (PK) were evaluated in a Phase 1 clinical trial in healthy volunteers. In healthy human subjects, ATI-2173 was well tolerated with headache being the most common adverse event. The PK profile was dose-proportional with Cmax well-below the Cmin reported with clevudine administration at the marketed 30 mg dose.

Pharmacokinetics, antiviral efficacy, and safety of ATI-2173 from a Phase 1b trial in chronic HBV-infected subjects will be presented for the first time at the upcoming European Society of Liver Diseases (EASL) International Liver Congress™ 2021 to be held virtually on June 23.

About ATI-2173

ATI-2173 is a novel, orally-administered, liver-targeted Active Site Polymerase Inhibitor Nucleotide (ASPIN) molecule designed to deliver the 5’-monophosphate of clevudine to the liver. This L-nucleoside’s active 5’-triphosphate has unique antiviral properties as a non-competitive, non-chain terminating HBV polymerase inhibitor that distorts the active site of HBV polymerase resulting in potent HBV antiviral activity and extended off-treatment suppression of HBV DNA. ATI-2173 targets the liver, delivering high levels of the unique 5’- triphosphate while limiting systemic exposure to the parent L-nucleoside. ATI-2173 has the potential to become an integral part of a curative combination regimen for chronic hepatitis B.

About Antios Therapeutics Inc.

Antios Therapeutics is a clinical-stage biopharmaceutical company focused on the development of innovative therapies to treat and cure viral diseases. Antios is currently developing ATI-2173, aiming to provide chronic hepatitis B-infected patients with a curative combination regimen.

CONTACTS

Investors:
Lee Roth
Burns McClellan

[email protected]
+1 (212) 300-8331

Media:

Ryo Imai / Robert Flamm, PhD
Burns McClellan

[email protected] / [email protected]
+1 (212) 300-8315 / +1 (212) 300-8364

Responsible for managing clinical development and the regulatory processes for ATI-2173, an ASPIN, which is in development as part of a potential curative regimen for chronic hepatitis B infection

MENDHAM, N.J., April 27, 2021 (GLOBE NEWSWIRE) – Antios Therapeutics, Inc. (“Antios”) today announced the appointments of two experienced drug development executives, Katie Laessig, M.D., as Senior Vice President, Global Regulatory Affairs, and Karen Fusaro as Senior Vice President, Clinical Operations. These appointments add significant depth to the Company’s drug development team, which is focused on the clinical development of ATI-2173, an Active Site Polymerase Inhibitor Nucleotide (ASPIN), for the treatment of patients with chronic hepatitis B virus (HBV) infection. Both will report to Douglas Mayers, M.D., Chief Medical Officer of Antios.

“With the completion of our Phase 1b clinical trial of ATI-2173 in chronic HBV-infected patients, the recent initiation of SAVE-1 and expected late-stage clinical trials in coming years, we have been looking to add further clinical and regulatory expertise to our drug development team,” said Gregory Mayes, Chief Executive Officer of Antios. “Karen and Katie bring extensive experience in leading clinical operations and managing regulatory processes. We welcome both to the Antios leadership team.”

Dr. Laessig has more than 20 years of experience in pharmaceutical regulatory roles both in industry and for the U.S. FDA. Before joining Antios, she served as Vice President, Therapeutic Strategy, Strategic Drug Development at IQVIA where she delivered strategic regulatory and clinical development planning for pharmaceuticals and biologics, including support for regulatory interactions, across a range of therapeutic areas for the IQVIA’s biotechnology and pharmaceutical customers. Before that, she was SVP, Regulatory Affairs, Medical Safety and Quality Assurance at RRD International, LLC, where she provided strategic and tactical regulatory, clinical, and development evaluation and direction to product development programs undertaken by RRD for its client companies. From 1999 to 2015, Dr. Laessig served in multiple roles of increasing responsibility at the U.S. FDA including Medical Review Officer and Medical Team Leader, Division of Antiviral Products, and Deputy Director, Division of Anti-Infective Products. From 2000-2016, she volunteered once weekly at the Whitman Walker Clinic in Washington, DC, the city’s largest provider of HIV/AIDS care. Dr.Laessig earned her M.D. from the University of Maryland School of Medicine and a B.A. in Biology from Cornell University.

“From my years of clinical experience, and time at FDA and consulting with biopharmaceutical clients, I have witnessed both the critical need of patients suffering from viral diseases as well as the industry response through drug development and how regulators evaluate these potential therapies,” said Dr. Laessig. “Joining Antios is a great opportunity for me to leverage my expertise to guide ATI-2173 through the regulatory process toward eventual approval.”

Ms. Fusaro spent more than 20 years managing and leading execution of clinical trials from Phase 1 through Phase 3 in several therapeutic areas including infectious disease. Prior to joining Antios, she held several positions of increasing responsibility at Melinta Therapeutics where she oversaw all clinical, regulatory and pharmacovigilance activities for four antibiotic programs. Before that, she was responsible for clinical operations and clinical project management at The Medicines Company and contributed to the U.S. Food and Drug Administration (FDA) approvals of two antibiotics, ORBACTIV® and VABOMERE®. Additional experience included managing global clinical development of diabetes and cardiovascular programs at Novartis and managing global clinical trials for neuropathic pain, HIV, liver fibrosis and migraine candidates for GlaxoSmithKline. Ms. Fusaro earned a B.A. in Psychology from State University of New York at Binghamton.

“Antios is developing a drug candidate that could change the paradigm for treating patients with chronic HBV infection,” said Ms. Fusaro. “I look forward to working with the team to design and execute a clinical program that both optimizes trial success and supports the objective of developing a curative regimen for chronic HBV.”

About ATI-2173

ATI-2173 is a novel, orally administered, liver-targeted Active Site Polymerase Inhibitor Nucleotide (ASPIN) molecule designed to deliver the 5’-monophosphate of clevudine to the liver where it is metabolized to the active 5’-triphosphate. This L-nucleoside’s active 5’-triphosphate has unique antiviral properties as a non-competitive, non-chain terminating HBV polymerase inhibitor that distorts the active site of HBV polymerase resulting in potent HBV antiviral activity and extended off-treatment suppression of HBV DNA. ATI-2173 targets the liver, delivering high levels of the unique 5’- triphosphate while limiting systemic exposure to the parent L-nucleoside. ATI-2173 has the potential to become an integral part of a curative combination regimen for chronic hepatitis B.

About Antios Therapeutics Inc.

Antios Therapeutics is a clinical-stage biopharmaceutical company focused on the development of innovative therapies to treat and cure viral diseases. Antios is currently developing ATI-2173, aiming to provide chronic hepatitis B infected patients with a curative combination regimen.

SAVE 1 to evaluate ATI-2173 in combination with tenofovir (TDF) vs. TDF plus placebo
SAVE 1 to include cohort of Hepatitis Delta Virus (HDV) co-infected subjects to assess ATI-2173 activity against HDV

MENDHAM, N.J., April 21, 2021 (GLOBE NEWSWIRE) – Antios Therapeutics, Inc. (“Antios”) today announced that it has dosed the first patients in its Sustained Anti-Viral Efficacy (SAVE) clinical trial, a Phase 2a study of ATI-2173, an Active Site Polymerase Inhibitor Nucleotide (ASPIN) in clinical development as a backbone of a potentially curative regimen for chronic HBV.

The double-blind randomized controlled trial plans to enroll 30 patients and will assess the safety and efficacy of 25mg and 50mg doses of ATI-2173 in combination with tenofovir (TDF) compared with TDF plus ATI-placebo (control) in chronic HBV-infected subjects. A third cohort will evaluate 50mg of ATI-2173 and TDF against the control arm in HBV/HDV co-infected subjects. Efficacy will be assessed by both on-treatment maximum HBV DNA level responses and by off-treatment sustained virologic responses (SVR)s for the treatment arms in HBV-mono-infected subjects and by HDV RNA treatment responses in the HBV/HDV-coinfected subjects.

Following a screening period of up to eight weeks, subjects will be randomized to receive either once-daily, oral ATI-2173 plus TDF arm or control for 12 weeks, after which they will be evaluated off therapy during a 24-week follow-up period. Subjects’ HBV DNA will be measured regularly during both the treatment and follow-up periods. Subjects whose HBV DNA remains undetectable at six months post-treatment will be followed for up to an additional 18 months. Additional details of the clinical trial are available on clinicaltrials.gov (NCT04847440).

“We saw evidence of durable on- and off-treatment viral suppression in the Phase 1b study where ATI-2173 monotherapy was given for only 28 days,” said Gregory Mayes, chief executive officer of Antios. “We believe that the unique ability of ATI-2173 to inhibit all stages of HBV DNA synthesis could generate additional SVRs following three months of finite treatment in combination with the standard of care, TDF, potentially turning HBV from a chronic disease to a curable one for some patients.”

Douglas Mayers, chief medical officer of Antios added, “In addition to determining the ability of ATI-2173 to generate increased levels of SVR, this will be an extremely important study, as it may also provide proof-of-concept for the drug to be used as a treatment for HDV. Preclinical work in woodchuck models of HBV/HDV coinfection has demonstrated the ability of ATI-2173’s active metabolite to significantly reduce HDV RNA levels. This would be a tremendously promising finding if replicated in humans, as effective treatment of HDV remains a high unmet need. We anticipate completing dosing for SAVE 1 before the end of 2021 and presenting the results at a future scientific conference.”

About ATI-2173

ATI-2173 is a novel, orally administered, liver-targeted Active Site Polymerase Inhibitor Nucleotide (ASPIN) molecule designed to deliver the 5’-monophosphate of clevudine to the liver where it is metabolized to the active 5’-triphosphate. This L-nucleoside’s active 5’-triphosphate has unique antiviral properties as a non-competitive, non-chain terminating HBV polymerase inhibitor that distorts the active site of HBV polymerase resulting in potent HBV antiviral activity and extended off-treatment suppression of HBV DNA. ATI-2173 targets the liver, delivering high levels of the unique 5’- triphosphate while limiting systemic exposure to the parent L-nucleoside. ATI-2173 has the potential to become an integral part of a curative combination regimen for chronic hepatitis B.

About Antios Therapeutics Inc.

Antios Therapeutics is a clinical-stage biopharmaceutical company focused on the development of innovative therapies to treat and cure viral diseases. Antios is currently developing ATI-2173, aiming to provide chronic hepatitis B infected patients with a curative combination regimen.

Funding will support the Phase 2 clinical program of ATI-2173 in HBV

Soleus Capital led the round with new major investors RA Capital Management, Adage Capital Management LP, Pontifax and Aisling Capital as well as Altium Capital, Amzak Health, Granite Point Capital Management, LP, and Life Sci Venture Partners and participating existing investors Lumira Ventures, Cam Capital, Delos Capital, Domain Associates and Sixty Degree Capital

MENDHAM, N.J., April 12, 2021 (GLOBE NEWSWIRE) – Antios Therapeutics, Inc. (“Antios”) today announced the successful completion of a $96 million Series B financing. The proceeds from this financing will support the ongoing Phase 2 clinical program which is evaluating the potential for the Company’s lead clinical candidate, ATI-2173, to be a backbone of a once-daily curative regimen for chronic hepatitis B. ATI-2173 is a novel, orally administered, liver-targeted Active Site Polymerase Inhibitor Nucleotide (ASPIN) that can shut down HBV polymerase activity and viral replication.

The financing was led by Soleus Capital with participation from new major investors RA Capital Management, Adage Capital Management LP, Pontifax and Aisling Capital as well as other healthcare focused funds, Altium Capital, Amzak Health, Granite Point Capital Management, LP, and LifeSci Venture Partners and participation from all of the original Series A investors including Lumira Ventures, CAM Capital, Delos Capital, Domain Associates and Sixty Degree Capital. David Canner, Partner at Soleus Capital and Iyona Rajkomar, MBBS, CFA, Partner at Pontifax, are joining the Board of Directors.

“ATI-2173 has already demonstrated potent on-treatment and durable off-treatment effects in our Phase 1b study in patients with chronic hepatitis B,” said Greg Mayes, Chief Executive Officer of Antios. “Those results will be presented at an upcoming major medical conference. With this financing we are now well positioned to continue to highlight how ATI-2173 may become the backbone of a curative regimen for HBV which remains a significant unmet global public health need. We look forward to working with new and existing investors to advance ATI-2173 forward in development.”

Guy Levy, Chief Investment Officer of Soleus Capital said, “Despite significant progress in recent years, HBV remains an area of high unmet medical need. Given the mechanistic rationale and impressive early data, we believe ATI-2173 could play an essential role in developing curative regimens for the millions of people suffering from chronic HBV infection. We are excited to partner with the experienced team at Antios to help bring this therapy to patients.”

About ATI-2173

ATI-2173 is a novel, orally administered, liver-targeted Active Site Polymerase Inhibitor Nucleotide (ASPIN) molecule designed to deliver the 5’-monophosphate of clevudine to the liver. This L-nucleoside’s active 5’-triphosphate has unique antiviral properties as a non-competitive, non-chain terminating HBV polymerase inhibitor that distorts the active site of HBV polymerase resulting in potent HBV antiviral activity and extended off-treatment suppression of HBV DNA. ATI-2173 targets the liver, delivering high levels of the unique 5’- triphosphate while limiting systemic exposure to the parent L-nucleoside. ATI-2173 has the potential to become an integral part of a curative combination regimen for chronic hepatitis B.

About Antios Therapeutics Inc.

Antios Therapeutics is a clinical-stage biopharmaceutical company focused on the development of innovative therapies to treat and cure viral diseases. Antios is currently developing ATI-2173, aiming to provide chronic hepatitis B infected patients with a curative combination regimen.

ATLANTA, GA, Feb. 17, 2021 (GLOBE NEWSWIRE) – Antios Therapeutics, Inc. (“Antios”) today announced the appointment of seasoned financial executive, Tamra J. Adams, as the Company’s chief financial officer (CFO) effective March 1, 2021. Ms. Adams fills a newly created executive position at Antios as part of the Company’s rapid development.

“We have recently completed a Phase 1b clinical trial of our lead asset, ATI-2173, a potential backbone treatment in a functional curative regimen for chronic HBV infection, and anticipate presenting proof-of-concept data from the study in mid-2021,” said Gregory Mayes, chief executive officer of Antios. “We also look forward to aggressively moving the program into Phase 2 which will commence next month. For that reason, adding a senior financial executive experienced with emerging growth companies, including in biopharmaceuticals, to the executive management team is a critical step at this time. Tamra and I worked closely together at Engage Therapeutics for three years and I look forward to collaborating with her again as we continue to rapidly advance the development of ATI-2173 and evolve as a company.”

Ms. Adams has more than 25 years of experience in accounting and financial management. Before joining Antios, she founded Accounting Concepts, Inc., a firm that provided CFO, accounting, and financial services to emerging growth companies in the biopharmaceutical and information technology industries, including Engage Therapeutics, a company that was sold to UCB in 2020. Before that, Ms. Adams was a senior financial executive at Silverstorm Technologies, Inc., where she was responsible for financial and human resources functions and participated in an acquisition of the company by QLogic. Prior, she was the Controller of Starcite, Inc., an internet company, where she was responsible for financial reporting, business model development and internal control systems. Ms. Adams began her career at Ernst & Young, LLP, as a Senior Auditor specializing in entrepreneurial services and later at Goldman Sachs as a Senior Accounting Officer. Ms. Adams earned her B.S. in Accounting at State University of New York, Albany and is a certified public accountant in New York.

“I have spent the majority of my career managing the financial infrastructure for emerging growth companies and working with Antios gives me the opportunity to continue building upon that work,” said Ms. Adams. “The company is on a rapid growth trajectory and has the potential to make a significant contribution to public health. I look forward to helping build Antios into a leading biopharmaceutical company with the rest of the team.”

About ATI-2173

ATI-2173 is a novel, orally-administered, liver-targeted Active Site Polymerase Inhibitor Nucleotide (ASPIN) molecule designed to deliver the 5’-monophosphate of clevudine to the liver. This L-nucleoside’s active 5’-triphosphate has unique antiviral properties as a non-competitive, non-chain terminating HBV polymerase inhibitor that distorts the active site of HBV polymerase resulting in potent HBV antiviral activity and extended off-treatment suppression of HBV DNA. ATI-2173 targets the liver, delivering high levels of the unique 5’- triphosphate while limiting systemic exposure to the parent L-nucleoside. ATI-2173 has the potential to become an integral part of a curative combination regimen for chronic hepatitis B.

About Antios Therapeutics Inc.

Antios Therapeutics is a clinical-stage biopharmaceutical company focused on the development of innovative therapies to treat and cure viral diseases. Antios is currently developing ATI-2173, aiming to provide chronic hepatitis B infected patients with a curative combination regimen.

Former biopharmaceutical executive has been at the forefront of developing treatments for infectious diseases of the liver including HBV and HCV

ATLANTA, GA, Feb. 11, 2021 (GLOBE NEWSWIRE) – Antios Therapeutics, Inc. (“Antios”) today announced the appointment of Patrick T. Higgins to the company’s board of directors. Mr. Higgins is a highly accomplished biopharmaceutical executive with more than two decades of experience leading companies in the development of therapies to treat infectious diseases of the liver including HBV and HCV.

“We have made significant progress on our lead asset, ATI-2173, a potential backbone treatment in a functional curative regimen for chronic HBV infection,” said Abel De La Rosa, Ph.D., co-founder of Antios and Chairman of its Board of Directors. “In conjunction with the completion of our Phase 1b clinical study in chronic HBV patients and with data expected to be presented at an upcoming medical conference, the addition of Pat’s significant expertise to our Board is very timely. We look forward to his guidance as we advance ATI-2173 in clinical development.”

Mr. Higgins has more than 35 years of biopharmaceutical executive experience of which the last 25 were with companies focused on infectious diseases including HBV and HCV for liver disease. His most recent position was as chief operating officer for Arbutus Biopharma, which is focused on developing a cure for HBV.In a prior role, he was a co-founder and chief executive officer of OnCore Biopharma, which he took public by merging with Tekmira Pharmaceuticals to form Arbutus. Before co-founding OnCore, he served as executive vice president, Commercial, for Pharmasset, which developed sofosbuvir, an FDA-approvedtherapy for HCV. Mr. Higgins was responsible for developing and executing the commercial strategy for sofosbuvir before the Company was acquired by Gilead Sciences in 2012 for $11 billion. Prior to Pharmasset, he led the infectious disease portfolio, including Pegasys® for hepatitis infections, for Hoffman-LaRoche and spent 13 years at Schering Plough in various roles. Mr. Higgins is currently a director on the Board of Saronic Biotechnology. He earned is B.A. at Villanova University and his M.B.A. at Seton Hall University.

“I have spent much of my career in the pharmaceutical industry working for companies seeking treatments and cures for chronic hepatitis infections,” said Mr. Higgins. “Antios is focused on developing a functional cure for HBV, a public health objective that has yet to be achieved. I am looking forward to working with the Antios team to make this dream a reality.”

About ATI-2173

ATI-2173 is a novel, orally-administered, liver-targeted Active Site Polymerase Inhibitor Nucleotide (ASPIN) molecule designed to deliver the 5’-monophosphate of clevudine to the liver. This L-nucleoside’s active 5’-triphosphate has unique antiviral properties as a non-competitive, non-chain terminating HBV polymerase inhibitor that distorts the active site of HBV polymerase resulting in potent HBV antiviral activity and extended off-treatment suppression of HBV DNA. ATI-2173 targets the liver, delivering high levels of the unique 5’- triphosphate while limiting systemic exposure to the parent L-nucleoside. ATI-2173 has the potential to become an integral part of a curative combination regimen for chronic hepatitis B.

About Antios Therapeutics Inc.

Antios Therapeutics is a clinical-stage biopharmaceutical company focused on the development of innovative therapies to treat and cure viral diseases. Antios is currently developing ATI-2173, aiming to provide chronic hepatitis B infected patients with a curative combination regimen.

Study results expected to be presented in mid-2021

ATLANTA, GA, Jan. 25, 2021 (GLOBE NEWSWIRE) – Antios Therapeutics, Inc. (“Antios”) today announced that it has completed the Phase 1b clinical trial of ATI-2173, an Active Site Polymerase Inhibitor Nucleotide (ASPIN), in patients with chronic hepatitis B virus (HBV) infection. The Company expects to present the results of this study at an upcoming major medical conference in mid-2021.

“Despite the availability of a vaccine, HBV remains a serious global public health problem with more than 250 million people worldwide living with chronic infection,” said Gregory Mayes, chief executive officer of Antios. “Life-long treatment with nucleoside analogues can control the infection by suppressing viral replication, but it rapidly rebounds in most patients when medication is stopped. ATI-2173’s unique mechanism of action positions it as a promising clinical candidate and potential backbone treatment in a functional curative regimen for chronic HBV infection. We look forward to presenting the data to the scientific community at an upcoming medical conference.”

The placebo-controlled Phase 1b trial evaluated the safety, tolerability, pharmacokinetics, and measurable reductions in HBV viral load of multiple oral doses of ATI-2173 in 24 patients with chronic HBV infection. The patients were randomized 6:2 to three dose cohorts: 10 mg, 25 mg or 50 mg of ATI-2173 or placebo, dosed orally, once-daily for 28 days. All doses were generally well tolerated with no apparent dose relationship for occurrence of adverse events, and no serious adverse events were observed. Based on the potent viral response observed, the 25 and 50 mg doses have been selected for the next clinical study that is expected to start in early 2021. More information on the trial can be found at https://clinicaltrials.gov/ct2/show/NCT04248426?term=ATI-2173&draw=2&rank=1.

About ATI-2173

ATI-2173 is a novel, orally-administered, liver-targeted Active Site Polymerase Inhibitor Nucleotide (ASPIN) molecule designed to deliver the 5’-monophosphate of clevudine to the liver. This L-nucleoside’s active 5’-triphosphate has unique antiviral properties as a non-competitive, non-chain terminating HBV polymerase inhibitor that distorts the active site of HBV polymerase resulting in potent HBV antiviral activity and extended off-treatment suppression of HBV DNA. ATI-2173 targets the liver, delivering high levels of the unique 5’- triphosphate while limiting systemic exposure to the parent L-nucleoside. ATI-2173 has the potential to become an integral part of a curative combination regimen for chronic hepatitis B.

About Antios Therapeutics Inc.

Antios Therapeutics is a clinical-stage biopharmaceutical company focused on the development of innovative therapies to treat and cure viral diseases. Antios is currently developing ATI-2173, aiming to provide chronic hepatitis B infected patients with a curative combination regimen.

Former CEO and Antios co-founder, Abel De La Rosa, Ph.D., appointed Chairman of the Board of Directors
Mayes to lead continued development of ATI-2173 as a potential backbone of a curative regimen for Hepatitis B (“HBV”)

ATLANTA, GA, Dec. 01, 2020 (GLOBE NEWSWIRE) – Antios Therapeutics, Inc. (“Antios”) today announced the appointment of Gregory T. Mayes as Chief Executive Officer and Director. Mr. Mayes succeeds Abel De La Rosa, Ph.D., who co-founded Antios in 2018 and has served as CEO and Director since its inception. Dr. De La Rosa, who is retiring from his full-time role, will remain with Antios as an advisor and will assume the role of Chairman of its Board of Directors.

“On behalf of our Board of Directors, we are thrilled to have Greg join Antios as our new CEO and lead the company to its next stage of development,” said Dr. De La Rosa. “Greg is an accomplished biopharma executive with a sterling track record of success at both building startups and managing established organizations. He has led companies through early- and late-stage clinical development programs as well as commercial launches. Our lead clinical candidate, ATI-2173, is approaching an important inflection point in its development with the upcoming readout from our Phase 1 study in both healthy volunteers and HBV-infected subjects and the commencement of our Phase 2 program in early 2021.”

“Having led Antios from preclinical development to the well capitalized, clinical stage biopharmaceutical company it is today, I feel this is the opportune time for a leadership change. I truly believe that we are well positioned for continued success and I am confident that Antios will flourish under Greg’s leadership. As a co-inventor of ATI-2173, I am deeply committed to its success, and look forward to remaining actively involved, both as Chairman of the Board and in my new role as Senior Scientific and Strategic Advisor.”

Mr. Mayes joins Antios following the acquisition of Engage Therapeutics (“Engage”) by UCB in June 2020. He co-founded Engage and served as CEO from 2017 until its acquisition, which came following positive data from a large, randomized Phase 2 clinical trial of its lead product candidate in development for a new product category called REST (Rapid Epileptic Seizure Termination). Prior to founding Engage, he was Chief Operating Officer and a Board member at Advaxis Immunotherapies, where he developed the Phase 3 registration strategy and clinical development plan for its lead product candidate and established multiple major pharma partnerships. Previously, he was President, General Counsel and Board member at Unigene Laboratories, where he led out-licensing efforts for a novel oral peptide delivery platform. He was also Vice President, General Counsel, and Chief Compliance Officer at ImClone Systems (“ImClone”), where he was actively involved in the clinical development and commercial launch plans for ERBITUX® (cetuximab) and was instrumental in ImClone’s sale to Eli Lilly in 2008. He began his career as Senior Counsel at AstraZeneca Pharmaceuticals LP, where he provided legal services related to the development and commercialization of multiple oncology products. He earned his J.D. degree from Temple University School of Law, where he was Articles Editor on the Temple Law Review and holds a bachelor’s degree from Syracuse University. Mayes currently sits on the Boards of AVEO Oncology and Receptor Life Sciences.

“I am extremely grateful to the Board for this opportunity and excited to build upon the solid foundation that Abel and his team have established over the last several years,” said Mr. Mayes. “In ATI-2173, we have a promising clinical candidate and compelling scientific rationale to position it as the potential backbone of a functional cure regimen for HBV, a significant unmet need. I look forward to leading its continued clinical development and to the many opportunities that lie ahead for Antios.”

About ATI-2173

ATI-2173 is a novel liver-targeted molecule designed to deliver the 5’-monophosphate of clevudine. This L-nucleoside’s active 5’-triphosphate has unique antiviral properties as a non-competitive, non-chain terminating HBV polymerase inhibitor. By selectively delivering the 5’-monophosphate to the liver, while retaining the unique anti-HBV activity of the active 5’- triphosphate, ATI-2173 could become an integral part of a curative combination regimen for chronic hepatitis B.

About Antios Therapeutics Inc.

Antios Therapeutics is a clinical-stage biopharmaceutical company focused on the development of innovative therapies to treat and cure viral diseases. Antios is currently developing ATI-2173, aiming to provide chronic hepatitis B infected patients with a curative combination regimen.