Vir Biotechnology Announces First Patient Dosed in the Phase 2 SOLSTICE Trial Evaluating VIR-2218 and VIR-3434 for the Treatment of Chronic Hepatitis D Virus Infection

– Impacting more than 12 million people globally, HDV is the most aggressive form of viral hepatitis –

– Novel combination strategy designed to
reduce HDV viremia and block viral entry –

SAN FRANCISCO, Sept. 22, 2022 (GLOBE NEWSWIRE) — Vir Biotechnology, Inc. (Nasdaq: VIR) today announced that the first patient has been dosed in the Phase 2 SOLSTICE clinical trial evaluating VIR-2218 and VIR-3434 as monotherapy and in combination for the treatment of people living with chronic hepatitis D virus (HDV), which occurs as a simultaneous co-infection or super-infection alongside hepatitis B virus (HBV). HDV infection, the most aggressive form of viral hepatitis, increases the risk of poor outcomes, including liver cancer and death, compared with HBV alone.

VIR-2218 is an investigational small interfering ribonucleic acid (siRNA) that diminishes the level of all HBV proteins in vitro, including hepatitis B surface antigen, a protein necessary to create infectious HDV virions. VIR-3434 is an investigational hepatitis B surface antigen targeting monoclonal antibody designed to remove both HBV and HDV virions from the blood and block the entry of these viruses into liver cells. VIR-2218 and VIR-3434 are currently being evaluated for the treatment of HBV in the Phase 2 MARCH (Monoclonal Antibody siRNA Combination against Hepatitis B) trial. Previously reported results from Part A of the MARCH trial demonstrated that the combination of VIR-3434 and VIR-2218 resulted in an approximate 3 log decline in hepatitis B surface antigen (HBsAg).

“Globally, more than 12 million people are living with HDV, and with no approved therapies available in the United States, there is an urgent need for the development of novel treatment strategies that will improve outcomes for patients,” said Carey Hwang, M.D., Ph.D., Vir’s senior vice president, clinical research, head of chronic infection. “Recent research suggests that reducing HDV viremia, by preventing virion formation as well as facilitating virion removal, in conjunction with blocking HDV virion entry into liver cells could be effective in suppressing chronic HDV infection. The initiation of SOLSTICE, our first clinical trial in HDV, is an important milestone as we advance our broad therapeutic portfolio for viral hepatitis, which also includes the pursuit of a functional cure for chronic HBV infection.”

Design of the Phase 2 SOLSTICE Trial
The multi-center, open-label Phase 2 SOLSTICE trial is designed to evaluate the safety, tolerability, and efficacy of VIR-2218 and VIR-3434 in adult patients (age 18 to 69) with chronic HDV infection receiving nucleot(s)ide reverse transcriptase inhibitor therapy. Depending on the cohort, trial participants will receive multiple doses of VIR-2218 and VIR-3434 as either monotherapy or in combination administered via subcutaneous injection for up to 88 weeks. The primary endpoints of the trial are the proportion of study participants achieving either a ≥ 2log10 decrease in HDV RNA compared to baseline, or HDV RNA less than the limit of quantification and normalization of alanine transaminase (ALT) at Week 24, as well as the proportion of participants with treatment-emergent adverse events and serious adverse events. Vir expects initial data from the SOLSTICE trial in 2023.

About Chronic Hepatitis D
Chronic hepatitis D virus (HDV) infection occurs as a simultaneous co-infection or super-infection with hepatitis B virus (HBV). An estimated 12 million patients globally are infected with HDV, representing approximately 5% of those infected with HBV. HDV-HBV co-infection is considered the most severe form of chronic viral hepatitis due to more rapid progression toward hepatocellular carcinoma and liver-related death.

About Chronic Hepatitis B
Chronic hepatitis B virus (HBV) infection remains an urgent global public health challenge associated with significant morbidity and mortality. Approximately 300 million people around the world are living with HBV and approximately 900,000 of them die from associated complications each year. These patients are significantly underserved by existing therapies with low functional cure rates, lifelong daily therapy and poor tolerability. Vir is working to achieve a functional cure for the millions of people with HBV around the world through its broad and differentiated portfolio.

About VIR-2218
VIR-2218 is an investigational subcutaneously administered HBV-targeting siRNA that has the potential to stimulate an effective immune response and have direct antiviral activity against HBV and HDV. It is the first siRNA in the clinic to include Enhanced Stabilization Chemistry Plus (ESC+) technology to enhance stability and minimize off-target activity, which potentially can result in an increased therapeutic index. VIR-2218 is the first asset in the Company’s collaboration with Alnylam Pharmaceuticals, Inc. to enter clinical trials.

About VIR-3434
VIR-3434 is an investigational subcutaneously administered antibody designed to block entry of HBV and HDV viruses into hepatocytes and to reduce the level of virions and subviral particles in the blood. VIR-3434, which incorporates Xencor’s Xtend™ and other Fc technologies, has been engineered to potentially function as a T cell vaccine against HBV and HDV in infected patients, as well as to have an extended half-life.

About Vir Biotechnology
Vir Biotechnology is a commercial-stage immunology company focused on combining immunologic insights with cutting-edge technologies to treat and prevent serious infectious diseases. Vir has assembled four technology platforms that are designed to stimulate and enhance the immune system by exploiting critical observations of natural immune processes. Its current development pipeline consists of product candidates targeting COVID-19, hepatitis B and hepatitis D viruses, influenza A and human immunodeficiency virus. Vir routinely posts information that may be important to investors on its website.

Forward-Looking Statements
This press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. Words such as “may,” “will,” “plan,” “potential,” “aim,” “expect,” “anticipate,” “promising” and similar expressions (as well as other words or expressions referencing future events, conditions, or circumstances) are intended to identify forward-looking statements. These forward-looking statements are based on Vir’s expectations and assumptions as of the date of this press release. Forward-looking statements contained in this press release include, but are not limited to, statements regarding the ability of VIR-2218 and VIR-3434 in combination to treat chronic HDV and HBV infection; the potential benefits of VIR-2218 and VIR-3434; Vir’s plans and expectations for its HDV and HBV portfolios; the initial results of the MARCH trial; the timing for and design of the Phase 2 SOLSTICE trial; the treatment of HDV and HBV; and risks and uncertainties associated with drug development and commercialization. Many factors may cause differences between current expectations and actual results, including risks that Vir may not fully enroll the Phase 2 SOLSTICE trial or it will take longer than expected; unexpected safety or efficacy data or results observed during the Phase 2 SOLSTICE trial or in data readouts; the occurrence of adverse safety events; risks of unexpected costs, delays or other unexpected hurdles; difficulties in collaborating with other companies; challenges in accessing manufacturing capacity; successful development and/or commercialization of alternative product candidates by Vir’s competitors; changes in expected or existing competition; delays in or disruptions to Vir’s business or clinical trials due to the COVID-19 pandemic, geopolitical changes or other external factors; and unexpected litigation or other disputes. Drug development and commercialization involve a high degree of risk, and only a small number of research and development programs result in commercialization of a product. Results in early-stage clinical trials may not be indicative of full results or results from later stage or larger scale clinical trials and do not ensure regulatory approval. You should not place undue reliance on these statements, or the scientific data presented. Other factors that may cause actual results to differ from those expressed or implied in the forward-looking statements in this press release are discussed in Vir’s filings with the U.S. Securities and Exchange Commission, including the section titled “Risk Factors” contained therein. Except as required by law, Vir assumes no obligation to update any forward-looking statements contained herein to reflect any change in expectations, even as new information becomes available.

CONTACT: Contacts:

Investors
Heather Rowe Armstrong
VP, Investor Relations
harmstrong@vir.bio
+1-415-915-4228

Media
Carly Scaduto
Senior Director, Media Relations
cscaduto@vir.bio
+1-314-368-5189