HOOKIPA Pharma announces publication of preclinical data of HBV therapeutic vaccine developed in collaboration with Gilead Sciences

• HB-400, a novel arenaviral therapeutic vaccine, generates robust T cell responses specific to hepatitis B virus with high antibody levels in a preclinical setting
• A Gilead-led Phase 1 clinical trial to evaluate the safety and tolerability of HB-400 in humans is ongoing
• Peer-reviewed data published in The Journal of Infectious Diseases

NEW YORK and VIENNA, Austria, Oct. 18, 2023 (GLOBE NEWSWIRE) — HOOKIPA Pharma Inc. (NASDAQ: HOOK, ‘HOOKIPA’), a company developing a new class of immunotherapeutics based on its proprietary arenavirus platform, today announced that The Journal of Infectious Diseases has published preclinical data on HB-400, an investigational therapeutic vaccine for chronic hepatitis B developed in collaboration with Gilead Sciences, Inc. (HB-400 is also referenced as GS-2829 and GS-6779.) The published data highlight HB-400 as a potential component in achieving a functional cure for chronic hepatitis B.

HB-400 is an alternating, 2-vector non-replicating arenaviral therapeutic vaccine for the treatment of chronic hepatitis B. It uses the Lymphocytic Choriomeningitis Virus and Pichinde Virus as arenaviral backbones, with each expressing three highly conserved hepatitis B virus antigens. HOOKIPA’s alternating 2-vector approach is designed to optimize and focus the immune response against the target antigens. HB-400 is one of two independent development programs in HOOKIPA’s collaboration and license agreement with Gilead Sciences, Inc.

The preclinical data published in The Journal of Infectious Diseases show that:

• Immunization with HB-400 induced robust, hepatitis B-specific T cell and antibody responses in non-human primates; and
• HB-400 vaccination cleared detectable serum hepatitis B antigens in a mouse model for chronic HBV infection, with near elimination of detectable hepatitis B antigen positive hepatocytes in the liver.

A Gilead-led Phase 1 clinical trial (NCT05770895) is currently underway to evaluate the safety and tolerability of repeated doses of HB-400 in healthy participants and individuals with chronic hepatitis B. Gilead is solely responsible for further development and commercialization of HB-400.

“The lack of curative therapies for chronic hepatitis B infection is a significant barrier to addressing the global burden of disease,” said Joern Aldag, Chief Executive Officer at HOOKIPA. “We’re pleased to see our novel arenaviral platform technology featured in this reputable journal, and we look forward to seeing how clinical results of Gilead’s ongoing Phase 1 trial of HB-400 may further support its potential as a component of a functional cure regimen for hepatitis B.”

About Hepatitis B
Hepatitis B virus is the leading cause of liver cancer, as well as a major cause of cirrhosis, liver failure and death globally. It is estimated that nearly 300 million people live with chronic hepatitis B infection, and there are 1.5 million new infections annually.

About HOOKIPA
HOOKIPA Pharma Inc. (NASDAQ: HOOK) is a clinical-stage biopharmaceutical company focused on developing novel immunotherapies, based on its proprietary arenavirus platform, which are designed to mobilize and amplify targeted T cells and thereby fight or prevent serious disease. HOOKIPA’s replicating and non-replicating technologies are engineered to induce robust and durable antigen-specific CD8+ T cell responses and pathogen-neutralizing antibodies. HOOKIPA’s pipeline includes its wholly owned investigational arenaviral immunotherapies targeting Human Papillomavirus 16-positive cancers, prostate cancers, and other undisclosed programs. HOOKIPA is collaborating with Roche on an arenaviral immunotherapeutic for KRAS-mutated cancers. In addition, HOOKIPA aims to develop functional cures of HBV and HIV in collaboration with Gilead.

Find out more about HOOKIPA online at www.hookipapharma.com.