Vaccitech Ltd, a clinical stage biopharmaceutical company developing immunotherapies to treat and prevent infectious diseases and cancer, announces today that it has dosed the first person in a Phase 1 clinical study to investigate the safety and immunogenicity of the VTP-300 prime in both healthy participants and patients with chronic hepatitis B (HBV) who are virally suppressed with oral antiviral medication. The VTP-300 prime comprises Vaccitech’s Chimpanzee Adenovirus Oxford 1 (ChAdOx1), a non-replicating viral vector delivering three full-length HBV antigens to stimulate a vigorous antibody and mixed CD4+/CD8+ T cell immune response. The study, HBV001, will evaluate the ability of VTP-300 prime to generate anti-HBV CD4+ and CD8+ T cells; immune cells known to be involved in the clearance of HBV from the liver.

HBV001 (ClinicalTrials.gov: NCT04297917), is an open-label, non-randomised, dose escalation study, comparing the safety, tolerability and immunogenicity of two different doses of the VTP-300 prime, ChAdOx1-HBV, across three sites in the UK. It is planned to enrol 10 healthy participants and 12 patients with chronic HBV infection.

Once the VTP-300 prime dose is confirmed, Vaccitech plans to initiate a Phase 1b/2a study, HBV002, in Q3 2020 using the complete VTP-300 heterologous prime-boost regimen. The regimen consists of ChAdOx1-HBV (the prime) and a second non-replicating viral vector, a Modified Vaccinia Ankara (MVA), delivering the same HBV antigens (the boost).

HBV002 will be an international, randomized, open-label study, to be run in Taiwan, China, South Korea and the UK. It is designed to enrol 64 chronically infected HBV patients and assess efficacy through reduction in serum HBV surface antigen. VTP-300 will be administered in combination with standard of care antivirals that limit viral replication and low doses of an anti-PD-1 agent to counteract the T cell exhaustion typically present in chronic HBV patients. Initial data from HBV002 is anticipated in Q3 2021.

Bill Enright, Vaccitech CEO, said, "We are excited to begin testing VTP-300 as a potential functional cure for Hepatitis B infection. Currently no such cure exists for this disease and patients need to take daily medications to help control the virus. We believe that our immunotherapy, in combination with anti-viral medications and checkpoint inhibitors, has a real opportunity to make an impact on patients’ lives."

About Vaccitech Ltd.
Vaccitech is a clinical stage T cell immunotherapy company developing products to treat and prevent cancer and infectious diseases. The company’s proprietary technology platform, comprising Chimpanzee Adenovirus (prime) and MVA (boost) is exceptional at inducing, boosting and maintaining CD8+ and CD4+ T cells, as well as antibodies. The Vaccitech prime-boost platform is licensed from one of the most prestigious vaccine research institutes in the world, the Jenner Institute at the University of Oxford. Vaccitech currently has a Phase 2a clinical programme for prostate cancer and is poised to enter the clinic with HPV and NSCLC therapeutics. The company is also co-developing products for MERS coronavirus and Herpes Zoster with international collaborators and has outlicensed its rights to the ChAdOx COVID-19 vaccine to University of Oxford-AstraZeneca. Vaccitech is backed by leading institutions including GV, Sequoia Capital China, Korea Investment Partners and Oxford Sciences Innovation.