TherVacB, a groundbreaking therapeutic vaccine for chronic hepatitis B, has entered its first clinical trial in humans, representing a potential breakthrough in treating a disease that affects nearly 300 million people worldwide. The Phase 1a trial began on January 25, 2024, at the LMU University Hospital Munich, marking the culmination of 12 years of dedicated research led by Helmholtz Munich.
Novel Approach to Combat Persistent Viral Infection
The open-label, escalating dose study will evaluate the safety and immunogenicity of TherVacB in 24 healthy participants aged 18 to 65 years. Conducted under the sponsorship of the University Medical Center Hamburg-Eppendorf with coordinating investigator Prof. Dr. Marylyn Addo, the trial is being carried out by the Division of Infectious Diseases and Tropical Medicine at LMU University Hospital Munich under Principal Investigator Dr. Mirjam Schunk.
"TherVacB is based on a deep understanding of the challenges of the immune system in chronic hepatitis B infection and is the result of years of dedicated research here in Munich," said Ulrike Protzer, the leading scientist behind the vaccine. "Our approach is designed to induce exactly the type of immunity required and cover a broad spectrum of over 95% of hepatitis B strains worldwide."
Addressing a Global Health Crisis
Chronic hepatitis B, caused by the hepatitis B virus (HBV), represents one of the world's most pressing infectious disease challenges. The World Health Organization estimates that approximately 296 million people worldwide are living with chronic HBV infections, including over 6 million children under the age of 5. The disease claims 820,000 lives annually from complications including liver cirrhosis and liver cancer.
Current treatment options involve antiviral medications that reduce virus load and liver inflammation but do not provide a curative solution. Nucleotide analogs, which form the current standard of care, must be taken daily and are not universally available worldwide, creating an urgent need for curative treatment approaches.
Innovative Therapeutic Vaccine Design
Unlike prophylactic vaccines that prevent illness, TherVacB is designed as a therapeutic vaccine that aims to cure existing chronic infection by boosting the body's immune system to fight the disease. The vaccine addresses a fundamental challenge identified by researchers: the hepatitis B virus prevents certain immune cells from becoming effective against the infection.
Over the past two decades, numerous attempts to develop effective therapeutic hepatitis B vaccines have been unsuccessful. Building upon new discoveries about immune system dysfunction in chronic HBV infection, scientists at Helmholtz Munich, in collaboration with the German Center for Infection Research and the Proof-of-Concept Initiative of the Helmholtz Association and the Fraunhofer-Gesellschaft, developed this novel therapeutic approach to activate suppressed immune cells through vaccination.
Clinical Development Timeline
Results from the Phase 1a study (NCT05727267) are expected to be made public by the end of 2024. Simultaneously, preparations are underway for the first-in-patient Phase 1b/2a trial, which will assess safety and efficacy in patients with chronic hepatitis B. This multi-country study is planned to take place in Germany, Italy, Spain, England, and Tanzania and is funded by the European Union as part of a Horizon 2020 research project.
The transition from extensive preclinical testing to human trials represents a pivotal milestone, achieved after the vaccine was produced adhering to Good Manufacturing Practice guidelines. The global scope of the planned patient trials reflects the worldwide burden of chronic hepatitis B and the potential impact of a successful therapeutic intervention.
