Oxford/CEPI Lassa vaccine enters clinical trial in Nigeria

NIGERIA—Oxford researchers have administered the first dose of an experimental Lassa fever vaccine to a volunteer, marking a major breakthrough in the fight against a deadly virus that currently has no licensed vaccine or treatment.

The Oxford Vaccine Group developed the ChAdOx1 Lassa vaccine with funding from the Coalition for Epidemic Preparedness Innovations (CEPI), bringing hope to millions of people across West Africa who face this severe disease.

Lassa fever first appeared in Nigeria during the late 1960s and continues to threaten populations throughout West Africa, where the disease remains endemic.

The virus spreads primarily through contact with infected rodents and causes serious complications, including permanent deafness, severe bleeding, and often death.

Recognizing these substantial public health risks, the World Health Organization has classified Lassa fever and related viruses as priority pathogens requiring urgent research and development.

Researchers project that up to 700 million people could live in regions vulnerable to Lassa fever by 2070.

Despite this alarming forecast, no licensed vaccines or treatments currently exist for the disease, making this trial particularly crucial for vulnerable populations.

Scientists at the University of Oxford’s Pandemic Sciences Institute developed the vaccine using the same viral vector technology that powered the Oxford/AstraZeneca COVID-19 vaccine, which researchers estimate saved 6 million lives during its first year of distribution.

The clinical trial will now assess the vaccine’s safety and immune response in 31 healthy volunteers between the ages of 18 and 55.

Professor Maheshi Ramasamy, who serves as Chief Investigator of the VITAL01 Lassa fever vaccine study at the Oxford Vaccine Group, emphasized that vaccines represent one of the most powerful tools available in global health.

 She noted that the trial builds directly on Oxford’s leading experience in developing vaccines for emerging infections and pandemics, including COVID-19.

Dr. Katrin Ramsaeur, who leads CEPI’s Lassa Disease Programme, described the trial launch as a transformative milestone resulting from years of rigorous science, sustained collaboration, and dedication to global health.

Meanwhile, Dr. Virgil Lokossou, Director of Healthcare Services at the West African Health Organization (WAHO), highlighted that Lassa fever has impacted families, livelihoods, hospitals, and economies throughout the region for more than half a century.

He expressed optimism that collaborative efforts through partnerships like the Lassa fever Coalition are positioning West Africa to confront this epidemic threat more effectively than ever before.