Cambridge completes first human trial of pan-sarbecovirus vaccine

The University of Cambridge has made significant strides in vaccine development by completing the first human trial of pEVAC-PS, a pan-sarbecovirus vaccine candidate. This vaccine aims to protect against the entire family of sarbecoviruses, which not only includes COVID-19 but also potential future coronaviruses. The trial results indicate that the vaccine was safe and well tolerated among participants, paving the way for further studies to explore its efficacy. This innovative vaccine, developed by a team led by Jonathan Heeney, DVM, Ph.D., utilizes advanced AI technology to generate an effective immune response.

The research team used extensive genetic sequence data from sarbecoviruses collected globally. They employed a platform called Digitally Immune Optimized Synthetic Vaccine to design a super-antigen that incorporates common features of these viruses. This approach addresses a critical limitation of traditional vaccines, which often target specific strains that may mutate before widespread distribution. The Phase 1 trial involved 39 healthy adults aged between 18 and 50, all of whom had received previous COVID-19 vaccinations. Participants were divided into four groups, each receiving two doses of varying amounts.

The vaccine was administered using a microfluidic jet method, eliminating the need for needles, which can be advantageous in settings where cold-chain storage is challenging. The study found that the vaccine was well tolerated across all doses, with no serious adverse effects reported. Although the immune responses observed were modest, the trial did show that participants developed antibodies targeting conserved regions of the coronavirus spike protein. This response aligns with the vaccine's design, aimed at providing broader protection across various strains.

Researchers noted that the timing of the trial, which coincided with waves of COVID-19 variants, complicated the interpretation of results, as many participants had prior immunity from vaccination. Looking ahead, the team at Cambridge plans to initiate a larger Phase 2 trial to further investigate the vaccine's efficacy. The successful completion of this trial marks a pivotal moment in vaccine research, particularly in addressing the challenges posed by rapidly mutating viruses. The potential of pEVAC-PS to offer durable protection against a wide range of coronaviruses could significantly enhance public health measures in combating future outbreaks.