iiCON supports new phase II trial of novel pneumococcal vaccine, PnuBioVax

The Infection Innovation Consortium: iiCON is managing a new £3.2 million Medical Research Council funded trial to enable progress into development of a new vaccine against pneumococcal disease, which has high rates of antibiotic resistance, and is a major cause of disease worldwide.

Pneumococcal disease remains a global concern and presents a substantial global economic burden. It is the biggest preventable killer of children globally, with most deaths occurring in low and middle income countries (LMICs). This has remained the case despite successful vaccines effective against the serotypes most commonly causing invasive pneumococcal disease in developed countries.

Serotype 3 pneumococcus (SPN3) presents a particular problem as there have been limited changes in incidence of this serotype despite a decade of immunisation programmes with  PCV13(1) and so SPN3 has become the dominant strain in many parts.  SPN3 has become the most common cause of severe pneumonia in children in Europe (Europneumo 2023) and an increasing cause for concern owing to the high prevalence of antimicrobial resistance in SPN3 strains(2).  SPN3 is the most common pneumococcal strain carried in the community in Malawi since the introduction of PCV13;  prevention of carriage would prevent the resulting disease and so this is an urgent local priority.

The proposed solution is to use a protein-based pneumococcal vaccine to prevent transmission of SPN3. This product would be given to people at risk of disease and those with a high risk of transmitting infection to others. The highest transmitting populations in high-risk areas are children and adults with immunocompromise particularly HIV. These populations are also exposed to high levels of antibiotic and so prevention of carriage in these people will reduce the emergence of antimicrobial resistance in pneumococcal isolates.

iiCON is working with small vaccine company ImmBio who developed the vaccine (PnuBioVax) and have already successfully conducted phase I safety and immunogenicity studies. This next stage phase II study will recruit young heathy adults to a controlled human infection model (CHIM) trial in Malawi. The sample group will be vaccinated and then inoculated in their nose to understand if they establish carriage of the bacteria or not. This will be compared to the existing PCV13 vaccine and a placebo. CHIM trials for pneumococcal disease have been well established at the Liverpool School of Tropical Medicine for many years and this trial will build on the current £4.5m MARVELS programme at the Malawi Liverpool Wellcome Programme in Malawi.  MARVELS (Malawi Accelerated Research in Vaccines by Experimental and Laboratory Systems) is a programme to develop CHIM studies in pneumococcus, salmonella and TB of which the leading project is the now well-established pneumococcal CHIM. Following the trial, it is envisaged that the low-cost vaccine may offer potential to be both manufactured and distributed in Africa.

Professor Stephen Gordon, Director of Experimental Medicine at iiCON, said: “iiCON is delighted to receive this funding from the MRC in order to tackle this urgent health priority/public health issue in Malawi. Not only will it save lives, it will help to upskill and boost the local economy as we very much hope that the vaccine will eventually be manufactured and distributed locally. This way, we can ensure the communities that really need this vaccine will be receiving it.  In the development of the vaccine we hope to cover multiple serotypes at low cost and effectively block community transmission.”

Graham Clarke, ImmBio Chairman, said “ImmBio is delighted to be working with iiCON on this project, combining ImmBio’s innovative approach to vaccines with iiCON’s unique ability to progress it with novel clinical studies.  Multi-protein based vaccines have the potential to address pathogen diversity but like all new vaccines, needs a clinical pathway acceptable to regulatory authorities, to successfully address major unmet healthcare needs.”