Haemophilus Influenzae Meningitis Clinical Trial
Official title:
A Phase I Randomized, Observer-blind, Placebo-controlled Trial of a Haemophilus Influenzae Serotype A (Hia) Glycoconjugate Vaccine With Alum Adjuvant in Young Adults 18 to 40 Years of Age
Haemophilus influenzae serotype a (Hia) has emerged as a leading cause of serious illness in Indigenous children in Canada and Alaska in recent decades. In hospital-based surveillance studies, Hia was the most common cause of invasive disease, resulting in morbidity or mortality after Haemophilus influenzae serotype b (Hib). Given the success of the Hib vaccine program and the pathophysiologic similarities between Hib and Hia, immunization is the obvious way to protect Indigenous children living in small and scattered communities. The Public Health Agency of Canada has been working with the National Research Council and other members of the Consortium, including the Canadian Immunization Research Network, McGill Interdisciplinary Initiative in Infection and Immunity, GlycoNet, the Hewitt Foundation, and Inventprise/InventVacc, to develop a Hia vaccine for prevention of this deadly infection. The engagement process initiated by NRC with Consortium members and representatives from Indigenous groups, particularly, has led to the current project plan. In this first-in-human study, we propose investigating the safety and immunogenicity of a novel glycoconjugate candidate vaccine that uses protein carrier CRM197 in healthy adults in the general population. The study will be conducted at the McGill University Health Center Vaccine Study Centre in Montreal and the Canadian Center for Vaccinology in Halifax. The findings of this Phase I study will be necessary to effectively move this potential vaccine solution further along the development continuum.
Haemophilus influenzae serotype a (Hia) can cause invasive diseases, including sepsis and meningitis, similar to serotype b (Hib). In the post-Hib vaccine era, Hia emerged as a prominent cause of invasive infection, largely in Indigenous northern populations in North America. The development of a candidate vaccine to prevent invasive disease due to Hia was initiated by the National Research Council of Canada (NRC) and the Public Health Agency of Canada (PHAC), and the candidate was later licensed to Inventprise/InventVacc Biologicals for further development. Given the success of the Hib vaccine program and the pathophysiologic similarities between Hib and Hia, immunization and the dosing of the Hia vaccine will greatly resemble Hib vaccines. This candidate Hia vaccine will be tested in a randomized, controlled, observer-blind Phase I study in healthy young individuals 18 to 40 years of age from the general population to determine its safety and immunogenicity. This study will be conducted at two sites: the McGill University Health Centre (MUHC) Vaccine Study Centre in Montreal and the Canadian Center for Vaccinology (CCfV) in Halifax; both are study sites of the Canadian Immunization Research Network (Clinical Trials Network). The primary objective of this study is to assess the safety of this novel Hia vaccine. Following vaccine receipt, participants will collect solicited adverse events (AE) in the next 7 days and unsolicited AE for 28 days. Blood for immunogenicity and SBA will be collected on Day 28 after each vaccine dose and on Day 208. Immunogenicity data will be collected as a secondary outcome. The protective capacities of antibodies induced with the Hia vaccine will be directly assessed in vitro with a Hia-specific SBA using a qualified assay developed at the NRC. The SBA titers will be defined as the reciprocal serum dilution required to kill > 50% of the initial bacterial inoculum. Early Hib studies demonstrated the clinical usefulness of a salivary assay for the assessment of mucosal antibody responses during invasive disease and vaccination status once the Hib vaccine was developed. A similar approach can be applied to Hia studies since saliva sampling and testing may provide a non-invasive correlate/surrogate of vaccine-induced immunity that could be very useful in the later-stage development of the vaccine in children and infants. Thus, our Consortium members for Hia have developed a laboratory method for measuring the specific IgA response against Hia-CPS in saliva, which will be used in the exploratory objective. If shown to be safe and immunogenic, and after further consultation and engagement with Indigenous communities, enrolment of Indigenous people in the later phases of the clinical development will be prioritized. ;