AdJane reports first human proof-of-concept for intranasal OMV vaccine
AdJane, a clinical-stage vaccine company based in Delft, has published first-in-human Phase I data showing that its native outer membrane vesicle (nOMV) platform can induce immune responses at the nasal mucosa as well as systemically. The results, which appeared in the peer-reviewed journal Vaccines, are positioned by the company as clinical proof-of-concept for an intranasal vaccine modality that could complement or eventually rival conventional injectable approaches for respiratory pathogens.
The randomised, double-blind, placebo- and OMV-controlled trial enrolled 40 healthy, SARS-CoV-2 seropositive adults aged 18 to 55. Participants received an intranasal formulation combining the nOMV adjuvant with a SARS-CoV-2 Spike protein antigen. The study demonstrated dose-dependent systemic immune responses across multiple measures, including virus-neutralising antibodies, alongside measurable immune activity at the nasal mucosa. The company reported the formulation was safe and well tolerated across all dose groups. Full data are available via the journal and the trial is registered at ClinicalTrials.gov under identifier NCT05604690.
"Current injectable vaccines are highly effective at preventing severe disease but have shown limited ability to interrupt infection and transmission at the mucosal level," said Anita Gashi, Managing Director of AdJane. "Our Phase I data demonstrate that intranasal OMV-based vaccination can safely induce both systemic and mucosal immunity in humans."
Platform and pipeline context
AdJane's nOMV technology derives from more than three decades of research at Dutch governmental institutions and uses outer membrane vesicles from Neisseria meningitidis as the immunostimulatory scaffold. Four proprietary genetic modifications are incorporated to address safety and manufacturing considerations. The company describes the platform as modular, allowing antigens from different pathogens to be integrated without redesigning the core adjuvant system.
Beyond the SARS-CoV-2 demonstrator, the platform is being applied in a pandemic preparedness collaboration with CEPI targeting broad-spectrum respiratory viral protection, and in a CARB-X-supported programme against multidrug-resistant Neisseria gonorrhoeae, a bacterial pathogen responsible for an estimated 80 million new infections a year globally. The company also reports platform stability under standard refrigeration for more than two and a half years, a characteristic that, if maintained in later-stage studies, would reduce cold-chain constraints for low- and middle-income market deployment.
Competitive landscape and regulatory read-across
The mucosal vaccine space has attracted sustained attention since the COVID-19 pandemic exposed the limited transmission-blocking effect of intramuscular immunisation. Several programmes, including intranasal adenoviral-vector and live-attenuated approaches, have advanced into clinical evaluation in China, India, and Europe, with mixed readouts on mucosal IgA induction. The nOMV approach occupies a distinct mechanistic niche: bacterial vesicles are potent activators of innate pattern-recognition receptors, which may support stronger mucosal priming than some viral-vector alternatives, though a direct comparative dataset does not yet exist.
Regulatory agencies including the FDA and EMA have not yet established a harmonised framework for licensure of transmission-blocking mucosal vaccines, meaning that trial design and endpoints for later phases will require careful alignment with regulators. AdJane will need to define a specific indication and confirm mucosal IgA durability over time before a Phase II programme can be substantively de-risked. For now, the Phase I publication provides the clinical anchor the company needs to attract partnership conversations and further non-dilutive funding, particularly given its existing relationships with CEPI and CARB-X.
The near-term milestones to watch are the announcement of a lead indication beyond the SARS-CoV-2 platform demonstrator and any Phase II design details that emerge from the CEPI pandemic-preparedness collaboration.