Vaxdyn and the EIC Accelerator: A Superbug Vaccine Not Yet Tested

Vaxdyn, founded in 2011 as a spin-off of the Institute of Biomedicine of Seville, is developing vaccines against antibiotic-resistant bacteria using inactivated, endotoxin-free whole cells of Acinetobacter baumannii that display proteins from other pathogens on their surface. Its EIC Accelerator project, K-VAX, "Clinical validation of an antibiotic-resistant bacteria global vaccine platform through the first vaccine against Klebsiella pneumoniae", receives an EU contribution of €2,494,749 and runs from January 2025 to December 2026, according to CORDIS. Its goal is to take the K-VAX vaccine candidate from preclinical development into a Phase 1/2 trial in humans.

After its first 12 months, the project report describes preparation, not a trial: generating data for the clinical plan, preparing documentation for trial authorisation, identifying sites and strengthening the quality and safety data required "prior to human testing", according to CORDIS. Vaxdyn's pipeline page still lists K-VAX at "Pre-clinical development" with "First proof of principle in humans expected in 2025", according to Vaxdyn. Searches of ClinicalTrials.gov and the EU's CTIS register found no Vaxdyn trial. In September 2026 Vaxdyn announced an €11 million Series A with the EIC Fund to pay for the first-in-human Phase 1 trial of K-VAX, according to Vaxdyn.

Where Vaxdyn Stands Now

Vaxdyn is a small company. The Spanish register lists nine employees and puts its 2024 sales in the €500,000 to €1 million bracket, according to Empresia. Its board was reshaped in October 2024 and now includes Ricardo Perdigão Henriques of Biovance Capital and, per the company, Cristina Reina of Arcano. The CEO says the Series A marks the company's move to "a clinical-stage company".

The Technology: A Bacterium Stripped of Its Toxin

Vaxdyn's platform uses Acinetobacter baumannii cells that lack lipopolysaccharide, the endotoxin that makes whole-cell bacterial vaccines too toxic for use. The company says this focuses immunity on conserved outer membrane proteins rather than the variable sugar capsules that existing approaches target, and that K-VAX is designed to raise immunity against all circulating strains of K. pneumoniae and A. baumannii. Those claims come from animal studies; no human data has been published. Other candidates target Pseudomonas aeruginosa, E. coli and a pig pneumonia pathogen.

What the EIC Award Promised, and What the Record Shows

The EIC project promised clinical validation in humans within two years. With three months left, no trial is registered in the US or EU databases, and the company's own 2025 target for first human data has passed. The project formally runs until December 2026, so a final judgement is premature.

1. Clinical trial documentationIn progressProject report.
2. Phase 1/2 trial startedNot registeredNo CTIS or US entry.
3. Human proof of principle, 2025Not shownWebsite target; no trial found.
4. Funding for the trialRaised€11M Series A.

The Money

Biovance Capital led the Series A with €4 million and Impacto Andalucía, a fund managed by Arcano with European Regional Development Fund and Andalusian government money, invested €3.6 million. The EIC Fund and existing shareholders provided the rest; the EIC Fund's share was not disclosed. CARB-X, the US-funded antibacterial accelerator, committed up to $892,000 in 2020 plus $6.36 million on milestones, according to Vaxdyn. Before 2026, private investment was small: Bionova Capital and Arquimea bought €300,000 of shares each in 2021, according to Vaxdyn.

What Cannot Be Checked

Why Europe Should Care

Klebsiella pneumoniae is one of the World Health Organization's most critical drug-resistant pathogens and no vaccine against it is approved. A European vaccine would matter. But the field is moving: Cho Pharma of Taiwan started a Phase 1 trial of a Klebsiella vaccine in June 2025, according to ClinicalTrials.gov, while Vaxdyn is still preparing its first.

The Verdict

Vaxdyn and the EIC have not been asked for comment for this article. It is based entirely on public records and published statements, linked throughout.