In short
Escherichia coli (inactivated) is a vaccine containing killed bacteria from specified strains of Escherichia coli and other enterobacteria. It is being studied as StroVac for the prevention of urinary tract infections. One authorised Phase 3 trial with 20 participants is evaluating laboratory methods to measure immune responses after vaccination.
Key points
- Phase 3 proof-of-concept trial in urinary tract infection
- 20 participants enrolled in a single authorised trial
- Measures IgG antibodies in blood and IgA antibodies in urine after vaccination
- Tests laboratory methods including opsonophagocytosis assay and agglutination test
- Vaccine contains inactivated bacteria from 10 specified enterobacterial strains
- Trial registered in the EU Clinical Trials Information System as 2026-527508-25-00
What is Escherichia coli (inactivated)?
Escherichia coli (inactivated) is a vaccine preparation containing killed (inactivated) bacteria from specified strains of Escherichia coli and other enterobacteria. The product studied in the registered trial is StroVac, an injection suspension whose active substance consists of inactivated germs of specified enterobacteria at a 501 mg dose. Escherichia coli is a group of bacteria that normally lives in the gut of healthy people and animals; most strains are harmless, but some can cause infections in the urinary tract and other parts of the body. Urinary tract infections caused by E. coli are among the most common types of infections in women. The World Health Organization notes that most E. coli strains are harmless, while some, such as Shiga toxin-producing E. coli (STEC), can cause severe foodborne disease.
How does Escherichia coli (inactivated) work?
The vaccine is designed to stimulate an immune response against the bacterial strains it contains. The registered trial measures whether vaccination increases patient-specific IgG antibodies in blood plasma and IgA antibodies in urine against each of the target bacterial strains from baseline to post-vaccination. The trial also investigates whether laboratory methods can detect functional antibodies: the opsonophagocytosis assay (OPA), which measures whether immune cells can engulf bacteria; the agglutination test, which detects whether antibodies can clump bacteria together; and the neutralisation test, which assesses whether antibodies can block bacterial activity. These assays help determine whether the vaccine produces antibodies that could potentially help the body defend against urinary tract infections.
Which conditions is Escherichia coli (inactivated) used or studied for?
- Urinary tract infection — the registered trial investigates immune responses after StroVac vaccination in the context of urinary tract infection.
How is Escherichia coli (inactivated) given?
StroVac is given as an injection suspension. The trial intervention describes a 501 mg dose of inactivated germs of specified enterobacteria administered by application.
What do the clinical trials show?
One trial is registered in the EU Clinical Trials Information System (EU CT number 2026-527508-25-00). It is a Phase 3, interventional, proof-of-concept study with 20 participants, currently authorised. The trial does not primarily measure clinical outcomes; instead, it evaluates whether laboratory tests are suitable for detecting antibodies induced by StroVac vaccination. The primary outcomes are the increase of patient-specific IgG levels in plasma and IgA levels in urine against each of the 10 bacterial strains contained in StroVac, measured from baseline before vaccination to Visit 4 after vaccination.
What side effects are known?
The provided sources do not report side effects specific to Escherichia coli (inactivated) or StroVac. General information about E. coli infections describes symptoms such as watery diarrhoea, vomiting, fever, and abdominal cramps for some disease-causing strains, but these relate to infection rather than to the vaccine itself.