In short
Morganella morganii (inactivated) is an investigational bacterial vaccine component used in StroVac, a product studied for the prevention of recurrent urinary tract infections. One authorised Phase 3 clinical trial is currently evaluating how vaccination with StroVac affects antibody responses against 10 bacterial strains, including Morganella morganii, in 20 participants.
Key points
- Morganella morganii (inactivated) is a component of StroVac, a vaccine studied for urinary tract infections.
- One Phase 3 clinical trial is authorised and plans to enrol 20 participants.
- The trial measures IgG antibodies in blood plasma and IgA antibodies in urine after vaccination.
- Morganella morganii is a gram-negative bacterium that can cause urinary tract and bloodstream infections.
- The trial also evaluates functional antibody tests, including opsonophagocytosis and agglutination assays.
- The study is authorised but not yet reported as recruiting participants.
What is Morganella morganii (inactivated)?
Morganella morganii is a gram-negative bacterium that is a common inhabitant of the environment and the intestinal tracts of humans, mammals, and reptiles. It is also an important opportunistic pathogen, meaning it can cause infections when the body's defences are weakened. In the clinical trial listed in the EU Clinical Trials Information System, the inactivated form of this bacterium is one of 10 specified enterobacterial strains contained in StroVac, an injection suspension used for vaccination.
Inactivated bacteria are killed or rendered unable to replicate, so they cannot cause disease but can still stimulate an immune response. Morganella morganii (inactivated) is an investigational vaccine component rather than an authorised medicine in these records.
How does Morganella morganii (inactivated) work?
The vaccine approach using inactivated Morganella morganii aims to train the immune system to recognise and respond to the bacterium. The clinical trial is investigating whether vaccination with StroVac induces specific antibodies: immunoglobulin G (IgG) in blood plasma and immunoglobulin A (IgA) in urine, directed against each of the 10 bacterial strains contained in the vaccine. Antibodies are proteins made by the immune system that bind to foreign substances such as bacteria and help eliminate them.
Morganella morganii possesses several features that help it cause infection. Uropathogenic strains can produce urease, an enzyme that breaks down urea, and some strains can cause haemolysis (destruction of red blood cells) through a toxin called RTX. These properties are associated with the bacterium's ability to damage bladder cells.
Which conditions is Morganella morganii (inactivated) studied for?
- Urinary tract infection — the clinical trial investigates StroVac, which contains inactivated Morganella morganii, as a vaccination approach in people with urinary tract infections.
Beyond the vaccine trial, Morganella morganii itself is known to cause a wide range of clinical and community-acquired infections. In a retrospective study of 73 patients with Morganella morganii bacteremia (bacteria in the bloodstream), the urinary tract was the most common portal of entry, accounting for 37% of cases. Solid tumours were the most frequently encountered underlying disease.
How is Morganella morganii (inactivated) given?
Morganella morganii (inactivated) is given as part of StroVac, which is formulated as an injection suspension. The clinical trial describes the intervention as StroVac injection suspension containing inactivated germs of specified enterobacteria, including Morganella morganii. The route of administration is by injection.
What do the clinical trials show?
One clinical trial involving StroVac, which contains inactivated Morganella morganii, is registered in the EU Clinical Trials Information System. This is a Phase 3 proof-of-concept study with a planned enrolment of 20 participants. The trial is currently authorised but no results have been reported yet, so it is too early to say what the vaccine shows in terms of effectiveness.
The trial has two main objectives. First, it investigates whether an ELISA (a laboratory test that detects antibodies) is suitable for measuring IgG antibodies in blood plasma and IgA antibodies in urine after StroVac vaccination. Second, it evaluates whether three methods can detect functional antibodies — antibodies that actively help eliminate bacteria — in the blood: an opsonophagocytosis assay (OPA), an agglutination test, and a neutralisation test.
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 from before vaccination (baseline) to after vaccination (Visit 4).
What side effects are known?
The provided sources do not report side effects for Morganella morganii (inactivated) or StroVac vaccination. The clinical trial record does not include a safety outcomes section, and the supplementary sources focus on the bacterium's characteristics and clinical infections rather than vaccine-related adverse events. Therefore, no side effect information can be presented here.