- Phase
2 studies showed the TSS1-T vaccine to be safe and effective, offering
potential preventative therapy for vulnerable groups and medical workers
- Outcome
is also a major step in the battle against MRSA infections
- Phase
3 trial preparation underway
- Staphylococcal-induced
Toxic Shock Syndrome (TSS) is a serious and life-threatening condition
affecting at risk patients, including those with compromised immunity and
premenopausal women
- Methicillin-resistant
Staphylococcus aureus
(MRSA) is a constant threat to patients and a major financial burden for
healthcare systems
The first vaccine to potentially prevent Staphylococcal-induced Toxic Shock Syndrome (TSS) has successfully completed a Phase 2 study. TSS is a life-threatening condition caused by toxins that can lead to multiple organ failure and death.
Nosocomial pathogen
Methicillin-resistant Staphylococcus
aureus (MRSA) bacteria are resistant to widely used antibiotics.
Infections with MRSA are harder to treat and therapies are more expensive as
the length of hospital stays is significantly prolonged. If the treatment does
not lead to rapid clearance of the bacterial pathogen, dangerous symptoms such
as septic or toxic shock can occur – a potentially life-threatening condition.
Researchers at Biomedical Research &
Bio-Products AG, under the direction of Prof. Dr. Martha Eibl, in cooperation
with MedUni Vienna’s Department of Clinical Pharmacology, conducted the Phase 2
clinical study. The promising results showed the TSST-1 vaccine is safe and
effective, with immunization lasting for at least two years. The results are
now subject to a peer review process, with full data to be published in
scientific journals. Preparation of a Phase 3 study is underway.
“Toxic Shock Syndrome is a serious and
sometimes life-threatening condition and is also caused by MRSA. TSS affects
vulnerable groups such as those with compromised immunity through chronic
illness, surgery or undergoing dialysis, and is also associated with
tampon use in young women. Prevention, early recognition, and treatment of MRSA
and TSS are crucial to prevent severe complications and improve outcomes,” said
Dr. Andreas Roetzer, Head of R&D for vaccines at Biomedical Research &
Bio-Products AG. “With highly encouraging data from the Phase 2 study building
on a successful Phase 1, we believe the TSST-1 vaccine could represent a real
breakthrough in protecting these groups, as well as medical workers in at-risk
settings. We look forward to publication of the full data and to moving TSST-1
into a pivotal Phase 3 trial.”
“Developed from a detoxified
staphylococcal toxin (1), the vaccine is administered intramuscularly and its
effects are similar to those of a tetanus shot,” said Prof. Dr. Bernd Jilma of
MedUni Vienna's Department of Clinical Pharmacology. “After vaccination with
TSST-1, individuals develop antibodies that are protective as germs become
dangerous. The vaccination is effective irrespective of whether or not strains
are resistant to antibiotics. A simple blood test can be used to determine
whether someone has low antibody levels, enabling people at risk to be
vaccinated preventatively.”
Staphylococci pose a substantial health
risk
Most people are affected by antibiotic
sensitive or even resistant staphylococci colonization, especially on the skin
and mucosa, but the presence of the bacteria is generally harmless and goes
unnoticed. However, in patients whose immune system is compromised, or who are
about to undergo major surgery, staphylococci can lead to serious illness.
Delayed clearance of resistant bacteria can encourage this outcome. Toxic Shock
Syndrome can also affect patients undergoing dialysis and organ transplants, as
well as those with chronic or liver diseases, and patients after heart surgery.
A successful preventative vaccine could also be used to protect medical staff.
Menstrual TSS accounts for around 50% of
cases
TSS is also associated with tampon use
in young women, which account for around 50% of all cases. The syndrome was
first described in the 1980s, with general symptoms of sepsis or blood poisoning
in young girls who had used so-called ‘super tampons’. This led to regulation
of the absorption capacity of tampons. According to a recent study in France,
the condition still has an incidence of 1/100,000 (2). According to the
Robert-Koch-Institute, the incidence in Germany in 2015 was 3 to 6 cases per
100,000 women of sexually active age (3). Hospitalization at intensive care
units, immediate shock management, and administration of antibiotics comprise
the necessary treatment.
Multicomponent vaccine to combat TSS
Researchers at Biomedical Research &
Bio-Products AG have identified a certain class of toxins which are linked to
TSS and may also play an important role in other diseases caused by
staphylococci, such as septic shock.
Detoxified variants of the medically
relevant toxins responsible for various forms of toxic shock syndrome are to be
combined into a multi-component vaccine. Studies with the multi-component
vaccine are already being planned.
Hyperimmune globulins can be used for
the treatment of TSS in both preventive (such as prior to major surgeries) and
acute (such as for burn patients) cases, similarly to traditional immunization
vaccinations for the same target groups.
