5-analyte assay reliably classifies severity of
illness, predicts mortality risk, provides insights for therapeutic
strategies.
A rapid five-biomarker assay for sepsis in
development for more than a decade classified severity of infection and
predicted mortality risk in more than 400 pediatric patients. When adapted to
mouse models, this blood test reliably predicted mortality risk and revealed
that those with a higher risk for mortality had a heavier bacterial burden that
responded to increased doses of antibiotics rather than anti-inflammatory
medications. The results, published in Science Translational Medicine, could
pave the way for new therapeutic approaches in sepsis management, according to
the study authors.
Sepsis’ heterogeneity has made it difficult for
researchers to develop new treatments for this deadly disease. However, the
novel assay Pediatric Sepsis Biomarker Risk Model, or PERSEVERE, could help
physicians pick the right dosages and drugs for patients, according to Hector
Wong, MD, director of critical care medicine at Cincinnati Children’s Hospital
Medical Center and a chief architect of the assay.
Wong and his colleagues in
their study had two major goals: to prospectively test the PERSEVERE-based
prognostic enrichment tool and to test whether PERSEVERE biomarkers were
conserved in experimental mice challenged with sepsis, Wong told. “While this is
fundamentally interesting, it also opens up many possibilities for testing
precision medicine concepts for sepsis in the preclinical setting,” Wong said of
the animal model.
PERSEVERE has been a work in progress for some time. Wong,
who presented his developing biomarker test at the Annual Scientific Meeting,
has since worked to refine the assay platform, narrowing the number of candidate
biomarkers from 80 to five. Each of these biomarkers reflects sepsis biology:
C-C chemokine ligand 3 (CCL3); interleukin 8 (IL8); heat shock protein 70 kDa 1B
(HSPA1B); granzyme B (GZMB), and matrix metallopeptidase 8 (MMP8). From this
panel, Wong’s team crafted a model that estimated 28-day mortality risk in
pediatric patients with septic shock.
PERSEVERE II, the new and improved
test, tested the blood samples of a diverse group of 461 pediatric patients aged
1 to 18 years with severe sepsis. The patients had been admitted to intensive
care units and were under care at Wong’s institution and others. Investigators
determined that the five biomarkers reliably predicted the severity of infection
and risk of death. “By demonstrating that PERSEVERE performed well during
prospective testing, we are much more confident that it is a viable clinical
tool for prognostic enrichment,” Wong said.
Adapting PERSEVERE II in mouse
models, the same biomarkers were able to predict which mice were at high or low
risk for infection. They also made an observation about treatment methods: High
doses of antibiotics proved more effective than steroid drugs in improving
survival. In both the human and mouse models, higher risk of sepsis were
associated with a higher bacterial burden, suggesting that potent antibiotic
doses could reduce death rates in patients with severe sepsis.
“This provides
a rationale to conduct a clinical trial wherein high-risk patients are
intensively monitored to optimize antibiotic dosing. This could be targeting of
higher levels of antibiotics in the bloodstream, and/or broader spectrum
antibiotics,” Wong said. Specifically selecting high-risk patients would
optimize the risk to benefit ratio of higher intensity antibiotics, he
added.
Wong and his colleagues now are refining the assay. This work “opens
up many experimental opportunities, including the ability to test whether the
PERSEVERE biomarkers are also therapeutic targets. In this way, PERSEVERE can
move beyond prognostic enrichment, toward predictive enrichment,” Wong
said.
The platform is slated for a federally funded clinical trial to test
corticosteroids as a sepsis treatment. To advance his work to the clinic, Wong
is hoping for a collaborative relationship with a biotech industry partners.
Through Innovation Ventures, Cincinnati Children’s technology commercialization
group, his team has acquired patents for the assay platform. An adult version of
PERSEVERE is also in the works.