# A Serological Assay for Neutralizing Antitoxin Response in Patients with Clostridioides difficile Infection (Phase II)

> **NIH NIH R44** · FZATA, INC. · 2021 · $999,996

## Abstract

Abstract
This SBIR Phase II project will support the development of an in vitro diagnostic blood test to determine
whether a person infected with Clostridioides difficile has mounted enough neutralizing antitoxin antibodies so
that they are unlikely to suffer recurrence. Antibiotic-resistant C. difficile is responsible for more than 29,000
deaths in the US each year and the infection is an urgent threat to public health worldwide. The current
standard treatment with antibiotics disrupts gut microbiota and induces high rates of recurrence, which is the
most significant issue in clinical management of the disease. C. difficile infection (CDI) is mainly caused by two
major exotoxins, and toxin-neutralizing antibodies are responsible for effective immunity. However, current
assays to measure patient antitoxin responses are based on cell-culture neutralizing bioassay that is time
consuming, laborious, and difficult to standardize, thus such bioassay is limited in research laboratories. In our
SBIR Phase I (R43AI136176) study, we successfully established a simple and rapid serological ELISA,
designated as BB-ELISA, and demonstrated that the BB-ELISA was able to measure antitoxin neutralizing
activities in CDI blood samples. Based on these promising results, we propose to standardize this novel BB-
ELISA through an experience CRO Corgenix and to collaborate with Merck to evaluate the assay for predicting
CDI disease recurrence and outcomes. The completion of this Phase II SBIR will not only validate this novel
ELISA for measuring neutralizing antibody responses in CDI patients and predicting disease outcomes, but
also pave the way toward future commercialization of this novel ELISA assay.

## Key facts

- **NIH application ID:** 10325405
- **Project number:** 2R44AI136176-02
- **Recipient organization:** FZATA, INC.
- **Principal Investigator:** Kevin W Garey
- **Activity code:** R44 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2021
- **Award amount:** $999,996
- **Award type:** 2
- **Project period:** 2018-01-20 → 2024-07-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10325405

## Citation

> US National Institutes of Health, RePORTER application 10325405, A Serological Assay for Neutralizing Antitoxin Response in Patients with Clostridioides difficile Infection (Phase II) (2R44AI136176-02). Retrieved via AI Analytics 2026-05-23 from https://api.ai-analytics.org/grant/nih/10325405. Licensed CC0.

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