# Rho GTPase inhibitor for refrigerated platelet storage

> **NIH NIH R44** · OGB4 INC · 2024 · $1,188,244

## Abstract

SUMMARY
The use of platelet transfusions has increased dramatically since 1980s, but a safe, long-term platelet storage
method remains missing. Current practice has platelets stored at 20 to 24°C after preparation, which has a
limited lifetime up to 5 days primarily due to concerns about bacterial contamination, because cold storage of
platelets results in complex molecular lesions that are recognized by host macrophages and hepatocyte
counterreceptors, leading to phagocytosis and clearance upon transfusion. In prior NIH SBIR phase 1 funded
studies, we demonstrate functionally that murine, human and Rhesus-macaque washed platelets, when stored
in refrigerated conditions for 7-14 days in the presence of a reversible RhoA GTPase inhibitor, G04, can fully
maintain function to a level like that of room-temperature stored platelets. We hypothesize that reversible
inhibition of RhoA via the G04 pharmacologic inhibitor can be translated to a new regimen for safe, cost-efficient,
and fully functional long-term storage of platelets in refrigeration. This project will develop our product, the RhoA
inhibitor S-G04, an enantiomer of G04, in a Platelet Additive Solution contained in a medically available bag, for
human platelet cold storage up to 14 days. Based on a previous discussion with the US Food and Drug
Administration (FDA), we aim to assess the pharmacokinetics and ADME of S-G04 in our product and to
determine the GLP stability and safety of S-G04 in FDA IND-enabling studies. The deliverables will include an
established safety and efficacy of this product in a commercially available platelet storage PAS/bag, and that
this revolutionary technology can be available to all blood centers/hospitals needing PLT transfusion as a single
inventory, like that for plasma and red blood cell supplies.

## Key facts

- **NIH application ID:** 10920423
- **Project number:** 5R44HL123103-03
- **Recipient organization:** OGB4 INC
- **Principal Investigator:** Jose A. Cancelas
- **Activity code:** R44 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2024
- **Award amount:** $1,188,244
- **Award type:** 5
- **Project period:** 2014-08-01 → 2025-08-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10920423

## Citation

> US National Institutes of Health, RePORTER application 10920423, Rho GTPase inhibitor for refrigerated platelet storage (5R44HL123103-03). Retrieved via AI Analytics 2026-05-25 from https://api.ai-analytics.org/grant/nih/10920423. Licensed CC0.

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