CytoSorbents Updates U.S. FDA Regulatory Status of DrugSorb-ATR

FDA appeal decision found no issues with DrugSorb-ATR device safety but upheld the De Novo denial, and proposes a potential path forward for market authorization.

PRINCETON, N.J., Aug. 20, 2025 — CytoSorbents Corporation (NASDAQ: CTSO), a leader in the treatment of life-threatening conditions in the intensive care unit and cardiac surgery using blood purification, today updates the regulatory status of its appeal with the U.S. Food and Drug Administration (FDA) for De Novo market authorization of DrugSorb-ATR.

On August 14, 2025, the Company received an FDA appeal decision following its July 2025 in-person supervisory administrative review meeting with the FDA under 21 CFR 10.75. The appeal followed the FDA’s April 25, 2025 denial of the Company’s De Novo application for DrugSorb-ATR. In its appeal decision the FDA found no issues with device safety but upheld the prior De Novo denial, citing the need for additional information to support the Company’s requested label indication for this FDA Breakthrough Device. The Agency proactively proposed a potential path forward for market authorization and CytoSorbents continues interactive discussions with the FDA to seek further clarity on that proposal. The FDA also noted another avenue for appeal to a higher level within the Agency, specifically with the Director of the FDA’s Center for Devices and Radiologic Health (CDRH), which must be filed within 30 days of the appeal decision; the Company is currently evaluating that option.

Dr. Phillip Chan, Chief Executive Officer of CytoSorbents, said, “The path to FDA approval frequently involves sequential, collaborative discussions with the Agency to address issues that arise during the review process. Although we are disappointed that the denial decision was upheld, we believe significant progress has been made with the resolution of the majority of outstanding issues previously raised by the FDA. Importantly, the FDA affirmed no issues of device safety, establishing the De Novo standard of a favorable benefit-to-risk profile. We appreciate the Agency’s offer to find a path forward to market authorization and plan to discuss it further. We remain committed to continuing our collaborative interaction with the FDA to bring DrugSorb-ATR, an FDA Breakthrough Device, to the tens of thousands of heart attack patients in the U.S. each year who require urgent coronary artery bypass graft surgery on ticagrelor. Today, these patients in the U.S. are often forced to delay needed CABG surgery by many days or face severe perioperative bleeding. Our technology is used around the world to address this risk, and our goal is to make this therapy available to U.S. and Canadian surgeons and patients.”

About CytoSorbents Corporation (NASDAQ: CTSO)

CytoSorbents is a leader in blood purification therapies for life-threatening conditions in intensive care and cardiac surgery. Its proprietary technology uses biocompatible, highly porous polymer beads that remove toxic substances from blood by pore capture and surface adsorption. Cartridges filled with these beads are used with standard hospital blood pumps (for example dialysis, CRRT, ECMO, and heart-lung machines) where blood is circulated through the cartridge to remove toxins and then returned to the patient.

CytoSorb, the Company’s lead product, is approved in the European Union and distributed in over 70 countries, with nearly 300,000 devices used cumulatively to date. CytoSorb has received CE mark extensions and has been used for indications that include cytokine adsorption, bilirubin and myoglobin removal, and removal of certain antithrombotic drugs in cardiothoracic procedures. In the U.S. the technology received an Emergency Use Authorization for use in critically ill COVID-19 patients; CytoSorb is not yet approved or cleared in the United States for routine commercial use.

DrugSorb-ATR and regulatory status

In the U.S. and Canada CytoSorbents is developing DrugSorb-ATR, an antithrombotic removal system based on equivalent polymer technology to CytoSorb, intended to reduce perioperative bleeding in high-risk surgery due to blood-thinning drugs. DrugSorb-ATR has received two FDA Breakthrough Device designations: one for ticagrelor removal and another for removal of direct oral anticoagulants (DOACs) such as apixaban and rivaroxaban in cardiopulmonary bypass circuits during urgent cardiothoracic procedures.

The Company submitted a De Novo request to the U.S. FDA in September 2024; the submission was accepted for substantive review in October 2024. On April 25, 2025, the FDA issued a denial identifying deficiencies that must be addressed before a De Novo can be granted. The Company requested a supervisory administrative appeal under 21 CFR 10.75 and had an in-person appeal meeting with the FDA in July 2025. As noted above, the FDA’s August 14, 2025 appeal decision found no safety concerns but upheld the denial and proposed a potential path forward, which the Company is exploring through continued interaction with the Agency.

Separately, in November 2024 the Company received its MDSAP certification and submitted its Medical Device License application to Health Canada. On June 26, 2025, Health Canada issued a Notice of Refusal identifying deficiencies to be addressed before the application may be granted. The Company has filed a Level 1 Request for Reconsideration with Health Canada and, by agreement with the Medical Devices Directorate, will pursue that review following completion of its review with the U.S. FDA.

DrugSorb-ATR is not yet authorized or approved in the United States or Canada. The Company has multiple marketed products and pipeline programs based on its blood purification technology, protected by issued U.S. and international patents and pending applications.

Forward-Looking Statements

This press release contains forward-looking statements subject to risks and uncertainties. Actual results may differ materially from those projected. Factors include, but are not limited to, the Company’s ability to resolve the deficiencies identified by the FDA and Health Canada, the outcome of regulatory interactions and appeals, commercial and clinical execution, and other risks described in CytoSorbents’ SEC filings. The Company undertakes no obligation to update forward-looking statements except as required by law.

Contacts

U.S. Company Contact:
Peter J. Mariani, Chief Financial Officer
305 College Road East
Princeton, NJ 08540

Investor Relations Contact:
Aman Patel, CFA & Adanna G. Alexander, PhD
ICR Healthcare

Source: CytoSorbents Corporation