FDA has received Requests for Designation (RFD) for catheter lock / flush solutions containing an anticoagulant or an antimicrobial in a solution (e.g. water or saline solution). These catheter lock / flush solutions are intended to be used to maintain catheter patency. The RFDs requested clarification of the FDA Center with primary jurisdiction over these products, as well as the statutory provisions under which these products would be reviewed and regulated.
In these cases, FDA determined that the solution component of these products (e.g. water or saline solution) acts by physically occupying space within the catheter and exerting pressure on the patient's circulating blood. In this way, the patient's blood is prevented from back filling into the catheter and clotting. FDA concluded that in acting in this manner, the solution component of the product meets the definition of a device in that it affects the structure or function of the body, and does not achieve its primary intended purposes through chemical or metabolic action.1
FDA also determined that in these cases, the anticoagulant or antimicrobial component of the catheter lock / flush solutions was intended to affect the structure and function of the body of man by acting chemically on microorganisms and preventing thrombotic occlusions with the catheter. FDA concluded that such components meet the definition of a drug in that they are intended to affect the structure or function of the body of man.2
For these reasons, FDA concluded that the catheter lock / flush solutions described in these RFDs consisting of a solution (e.g. water or saline solution) and an anticoagulant or antibiotic are combination products within the meaning of section 503(g) of the Federal Food, Drug, and Cosmetic Act (21 U.S.C. § 353(g)). Accordingly, review responsibility for these products was assigned based on the Agency's determination of the products' primary mode of action (PMOA). (Section 503(g)(1) of the Act, 21 U.S.C. § 353(g)(1); and 21 CFR § 3.4)
FDA determined that the PMOA of these catheter lock / flush solutions in maintaining catheter patency was attributable to the device component's role in occupying space and applying pressure within the catheter. FDA also concluded that the drug component of the combination product plays a secondary role by, for example, chemically acting on microorganisms and/or preventing thrombotic occlusions within the catheter.
Therefore, the Agency assigned these drug - device combination catheter lock / flush solutions to the Center for Devices and Radiological Health (CDRH) for review and regulation under the device provisions of the Act. The Agency stated that the adverse event reporting requirements applicable to devices (21 CFR 803) would apply. For information about applicable good manufacturing practices, FDA suggested looking at its draft guidance titled "Current Good Manufacturing Practice for Combination Products."
Sponsors wishing to discuss the regulation of a particular combination drug - device catheter lock / flush solution may contact the Office of Combination Products at 301-796-8930. Alternatively, sponsors may contact CDRH's Division of Anesthesiology, General Hospital, Infection Control, and Dental Devices, at 301-796-5580.