FDA Finalises Buffy Coat System Guidance

The US Food and Drug Administration (FDA) has finalised guidance for manufacturers developing blood collection, processing and storage systems for the buffy coat method of preparing blood components for transfusion. The September 2026 final guidance was announced in the Federal Register on 17 September 2026, under docket FDA-2024-D-2732.

This is a manufacturer-facing development and submission guide. Its scope includes blood bags containing anticoagulants or additive solutions and empty bags used for platelet pooling. It is relevant to device and combination-system programmes even though the issuing centre is FDA's Center for Biologics Evaluation and Research (CBER).

Final guidance, with a defined product scope

The document finalises the October 2024 draft. FDA's notice identifies clarifications concerning overnight ambient-temperature holds, additive solutions not currently approved by FDA, and the transition to systems without di(2-ethylhexyl) phthalate (DEHP).

The guidance contains nonbinding recommendations. It does not itself approve a product, create a mandatory switch to the buffy coat method, or set an industry-wide implementation deadline. Applicable statutory and regulatory requirements still govern the submission and use of a particular system.

Two exclusions matter. The guidance does not address devices making platelet-rich plasma or similar products for therapeutic uses other than transfusion. It also does not address blood establishments using systems already approved or cleared for buffy coat preparation. The final text, Sections I and II, distinguishes development of the system from a blood establishment's subsequent use of an authorised system.

Confirm the submission pathway before designing the evidence package

Section III explains that the pathway depends on the system's composition, including whether it is an empty bag or contains anticoagulant or storage solutions. FDA recommends discussing the appropriate route with the agency. The examples include a New Drug Application (NDA), Premarket Approval (PMA), 510(k), and, for investigations, an Investigational New Drug (IND) or Investigational Device Exemption (IDE) submission.

The document therefore does not assign every buffy coat system to a single device pathway. Section IV recommends early engagement with CBER's Office of Blood Research and Review (OBRR), before submitting a drug or device application, with the meeting type selected for the pathway and development stage.

Support the proposed processing and storage claims

The recommendations make the product's proposed use conditions central to the supporting evidence:

• Separation timing: FDA recognises systems holding whole blood for up to 24 hours before separation. The separation timeframe must follow the system's directions for use, and the submission should contain data supporting the proposed interval. This is not blanket permission for every system to use an overnight hold.
• Materials and solutions: FDA supports development of systems without DEHP and introduction of additive solutions not currently approved by FDA, while encouraging discussion of the supporting data and submission. This does not constitute approval of a particular new solution.
• Product safety and performance: the recommended dossier includes design and manufacturing information, biocompatibility and toxicological assessments, extractables and leachables studies, sterilisation and endotoxin evidence, container-closure integrity and shelf-life support.
• Blood-component quality: studies should compare components produced by the buffy coat method with those from approved or cleared systems throughout storage. If platelets are pooled, evidence should represent the maximum pool size. Filter performance data are recommended where the system includes leukocyte reduction, along with appropriate clinical studies or existing clinical data supporting safety and efficacy.

Section III also gives component-specific study acceptance criteria, sample-size recommendations and provisions for justified alternatives. The appendix supplies suggested secondary in-vitro parameters. Manufacturers should use those detailed provisions when developing protocols; the general evidence categories above are not a complete test specification.

What this means for development teams

Pure Global analysis: Teams should review the final guidance before fixing the system configuration, study protocol and labelling claims. Confirming the pathway with FDA early is especially useful when a programme combines a new bag material, a different additive solution and an overnight processing claim. These decisions affect the evidence package together; supporting an individual component does not automatically support the complete proposed system.

For programmes already planned around the draft, review the final sections on materials, solutions and separation timing against the proposed instructions for use. The relevant action is a documented gap assessment and an agency discussion where needed, rather than assuming a new statutory deadline or an automatic market authorisation.

See the United States market overview for broader market-entry context.