Clinical trial and local process evaluation of an apheresis system for preparation of white cell-reduced platelet components.

BACKGROUND

A new method for the consistent preparation of white cell (WBC)-reduced plateletpheresis components, the Spectra Leukoreduction System (LRS), was evaluated by clinical trial and local process validation. The centrifuge-based system was projected to decrease the WBC content of plateletpheresis components to a level below 1 x 10(6) per unit. Phase I and II clinical trials were performed. The manufacturer's claims were then tested at the local level with an ongoing quality assurance program.

STUDY DESIGN AND METHODS

In Phase I, a cross-over analysis of five subjects compared LRS to standard plateletpheresis procedures in collection efficiency and component quality: a panel of in vitro measures was taken on Day 0 and Day 5. In Phase II, the LRS process was tested on a larger scale (n = 57; control = 58) with component transfusion. Finally, validation, determination of degree of conformance with standards, and ongoing quality control were performed locally on a newly installed instrument.

RESULTS

Phase I and II trials revealed no significant differences between LRS and control units in donor or recipient safety and comfort, platelet function and yield, or component volume. WBC per-unit values were significantly different: the LRS median per unit was 3.2 x 10(4) WBCs, versus 81.4 x 10(4) for control units. Assessment of process capability gave an estimate of 99-percent confidence that 99.5 percent of LRS units would be WBC reduced to < 1 x 10(6) WBCs. Local process validation and quality control revealed 90-percent confidence that 99 percent of the units would be WBC reduced and 99.9-percent confidence that 75 percent would exceed platelet yield standards; the process was stable over time.

CONCLUSIONS

The LRS is safe for apheresis and the component produced is safe for transfusion with platelet function and yield equivalent to controls and WBC reduction superior to controls. Local process evaluation confirmed that component quality meets the goals of the institution.