Evaluation of processing characteristics of photochemically treated pooled platelets: target requirements for the...

To ensure good performance of pathogen inactivation with the INTERCEPT blood system, specific target requirements must be met for platelet dose, volume, plasma content and residual red blood cells (RBCs) prior to photochemical treatment (PCT). A two-arm in vitro study was conducted to compare quality parameters of pooled platelet concentrates (PCs), either treated (test units) or nontreated (control units). PCs meeting European requirements were evaluated with reference to their compliance with INTERCEPT guard bands. Of 50 PCs (25 tests and 25 controls) meeting European quality requirements, 24% (three test and three controls units) did not reach INTERCEPT requirements, particularly in terms of sufficient volumes and RBC contamination. The buffy-coat optimization procedure assessed prior to this study ensured plasma contents well within target limits of 30 to 45%. Due to PCT-related in-process loss of 11% in volume (34.38 +/- 3.94) and in platelet dose (0.41 +/- 0.14), the mean platelet dose was significantly (P < 0.001) lower in test units: 3.1 +/- 0.3 versus 3.6 +/- 0.4 x 10(11). After treatment, six of the overall 25 test units (25%) would not have met the European guideline for platelet dose (3.0 x 10(11)). Before implementation of techniques for pathogen reduction, each centre should optimize processing steps during a validation procedure to ensure PC complying with INTERCEPT targets before and European targets after treatment. Besides buffy-coat optimization for sufficient plasma reduction, centrifugation profiles need to be optimized as well to prevent PC with low volumes and, in particular, with higher than acceptable RBC contamination.