The Impact of Pathogen Inactivation Technologies on Platelet Quality and Clot Formation

Shrinking donor pools and increasing clinical demand increase the attractiveness of 7-day platelet shelf-life. This can be achieved with pathogen inactivation to mitigate bacterial risk. Studies directly comparing clot formation performance in 7-day platelets prepared with different pathogen inactivation technologies (PITs) have not been conducted to date. To address this gap, we compared in vitro metabolic, functional, and clot formation parameters up to 7 days in platelets prepared with the two CE-marked PITs available on the market during the time the study was conducted.

Three identical whole-blood-derived platelet units in PAS-E/plasma were prepared using a pool-and-split approach. One split unit was treated with amotosalen/UVA (AS/UVA); the second with riboflavin/UVA-B (RB/UVA-B); the third was an untreated control. In vitro parameters and clot formation (ROTEM INTEM and EXTEM) were assessed on storage days 2, 5, and 7.

AS/UVA platelets were not significantly different from controls in most parameters. Platelets treated with RB/UVA-B showed increasing storage lesion over time. Clot formation was significantly impacted by the RB/UVA-B process, with reduced clot strength and prolonged clot formation in EXTEM and INTEM assays. Clot formation remained unaffected in the INTEM analysis and showed only minor alterations in the EXTEM analysis in AS/UVA platelets.

Platelets in PAS-E treated with different PITs have different in vitro quality and efficacy profiles. 7-Day RB/UVA-B-treated platelet concentrates (PCs) did not retain in vitro quality parameters and cannot be recommended for transfusion, whereas/UVA PCs had acceptable in vitro quality and efficacy for transfusion at both 5 and 7 days of storage.