Nationwide Implementation of Pathogen Inactivation for All Platelet Concentrates in Switzerland

Platelet Additive Solutions and Pathogen Reduction Impact on Transfusion Safety, Patient Management and Platelet Supply

Since 1998, leuko-reduction is used in France for all platelet concentrates (PCs), apheresis-derived (APCs) and pooled whole blood-derived buffy-coats (BCPCs). Platelet additive solutions (PAS), introduced in 2005, accounted for over 80% of the platelet supply from 2011 to 2017. The Intercept pathogen reduction technology (PR), started in a pilot study in 2007, was generalized in 2018. Between 2007 and 2021, the use of BCPCs increased steadily from 23% to 70% of the supply. Objectives: to analyze the impact of these modifications on adverse transfusion reactions (ATRs), patient management and blood transfusion organization. Results: The overall incidence of ATRs /105 PCs is significantly lower with PAS- and PR-PCs as compared to PCs in plasma (PL), with the decreasing hierarchy PL > PAS > PR. PAS- and PR-PCs lead to significantly lower incidences of allergy and alloimmunization to RBC antigens (RC-AI) ATRs. The incidence of bacteria transmission (TTBI) is significantly reduced by 95% with PR-PCs. APC-related ATR incidence is significantly higher than BCPC for allergy (+233%), TTBI (+100%), APTR (+75%), Major-ABO-II (+65%), HLA/HPA-AI (+38%), FNHTR (+22%), and life-threatening ATRs (+106%). A single diagnosis is significantly less associated with APCs: RC-AI (-47%). The generalization of PR-PCs, which exhibit a lower platelet content than PAS- and PL-PCs, is associated with a significant 9% decrease in the ATR incidence per PC, a 13% increase in the number of PCs transfused per patient, and a nonsignificant 3% increase in the ATR incidence per patient. The outdated PCs percentage declined significantly from 3.7% to 1.7%.

Introduction of 7-day amotosalen/ultraviolet A light pathogen-reduced platelets in Honduras: Impact on platelet availability in a lower middle-income country

BACKGROUND AND OBJECTIVES

Honduras became the first lower middle-income country (LMIC) to adopt amotosalen/UVA pathogen-reduced (PR) platelet concentrates (PCs) as a national platelet safety measure in 2018. The Honduran Red Cross (HRC) produces ~70% of the national platelet supply using the platelet-rich plasma (PRP) method. Between 2015 and 2018, PCs were screened with bacterial culture and issued as individual, non-pooled PRP units with weight-based dosing and 5-day shelf-life. PR PCs were produced in six-PRP pools with a standardized dose (≥3.0 × 1011), no bacterial screening and 7-day shelf-life. Gamma irradiation and leukoreduction were not used.

MATERIALS AND METHODS

PC production and distribution data were retrospectively analysed in two periods. Period 1 (P1) included 3 years of PRP PCs and a transition year (2015-18). Period 2 (P2) included 5 years of PR PCs (2019-23). PC doses were standardized to an equivalent adult dose for both periods. Descriptive statistics were calculated.

RESULTS

HRC produced 10% more PC doses per year on average in P2 compared to P1. Mean annual waste at HRC declined from 23.9% in P1 to 1.1% in P2. Two urban regions consumed 96% of PC doses in P1 and 88.3% in P2. PC distributions increased in 14/18 regions.

CONCLUSION

Standardized dosage, PR and 7-day shelf-life increased PC availability, reduced waste, eliminated bacterial screening and avoided additional costs for arboviral testing, leukoreduction and irradiation. Access to PC transfusion remains limited in Honduras; however, the conversion to pooled PR PCs illustrates the potential to sustainably expand PC distribution in an LMIC.

Platelet Storage-Problems, Improvements, and New Perspectives

Platelet transfusions are routine procedures in clinical treatment aimed at preventing bleeding in critically ill patients, including those with cancer, undergoing surgery, or experiencing trauma. However, platelets are susceptible blood cells that require specific storage conditions. The availability of platelet concentrates is limited to five days due to various factors, including the risk of bacterial contamination and the occurrence of physical and functional changes known as platelet storage lesions. In this article, the problems related to platelet storage lesions are categorized into four groups depending on research areas: storage conditions, additive solutions, new testing methods for platelets (proteomic and metabolomic analysis), and extensive data modeling of platelet production (mathematical modeling, statistical analysis, and artificial intelligence). This article provides extensive information on the challenges, potential improvements, and novel perspectives regarding platelet storage.

Transfusion safety: Is there a difference between reported reactions in low-to-middle income and high-income countries?

BACKGROUND AND OBJECTIVES

Transfusion safety may be becoming dependent on the financial resources made available for transfusion structures and may vary between high-income countries (HIC) and low-to-middle-income countries (LMIC). To assess whether there is a difference in the reported TR between these two groups of countries, we examined TR reported in Tunis the capital of Tunisia, a LMIC, and compared their frequency with reported TR in HIC.

MATERIALS AND METHODS

Data of TR were collected from transfusion incident report (TIR) forms declared by healthcare facilities in Tunis between 2015 and 2019. They were analysed and compared to reported TR in France (ANSM) and UK (SHOT).

RESULTS

The incidence of TR was 70.6/100 000 blood components (BP) issued. A third of TR (36.8%) occurred at night. Febrile non-hemolytic transfusion reactions (43.7%) and allergic reactions (35%) were the most reported TR respectively 22.4/100 000 BP and 17.9/100 000 BP. The rate of ABO incompatibilities was 1.96/100 000 red blood cell units (RBC): they were all caused by human error. The rates of TRALI, TACO and bacterial contaminations were respectively 1.26/100 000 BP, 1.4/100 000 RBC and 0.7/100 000 BP.

CONCLUSION

While advanced technologies applied to transfusion have improved transfusion safety, this study shows that their impact has been relatively minor, as reported TR in LMIC are still comparable to those in HIC. ABO-incompatibilities are still higher in LMIC: this should be addressed by reinforcing the training of all healthcare personnel involved in transfusion medicine.

Health Economic Aspects of Platelet Concentrates: Comparing Cost and Reimbursement of Pathogen Inactivated and Conventional Platelet Concentrates in a German Comprehensive Cancer Center

INTRODUCTION

Pathogen inactivation (PI) utilizing amotosalen and UVA light (INTERCEPT® Blood System) is a well-established method for the production of safer platelet concentrates (PCs). While many studies describe clinical and logistical benefits of PI, the implications and potential challenges from a hospital management perspective have not yet been analyzed - health economic analyses considering reimbursement of PI are lacking. The objective of this analysis was to examine the real-life inpatient treatment costs from a hospital perspective and to assess the economic impact of PI-PC versus conventional PC (CONV-PC) administration in Germany.

METHODS

Real-life cost data for inpatient cancer cases from 2020 of the University Hospital Cologne were identified by operating and procedure codes. The German diagnosis-related groups, extra fees, case mix index (CMI), length of stay (LOS), and average resource consumption of PC were evaluated from a micro-management perspective. The potential economic impact of implementing PI-treated PCs was modeled retrospectively.

RESULTS

In total, 951 inpatient cases were analyzed (CMI [median 4.7-9.9], LOS [median 26 days], number of cases in intensive care units [38%]). The median DRG fee was between EUR 13,800 and EUR 26,400. According to our model, the use of PI-PC compared to CONV-PC would result in savings between EUR 184 and EUR 306 per case.

CONCLUSION

From a hospital management perspective, oncological cases requiring PC transfusion are associated with a high CMI (reimbursement per DRG flat fee) and moderate costs with sufficient add-on payment for PI on a case level. Investment and process costs for PI implementation can be analyzed for site-specific scenarios.

Emerging Pathogen Threats in Transfusion Medicine: Improving Safety and Confidence with Pathogen Reduction Technologies

Emerging infectious disease threats are becoming more frequent due to various social, political, and geographical pressures, including increased human-animal contact, global trade, transportation, and changing climate conditions. Since blood products for transfusion are derived from donated blood from the general population, emerging agents spread by blood contact or the transfusion of blood products are also a potential risk. Blood transfusions are essential in treating patients with anemia, blood loss, and other medical conditions. However, these lifesaving procedures can contribute to infectious disease transmission, particularly to vulnerable populations. New methods have been implemented on a global basis for the prevention of transfusion transmissions via plasma, platelets, and whole blood products. Implementing proactive pathogen reduction methods may reduce the likelihood of disease transmission via blood transfusions, even for newly emerging agents whose transmissibility and susceptibility are still being evaluated as they emerge. In this review, we consider the Mirasol PRT system for blood safety, which is based on a photochemical method involving riboflavin and UV light. We provide examples of how emerging threats, such as Ebola, SARS-CoV-2, hepatitis E, mpox and other agents, have been evaluated in real time regarding effectiveness of this method in reducing the likelihood of disease transmission via transfusions.

Longitudinal analysis of annual national hemovigilance data to assess pathogen reduced platelet transfusion trends during conversion to routine universal clinical use and 7-day storage

BACKGROUND

France converted to universal pathogen reduced (PR; amotosalen/UVA) platelets in 2017 and extended platelet component (PC) shelf-life from 5- to 7-days in 2018 and 2019. Annual national hemovigilance (HV) reports characterized longitudinal PC utilization and safety over 11 years, including several years prior to PR adoption as the national standard of care.

METHODS

Data were extracted from published annual HV reports. Apheresis and pooled buffy coat [BC] PC use was compared. Transfusion reactions (TRs) were stratified by type, severity, and causality. Trends were assessed for three periods: Baseline (2010-14; ~7% PR), Period 1 ([P1] 2015-17; 8%-21% PR), and Period 2 ([P2] 2018-20; 100% PR).

RESULTS

PC use increased by 19.1% between 2010 and 2020. Pooled BC PC production increased from 38.8% to 68.2% of total PCs. Annual changes in PCs issued averaged 2.4% per year at baseline, -0.02% (P1) and 2.8% (P2). The increase in P2 coincided with a reduction in the target platelet dose and extension to 7-day storage. Allergic reactions, alloimmunization, febrile non-hemolytic TRs, immunologic incompatibility, and ineffective transfusions accounted for >90% of TRs. Overall, TR incidence per 100,000 PCs issued declined from 527.9 (2010) to 345.7 (2020). Severe TR rates declined 34.8% between P1-P2. Forty-six transfusion-transmitted bacterial infections (TTBI) were associated with conventional PCs during baseline and P1. No TTBI were associated with amotosalen/UVA PCs. Infections with Hepatitis E (HEV) a non-enveloped virus resistant to PR, were reported in all periods.

DISCUSSION

Longitudinal HV analysis demonstrated stable PC utilization trends with reduced patient risk during conversion to universal 7-day amotosalen/UVA PCs.

Platelet transfusion in adults: An update

Many patients worldwide receive platelet components (PCs) through the transfusion of diverse types of blood components. PC transfusions are essential for the treatment of central thrombocytopenia of diverse causes, and such treatment is beneficial in patients at risk of severe bleeding. PC transfusions account for almost 10% of all the blood components supplied by blood services, but they are associated with about 3.25 times as many severe reactions (attributable to transfusion) than red blood cell transfusions after stringent in-process leukoreduction to less than 10⁶ residual cells per blood component. PCs are not homogeneous, due to the considerable differences between donors. Furthermore, the modes of PC collection and preparation, the safety precautions taken to limit either the most common (allergic-type reactions and febrile non-hemolytic reactions) or the most severe (bacterial contamination, pulmonary lesions) adverse reactions, and storage and conservation methods can all result in so-called PC "storage lesions". Some storage lesions affect PC quality, with implications for patient outcome. Good transfusion practices should result in higher levels of platelet recovery and efficacy, and lower complication rates. These practices include a matching of tissue ABH antigens whenever possible, and of platelet HLA (and, to a lesser extent, HPA) antigens in immunization situations. This review provides an overview of all the available information relating to platelet transfusion, from donor and donation to bedside transfusion, and considers the impact of the measures applied to increase transfusion efficacy while improving safety and preventing transfusion inefficacy and refractoriness. It also considers alternatives to platelet component (PC) transfusion.

Pathogen inactivation treatment of triple-dose apheresis platelets with amotosalen and ultraviolet a light

BACKGROUND

A triple storage (TS) set allows for pathogen inactivation (PI) treatment of triple-dose apheresis platelet products with amotosalen + UVA. We evaluated the quality and metabolic parameters of platelet concentrates (PCs) pathogen inactivated and stored for 7 days.

MATERIALS AND METHODS

Twelve triple-dose products collected with two different apheresis platforms were treated with amotosalen+UVA. Products were split into three single-dose units. Testing was made pretreatment, after splitting, at days 5 and 7 of storage.

RESULTS

Single-dose PI PCs had a mean platelet content of 2.89 ± 0.35 x 10¹¹ . From baseline to day 7, pH remained stable (7.1 ± 0.1 vs. 7.0 ± 0.1), pO₂ increased (11.3 ± 2.4 vs. 18.3 ± 3.5 kPa) as did LDH (201 ± 119 vs. 324 ± 203 U/L) and lactate (3.6 ± 1.7 vs. 12.1 ± 1.5 mmol/L) (all p < 0.01); pCO₂ decreased (4.1 ± 0.8 vs. 1.5 ± 0.7 mmHg; p < 0.01) and so did bicarbonate (6.6 ± 1.1 vs. 2.5 ± 1.4 mmol/L), glucose (5.6 ± 1.2 vs. 0.4 ± 0.4 mmol/L) and ATP (3.4 ± 0.9 vs. 2.5 ± 1.4 nmol/10⁸ platelets) (all p < 0.05).

CONCLUSION

Triple-dose PCs processed with the TS sets fulfilled the quality requirements and displayed metabolic changes of expected extent during 7-day storage.

Implementation strategy for complete pathogen reduction technology treated apheresis platelet inventory

BACKGROUND

Bacterial contamination in platelets remain a major public health concern, which prompted the US Food and Drug Administration guidance for bacterial contamination mitigation. Pathogen reduction technology (PRT) is one mitigation strategy that has shown success in Europe over the last decade. Therefore, our center sought to transition from a dual system of bacterial culturing (BacT) and PRT to full PRT.

METHODS

A 1 month pilot study was conducted to simulate 100% PRT conditions. Our center also collected baseline data on key platelet production metrics in the 4 months prior to 100% PRT and compared it to the 4 months post-implementation.

RESULTS

The pilot study showed no statistical differences in split rate, proportion of low-yield products, or proportion of single, double, and triple collections. The only observed difference was an 11 min increase in the average duration of double collections. Our baseline versus post-implementation monitoring showed no difference in split rate, discard rate, percentage of low-yield units, and average yield of low yield units. Statistical differences were detected in the proportion of single, double, and triple collections, as well as the average yield of full dose products. Roughly 20% of our inventory consisted of low-yield products.

DISCUSSION

With suitable mitigation strategies, transitioning to a full PRT inventory may result in higher net margins while not adversely affecting overall platelet production. A pilot study is a good way to project potential effects of switching from a dual BacT and PRT inventory to full PRT, and can be adopted by other centers aiming to make the transition.

Association of Staphylococcus aureus in platelet concentrates with skin diseases in blood donors: Limitations of cultural bacterial screening

BACKGROUND

Bacterial contamination in platelet concentrates (PCs) is a major problem in transfusion medicine. Contamination with Staphylococcus aureus is occasionally missed, even with cultural screening.

STUDY DESIGN AND METHODS

Donors implicated in S. aureus-contaminated PC were followed up. Skin and nasal swab specimens from six donors and S. aureus isolated from PCs related to these donors were subjected to multilocus sequence typing (MLST) and pulsed-field gel electrophoresis (PFGE) to determine the identity of bacteria. To evaluate the validity of the screening method using BacT/ALERT 3D, we spiked S. aureus and three other bacterial species as comparisons into PCs and investigated their growth pattern.

RESULTS

S. aureus was isolated from all nasal specimens and from the arm skin specimens of three donors with atopic dermatitis. In all cases, the S. aureus strains isolated from the PC and those from the nasal and skin specimens of the same donor showed concordant results using MLST and PFGE. In the spiking study, S. aureus showed irregular detectability over 24 to 48 h post-spike periods, whereas the three other bacterial species were detected in all culture bottles after a 24-h post-spike period.

DISCUSSION

The strain identity of S. aureus between donor and PC suggests that the contaminants were derived from those colonized in the donor. Furthermore, S. aureus yielded false-negative results using BacT/ALERT 3D.

Platelet Transfusion-Insights from Current Practice to Future Development

Since the late sixties, therapeutic or prophylactic platelet transfusion has been used to relieve hemorrhagic complications of patients with, e.g., thrombocytopenia, platelet dysfunction, and injuries, and is an essential part of the supportive care in high dose chemotherapy. Current and upcoming advances will significantly affect present standards. We focus on specific issues, including the comparison of buffy-coat (BPC) and apheresis platelet concentrates (APC); plasma additive solutions (PAS); further measures for improvement of platelet storage quality; pathogen inactivation; and cold storage of platelets. The objective of this article is to give insights from current practice to future development on platelet transfusion, focusing on these selected issues, which have a potentially major impact on forthcoming guidelines.

Transfusion-related adverse reactions: Data from the National Healthcare Safety Network Hemovigilance Module - United States, 2013-2018

BACKGROUND

Despite current blood safety measures, transfusion recipients can experience transfusion-related adverse reactions. Monitoring these reactions can aid in understanding the effectiveness of current transfusion safety measures. Data from the National Healthcare Safety Network Hemovigilance Module were used to quantify adverse reaction risk.

METHODS

Facilities reporting at least one month of transfused blood components and transfusion-related adverse reactions during January 2013-December 2018 were included. Adverse reaction rates (number per 100,000 components transfused) were calculated for transfused components stratified by component type, collection, and modification methods.

RESULTS

During 2013-2018, 201 facilities reported 18,308 transfusion-related adverse reactions among 8.34 million blood components transfused (220/100,000). Adverse reactions were higher among apheresis (486/100,000) and pathogen-reduced platelets (579/100,000) than apheresis red blood cells (197/100,000). Allergic reactions (41%) were most common. There were 23 fatalities and 9% of all adverse reactions were serious (severe, life-threatening, or fatal). Reactions involving pulmonary complications (transfusion-associated circulatory overload, transfusion-related acute lung injury and transfusion-associated dyspnea) accounted for 35% of serious reactions but 65% of fatalities. Most (76%) of the 37 transfusion-transmitted infections were serious; none involved pathogen-reduced components.

CONCLUSIONS

One in 455 blood components transfused was associated with an adverse reaction although the risk of serious reactions (1 in 6224) or transfusion-transmitted infections (1 in 225,440) was lower. Some serious reactions identified were preventable, suggesting additional safety measures may be beneficial. Higher reaction rates identified among pathogen-reduced platelets require further study. These findings highlight the importance of monitoring reactions through national hemovigilance to inform current safety measures and the need for strategies to increase healthcare facility participation.

Efficacy of UVC-treated, pathogen-reduced platelets versus untreated platelets: a randomized controlled non-inferiority trial

Pathogen reduction (PR) technologies for blood components have been established to reduce the residual risk of known and emerging infectious agents. THERAFLEX UV-Platelets, a novel ultraviolet C (UVC) light-based PR technology for platelet concentrates, works without photoactive substances. This randomized, controlled, double-blind, multicenter, non-inferiority trial was designed to compare the efficacy and safety of UVC-treated platelets to that of untreated platelets in thrombocytopenic patients with hematologic-oncologic diseases. The primary objective was to determine non-inferiority of UVC-treated platelets, assessed by the 1-hour corrected count increment (CCI) in up to eight per-protocol platelet transfusion episodes. Analysis of the 171 eligible patients showed that the defined non-inferiority margin of 30% of UVC-treated platelets was narrowly missed as the mean differences in 1-hour CCI between standard platelets versus UVC-treated platelets for intention-to-treat and per-protocol analyses were 18.2% (95% Confidence Interval [CI]: 6.4-30.1) and 18.7% (95% CI: 6.3-31.1), respectively. In comparison to the control, the UVC group had a 19.2% lower mean 24-hour CCI and was treated with an about 25% higher number of platelet units, but the average number of days to the next platelet transfusion did not differ significantly between both treatment groups. The frequency of low-grade adverse events was slightly higher in the UVC group and the frequencies of refractoriness to platelet transfusion, platelet alloimmunization, severe bleeding events, and red blood cell transfusions were comparable between groups. Our study suggests that transfusion of pathogen-reduced platelets produced with the UVC technology is safe but non-inferiority was not demonstrated. (clinicaltrials gov. Identifier: DRKS00011156).

Evaluation of riboflavin and ultraviolet light treatment against Klebsiella pneumoniae in whole blood-derived platelets: A pilot study

BACKGROUND

Bacterial contamination of platelet concentrates (PCs) is the predominant cause of infectious transfusion reactions. The Pathogen Inactivation Mirasol system was implemented at the King Faisal Specialist Hospital (Saudi Arabia) to reduce the risk of transfusing contaminated PCs. This pilot study evaluated the effectiveness of Mirasol against Klebsiella pneumoniae, a pathogen associated with transfusion reactions, in whole blood-derived PCs.

STUDY DESIGN AND METHODS

Whole blood (WB) units inoculated with one of six K. pneumoniae strains (five clinical isolates and ATCC-700603) at a concentration of 3-38 CFU/unit, were processed using the platelet-rich plasma (PRP) method. Each spiked PC was pooled with four unspiked units. The pooled PC was split into three Mirasol storage bags: an untreated unit (control), and two units treated with Mirasol at 26 and 32 h post-WB collection, respectively. PC samples obtained before and after Mirasol treatment were used for BacT/ALERT cultures and determination of bacteria quantification. Each experiment was repeated three independent times.

RESULTS

Five strains were detected prior to PC treatment (24 h post-WB spiking), while one clinical isolate was not detected. Mirasol treatment after 26 h of WB collection resulted in complete inactivation of all K. pneumoniae strains. However, treatment 32 h post-WB collection resulted in the breakthrough of one clinical isolate in two of the three replicates with ~7.8 log₁₀ CFU/unit detected on day 5 of PC storage.

CONCLUSION

Delayed Mirasol treatment from 26 to 32 h post-WB collection, resulted in one breakthrough. These results highlight the importance of minimizing the time between WB collection and PI treatment.

Effects of Intercept pathogen reduction treatment on extended cold storage of apheresis platelets

BACKGROUND

Platelets pose the greatest transfusion-transmitted infectious risk among blood products. Refrigeration of platelets can mitigate bacterial contamination and extend platelet shelf life. Implementation of pathogen reduction technologies (PRTs) at blood banks has become increasingly popular to protect against emerging and reemerging infectious diseases. In this study, we sought to evaluate the effects of Intercept PRT on platelets collected on different platforms and cold-stored for up to 21 days in plasma and platelet additive solution (PAS).

METHODS

Double-dose apheresis platelets were collected with use of a Trima or Amicus system into either 100% plasma or 65% InterSol PAS/35% plasma and split equally between two bags. One bag served as control, while the other received Intercept PRT treatment. Bags were stored unagitated in the cold and evaluated on Days 1, 7, 14, and 21 to assess platelet metabolism, activation, aggregation, and clot formation and retraction.

RESULTS

By Day 14 of storage, lactate levels reached approximately 13 mmol/L for all samples irrespective of Intercept treatment. Mean clot firmness dropped from the 62.2- to 67.5-mm range (Day 1) to the 28.4- to 51.3-mm range (Day 21), with no differences observed between groups. Clot weights of Intercept-treated Trima/plasma samples were significantly higher than control by Day 14 of storage (P = .004), indicating a reduced clot retraction function. Intercept treatment caused a higher incidence of plasma membrane breakdown in plasma-stored platelets (P = .0013; Trima/plasma Day 14 Control vs Intercept).

CONCLUSIONS

Intercept treatment of platelets and subsequent cold storage, in plasma or PAS, results in comparable platelet metabolism platelets for up to 14 days of storage but altered clotting dynamics. Pathogen-reduced platelets with an extended shelf life would be beneficial for the deployed setting and would greatly impact transfusion practice among civilian transfusion centers.

Pathogen reduction of double-dose platelet concentrates from pools of eight buffy coats: Product quality, safety, and economic aspects

Background

Pathogen reduction (PR) of platelet concentrates (PCs) contributes to the safety of platelet (PLT) transfusion by reducing the risk of transfusion‐transmitted infections and transfusion‐associated graft‐versus‐host disease. In vitro quality of pathogen‐reduced double‐dose PC (PR‐PC) made of eight whole blood (WB)‐derived buffy coats (BCs) were evaluated.

Methods

Eight small‐volume WB BCs from donors with at least 200 × 10⁹ PLT/L were pooled with an additive solution to produce double‐dose PCs (DD‐PCs), which were treated with amotosalen/ultraviolet A light in a dual storage processing set, yielding 2 units of PR‐PC. Quality controls were undertaken as per European Directive for the Quality of Medicines (EDQM) guidelines. PLT recovery rates were measured. Production costs and savings were compared over the 3 years before and after PR implementation.

Results

In the pre‐PR period, 19 666 PCs were produced, compared to 17 307 PCs in the PR period. Single BC in the PR period had 41 ± 2 mL, hematocrit 0.39 ± 0.04 and 1.06 ± 0.18 × 10¹¹ PLTs, and showed a recovery of 91% ± 8%. After pooling, separation, PR treatment of DD‐PC, and splitting, each single PC had 189 ± 6 mL with 2.52 ± 0.34 × 10¹¹ PLTs, compared to 2.48 ± 0.40 in the pre‐PR period. The PLT recovery rate after PR was 87% ± 14%. EDQM requirements were met. An increase of about €12 (+7.5%) per PC from the pre‐PR to the PR period was identified.

Conclusion

A new production method resulting in two PR‐PCs made from pools of 8 BCs with use of one PR set was successfully introduced, and our experience of nearly 3 years demonstrated the high efficacy and in vitro quality of the PR‐PCs obtained.

Platelets treated with pathogen reduction technology: current status and future direction

Allogeneic platelets collected for transfusion treated with pathogen reduction technology (PRT), which has been available in some countries for more than a decade, are now increasingly available in the United States (US). The implementation of PRT-treated platelets, also known as pathogen-reduced platelets (PRPs), has been spurred by the need to further decrease the risk of sepsis associated with bacterial contamination coupled with the potential of this technology to reduce the risk of infections due to already recognized, new, and emerging infectious agents. This article will review available PRP products, examine their benefits, highlight unresolved questions surrounding this technology, and summarize pivotal research studies that have compared transfusion outcomes (largely in adult patients) for PRPs with non-PRT-treated conventional platelets (CPs). In addition, studies describing the use of PRPs in pediatric patients and work done on the association between PRPs and HLA alloimmunization are discussed. As new data emerge, it is critical to re-evaluate the risks and benefits of existing PRPs and newer technologies and reassess the financial implications of adopting PRPs to guide our decision-making process for the implementation of transfusing PRPs.

Metabolomics study of platelet concentrates photochemically treated with amotosalen and UVA light for pathogen inactivation

BACKGROUND

The risk of bacterial contamination and the deterioration of platelet (PLT) quality limit the shelf-life of platelet concentrates (PCs). The INTERCEPT pathogen inactivation system reduces the risk of pathogen transmission by inhibiting nucleic acid replication using a combination of a photo-reactive compound and UVA illumination. The goal of this study was to investigate the effects the INTERCEPT system has on the PLT metabolome and metabolic activity.

STUDY DESIGN AND METHODS

Paired units of buffy coat-derived PCs were generated using a pool and split strategy (n = 8). The paired PCs were either treated with the INTERCEPT system or left untreated. Samples were collected on Days 1, 2, 4, and 7 of storage. Ultra-performance chromatography coupled with time-of-flight mass spectrometry was used to analyze the extra- and intracellular metabolomes. Constraint-based metabolic modeling was then used to predict the metabolic activity of the stored PLTs.

RESULTS

A relatively large number of metabolites in the extracellular environment were depleted during the processing steps of the INTERCEPT system, in particular, metabolites with hydrophobic functional groups, including acylcarnitines and lysophosphatidylcholines. In the intracellular environment, alterations in glucose and glycerophospholipid metabolism and decreased levels of 2-hydroxyglutarate were observed following the INTERCEPT treatment. Untargeted metabolomics analysis revealed residual amotosalen dimers present in the treated PCs. Systems-level analysis of PLT metabolism indicated that the INTERCEPT system does not have a significant impact on the PLT energy metabolism and nutrient utilization.

CONCLUSIONS

The INTERCEPT system significantly alters the metabolome of the stored PCs without significantly influencing PLT energy metabolism.

Amotosalen and ultraviolet A light efficiently inactivate MERS-coronavirus in human platelet concentrates

Objective

This study aimed to assess the efficacy of the INTERCEPT™ Blood System [amotosalen/ultraviolet A (UVA) light] to reduce the risk of Middle East respiratory syndrome‐Coronavirus (MERS‐CoV) transmission by human platelet concentrates.

Background

Since 2012, more than 2425 MERS‐CoV human cases have been reported in 27 countries. The infection causes acute respiratory disease, which was responsible for 838 deaths in these countries, mainly in Saudi Arabia. Viral genomic RNA was detected in whole blood, serum and plasma of infected patients, raising concerns of the safety of blood supplies, especially in endemic areas.

Methods

Four apheresis platelet units in 100% plasma were inoculated with a clinical MERS‐CoV isolate. Spiked units were then treated with amotosalen/UVA to inactivate MERS‐CoV. Infectious and genomic viral titres were quantified by plaque assay and quantitative real‐time reverse transcription polymerase chain reaction (RT‐qPCR). Inactivated samples were successively passaged thrice on Vero E6 cells to exclude the presence of residual replication‐competent viral particles in inactivated platelets.

Results

Complete inactivation of MERS‐CoV in spiked platelet units was achieved by treatment with Amotosalen/UVA light with a mean log reduction of 4·48 ± 0·3. Passaging of the inactivated samples in Vero E6 showed no viral replication even after nine days of incubation and three passages. Viral genomic RNA titration in inactivated samples showed titres comparable to those in pre‐treatment samples.

Conclusion

Amotosalen and UVA light treatment of MERS‐CoV‐spiked platelet concentrates efficiently and completely inactivated MERS‐CoV infectivity (>4 logs), suggesting that such treatment could minimise the risk of transfusion‐related MERS‐CoV transmission.

Pathogen reduction of blood components during outbreaks of infectious diseases in the European Union: an expert opinion from the European Centre for Disease Prevention and Control consultation meeting

Pathogen reduction (PR) of selected blood components is a technology that has been adopted in practice in various ways. Although they offer great advantages in improving the safety of the blood supply, these technologies have limitations which hinder their broader use, e.g. increased costs. In this context, the European Centre for Disease Prevention and Control (ECDC), in co-operation with the Italian National Blood Centre, organised an expert consultation meeting to discuss the potential role of pathogen reduction technologies (PRT) as a blood safety intervention during outbreaks of infectious diseases for which (in most cases) laboratory screening of blood donations is not available. The meeting brought together 26 experts and representatives of national competent authorities for blood from thirteen European Union and European Economic Area (EU/EEA) Member States (MS), Switzerland, the World Health Organization, the European Directorate for the Quality of Medicines and Health Care of the Council of Europe, the US Food and Drug Administration, and the ECDC. During the meeting, the current use of PRTs in the EU/EEA MS and Switzerland was verified, with particular reference to emerging infectious diseases (see Appendix). In this article, we also present expert discussions and a common view on the potential use of PRT as a part of both preparedness and response to threats posed to blood safety by outbreaks of infectious disease.

Clinical impact of amotosalen-ultraviolet A pathogen-inactivated platelets stored for up to 7 days

BACKGROUND

Universal pathogen inactivation of platelet concentrates (PCs) using amotosalen/ultraviolet A with 7-day storage was implemented in Switzerland in 2011. Routine-use data were analyzed at the University Hospital Basel, Switzerland.

STUDY DESIGN

A retrospective two-cohort study of patient and PC characteristics, component usage, patient outcomes, count increments (CIs), and adverse events were analyzed for two consecutive 5-year periods with either 0- to 5-day-old conventional PC (C-PC) (n = 14,181) or 0- to 7-day-old pathogen-inactivated PC (PI-PC) (n = 22,579).

RESULTS

In both periods, PCs were issued for transfusion on a "first in, first out" basis. With 7-day PI-PC, wastage was reduced from 8.7% to 1.5%; 16.6% of transfused PI-PCs were more than 5 days old. Transfusion of PI-PC more than 5 days old compared with 5 days old or less did not increase platelet and RBC use on the same or next day as an indirect measure of hemostasis and did not increase transfusion reactions. Mean corrected count increments (CCIs) for PI-PC stored for 5 days or less were 22.6% lower than for C-PC (p < 0.001), and declined with increasing storage duration for both, although the correlation was weak (r2 = 0.005-0.014). Mean number of PCs used per patient and duration of PC support were not different for hematology/oncology, allogeneic and autologous hematopoietic stem cell transplant (HSCT), and general medical/surgical patients, who used the majority (~92.0%) of PI-PCs. Five-year treatment-related mortality in allogeneic HSCT was unchanged in the PI-PC period.

CONCLUSIONS

PI-PCs with 7-day storage reduced wastage and did not increase PC or red blood cell utilization or adverse reactions compared with fresh PI-PC or a historical control group, demonstrating preserved efficacy and safety.

Blood utilisation and transfusion reactions in adult patients transfused with conventional or pathogen-reduced platelets

Pathogen-reduced (PR) platelets are routinely used in many countries. Some studies reported changes in platelet and red blood cell (RBC) transfusion requirements in patients who received PR platelets when compared to conventional (CONV) platelets. Over a 28-month period we retrospectively analysed platelet utilisation, RBC transfusion trends, and transfusion reaction rates data from all transfused adult patients transfused at the Yale-New Haven Hospital, New Haven, CT, USA. We determined the number of RBC and platelet components administered between 2 and 24, 48, 72 or 96 h. A total of 3767 patients received 21 907 platelet components (CONV = 8912; PR = 12 995); 1,087 patients received only CONV platelets (1578 components) and 1,466 patients received only PR platelets (2604 components). The number of subsequently transfused platelet components was slightly higher following PR platelet components (P < 0·05); however, fewer RBCs were transfused following PR platelet administration (P < 0·05). The mean time-to-next platelet component transfusion was slightly shorter following PR platelet transfusion (P = 0·002). The rate of non-septic transfusion reactions did not differ (all P > 0·05). Septic transfusion reactions (N = 5) were seen only after CONV platelet transfusions (P = 0·011). These results provide evidence for comparable clinical efficacy of PR and CONV platelets. PR platelets eliminated septic transfusion reactions without increased risk of other types of transfusions with only slight increase in platelet utilisation.

Phased implementation of pathogen-reduced platelets in a health system facilitates increased manufacturing at the blood center

BACKGROUND

Pathogen reduction treatment (PRT) reduces the risk of transfusion‐transmitted infections from established and emerging organisms. Manufacturing, however, is complex. In our university health system, we phased in pathogen‐reduced platelets (PR PLTs) by patient population. We then assessed the implementation strategy and investigated factors in the supply chain that prevented us from meeting the goal of providing greater than 90% PR PLTs within 6 months.

STUDY DESIGN AND METHODS

In Phase 1, PR PLTs were provided in the outpatient cancer center. Phase 2 added inpatients undergoing bone marrow transplantation, and Phase 3 included all patients. In Phase 4, the blood center implemented manufacturing optimization strategies. Product supply and usage during the first 23 months after implementation were evaluated. Investigation of the supply chain included analysis of (1) the number of in‐state hospitals receiving PR PLTs; (2) the fraction of products eligible for PRT before and after manufacturing improvements.

RESULTS

During Phases 1 and 2, PR products comprised 44% and 53% of PLTs transfused in the phased‐in areas. At 6 months, 41% of PLTs were PR, and at 23 months, 92%. The fraction of PR PLTs transfused in our system correlated logarithmically with the number of in‐state hospitals receiving them (R² = 0.71) and the number of PR PLTs sold to those hospitals (R² = 0.80).

CONCLUSION

Phased implementation is a practical and ethical way to introduce PR PLTs in a health system and facilitates scalability at the blood center. Widespread availability of PR products may require collective action and can be increased by optimization strategies during manufacturing.

http://onlinelibrary.wiley.com/doi/10.1111/trf.15500/full

The long and winding road to pathogen reduction of platelets, red blood cells and whole blood

Pathogen reduction technologies (PRTs) have been developed to further reduce the current very low risks of acquiring transfusion-transmitted infections and promptly respond to emerging infectious threats. An entire portfolio of PRTs suitable for all blood components is not available, but the field is steadily progressing. While PRTs for plasma have been used for many years, PRTs for platelets, red blood cells (RBC) and whole blood (WB) were developed more slowly, due to difficulties in preserving cell functions during storage. Two commercial platelet PRTs use ultra violet (UV) A and UVB light in the presence of amotosalen or riboflavin to inactivate pathogens' nucleic acids, while a third experimental PRT uses UVC light only. Two PRTs for WB and RBC have been tested in experimental clinical trials with storage limited to 21 or 35 days, due to unacceptably high RBC storage lesion beyond these time limits. This review summarizes pre-clinical investigations and selected outcomes from clinical trials using the above PRTs. Further studies are warranted to decrease cell storage lesions after PRT treatment and to test PRTs in different medical and surgical conditions. Affordability remains a major administrative obstacle to PRT use, particularly so in geographical regions with higher risks of transfusion-transmissible infections.

Microbiological Screening of Platelet Concentrates in Europe

The risk of transfusion-associated sepsis due to transmission of bacteria is a persistent problem in the transfusion field. Despite numerous interventions to reduce the risk, cases of bacterial sepsis following transfusion are repeatedly being reported. Especially platelet concentrates are highly susceptible to bacterial contaminations due to the growth-promoting storage conditions. In Europe, blood establishments and national authorities have implemented individual precaution measures to mitigate the risk of bacterial transmission. To obtain an overview of the different approaches, we compiled information from national authorities, blood establishments, and the current literature. Several aspects such as the shelf life of platelets, time of sampling and the applied control measures are compared between the member states. The analysis of the data revealed a broad heterogeneity of procedures on a national level ranging from platelet release without any safety testing up to mandatory screening of all platelet concentrates prior to transfusion. Despite the substantial progress made in recent years, several bacterial reports on transfusion-associated sepsis indicate that further efforts are needed to increase the safety of blood transfusions in the long term.

International haemovigilance: what have we learned and what do we need to do next?

The International Haemovigilance Network (IHN) defines haemovigilance as 'a set of surveillance procedures covering the whole transfusion chain (from the collection of blood and its components to the follow-up of recipients), intended to collect and assess information on unexpected or undesirable effects resulting from the therapeutic use of labile blood products, and to prevent their occurrence or recurrence'. IHN, the International Society of Blood Transfusion and World Health Organization work together to support both developing and established haemovigilance systems. Haemovigilance systems provide valuable data on a range of adverse events related to blood donation and clinical transfusion, from donor syncopal events to transfusion-transmitted infections, immunological complications and the impact of human errors. Harmonised definitions for most adverse reactions have been developed and validated internationally. Definitions of pulmonary complications are again under review. Haemovigilance data have resulted in changes in policy, products and practice, and can complement and inform clinical audit and research, leading to improved blood donor safety, optimised product use and better clinical outcomes after transfusion. However, more work is needed. Not all countries have haemovigilance systems in place. More robust data and careful analysis are required to improve the understanding of the causes, occurrence and clinical outcomes of these events. Wider dissemination of results will facilitate health policy development internationally, and implementation of haemovigilance recommendations will support further important progress in blood safety.