Improving the safety of whole blood-derived transfusion products with a riboflavin-based pathogen reduction technology

Expanding the platelet inventory to mitigate the impact of severe shortages

The platelet collection and distribution system, based on volunteer nonremunerated donors, apheresis platelet collections, and primarily 1-directional distribution of platelets for up to 5-day room temperature storage at hospitals, typically performs well and provides therapeutic support for hundreds of thousands of patients annually. However, direct and indirect effects of the coronavirus disease 2019 pandemic, particularly during the Omicron wave, produced dramatic systemic failures and severe shortages. We propose 4 initiatives to reinforce the existing platelet pipeline and buffer the platelet supply against future unexpected disruptions.

The Mirasol Evaluation of Reduction in Infections Trial (MERIT): study protocol for a randomized controlled clinical trial

BACKGROUND

Transfusion-transmitted infections (TTIs) are a global health challenge. One new approach to reduce TTIs is the use of pathogen reduction technology (PRT). In vitro, Mirasol PRT reduces the infectious load in whole blood (WB) by at least 99%. However, there are limited in vivo data on the safety and efficacy of Mirasol PRT. The objective of the Mirasol Evaluation of Reduction in Infections Trial (MERIT) is to investigate whether Mirasol PRT of WB can prevent seven targeted TTIs (malaria, bacteria, human immunodeficiency virus, hepatitis B virus, hepatitis C virus, hepatitis E virus, and human herpesvirus 8).

METHODS

MERIT is a randomized, double-blinded, controlled clinical trial. Recruitment started in November 2019 and is expected to end in 2024. Consenting participants who require transfusion as medically indicated at three hospitals in Kampala, Uganda, will be randomized to receive either Mirasol-treated WB (n = 1000) or standard WB (n = 1000). TTI testing will be performed on donor units and recipients (pre-transfusion and day 2, day 7, week 4, and week 10 after transfusion). The primary endpoint is the cumulative incidence of one or more targeted TTIs from the Mirasol-treated WB vs. standard WB in a previously negative recipient for the specific TTI that is also detected in the donor unit. Log-binomial regression models will be used to estimate the relative risk reduction of a TTI by 10 weeks associated with Mirasol PRT. The clinical effectiveness of Mirasol WB compared to standard WB products in recipients will also be evaluated.

DISCUSSION

Screening infrastructure for TTIs in low-resource settings has gaps, even for major TTIs. PRT presents a fast, potentially cost-effective, and easy-to-use technology to improve blood safety. MERIT is the largest clinical trial designed to evaluate the use of Mirasol PRT for WB. In addition, this trial will provide data on TTIs in Uganda.

TRIAL REGISTRATION

Mirasol Evaluation of Reduction in Infections Trial (MERIT) NCT03737669 . Registered on 9 November 2018.

Improvement of Blood Processing and Safety by Automation and Pathogen Reduction Technology

Introduction

The objective of the present study was to describe the experience of the Blood and Tissues Bank of Aragon with the Reveos® Automated Blood Processing System and Mirasol® Pathogen Reduction Technology (PRT) System, comparing retrospectively routine quality data obtained in two different observation periods.

Methods

Comparing quality data encompassing 6,525 blood components from the period 2007-2012, when the semi-automated buffy coat method was used in routine, with 6,553 quality data from the period 2014-2019, when the Reveos system and subsequently the Mirasol system were implemented in routine.

Results

Moving from buffy coat to Reveos led to decreased discard rates of whole blood units (1.2 to 0.1%), increased hemoglobin content (48.1 ± 7.6 to 55.4 ± 6.6 g/unit), and hematocrit (58.9 ± 6.5% to 60.0 ± 4.9%) in red blood cell concentrates. Platelet concentrates (PCs) in both periods had similar yields (3.5 ×10¹¹). Whereas in the earlier period, PCs resulted from pooling 5 buffy coats, in the second period 25% of PCs were prepared from 4 interim platelet units. The mean level of factor VIII in plasma was significantly higher with Reveos (92.8 vs. 97.3 IU). Mirasol PRT treatment of PCs reduced expiry rates to 1.2% in 2019. One septic transmission was reported with a non-PRT treated PCs, but none with PRT-treated PCs.

Conclusion

Automation contributed to standardization, efficiency, and improvement of blood processing. Released resources enabled the effortless implementation of PRT. The combination of both technologies guaranteed the self-sufficiency and improvement of blood safety.

Retrospective Study of the Seroprevalence of HIV, HCV, and HBV in Blood Donors at a Blood Bank of Western Mexico

Obtaining blood which is safe for transfusions is one of the principal challenges in the health systems of developing countries. Supply of contaminated blood increases morbidity, mortality, and the costs of patient care. In Mexico, serological screening is mandatory, but only a few of the main blood banks routinely perform a nucleic acid test (NAT). Data from 80,391 blood donations processed between August 2018 and December 2019 at the Central Blood Bank of the Western National Medical Center of the Mexican Social Security Institute (IMSS) were analyzed. All donors were screened for serological markers and NAT was performed. Reactive donors were followed-up to confirm their results. The number of reactive donors and seroprevalence rates for HIV, HCV, and HBV were 152 (18.91/10,000), 385 (47.89/10,000), and 181 (22.51/10,000), respectively; however, these rates decreased when NAT-confirmed reactive results were considered. Male donors were found to have a higher seroprevalence than females, and younger donors higher than older donors. The present study shows that HIV, HCV, and HBV seroprevalence in blood donors in Western Mexico is low. We propose that Mexico should establish future strategies, including pathogen reduction technologies (PRTs), in order to improve blood safety and reduce transfusion-transmissible infections (TTIs).

Clinical Laboratory Biosafety Gaps: Lessons Learned from Past Outbreaks Reveal a Path to a Safer Future

Patient care and public health require timely, reliable laboratory testing. However, clinical laboratory professionals rarely know whether patient specimens contain infectious agents, making ensuring biosafety while performing testing procedures challenging. The importance of biosafety in clinical laboratories was highlighted during the 2014 Ebola outbreak, where concerns about biosafety resulted in delayed diagnoses and contributed to patient deaths. This review is a collaboration between subject matter experts from large and small laboratories and the federal government to evaluate the capability of clinical laboratories to manage biosafety risks and safely test patient specimens. We discuss the complexity of clinical laboratories, including anatomic pathology, and describe how applying current biosafety guidance may be difficult as these guidelines, largely based on practices in research laboratories, do not always correspond to the unique clinical laboratory environments and their specialized equipment and processes. We retrospectively describe the biosafety gaps and opportunities for improvement in the areas of risk assessment and management; automated and manual laboratory disciplines; specimen collection, processing, and storage; test utilization; equipment and instrumentation safety; disinfection practices; personal protective equipment; waste management; laboratory personnel training and competency assessment; accreditation processes; and ethical guidance. Also addressed are the unique biosafety challenges successfully handled by a Texas community hospital clinical laboratory that performed testing for patients with Ebola without a formal biocontainment unit. The gaps in knowledge and practices identified in previous and ongoing outbreaks demonstrate the need for collaborative, comprehensive solutions to improve clinical laboratory biosafety and to better combat future emerging infectious disease outbreaks.

A Whole Virion Vaccine for COVID-19 Produced via a Novel Inactivation Method and Preliminary Demonstration of Efficacy in an Animal Challenge Model

The COVID-19 pandemic has generated intense interest in the rapid development and evaluation of vaccine candidates for this disease and other emerging diseases. Several novel methods for preparing vaccine candidates are currently undergoing clinical evaluation in response to the urgent need to prevent the spread of COVID-19. In many cases, these methods rely on new approaches for vaccine production and immune stimulation. We report on the use of a novel method (SolaVAX) for production of an inactivated vaccine candidate and the testing of that candidate in a hamster animal model for its ability to prevent infection upon challenge with SARS-CoV-2 virus. The studies employed in this work included an evaluation of the levels of neutralizing antibody produced post-vaccination, levels of specific antibody sub-types to RBD and spike protein that were generated, evaluation of viral shedding post-challenge, flow cytometric and single cell sequencing data on cellular fractions and histopathological evaluation of tissues post-challenge. The results from this preliminary evaluation provide insight into the immunological responses occurring as a result of vaccination with the proposed vaccine candidate and the impact that adjuvant formulations, specifically developed to promote Th1 type immune responses, have on vaccine efficacy and protection against infection following challenge with live SARS-CoV-2. This data may have utility in the development of effective vaccine candidates broadly. Furthermore, the results of this preliminary evaluation suggest that preparation of a whole virion vaccine for COVID-19 using this specific photochemical method may have potential utility in the preparation of one such vaccine candidate.

Screening of at-risk blood donors for Chagas disease in non-endemic countries: Lessons from a 2-year experience in Tuscany, Italy

Background

Chagas disease (CD) is caused by the protozoan parasite Trypanosoma cruzi and is transmitted by blood‐sucking triatomine insects in endemic areas of Latin America. Transmission can also occur via blood transfusion and is a major cause of CD in non‐endemic areas.

Objectives

The aim of the study was to assess the prevalence of anti‐T. cruzi antibodies in blood donors at risk of infection in Tuscany, Italy, following the introduction of blood safety Italian legislation.

Material and methods

Donors (N = 1985) were tested in 2016 to 2018 for anti‐T. cruzi IgG using an immunochromatographic test (ICT). Chemiluminescent immunoassay (CLIA) was performed on ICT‐positive donors to exclude CD, whereas enzyme‐linked immunosorbent assay and western blot were performed in case of discordant results. All assays were performed on CD patients (N = 10) for validation.

Results

Ten blood donors had a positive ICT result, with a resulting T. cruzi seroprevalence of 0.5% but demonstrated negative results to CLIA, as well as to the other serological assays. The comparison of serological assays suggested a lower relative sensitivity of ICT.

Conclusion

The results of this study confirm the significance of serological testing in the screening strategy for CD. However, they provide evidence for discontinuing the use of ICT as a screening test and suggest that a sensitive, specific and multi‐sample format assay should be used at the national level for uniformity of results.

A novel cancer immunotherapy utilizing autologous tumour tissue

BACKGROUND

With the recent interest in personalized medicine for cancer patients and immune therapy, the field of cancer vaccines has been resurrected. Previous autologous, whole cell tumour vaccine trials have not produced convincing results due, in part to poor patient selection and inactivation methos that are harsh on the cells. These methods can alter protein structure and antigenic profiles making vaccine candidates ineffective in stimulating immune response to autochthonous tumour cells.

MATERIALS AND METHODS

We investigated a novel method for inactivating tumour cells that uses UVA/UVB light and riboflavin (vitamin B2) (RF + UV). RF + UV inactivates the tumour cells' ability to replicate, yet preserves tumour cell integrity and antigenicity.

RESULTS

Our results demonstrate that proteins are preserved on the surface of RF + UV-inactivated tumour cells and that they are immunogenic via induction of dendritic cell maturation, increase in IFNγ production and generation of tumour cell-specific IgG. Moreover, when formulated with an adjuvant ('Innocell vaccine') and tested in different murine tumour primary and metastatic disease models, decreased tumour growth, decreased metastatic disease and prolonged survival were observed. In addition, immune cells obtained from tumour tissue following vaccination had decreased exhausted and regulatory T cells, suggesting that activation of intra-tumoural T cells may be playing a role leading to reduced tumour growth.

CONCLUSIONS

These data suggest that the RF + UV inactivation of tumour cells may provide an efficacious method for generating autologous whole tumour cell vaccines for use in cancer patients.

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.

Factors affecting the quality, safety and marketing approval of clotting factor concentrates for haemophilia

Selecting therapeutic products for the treatment of haemophilia follows the process of obtaining market approval of products submitted to the scrutiny of a regulatory agency. In well-resourced countries, key decisions on whether a product is sufficiently safe and of high quality are made by highly expert and well-resourced agencies, such as the US Food and Drug Administration (FDA) and the European Medicines Agency (EMA). In countries lacking such agencies, well-informed decisions can still be made through an appreciation of the key issues affecting the quality, safety and efficacy of haemophilia products. A number of well-established principles may then be applied in order to make a choice. In this review, reflecting principles outlined by the World Federation of Hemophilia, we outline the key features in determining the acceptability of therapeutic products for haemophilia in order to ensure an optimal choice in all the environments providing haemophilia care.

Budget impact of implementing platelet pathogen reduction into the Italian blood transfusion system

BACKGROUND

Despite improvements in blood donor selection and screening procedures, transfusion recipients can still develop complications related to infections by known and emerging pathogens. Pathogen reduction technologies (PRT) have been developed to reduce such risks. The present study, developed whithin a wider health technology assessment (HTA) process, was undertaken to estimate the costs of the continuing increase in the use of platelet PRT in Italy.

MATERIALS AND METHODS

A multidisciplinary team was established to perform the HTA and conduct a budget impact analysis. Quantitative data on platelet use were derived from the 2015 national blood transfusion report and from the Italian Platelets Transfusion Assessment Study (IPTAS). The current national fee of 60 Euro per platelet PRT procedure was used to quantify the costs to the Italian National Health Service (INHS). The analysis adopts a 3-year time-frame. In order to identify the impact on budget we compared a scenario representing an increased use of PRT platelets over time with a control scenario in which standard platelets are used.

RESULTS

Progressive implementation of PRT for 20%, 40% and 66% of annual adult platelet doses could generate an increase in annual costs for the INHS amounting to approximately 7, 14 and 23 million Euros, respectively. Use of kits and devices suitable for the treatment of multiple adult platelet doses in one PRT procedure could lower costs.

DISCUSSION

In order to fully evaluate the societal perspective of implementing platelet PRT, the increase in costs must be balanced against the expected benefits (prevention of transfusion-transmissible infections, white cell inactivation, extension of platelet storage, discontinuation of pathogen detection testing). Further studies based on actual numbers of platelet transfusion complications and their societal cost at a local level are needed to see the full cost to benefit ratio of platelet PRT implementation in Italy, and to promote equal treatment for all citizens.