Quality of life and cost-effectiveness of convalescent plasma compared to standard care for hospitalized COVID-19 patients in the CONCOR-1 trial

BACKGROUND

The CONvalescent Plasma for Hospitalized Adults With COVID-19 Respiratory Illness (CONCOR-1) trial was a multicenter randomized controlled trial assessing convalescent plasma in hospitalized COVID-19 patients. This study evaluates the cost-effectiveness of convalescent plasma and its impact on quality-of-life to provide insight into its potential as an alternative treatment in resource-constrained settings.

METHODS

Individual patient data on health outcomes and resource utilization from the CONCOR-1 trial were used to conduct the analysis from the Canadian public payer's perspective with a time horizon of 30 days post-randomization. Baseline and 30-day EQ-5D-5L were measured to calculate quality-adjusted survival. All costs are presented in 2021 Canadian dollars. The base case assessed the EQ-5D-5L scores of hospitalized inpatients reporting at both timepoints, and a utility score of 0 was assigned for patients who died within 30 days. Costs for all patients enrolled were used. The sensitivity analysis utilizes EQ-5D-5L scores from the same population but only uses costs from this population.

RESULTS

940 patients were randomized: 627 received CCP and 313 received standard care. The total costs were $28,716 (standard deviation, $25,380) and $24,258 ($22,939) for the convalescent plasma and standard care arms respectively. EQ-5D-5L scores were 0.61 in both arms (p = .85) at baseline. At 30 days, EQ-5D-5L scores were 0.63 and 0.64 for patients in the convalescent plasma and standard care arms, respectively (p = .46). The incremental cost was $4458 and the incremental quality-adjusted life day was -0.078.

DISCUSSION

Convalescent plasma was less effective and more costly than standard care in treating hospitalized COVID-19.

Characterization of antibodies to SARS-CoV-2 in lyophilized plasma prepared with amotosalen-UVA pathogen reduction

BACKGROUND

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2)-infected patients exhibit disease ranging from asymptomatic to severe pneumonia, multi-organ failure, and death. convalescent COVID plasma (CCP) from recovered patients with high levels of neutralizing antibodies has demonstrated therapeutic efficacy to reduce the morbidity of coronavirus disease 2019 (COVID-19) in some studies. The development of assays to characterize the activity of CCP to neutralize SARS-CoV-2 infectivity offers the possibility to improve potential therapeutic efficacy. Lyophilization of CCP may increase the availability of this therapy. We hypothesized that SARS-CoV-2 antibody profiles of pooled lyophilized pathogen-reduced CCP from COVID-19-recovered blood donors retains virus-neutralizing efficacy as reported for frozen pathogen-reduced CCP.

METHODS

Pooled lyophilized pathogen-reduced plasma was prepared from recovered COVID plasma donors. Antibodies to SARS-CoV-2 were characterized in each donor plasma prior to pathogen reduction and lyophilization and after lyophilization of individual CCP, and in the lyophilized CCP pool. Several complimentary assays were used to characterize antibody levels, neutralizing capacity, and the spectrum of antigen reactivity. The mean values for individual plasma samples and the value in the pool were compared.

RESULTS

The mean ratio for antibody binding to SARS-CoV-2 antigens before and after treatment was 0.95 ± 0.22 mean fluorescent intensity (MFI) units. Antibody activity to an array of influenza virus antigens demonstrated a mean activity ratio of 0.92 ± 0.12 MFI before and after treatment.

CONCLUSIONS

The antibody activity in pooled pathogen-reduced lyophilized CCPs demonstrated minimal impact due to pathogen reduction treatment and lyophilization.

Overestimation of fibrinogen concentration in cryoprecipitate by repeated freeze-thawing with long thawing period as used in the Clauss method

BACKGROUND

Cryoprecipitate (CRY) is widely used for treating acquired hypofibrinogenemia. During our study to determine an optimal preparation method, we noticed that the measurement of fibrinogen concentration in CRY had a risk of overestimation. We analyzed this condition and mechanism.

STUDY DESIGN AND METHODS

CRY was prepared from fresh frozen plasma (FFP) under four conditions: A, 30 h thawing time, 2 cycles; B, 24 h thawing time, 2 cycles; C, 30 h thawing time, 1 cycle; and D, 24 h thawing time, 1 cycle. Then, fibrinogen concentrations in CRY and cryosupernatant (CS) were measured by the Clauss method.

RESULTS

Purification (CRY/CRY+CS) and recovery (CRY/FFP) rates in CRY prepared under 2-cycle conditions were higher than those under 1 cycle. However, recovery rates often exceeded 100%, particularly in the case of CRY prepared under A condition, and fibrinogen concentrations calculated by direct measurement were higher than those indirectly calculated from FFP and CS, suggesting an overestimation of fibrinogen values. The level of soluble fibrin monomer complex was considerably higher in CRY prepared under A than under D condition, indicating that CRY adopted a hypercoagulated state. We further found that repeated thawing/freezing increased fibrinogen values as measured by the Clauss method while mechanical vortexing did not.

DISCUSSION

Our findings suggest that direct assessment of fibrinogen contents in CRY prepared by repeated freeze-thawing with a longer thawing period presents a higher risk of overestimation. For the purpose of quality control, we propose an alternative method to indirectly estimate fibrinogen concentrations in CRY from those of CS and FFP.

Frozen and freeze-dried solvent/detergent treated plasma: Two different pharmaceutical formulations with comparable quality

BACKGROUND

OctaplasLG is a frozen solvent/detergent-treated plasma product used for treating complex coagulation factor deficiencies or as substitution therapy in emergency situations where specific factor concentrates are not available. A new freeze-dried (also known as lyophilized) form of OctaplasLG, referred as OctaplasLG Lyo (Octapharma AG, Switzerland) offers rapid reconstitution and more flexible storage conditions, improving logistics and utilization. This study compared the biochemical quality of OctaplasLG Lyo with OctaplasLG and single-donor fresh frozen plasma units.

STUDY DESIGN AND METHODS

Three batches of OctaplasLG Lyo, manufactured for production process qualification, and 12 batches of OctaplasLG were provided by Octapharma AB (Sweden). Twelve units of fresh frozen plasma were collected by the local FDA-licensed blood provider. All plasma samples were assessed for global coagulation parameters, coagulation factors and protease inhibitors, activation markers of coagulation and fibrinolysis, and important plasma proteins. Quality control assays were conducted in accordance with European Pharmacopeia requirements.

RESULTS

Frozen and freeze-dried OctaplasLG demonstrated comparable quality profiles upon thawing or reconstitution. All coagulation factor and protease inhibitor activity parameters were in line with levels mandated by the European Pharmacopeia. Fresh frozen plasma units showed comparable coagulation factor activities, with higher protein S and plasmin inhibitor levels than the OctaplasLG products. Fresh frozen plasma parameters showed high lot-to-lot variations.

DISCUSSION

The two pharmaceutical forms of OctaplasLG (frozen and freeze-dried) have comparable biochemical quality. Key features of OctaplasLG Lyo are rapid reconstitution time and storage flexibility, which may improve logistics and utilization, and have particular advantages in emergency situations and pre-hospital settings.

Cryoprecipitate transfusion in bleeding patients

OBJECTIVES

The management of acquired coagulopathy in multiple clinical settings frequently involves fibrinogen supplementation. Cryoprecipitate, a multidonor product, is widely used for the treatment of acquired hypofibrinogenemia following massive bleeding, but it has been associated with adverse events. We aimed to review the latest evidence on cryoprecipitate for treatment of bleeding.

METHODS

We conducted a narrative review of current literature on cryoprecipitate therapy, describing its history, formulations and preparation, and recommended dosing. We also reviewed guideline recommendations on the use of cryoprecipitate in bleeding situations and recent studies on its efficacy and safety.

RESULTS

Cryoprecipitate has a relatively high fibrinogen content; however, as it is produced by pooling fresh frozen donor plasma, the fibrinogen content per unit can vary considerably. Current guidelines suggest that cryoprecipitate use should be limited to treating hypofibrinogenemia in patients with clinical bleeding. Until recently, cryoprecipitate was deemed unsuitable for pathogen reduction, and potential safety concerns and lack of standardized fibrinogen content have led to some professional bodies recommending that cryoprecipitate is only indicated for the treatment of bleeding and hypofibrinogenemia in perioperative settings where fibrinogen concentrate is not available. While cryoprecipitate is effective in increasing plasma fibrinogen levels, data on its clinical efficacy are limited.

CONCLUSIONS

There is a lack of robust evidence to support the use of cryoprecipitate in bleeding patients, with few prospective, randomized clinical trials performed to date. Clinical trials in bleeding settings are needed to investigate the safety and efficacy of cryoprecipitate and to determine its optimal use and administration.

Estimation of the latent therapeutic demand for immunoglobulin therapies in autoimmune neuropathies in the United States

BACKGROUND AND OBJECTIVES

The use of immunoglobulin (IG) solutions as an immunomodulatory therapy in certain neurological conditions has become an established modality and represents a significant proportion of total IG use. The estimation of the evidence-based potential demand designated as the latent therapeutic demand (LTD) for IG in these diseases is required for adequate planning of the plasma supply required to manufacture the product.

MATERIALS AND METHODS

The diseases studied included chronic inflammatory demyelinating polyneuropathy (CIDP), Guillain-Barré syndrome (GBS) and multifocal motor neuropathy (MMN). The LTD for IG was assessed using a decision analysis model, using Microsoft Excel. The model analysed the epidemiological and clinical factors contributing to IG usage. One-way sensitivity analysis and probabilistic sensitivity analysis derived the LTD in grams per 1000 inhabitants. The key variables included the treatment schedule and the prevalence of the disease.

RESULTS

The model estimates that an average annual IG demand and standard deviation for CIDP, GBS and MMN in the United States is 83.05 ± 24.5, 6.1 ± 3.2 and 36.1 ± 25.5 g/1000 inhabitants, respectively.

CONCLUSION

Together with previous work on the LTD for IG in immunodeficiencies, these results indicate that current IG usage reflects the estimated LTD for the main indications for IG in the United States The wide range of LTD found in all these studies emphasizes the need for more precise assessment of the underlying variables, particularly disease prevalence and dosage. Further studies on other indications such as secondary immunodeficiencies will augment these results and will assist in guiding demand planning for IG use and plasma collection in the United States and inform blood policy in other countries.

A trend of dropping anti-SARS-CoV-2 plaque reduction neutralization test titers over time in Canadian convalescent plasma donors

BACKGROUND

Convalescent plasma products are a potential passive immunotherapy for Coronavirus disease 2019 (COVID-19) disease. Various approaches have been utilized to determine the concentration of Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2)-neutralizing antibodies in plasma products. The Canadian Blood Services used Plaque Reduction Neutralization Test 50 (PRNT₅₀₎ -generated values to qualify convalescent plasma donations supporting clinical trials in Canada. This manuscript describes changes in PRNT₅₀ titers of repeat male plasma donations collected approximately 1-4 months after onset of COVID-19 signs and symptoms in donors.

STUDY DESIGN AND METHODS

Men were eligible to donate if they: met standard criteria, were < 67 years of age, reported a previous SARS-CoV-2-positive nucleic acid test, and recovered and were symptom free for at least 28 days prior to donation. Repeat donation analysis required at least one original and one repeat donation where a PRNT₅₀ was performed.

RESULTS

From April 29, 2020 to July 25, 2020, 156 donors donated once, with 78 (50%) of the donated plasma having PRNT₅₀ titers of ≥1:160. Thirty-seven (23.7%) of the donated plasma had a titer of 1:40 or 1:80 (individuals donating this plasma were asked to donate a second time only). A total of 30 donors (19.2%) had repeat donations. Of the repeat donors, 15 (50%) had at least an eightfold change from peak to trough PRNT₅₀ titers within greater than 90 days after onset of COVID-19 symptoms.

CONCLUSIONS

Blood operators cannot infer that SARS-CoV-2 PRNT₅₀ will remain high in repeat plasma donors 3-4 months after onset of COVID-19 symptoms.

Enabling accurate measurement of activated factor XI (FXIa) in therapeutic immunoglobulin products

Background and objectives

In 2010, an intravenous immunoglobulin (IVIG) product was removed from the market due to an association with serious thromboembolic events. Investigations revealed that factor XIa (FXIa) was present as a process‐related impurity. This study investigated the ability of two commercial FXIa assays to measure FXIa in immunoglobulin preparations and conducted a survey of FXIa activity in marketed immunoglobulin products.

Materials and methods

Factor XIa assays were modified to include spiking of samples with FXIa before testing. An immunoglobulin product and its excipient were used to assess the ability of the assays to recover the spiked FXIa levels.

Results

The Biophen FXIa assay required a high pre‐dilution of the sample to obtain statistically valid results and complete FXIa recovery. The ROX FXIa assay was more sensitive, giving statistically valid results at a lower sample pre‐dilution and FXIa spike level. This modified ROX FXIa assay was used to assay 17 lots of immunoglobulin products for FXIa. Two product lots had measurable FXIa levels without the need for spiking. A further 3 lots produced detectable but not statistically valid FXIa results when left unspiked. Spiking produced statistically valid assays and recoveries above 100%, demonstrating inherent FXIa.

Conclusion

This study shows marketed immunoglobulin products can contain detectable levels of FXIa. Spiking brings the FXIa levels into the quantifiable range of the assay, allowing measurement of inherent FXIa. Accurate measurement is important to inform on ‘safe’ levels of FXIa in these products and allow future safety guidelines to be set.

Nanofiltration as a robust method contributing to viral safety of plasma-derived therapeutics: 20 years' experience of the plasma protein manufacturers

Background

Nanofiltration entails the filtering of protein solutions through membranes with pores of nanometric sizes that have the capability to effectively retain a wide range of viruses.

Study Design and Methods

Data were collected from 754 virus validation studies (individual data points) by Plasma Protein Therapeutics Association member companies and analyzed for the capacity of a range of nanofilters to remove viruses with different physicochemical properties and sizes. Different plasma product intermediates were spiked with viruses and filtered through nanofilters with different pore sizes using either tangential or dead‐end mode under constant pressure or constant flow. Filtration was performed according to validated scaled‐down laboratory conditions reflecting manufacturing processes. Effectiveness of viral removal was assessed using cell culture infectivity assays or polymerase chain reaction (PCR).

Results

The nanofiltration process demonstrated a high efficacy and robustness for virus removal. The main factors affecting nanofiltration efficacy are nanofilter pore size and virus size. The capacity of nanofilters to remove smaller, nonenveloped viruses was dependent on filter pore size and whether the nanofiltration process was integrated and designed with the intention to provide effective parvovirus retention. Volume filtered, operating pressure, and total protein concentration did not have a significant impact on the effectiveness of virus removal capacity within the investigated ranges.

Conclusions

The largest and most diverse nanofiltration data collection to date substantiates the effectiveness and robustness of nanofiltration in virus removal under manufacturing conditions of different plasma‐derived proteins. Nanofiltration can enhance product safety by providing very high removal capacity of viruses including small non‐enveloped viruses.

Audit of provincial IVIG Request Forms and efficacy documentation in four Ontario tertiary care centres

OBJECTIVE

Retrospective audit of IVIG Request Forms in four Ontario tertiary care centres: to determine the case mix of new IVIG requests, to authenticate information provided, and to determine documentation of clinical efficacy.

AIMS

To understand contributors to increases in IVIG utilisation and to determine whether IVIG is being used and monitored appropriately.

INTRODUCTION

Intravenous immunoglobulin (IVIG) use in Canada is high compared with other developed countries. We performed a retrospective audit of new IVIG Request Forms across four tertiary care centres in Ontario, one with an active surveillance programme, to determine the case mix, authenticate information provided and assess documentation of efficacy.

METHODS

Consecutive adult patients with a first-time IVIG request in 2014 were included. The ordering physician specialty, form completeness, documentation of diagnostic criteria for the medical condition and indication for IVIG use and documentation of efficacy were assessed by form and chart review.

RESULTS

Of 178 patients, the most common indications for IVIG were immune thrombocytopenia (24.2%) and secondary immune deficiency (20.2%). The most frequent prescribers were haematologists (37.6%) and neurologists (10.7%). Other conditions not listed on the form represented 24.2% of cases, with most not indicated in current guidelines. A total of 32.6% of cases overall lacked verification of diagnostic criteria and 51.7% lacked verification for IVIG utilisation criteria, with the number of cases meeting criteria based on documentation being higher at the active surveillance site (P = 0.005). A total of 19.1% of cases had a discrepancy between the indication written on the form and the documented clinical diagnosis. A total of 18.7% of clinic notes following IVIG had no mention of efficacy.

CONCLUSION

Our audit demonstrates a lack of compliance with IVIG Request Form requirements, a lack of documentation of diagnostic criteria and efficacy, and suggests inappropriate use of IVIG. Current implementation of the form may not be sufficient as a strategy for improving appropriate IVIG use.

[Genetic diversity of human erythroviruses: consequences on infectious safety of blood products and plasma derivatives]

Sequence analysis of human erythroviruses shows an organization into three genotypes; genotype 1 with B19 Parvovirus (B19 V) and 2 new genotypes with a genetic diversity markedly distinct from that of B19 V. The frequency of each genotype depends on geographic origin and population. Human erythroviruses infection can be transmitted by transfusion. In immunocompetent recipients, B19 V exposure is generally inconsequential, since a large proportion is immunized. However, such a contamination may have severe clinical outcome in not immunized patients with shortened red cell survival, in seronegative pregnant women and in immunocompromised patients. No prevention of blood transmission is currently performed, but a preventive strategy could be discussed for at-risk recipients. In plasma derivatives, B19VDNA screening is done with a threshold of 104 IU/mL. With recent data of a new classification on the human erythroviruses genotypes, DNA testing assays would be validated in accordance with genetic variability, in order to guarantee optimal safety.