Plasma for direct therapeutic use, for today and tomorrow: A short critical overview

Plasma Isoagglutinin Depletion for Blood Group Independent Plasma Transfusion

Background

Plasma transfusion is one of the basic treatments in patients with major blood loss. The anti-A and anti-B antibodies contained in the plasma demand ABO blood group compatibility. This is limiting the use of plasma in emergency situations and can cause a shortage in the supply of plasma of certain blood groups. We developed a method for anti-A and anti-B depletion by adsorbing plasma isoagglutinins using red blood cells.

Materials and Methods

Three units of fresh frozen plasma were thawed after quarantine storage, pooled, and an aliquot of red cell concentrate was added. After 2 h of incubation at room temperature antibody-red-cell complexes were removed by centrifugation, the isoagglutinin-depleted plasma was split into three units and deep frozen. Isoagglutinin titers, free hemoglobin, residual red cells, clotting factor activity, and sterility of plasma units were determined after isoagglutinin depletion and a double freeze-thawing procedure.

Results

Anti-B titers in group A plasma were reduced from values of 1:64 to 1:1 or lower, anti-A titers in group B plasma decreased from values of 1:128 to at least 1:16. Postprocedure clotting factor activities were preserved with 88.0 ± 7.3% (factor V), 106.9 ± 11.4% (factor VIII), and 84.0 ± 7.5% (factor XI) fulfilling the quality control requirements. No residual red cells were found, but free hemoglobin slightly increased to 53.7 ± 5.2 μmol/L. All units were sterile.

Discussion

We described a method for the production of anti-A- and anti-B-depleted plasma in a closed system that uses standard equipment. The resulting isoagglutinin-depleted plasma may allow for blood group independent plasma transfusion.

Current Practice in FFP Preparation and Use in Greece: A National Survey

Objective

Fresh frozen plasma (FFP) transfusion is widely used in modern clinical settings. Practices regarding its use vary due to lack of guidelines from randomized trials. The aim of this study was to assess both the current practices regarding FFP production, use, and wastage and the implementation of quality control (QC), female donor plasma production policies, and use of pharmaceutical hemostatic agents in Greece.

Materials and Methods

The study was conducted during February-April 2018. For the first part of the study, data including FFP transfusion indication, hospital department, diagnosis, FFP units/transfusion episode, ABO compatibility, blood donor’s sex, and reasons for discarding were collected. For the second part, questionnaire data were analyzed.

Results

According to data from 20 Greek hospitals, 12655 FFP units were transfused to 2700 patients during 5069 transfusion episodes in the studied period of time. Most patients were hospitalized in internal medicine, general surgery, and intensive care unit departments. Each patient received on average 4.69 units (2.5 units/episode). Transfusion requests were in accordance with international guidelines in 63.44% of cases and 99.04% of the units were given to ABO-identical patients. Main reasons for discarding included failure to meet quality requirements (30.06%), female donors (22.17%), and other causes (27.26%). Among 96.9% of all transfusion services across the country, 28.26% perform QC according to the directions of the European Directorate for the Quality of Medicines & Health Care and 68.83% discard plasma from female donors. Pharmaceutic hemostatic agents are used in 37.23% of the hospitals.

Conclusion

This is the first national survey regarding FFP production and transfusion in Greece. Staff of internal medicine, general surgery, and ICU departments, where most FFP-transfused patients are hospitalized, should be regularly involved in training on contemporary transfusion guidelines. Upcoming centralization of FFP production and inventory management could help in homogenizing practices regarding FFP use and improve product quality. Strengthening the use of pharmaceutic hemostatic agents could improve patients’ management.

Amotosalen-inactivated fresh frozen plasma is comparable to solvent-detergent inactivated plasma to treat thrombotic thrombocytopenic purpura

BACKGROUND

Therapeutic Plasma Exchange (TPE) is the primary therapy of immune-mediated Thrombotic Thrombocytopenic Purpura (iTTP). Efficacy and safety data for TPE of iTTP have been assessed with Quarantine and Solvent-Detergent inactivated (SD) plasma. Here, amotosalen-UVA pathogen inactivated (AI) plasma, also in routine use, was evaluated in iTTP.

METHODS

We conducted a retrospective review of iTTP cases prospectively reported to the French national registry (2010-2013). Cases reviewed underwent TPE with ≥70% of either AI or SD plasma. The primary endpoint was time to platelet count recovery; secondary endpoints were related to follow-up (sustained remission, relapses, flare-ups and refractoriness).

RESULTS

30 Test patients were identified in the AI group which could be timely matched to 40 Control patients in the SD group. The groups were fairly comparable for clinical presentation. Major findings were: (i) iTTP patients were exposed to lower plasma volumes in the AI group than in the SD group; (ii) Recovery rates were comparable between the groups. Median time to platelet count recovery (>150 × 10⁹/L) trended to be shorter in the AI group though non significantly. Tolerance of AI vs SD plasma was of comparable frequency and severity in either group.

CONCLUSION

TPE with Amotosalen-inactivated plasma demonstrated therapeutic efficacy and tolerability for iTTP patients. In view of the retrospective design, confirmation of these results is required in larger prospective studies.

The plasma supply in France

Contrary to economically comparable countries, France has had a versatile policy to process and manufacture therapeutic plasma, and to apply safety measures. This has principally affected the origin of plasma (whole blood supernatant versus apheresis), and the application or not of a chemical process. At the time being, the civilian and Army Forces blood establishments produce more than 99% of the plasma issued for patients in need; safety means consist in a large part of quarantine and, to a lesser extent, to a pathogen reduction technology process (Amotosalen-HCl-UVA). The blood establishments ship plasma to the national manufacturer of blood derivatives. Plasma in France is strictly within the Voluntary Non-Remunerated pathway with no breach to this principle to be expected for both labile components and source plasma. The constant hemovigilance allows reflection to make policies evolving, with respect to safety measures particularly to reduce cases of allergy.