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BACKGROUND AND OBJECTIVES: Haemovigilance (HV) systems aim to improve transfusion outcomes in patients and donor safety. An important question for blood regulators is how to ensure an effective HV system. MATERIALS AND METHODS: We retrospectively analysed the HV reports submitted to Paul-Ehrlich-Institut over the last two decades. RESULTS: Between 2011 and 2020, 50.86 million units of blood components were used, and 8931 suspected serious donor and recipient adverse reactions (SARs), 874 serious adverse events (SAEs) and 12,073 donor look-backs were reported. Following implementation of specific risk-minimization measures (RMMs) between 2000 and 2010, SAR reporting rates decreased for transfusion-transmitted viral infections (TTVIs), transfusion-related acute lung injury (TRALI) and transfusion-transmitted bacterial infections (TTBIs), while increasing for other serious adverse transfusion reactions. Within this decade, the overall blood component use decreased. CONCLUSION: Long-term data collection forms the basis to establish trends and changes in reporting and to evaluate the effect of RMM. Standardized criteria for reaction types, seriousness and imputability assessments and availability of a denominator are important elements. Central data collection and independent assessment allow for monitoring HV data in a nationwide context over time. Stakeholder involvement and transparent feedback on the benefit of RMM will help to achieve the objectives of HV.

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Introduction: Regulatory activities aim to facilitate the safe use of novel therapeutics such as genetically engineered chimeric antigen receptor (CAR)-T cells. Toxicities associated with CAR-T-cell therapies have led to modified safety management guidance in clinical trials and the implementation of post-marketing requirements. The aim of this study was to estimate the effect of individual risk-minimizing measures to evaluate the appropriateness of regulatory activities. Methods: We re-examined clinical trial data prior to and after the introduction of revised treatment guidelines; we analysed spontaneous adverse drug reaction (ADR) reports submitted to the EudraVigilance database in 2019/2020 regarding their completeness; and we performed a survey of treatment centres in Germany that have been qualified for the use of commercial CAR-T cells. Results: Lower combined incidences of severe cytokine release syndrome (CRS) as well as neurotoxicity occurred following CAR-T-cell treatment after a revision of management guidelines, suggesting earlier intervention compared to before (12.6% vs. 20.5%). Numerous post-marketing ADR reports lacked information important for case assessment. Full details on treatment indication, CRS onset, outcome, and grading were available for just 38.3% of CRS cases. Survey responses support the majority of regulatory requirements for centre qualification. Time investment was highest for training of healthcare professionals, which required an average of 6.5 staff members (range 2-20) and lasted more than 2 days per person in half of the facilities. The need to harmonize the regulatory requirements for the different CAR-T-cell therapeutics was emphasized. Conclusion: Defined regulatory measures can support the safe and effective use of new therapies and are indicated for structured recording of post-marketing data, and the evaluation of such measures appears to be necessary for the continuous improvement.

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Background and Objectives: A sufficient supply of safe, high-quality blood components for transfusion is essential to the healthcare system in Germany. The requirements for the current reporting system are laid down in the German Transfusion Act. The present work elaborates on the advantages and limitations of the current reporting system and investigates the feasibility of a pilot project that collects specific data on blood supply based on weekly reports. Materials and Methods: Selected data on blood collection and supply from 2009 to 2021 derived from the §21 German Transfusion Act database were examined. In addition, a pilot study over a period of 12 months was conducted on a voluntary basis. The number of red blood cell (RBC) concentrates was documented and stock availability was calculated weekly. Results: From 2009 to 2021, the annual number of RBC concentrates decreased from 4.68 to 3.43 million, the per capita distribution decreased from 58 to 41 RBC concentrates per 1,000 inhabitants. These figures did not change significantly during the COVID-19 pandemic. The data of the 1-year pilot project represented 77% of the released RBC concentrates in Germany. Percentage share of O RhD positive RBC concentrates fluctuated between 35% and 22% and for O RhD negative concentrates between 17% and 5%. The availability of O RhD positive RBC concentrate stocks varied between 2.1 and 7.6 days. Conclusion: The data presented shows a decrease in annual RBC concentrate sales over an 11-year period and no further change over the past 2 years. A weekly monitoring of blood components detects acute problems in RBC provision and supply. Close monitoring seems helpful but should be combined with a nationwide supply strategy.

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Introduction: Following the first assessment of the effects of safety measures taken against transfusion-transmitted bacterial infections (TTBI), the Paul-Ehrlich-Institut (PEI) decided to newly analyze risk minimization measures (RMM) using German hemovigilance data from 2011 to 2020, focusing on blood components, recipients, and bacterial strains. Materials and Methods: The PEI assessed the imputability of all reported serious adverse reactions (SAR) relying mainly on microbiological test results. Reporting rates (RR) of suspected, confirmed, and fatal confirmed TTBI were calculated and compared to the previous reporting 10-year period (2001-2010) using Poisson regression to estimate RR ratios (RRR). Furthermore, details on blood component age, patients' medical history, and bacterial pathogenicity were collected. Results: With respect to the previous 10-year period, the number of suspected TTBI increased (n = 403), while fewer cases were confirmed (n = 40); the number of deaths remained more or less unchanged (n = 8). The RR for suspected TTBI were 7.9, 18.7, and 1.6 cases per million units transfused for red blood cells (RBC), platelet concentrates (PC), and fresh frozen plasma (FFP), respectively. RRR showed a statistically significant 2.5-fold increase in the RR for suspected TTBI after RBC administration from 2001-2010 to the period under review (p < 0.0001). The RR for confirmed TTBI were 0.4, 5.0, and 0.0 cases per million units transfused for RBC, PC, and FFP, respectively. Compared to the period 2001-2010, there was a statistically significant decrease in the RR of confirmed TTBI by half for PC (p = 0.0052). The RR for confirmed PC-caused TTBI with fatal outcome was 1.4 cases per million units transfused. Regardless of type of blood product transfused and outcome of SAR, the majority of TTBI occurred after administration of a product at the end of shelf life (40.0%) and to recipients of advanced age (median age: 68.5 years) and/or with severe immunosuppression (72.5%) due to decreased myelopoiesis (62.5%). 72.5% of the involved bacteria had a middle/high human pathogenicity. Conclusion: Despite a significant decrease in confirmed TTBI following PC transfusion in Germany after implementation of RMM, the current manufacture of blood products can still not prevent TTBI with fatal outcomes. As demonstrated in various countries, RMM like bacterial screening or pathogen reduction may measurably improve the safety of blood transfusion.

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Background and Objectives: In 1993, a quarantine storage of 6 months was introduced for plasma for transfusion and was reduced to 4 months in 2003, owing to the improvements of screening assays used in German blood establishments. The presented survey analyses the value of quarantine storage under the current screening conditions. Materials and Methods: From 2015 to 2019, we collected data on the total amount of released quarantine plasma as well as on the number of quarantine plasma not released due to a reactive screening test of a follow-up donation. Results: Responding establishments covered 84% of plasma units released within the sampled period. In 3,583,913 (99.98%) of the total 3,584,664 test pairs, all screening assays revealed a negative result, leading to plasma release from quarantine storage. In 442 out of the residual 751 cases, confirmed positive results for human immunodeficiency virus (24), hepatitis C virus (22), or hepatitis B virus (396) were obtained in the follow-up donations. Of them, 372 revealed negative ID-NAT results in their retain samples confirmed by using highly sensitive individual donor nucleic acid amplification technology. In 70 cases, no testing of retain samples was performed as plasma was released for fractionation. The maximum theoretical risk for an undetected human immunodeficiency virus, hepatitis C or B virus infection was less than 0.0001%. Conclusion: No positive donation were found under the current screening regime and the quarantine storage during the 5-year survey period. In view of the current type and sensitivity of screening tests in German blood establishments, the results allow a reassessment of the value of quarantine storage of plasma regarding duration and release modalities. Due to the more sensitive donor screening, shorter quarantine periods as well as dispensing quarantine storage can be discussed. A reduction in the safety standard of plasma transfusions need not be feared, and the availability of plasma for transfusions could be facilitated.

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We present the long-term outcomes of 44 patients who developed cerebral venous sinus thrombosis after vaccination with the adenoviral vector ChAdOx1 nCoV-19 COVID-19 vaccine. Assessment of the Extended Glasgow Outcome Scale was performed within 3-6 months after the initial hospital admissions. Patient outcomes ranged from good recovery (13 patients, 29.6%) to moderate disability (11 patients, 25.0%) and severe disability or vegetative state (6 patients, 13.6%). Fatal outcomes were reported in 14 patients (31.8%).

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BACKGROUND: Vaccine-induced immune thrombotic thrombocytopenia (VITT) is a severe adverse event of SARS-CoV-2 vaccination. We describe the characteristics of patients reported in Germany based on the Brighton Collaboration (BC) case definition criteria for Thrombosis and Thrombocytopenia Syndrome (TTS) and focus on patients with complete anti-platelet factor 4 (PF4)-antibody laboratory work up. METHODS: The adverse drug reaction database of the Paul-Ehrlich Institute was queried for TTS cases following ChAdOx1 nCoV-19 vaccination from February 1, until May 21, 2021. Cases with reports from the Greifswald laboratory were analysed in detail. FINDINGS: PF4 antibody tests were available for 69 suspected TTS cases reported to the Paul-Ehrlich Institute, of whom 52 patients fulfilled the BC case definition; 37 (71%) women, 15 (29%) men, median age 46·0 years (interquartile range 31·0-60·3 years). Cerebral venous sinus thrombosis was confirmed in 37 (71%), (additional) multiple thromboses in 19 (37%) patients. Twelve patients died. Non-survivors showed lower platelet counts compared to survivors (median nadir 15,000/µL vs 49,000/µL; p<0·0001). Combined anti-PF4/heparin IgG ELISA and PF4-dependent platelet activation testing yielded sensitivity of 96% (95% confidence interval 87-100%) and specificity of 77% (50-93%) for TTS. Four patients with thrombocytopenia but without thrombosis presented with severe headache or cerebral bleeding, explaining the lower specificity. INTERPRETATION: VITT has high mortality and can present with isolated thrombocytopenia, severe headache, and bleeding. Demonstration of platelet activating anti-PF4 IgG has high sensitivity for TTS and captures a wider spectrum of clinically relevant VITT than the current BC case definition. FUNDING: Deutsche Forschungsgemeinschaft: 374031971-TRR240; Domagk-Programm Universitätsmedizin Greifswald.

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INTRODUCTION: According to German legislation, reports of suspected serious adverse reactions (AR) associated with the donation of blood and its components are continuously being evaluated by the Paul-Ehrlich-Institut. This survey aimed at providing a more complete picture of the AR associated with the donation of blood and blood components. MATERIALS AND METHODS: Eligible donors had the opportunity to anonymously report all AR occurring during or after their last donation by completing an online questionnaire. Reported AR were classified according to the Standard for Surveillance of Complications Related to Blood Donation. Donors' self-assessment of AR seriousness was compared with the official severity classification as laid down by German legislation. Besides a descriptive statistical analysis, a multiple logistic analysis was performed to identify risk factors for AR. RESULTS: A total of 8,138 data records were evaluated. Slightly more males (57.9%) participated in the survey and, except for donors aged ≥60 years, all age groups were equally represented. The majority of participants were whole blood donors (85.4%), repeat donors (97.2%), and stayed under observation in the blood establishment (BE) for more than 5 min (63.1%) after donation. Most participants did not report any reaction (72.5%), whereas 2,237 reported at least one AR (27.5%), 475 of whom underwent apheresis and 1,762 donated whole blood. Most AR occurred after leaving the BE (64.4%). Only a minority of participants required medical treatment (5.1%) or assessed the experienced AR as serious (3.9%). The most frequently reported donor AR were haematoma and other local reactions (57.6%). Vasovagal reactions without and with loss of consciousness were developed in 17 and 2% of the participants, respectively, whilst 7.6% experienced citrate reactions. New AR (i.e., allergic reactions and symptoms associated with iron deficiency) were reported as well. The occurrence of AR was linked to risk factors (i.e., female gender, young age, first-time donation, and thrombocytapheresis). DISCUSSION: This survey yielded a more comprehensive AR spectrum, revealed a prolonged time to symptom onset, and identified risk factors for AR. This novel information could be implemented in an amended informed consent addressing common and rare AR.

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BACKGROUND: The SARS-CoV-2 pandemic has challenged many of our current routine practices in the treatment and care of patients. Given the critical importance of blood donation and transfusion we analyzed 92 blood samples of individuals infected with SARS-CoV-2 stratified by symptoms. STUDY DESIGN AND METHODS: We therefore tested blood samples for SARS-CoV-2 via RT-PCR targeting the E gene. In addition, we tested each blood sample for anti-SARS-CoV-2 IgG antibodies via ELISA and performed plaque reduction neutralization tests. RESULTS: SARS-CoV-2 RNA was absent in the blood of mild to asymptomatic patients (57 individuals) and only detectable in individuals with severe COVID-19 who were admitted to the intensive care unit (35 individuals) (n = 6/92 [6.5%]; p = 0.023 Fisher's exact test). Interestingly, anti-spike IgG antibodies were not significantly higher in intensive care unit patients compared to mild patients, but we found that their neutralizing capacity was disproportionately increased (p < 0.001). CONCLUSION: Our observations support the hypothesis that there are no potential hazards from blood or plasma transfusion of SARS-CoV-2-positive individuals with mild flu-like symptoms and more importantly of asymptomatic individuals.

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Oral swabs, sputum, and blood samples from 18 asymptomatic and symptomatic patients with SARS-CoV-2 infection were examined using RT-PCR testing in order to assess the risk of transfusion-related transmission. In asymptomatic patients as well as patients with flu-like symptoms and fever, no SARS-CoV-2 RNA could be detected in the blood or serum despite a clearly positive result in all throat swabs. As patients with symptoms of infectious disease will not be admitted to blood donation, the risk for transfusion transmission of SARS-CoV-2 seems to be negligible.

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BACKGROUND AND OBJECTIVES: Assessment of HBV-NAT testing compared to HBsAg and anti-HBc screening in German blood establishments for the period 2008-2015. MATERIALS AND METHODS: Blood donations screened for HBsAg and anti-HBc along with HBV-NAT were evaluated. Sensitivity of HBsAg and HBV-NAT tests was compared in 30 HBV seroconversion panels and with the viral load of the NAT-only cases. Residual risk for HBV in the WP was modelled. RESULTS: A total of 45 270 111 donations were evaluated. There were 29 NAT-only cases in the HBsAg-negative HBV-WP, one by ID-NAT and 28 by MP-NAT. MP-NAT, on average, showed higher sensitivity than HBsAg testing: MP-NAT-LoD of 146 IU/ml vs. 362 IU/ml HBV DNA for positive HBsAg detection (range 135-1502 IU/ml), resulting in 3·1 days (range 2·0-4·8 days) earlier HBV detection. Viral loads of the NAT-only cases confirmed the sensitivity of the HBV tests in the seroconversion study. One HBsAg-negative case was due to a new HBsAg mutant combination. There was one HBsAg-reactive only case. In addition, HBV incidence in the HBV-WP included 41 HBsAg-/HBV-NAT-positives and three HBV transmission cases. The residual risk for HBsAg was estimated to be 1:1 619 419-1 268 474 compared to 1:2 793 365-2 134 702 for MP-NAT. Within chronic HBV (HBsAg-/anti-HBc-positive and MP-NAT-negative) 70% were ID-NAT positive at low viral load (median 20 IU/ml). Among anti-HBc-only, supplementary ID-NAT detected 23 occult HBV infections. CONCLUSIONS: In the HBV-WP, MP-NAT provided a higher sensitivity than HBsAg testing, obtained a considerably higher yield and reduced the risk for HBV transmission. In later HBV stages, anti-HBc screening and HBV-ID-NAT intercepted potentially infectious donations.

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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.

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BACKGROUND AND OBJECTIVES: In Germany, in addition to standard blood donor screening, further mandatory tests were introduced for HCV-RNA, HIV-1-RNA and for anti-HBc. Screening for HBV-DNA is optional. This study investigates the benefits of these additional tests for the detection of HIV, HCV, and HBV infections among German blood donors. MATERIALS AND METHODS: From 2008 to 2015 we collected data on blood donations exclusively testing NAT positive (NAT yield) or reactive in only one of the screening assays. Assuming a Poisson distribution, we calculated NAT yield/reactive only rates on a per donation basis (number of yield/reactive only cases divided by the number of donations tested in the period under review) with 95% confidence intervals. RESULTS: Responding establishments covered 95% of the donations. We identified 20 HIV-1-NAT, 61 HCV-NAT and 29 HBV-NAT yield cases among approximately 46 million blood donations tested corresponding to 0·43 HIV-1 NAT, 1·32 HCV-NAT, and 0·64 HBV-NAT yield cases per million blood donations tested. For one HBsAg reactive only case and 23 anti-HBc reactive only cases in repeat donors, infection was confirmed by ID-NAT which translates into 0·02 and 0·55 cases per million donations tested. During the 8-year-observation period, one HIV-1, no HCV and four HBV transmissions associated with donations in the viremic pre-seroconversion window period were reported. CONCLUSION: Annually, NAT screening alone detected 2·5 HIV-1, 7·6 HCV, and 3·6 HBV infectious donations; anti-HBc screening alone identified 2·9 infectious donations of repeat donors with occult HBV infection. Overall, the survey results support that the currently practiced donor HIV/HCV/HBV screening strategy in Germany does ensure a high standard of blood safety.

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BACKGROUND: Benefits and risks of liberal and restrictive transfusion regimens are under on-going controversial discussion. This systematic review aimed at assessing both regimens in terms of pre-defined outcomes with special focus on patients undergoing major orthopaedic surgery. METHODS: We performed a literature search for mortality, morbidity and related outcomes following peri-operative blood transfusion in patients with major orthopaedic surgery in electronic databases. Combined outcome measure estimates were calculated within the scope of meta-analyses including randomised clinical trials comparing restrictive versus liberal blood transfusion regimens (e.g. MH risk ratio, Peto odds ratio). RESULTS: A total of 880 publications were identified 15 of which were finally included (8 randomised clinical trials (RCTs) with 3,693 patients and 6 observational studies with 4,244,112 patients). Regarding RCTs, no significant differences were detected between the transfusion regimes for all primary outcomes (30-day mortality, thromboembolic events, stroke/transitory ischaemic attack, myocardial infarction, wound infection and pneumonia) and a secondary outcome (length of hospital stay), whereas there was a significantly reduced risk of receiving at least one red blood concentrate under a restrictive regimen. CONCLUSION: The results of this systematic review do not suggest an increased risk associated with either a restrictive or a liberal transfusion regimen in patients undergoing major orthopaedic surgery.

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Hepatitis E virus (HEV) infections may be acquired through transfusion of blood components. As transfusion-transmitted infections mostly affect vulnerable individuals, measures to ensure the supply of safe blood components are under discussion. On the basis of the epidemiological situation in Germany, different testing strategy scenarios were investigated through simulation studies. Testing for HEV RNA by nucleic acid amplification technique (NAT) assays with a pool size of 96, and a 95% LoD of 20 IU/ml will result in an 80% reduction in expected HEV transmissions as well as of consequent chronic infections with subsequent severe complications.

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BACKGROUND: To assess the impact of safety measures, we compared reporting rates of transfusion-related reactions before and after the implementation of six measures in 1999, 2004, 2006, 2008 and 2009. METHODS: Reporting rates of transfusion-transmitted bacterial infection (TTBI), viral infection (TTVI) and immune-mediated transfusion-related acute lung injury (TRALI) were calculated on the basis of confirmed annual reports and distributed blood components. RESULTS: The introduction of HCV NAT testing caused a significant reduction of HCV reporting rate from 1:0.6 to 1:83.16 million administered blood components (p < 0.0001), donor screening for antibodies to hepatitis B core antigen caused a reduction of HBV reporting rate from 1:2.90 to 1:10.70 million units (p = 0.0168). A significant reduction from 1:0.094 to 1:2.42 million fresh frozen plasma (FFP) units could also be achieved by risk minimisation TRALI measures (p < 0.0001). Implementation of pre-donation sampling did not result in a significant decrease in TTBI, whereas limitation of shelf life for platelet concentrate (PC) minimised the TTBI reporting rate from 1:0.088 to 1:0.19 million PC units (p = 0.041). For HIV NAT pool testing, no significant reduction in HIV transmission was found due to very low reporting rates (1:10 million versus 1:27 million blood components, p = 0.422). CONCLUSION: On the basis of haemovigilance data, a significant benefit could be demonstrated for four of six implemented safety measures.

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Cell-based medicinal products (CBMPs), a category of advanced-therapy medicinal products (ATMPs), are authorised for the European market by the European Commission by means of the centralized marketing authorisation. By conforming to the German Medicinal Products Act (Sec. 4b AMG), national authorisation can be granted by the Paul-Ehrlich-Institut in Germany exclusively for ATMPs not based on a routine manufacturing procedure. In both procedures, quality, efficacy, and safety are evaluated and the risk-benefit balance is assessed. For the centralised procedure, mainly controlled clinical trial data must be submitted, whereas the requirements for national procedures could be modified corresponding to the stage of development of the ATMP. After marketing authorization, the marketing authorization/license holder is obligated to report all serious adverse reactions to the competent authority and to provide periodic safety update reports. If necessary, post-authorization safety studies could be imposed. On the basis of these regulatory measures, the safety of advanced therapies can be monitored and improved.

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BACKGROUND: Increased reporting of intravenous immunoglobulin (IVIG)-related hemolytic reactions (HRs) triggered an investigation by the German and Swiss health authorities to identify potential risk factors. STUDY DESIGN AND METHODS: From the EudraVigilance database HRs reported between 2008 and 2013 were retrieved for seven IVIG preparations. HRs were classified as mild to moderate (hemoglobin [Hb] decline < 2 g/dL)] or severe (Hb decline > 2 g/dL) and separately analyzed for IVIG doses of less than 2 g/kg body weight and 2 g/kg body weight or more. It was assessed whether HR reporting rates correlate with the isoagglutinin content of the different preparations. RESULTS: Of 569 HR cases retrieved, 103 cases were excluded due to insufficient data, leaving 466 for analysis. Ninety-three cases were classified as mild to moderate and 373 as severe. Approximately 80% of the severe HRs concerned patients with blood group A and only three patients with blood group O. Testing of isoagglutinin titers revealed substantial differences between the seven preparations. IVIG products with high anti-A/anti-B titers (≥32) had elevated HR reporting rates, particularly when cumulative doses at least 2 g/kg were administered. CONCLUSION: The isoagglutinin content of IVIGs correlates with the risk for HRs. Exclusion of high-titer donations and manufacturing steps that deplete isoagglutinins should be considered for risk mitigation. In patients with blood groups A or AB receiving doses of at least 2 g/kg, the use of IVIG batches with low isoagglutinin titers should be considered to prevent HRs.

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BACKGROUND: Several publications describe HIV-1 RNA false-negative results or viral load underquantitation associated with Communauté Européenne(CE)-marked qualitative or quantitative nucleic acid amplification technique (NAT) assays. 6 cases occurred during blood screening in Germany, with 2 of them causing HIV-1 transmissions to recipients of blood components. The implicated NAT assays were mono-target assays amplifying in different viral genome regions (gag or long terminal repeat). METHODS: Specimens characterized by HIV-1 NAT underquantitation or false-negative NAT results were comparatively investigated in CE-marked HIV-1 NAT systems of different design to identify potential reasons. The target regions of the viral nucleic acids were sequenced and these sequences compared to primers and probes of the assays. Potential risk minimization measures were considered for quantitative and blood-screening HIV-1 NAT systems. RESULTS: Nucleotide sequencing of the viral target region in cases of HIV-1 RNA underquantitation or false-negative test results revealed new HIV-1 variants that were mismatched with primers and probes used in some mono-target assays. So far, dualtarget NAT assays have not been associated with mismatch-based false-negative test results. From 2015, the Paul Ehrlich Institute will request HIV-1 NAT assays of dual-target design or an analogous solution for further reducing the risk in blood screening. CONCLUSION: HIV differs from other blood-borne viruses with regard to its fast evolution of new viral variants. The evolution of new sequences is hardly predictable; therefore, NAT assays with only 1 target region appear to be more vulnerable to sequence variations than dual-target assays. The associated risk may be higher for HIV-1 NAT assays used for blood screening compared to quantitative assays used for monitoring HIV-1-infected patients. In HIV-1 screening NAT assays of dual-target design may adequately address the risk imposed by new HIV-1 variants.

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A first systematic study upon the preparation and exploration of a series of iron 10-thiacorroles with simple halogenido (F, Cl, Br, I), pseudo-halogenido (N3 , I3 ) and solvent-derived axial ligands (DMSO, pyridine) is reported. The compounds were prepared from the free-base octaethyl-10-thiacorrole by iron insertion and subsequent ligand-exchange reactions. The small N4 cavity of the ring-contracted porphyrinoid results in an intermediate spin (i.s., S=3/2) state as the ground state for the iron(III) ion. In most of the investigated cases, the i.s. state is found unperturbed and independent of temperature, as determined by a combination of X-ray crystallography and magnetometry with (1) H NMR-, EPR-, and Mössbauer spectroscopy. Two exceptions were found. The fluorido iron(III) complex is inhomogenous in the solid and contains a thermal i.s. (S=3/2)→high spin (h.s., S=5/2) crossover fraction. On the other side, the cationic bis(pyridine) complex resides in the expected low spin (l.s., S=1/2) state. Chemically, the iron 10-thiacorroles differ from the iron porphyrins mainly by weaker axial ligand binding and by a cathodic shift of the redox potentials. These features make the 10-thiacorroles interesting ligands for future research on biomimetic catalysts and model systems for unusual heme protein active sites.

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