Adequate IVIG dosing is associated with an improved long-term outcome in secondary immunodeficiency: A prospective, non-interventional study.

OBJECTIVE: To assess the safety, tolerability, and effectiveness of the intravenous immunoglobulin (IVIG) Intratect 50 g/L in immunoglobulin replacement therapy (IgRT) in a prospective, large-scale non-interventional study (NIS). The analysis focused upon patients with secondary immunodeficiency (SID), the most frequent indication for IgRT in this NIS. MATERIALS AND METHODS: Patients were enrolled at 123 centers in Germany. Each patient received IVIG as prescribed by the physician, guided by the Summary of Product Characteristics. Data were acquired from medical records and patients' questionnaires. RESULTS: In the NIS, 3,563 patients were documented. The main indication for IgRT was SID (73.2%), followed by primary immunodeficiency (14.7%), immune thrombocytopenia (5.8%), and other indications (6.2%). Among the SID patients, 52.9% were male, mean age was 66.5 years, and most (63.8%) were IVIG-naïve. Their annual infection rate improved from 3.7 before documentation in the NIS to 1.1 during the first year of the study. IgG trough plasma levels increased during treatment (> 6 g/L: 44.5% of SID patients at study entry and 64.8% in long-term treatment) and were associated with a trend toward reduced infection rate (p = 0.08). A 1-year infection analysis showed a significantly lower infection risk in the medium- and high-dose groups than in the low-dose group (p = 0.028 and p = 0.017, respectively). Patients' treatment satisfaction and quality of life improved from baseline. Adverse drug reactions (ADRs) in SID occurred at a low frequency with 0.8% at infusion level. On the patient level, ADRs occurred in 251 (15.3%) SID patients, with chills (7.4%) and pyrexia (0.9%) reported most frequently. CONCLUSION: Effectiveness, safety, and quality of life confirmed the positive benefit-risk profile of IgRT. Higher IVIG dosages per body weight led to higher IgG plasma trough levels, in turn leading to reduced infection rates. Obese patients may need body-weight-adjusted treatment to reduce the risk of infection.

Varicella Zoster Virus-Specific Hyperimmunoglobulin in the Adjuvant Treatment of Immunocompromised Herpes Zoster Patients: A Case Series.

INTRODUCTION: Immunocompromised patients are at increased risk for herpes zoster (HZ)-associated complications. Despite standard therapy with systemic antiviral drugs and analgesics, complications are frequently encountered, including generalization of lesions or persistent neuropathic pain, so-called post-herpetic neuralgia (PHN). Given the scarcity of literature and awareness of therapeutic options to improve patient outcomes, especially for vulnerable patient groups, here we describe a strategy based on early intensification of treatment with a varicella zoster virus-specific hyperimmunoglobulin (VZV-IgG), which is approved in the adjuvant treatment of HZ. METHODS: For this case series, we selected four cases of HZ in patients with impaired immunity due to hemato-oncologic disease or immunosuppressive treatment who presented with either existing generalized lesions and/or severe pain or with other risk factors for a complicated HZ course such as PHN. They were considered to be representative examples of different patient profiles eligible for intensification of treatment by the addition of VZV-IgG to virostatic therapy. CASE REPORT: All patients showed a rapid response to combined treatment with VZV-IgG and a virostatic agent. In two patients who had generalized lesions, the formation of new lesions ceased 1 day after VZV-IgG infusion. One patient, with mantle cell lymphoma, achieved complete healing of the lesions 9 days after diagnosis of HZ, a rare occurrence compared to similar cases or cohorts. A patient with HZ in the cervical region showed a good response after a single dose of VZV-IgG. None of the patients developed post-zoster-related complications. Combination therapy of a virostatic agent and VZV-IgG was well tolerated in these four cases. CONCLUSION: This case series demonstrates highly satisfactory treatment effectiveness and tolerability for VZV-IgG in the adjuvant treatment of immunocompromised HZ patients and supports early intensification of HZ therapy in patients at high risk of severe disease progression.

Benefits of immunoglobulin substitution in primary and secondary immunodeficiencies: Interim analysis of a prospective, long-term non-interventional study.

OBJECTIVE: To assess the safety, tolerability, and effectiveness of the intravenous immunoglobulin (IVIG) Intratect 100 g/L in a prospective, large-scale non-interventional study (NIS) of patients with a wide range of antibody deficiencies as well as other indications for IVIG, risk factors, and frequency of pre-treatments. MATERIALS AND METHODS: Patients were enrolled at 53 practices and clinics in Germany. After recording of baseline information, each patient was treated according to need, as judged by the physician and guided by the SmPC. Relevant data were acquired from medical records, and the patients completed questionnaires to assess treatment satisfaction and quality of life (QoL). RESULTS: At cut-off for this interim analysis, 488 patients were enrolled (planned: 1,000). 47% were male, age 16 - 91 (median 61) years, with treatment durations up to 2,225 (median 282) days. Indications were primary (32%) and secondary (61%) immunodeficiencies, immune thrombocytopenia (4%), and others (3%). More than 92% of physicians recorded very good effectiveness and satisfaction. Patient satisfaction and QoL increased with time from baseline. Initially, 31% of the SID patients had inadequate IgG trough levels (< 4 g/L), including patients with (37%) and without (63%) previous IVIG treatment. Despite a relatively low IVIG dose (median 0.2 g/kg), trough levels improved: after 3 infusions, only 22% of patients had trough levels < 4 g/L, with a plateau below 17% after 6 infusions. Adverse reactions were observed at a rate of 3% per infusion, whereas 0.08% accounted for serious reactions. CONCLUSION: Effectiveness, safety, patient satisfaction, and QoL were good, confirming the positive benefit-risk profile of the IVIG.

Cytochrome c Oxidase Biogenesis and Metallochaperone Interactions: Steps in the Assembly Pathway of a Bacterial Complex.

Biogenesis of mitochondrial cytochrome c oxidase (COX) is a complex process involving the coordinate expression and assembly of numerous subunits (SU) of dual genetic origin. Moreover, several auxiliary factors are required to recruit and insert the redox-active metal compounds, which in most cases are buried in their protein scaffold deep inside the membrane. Here we used a combination of gel electrophoresis and pull-down assay techniques in conjunction with immunostaining as well as complexome profiling to identify and analyze the composition of assembly intermediates in solubilized membranes of the bacterium Paracoccus denitrificans. Our results show that the central SUI passes through at least three intermediate complexes with distinct subunit and cofactor composition before formation of the holoenzyme and its subsequent integration into supercomplexes. We propose a model for COX biogenesis in which maturation of newly translated COX SUI is initially assisted by CtaG, a chaperone implicated in CuB site metallation, followed by the interaction with the heme chaperone Surf1c to populate the redox-active metal-heme centers in SUI. Only then the remaining smaller subunits are recruited to form the mature enzyme which ultimately associates with respiratory complexes I and III into supercomplexes.

Unification of the copper(I) binding affinities of the metallo-chaperones Atx1, Atox1, and related proteins: detection probes and affinity standards.

Literature estimates of metal-protein affinities are widely scattered for many systems, as highlighted by the class of metallo-chaperone proteins, which includes human Atox1. The discrepancies may be attributed to unreliable detection probes and/or inconsistent affinity standards. In this study, application of the four Cu(I) ligand probes bicinchoninate, bathocuproine disulfonate, dithiothreitol (Dtt), and glutathione (GSH) is reviewed, and their Cu(I) affinities are re-estimated and unified. Excess bicinchoninate or bathocuproine disulfonate reacts with Cu(I) to yield distinct 1:2 chromatophoric complexes [Cu(I)L(2)](3-) with formation constants ß(2) = 10(17.2) and 10(19.8) m(-2), respectively. These constants do not depend on proton concentration for pH ≥7.0. Consequently, they are a pair of complementary and stable probes capable of detecting free Cu(+) concentrations from 10(-12) to 10(-19) m. Dtt binds Cu(I) with K(D) ∼10(-15) m at pH 7, but it is air-sensitive, and its Cu(I) affinity varies with pH. The Cu(I) binding properties of Atox1 and related proteins (including the fifth and sixth domains at the N terminus of the Wilson protein ATP7B) were assessed with these probes. The results demonstrate the following: (i) their use permits the stoichiometry of high affinity Cu(I) binding and the individual quantitative affinities (K(D) values) to be determined reliably via noncompetitive and competitive reactions, respectively; (ii) the scattered literature values are unified by using reliable probes on a unified scale; and (iii) Atox1-type proteins bind Cu(I) with sub-femtomolar affinities, consistent with tight control of labile Cu(+) concentrations in living cells.