Role of Immunoglobulin Therapy to Prevent and Treat Infections

Immunization technologies: Time to consider new preventative solutions for respiratory syncytial virus infections

New technologies for the prevention of infectious diseases are emerging to address unmet medical needs, in particular, the use of long-acting monoclonal antibodies (mAb) to prevent Respiratory Syncytial Virus (RSV) lower respiratory tract disease in infants during their first RSV season. The lack of precedent for mAbs for broad population protection creates challenges in the assessment of upcoming prophylactic long-acting mAbs for RSV, with associated consequences in legislative and registration categorization, as well as in recommendation, funding, and implementation pathways. We suggest that the legislative and regulatory categorization of preventative solutions should be decided by the effect of the product in terms of its impact on the population and health-care systems rather than by the technology used or its mechanism of action. Immunization can be passive and active, both having the same objective of prevention of infectious diseases. Long-acting prophylactic mAbs work as passive immunization, as such, their recommendations for use should fall under the remit of National Immunization Technical Advisory Groups or other relevant recommending bodies for inclusion into National Immunization Programs. Current regulations, policy, and legislative frameworks need to evolve to embrace such innovative preventative technologies and acknowledge them as one of key immunization and public health tools.

Blood-derived product therapies for SARS-CoV-2 infection and long COVID

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is capable of large-scale transmission and has caused the coronavirus disease 2019 (COVID-19) pandemic. Patients with COVID-19 may experience persistent long-term health issues, known as long COVID. Both acute SARS-CoV-2 infection and long COVID have resulted in persistent negative impacts on global public health. The effective application and development of blood-derived products are important strategies to combat the serious damage caused by COVID-19. Since the emergence of COVID-19, various blood-derived products that target or do not target SARS-CoV-2 have been investigated for therapeutic applications. SARS-CoV-2-targeting blood-derived products, including COVID-19 convalescent plasma, COVID-19 hyperimmune globulin, and recombinant anti-SARS-CoV-2 neutralizing immunoglobulin G, are virus-targeting and can provide immediate control of viral infection in the short term. Non-SARS-CoV-2-targeting blood-derived products, including intravenous immunoglobulin and human serum albumin exhibit anti-inflammatory, immunomodulatory, antioxidant, and anticoagulatory properties. Rational use of these products can be beneficial to patients with SARS-CoV-2 infection or long COVID. With evidence accumulated since the pandemic began, we here summarize the progress of blood-derived product therapies for COVID-19, discuss the effective methods and scenarios regarding these therapies, and provide guidance and suggestions for clinical treatment.

Insights into Facilitated Subcutaneous Immunoglobulin Use in Patients with Secondary Immunodeficiency Diseases: A FIGARO Subgroup Analysis

The Facilitated Immunoglobulin Administration Registry And Outcomes (FIGARO) Study was a European, multicenter, prospective, observational study conducted across Europe designed to provide insights on the clinical use and tolerability of facilitated subcutaneous immunoglobulin (fSCIG). Data herein are reported for the cohort of patients with secondary immunodeficiency (SID), with a subgroup analysis by age. The SID cohort included 31 patients: 1 pediatric, 15 adult, and 15 older adult patients. Over the 36-month observation period, the median monthly dose of fSCIG (30 g) and median monthly infusion volume per patient (300 mL) remained constant in both adult-age cohorts. Serum trough levels tended to increase over time. Most patients required only one infusion site and could receive the full dose every 3-4 weeks. There was a trend toward self-administration at home. In the adult group, infusion site inflammation and headache were reported at the inclusion visit (n = 1 each), with no adverse drug reactions reported at any of the follow-up visits. No acute severe bacterial infections were reported during the study follow-up. These results demonstrate the feasibility and tolerability of fSCIG use in patients with SID and the flexibility of administration settings including self-administration at home in patients aged ≥65 years.

A Systematic Review on the Prevention and Control of Opportunistic Infections in Patients With Chronic Lymphocytic Leukemia Complicated by Richter's Transformation

Chronic lymphocytic leukemia (CLL) is one of the most commonly occurring types of leukemia among the elderly population, contributing to an increased vulnerability to infections that are especially prolific in the immunosuppressed and the risk of rapid progression of the disease into a more aggressive manifestation of large cell lymphoma, a process called Richter's Transformation (RT). CLL alone predisposes patients to develop infections; however, the additional complication of RT decreases survival and makes the prevention and control of infection for the CLL patient even more challenging. However, research that exists on preventing and controlling infection in CLL patients with RT is relatively limited. In most cases, studies have focused on the prevention of infection in CLL patients in general and with no reference to the progression of RT. Considering the dearth of research on infection prevention and control for patients with CLL complicated by RT specifically, the following review examines existing research in addressing the prevention and control of infection in CLL patients with RT and patients in general. The authors explored multiple databases such as PubMed, Google Scholar, and Science Direct. The ultimate focus of this study was to lay a fundamental understanding in preventing and controlling infection in CLL patients. After analyzing several studies, it can be concluded that identifying infections, even if rare, is a crucial aspect of managing CLL patients. A broad range of differential diagnoses should be sought in cases presenting with refractory CLL as well and management of infections before, during, or after CLL treatment should be considered.

Immunoglobulin G in Platelet-Derived Wound Healing Factors

We intended to reformulate an existing platelet-derived wound healing formula to target each phase of the healing wound with the appropriate phase-specific molecules. A decreased perfusion of the skin, often associated with conditions such as thalassemia, sickle cell disease, diabetes mellitus, and chronic vascular disease, is the most common etiology of cutaneous ulcers and chronic wounds. We had previously shown that a PDWHF topically applied to a chronic nonhealing ulcer of a β-thalassemia homozygote stimulated and accelerated closure of the wound. The PDWHF was prepared from a pooled platelet concentrate of a matching blood group, consisting of a combination of platelet α-granule-derived factors. Processing of the apheresis-pooled platelets yielded various amounts of proteins (3.36 g/mL ± 0.25 (SD) (N = 10)) by the better lysis buffer method. Immunoglobulin G was found to be the most abundant α-granule-secreted protein. Equally broad quantities of the IgG (10.76 ± 12.66% (SD) (N = 10)) and IgG/albumin ratios (0.6 ± 0.4 (SD) (N = 10)) were quantified. We have developed a method using a reformulated lysis buffer followed by size exclusion chromatography and affinity chromatography to extract, identify, quantify, and purify IgG from activated platelets. IgG purification was confirmed by Western blot and flow cytometry. It was thought unlikely that the platelet IgG could be accounted for by adsorption of plasma protein, though the variable quantities could account for diversity in wound healing rates. The IgG could protect the wound even from subclinical infections and functionally advance healing. It may be useful in the management of skin ulcers in the early phase of wound healing.