Subcutaneous immunoglobulin replacement therapy in patients with immunodeficiencies - impact of drug packaging and administration method on patient reported outcomes.

BACKGROUND: Here, the perspective of patients with primary and secondary immunodeficiency receiving subcutaneous immunoglobulin (SCIg) via introductory smaller size pre-filled syringes (PFS) or vials were compared. METHODS: An online survey was conducted in Canada by the Association des Patients Immunodéficients du Québec (APIQ) (10/2020-03/2021). Survey questions included: reasons for choosing SCIg packaging and administration methods, training experiences, infusion characteristics, and switching methods. The survey captured structured patient-reported outcomes: treatment satisfaction and its sub-domains, symptom state, general health perception, and physical and mental function. Respondents using PFS were compared with vial users, overall and stratified by their administration method (pump or manual push). RESULTS: Of the 132 total respondents, 66 respondents used vials, with 38 using a pump and 28 using manual push. PFS (5 and 10 mL sizes) were being used by 120 respondents, with 38 using a pump and 82 using manual push. PFS users were associated with a 17% lower median (interquartile range) SCIg dose (10 [8, 12] vs. 12 [9, 16] g/week, respectively), a significantly shorter infusion preparation time (15 [10, 20] vs. 15 [10, 30] mins, respectively), and a trend for shorter length of infusion (60 [35, 90] vs. 70 [48, 90] mins, respectively) compared with those on vials. Patient-reported treatment satisfaction scores were overall similar between vial and PFS users (including on the domains of effectiveness and convenience), except for a higher score for vials over PFS on the domain of global satisfaction (p=0.02). CONCLUSIONS: Consistent with prescribing that reflects a recognition of less wastage, PFS users were associated with a significantly lower SCIg dose compared with vial users. PFS users were also associated with shorter pre-infusion times, reflecting simpler administration mechanics compared with vial users. Higher global satisfaction with treatment among vial users compared with PFS users was consistent with users being limited to smaller PFS size options in Canada during the study period. Patient experience on PFS is expected to improve with the introduction of larger PFS sizes. Overall, treatment satisfaction for SCIg remains consistently high with the introduction of PFS packaging compared with vials.

Population pharmacokinetics of immunoglobulin G after intravenous, subcutaneous, or hyaluronidase-facilitated subcutaneous administration in immunoglobulin-naive patients with primary immunodeficiencies.

Immunoglobulin G (IgG) replacement therapy is the standard of care for patients with primary immunodeficiencies with antibody deficiencies. Intravenous (IVIG), subcutaneous (SCIG), and hyaluronidase-facilitated subcutaneous immunoglobulin (fSCIG) therapies differ in their pharmacokinetic (PK) profiles, administration routes, and dosing regimens. Information on use of subcutaneous therapy in IgG treatment-naive patients is limited. This study used population pharmacokinetic (popPK) model-based simulations to characterize IgG PKs in IgG-naive patients with varying disease severity across several IVIG, SCIG, and fSCIG dosing regimens. An integrated popPK model, developed and validated using data from eight clinical trials, was utilized to simulate scenarios that varied by therapy, loading regimen, maintenance dose (equivalent to 400, 600, or 800 mg/kg every 4 weeks [Q4W]), and baseline endogenous total IgG concentration (1.5 or 4.0 g/L). Simulations were performed for age groups of 2-<6, 6-<12, 12-<18, and ≥18 years. Steady-state serum trough IgG concentrations (Cmin,ss), proportion of patients achieving Cmin,ss ≥ 7 g/L, and days taken to reach this threshold were summarized. SCIG provided greater mean Cmin,ss values than IVIG and fSCIG for any scenario. Across all therapies, Cmin,ss tended to increase with age, dose, and endogenous concentration. Although the findings are model-based and not a summarization of real-world observations, doses ≥ 800 mg/kg Q4W with corresponding loading regimens are likely to be clinically appropriate for achieving target IgG concentrations in treatment-naive patients in a timely manner, especially at low endogenous starting concentrations. Therapy-specific dose adjustment based on baseline endogenous IgG concentration, clinical status, and patient characteristics may be warranted.

Benefits of Immunoglobulin (Ig) Replacement Therapy for Primary and Secondary Immunodeficiency in Chronic Rhinosinusitis.

This is the first study to examine chronic rhinosinusitis (CRS) outcomes after starting immunoglobulin (Ig) replacement therapy for patients with primary (PID) and secondary immunodeficiency (SID). This is a retrospective review of patients diagnosed with CRS from 2018 to 2022 prior to initiating Ig therapy for the treatment of PID or SID. Outcomes included medication use and Sinonasal Outcome Test (SNOT-22) scores. Ten patients met the inclusion criteria. PID and SID patients had a decrease in antibiotics (PID: 9.40 to 3.20, P = .05, SID: 8.20 to 2.00, P = .04) and steroids (PID: (5.40 to 0.60; P = .06; SID: 2.20 to 0.20, P = .047) prescribed in the year after Ig compared to the year prior. Patients with SID had a decrease in mean SNOT-22 scores by 12 months after Ig (47.50 to 20.50, P = 0.03). Patients receiving Ig for PID and SID showed decreased medication use and SID patients experienced subjective improvement in CRS symptoms in year-over-year comparison.

The Experiences of Children with Primary Immunodeficiency Who Receive Immunoglobulin Subcutaneously Instead of Intravenously.

BACKGROUND: Children with primary immunodeficiency disorder have begun receiving subcutaneous immunoglobulin (SCIg) instead of intravenous immunoglobulin (IVIg). So, we aim to explore the experiences of primary immunodeficiency children with regard to receiving SCIg instead of IVIg. METHOD: We adopted a phenomenological approach in 2022 in Turkey using semi-structured interviews. We recruited 15 participants using the purposive sampling method. RESULTS: The main theme was the sweetness and bitterness of living with SCIg. The first subtheme was sweetness (sense of freedom, having a normal life, saving time, ease of use, and feeling better). The second subtheme was bitterness (worries about taking responsibility for injection, impaired body image due to abdominal edema, and minimal tolerable complications). DISCUSSION: The results show these children had more sweet experiences than bitter ones. Being flexible in choosing a method, teaching patients to apply it correctly, and providing enough time to cope are as reasons for this.

Clinical outcomes of immunoglobulin treatment for patients with secondary antibody deficiency: Data from the Ontario immunoglobulin treatment case registry.

BACKGROUND: Despite the increasing number of cases of secondary antibody deficiency (SAD) and immunoglobulin (Ig) utilization, there is a paucity of data in the literature on clinical and patient-reported outcomes in this population. OBJECTIVE: To describe immunoglobulin utilization patterns, clinical and patient-reported outcomes in patients with SAD on immunoglobulin replacement therapy (IgRT). METHODS: A cross-sectional study of patients with secondary antibody deficiency enrolled in the Ontario Immunoglobulin Treatment (ONIT) Case Registry from June 2020 to September 2022 was completed. Demographics, comorbidities, indications for immunoglobulin treatment, clinical infections at baseline and post IgRT, and patient-reported outcomes were collected and analyzed. RESULTS: There were 140 patients (58 males; 82 females; median age 68) with SAD during the study period; 131 were on subcutaneous Ig (SCIG) and 9 were on intravenous Ig (IVIG). The most common indication was chronic lymphocytic leukemia (CLL) (N = 52). IgRT reduced the average annual number of infections by 82.6%, emergency room (ER) visits by 84.6%, and hospitalizations by 83.3%. Overall, 84.6% of patients reported their health as better compared to before IgRT. Among those patients who switched from IVIG to SCIG (N = 35), 33.3% reported their health as the same, and 62.9% reported their health as better. CONCLUSIONS: This study demonstrates that IgRT significantly improved clinical outcomes and patient-reported general health state in patients with SAD. This study also further supports the use of SCIG in patients with SAD.

Real-World Use, Safety, and Patient Experience of 20% Subcutaneous Immunoglobulin for Primary Immunodeficiency Diseases.

INTRODUCTION: The CORE study aimed to provide a detailed understanding of real-world immune globulin subcutaneous (human) 20% solution (Ig20Gly) utilization in patients with primary immunodeficiency diseases (PIDs) in Germany and Switzerland. METHODS: Patients with PIDs receiving a stable dose of any subcutaneous immunoglobulin for ≥ 3 months before enrollment were eligible for this multicenter (n = 5), phase 4, non-interventional, prospective, longitudinal cohort study. Besides baseline demographics and clinical characteristics, Ig20Gly utilization and safety data, and patient-reported outcomes (Life Quality Index/Treatment Satisfaction Questionnaire for Medication) were collected at baseline, 6 and 12 months. Statistical analysis was descriptive. RESULTS: Overall, 36 patients provided data at baseline [69.4% female; mean age: 41.6 years (7-78 years)]. Totals of 23 and 26 patients attended 6- and 12-month visits, respectively; 16 attended all three visits. One patient withdrew consent before 6-month follow-up. Median maximum infusion rates of Ig20Gly at baseline, 6 months, and 12 months were 26.7, 24.5, and 40.0 mL/h, respectively (10-60 mL/h). Infusion and dosing parameters remained consistent across time points: patients used a median of two infusion sites, primarily the abdomen, and all patients used an infusion pump; all but one infused at home and most self-administered Ig20Gly (80.8-83.3%) at once-weekly intervals (69.2-73.9%). During follow-up, 10 adverse events were reported: none were rated serious, while 2 were considered probably related to Ig20Gly. Total patient-reported outcome scores remained high throughout the study. CONCLUSION: The CORE study provides real-world evidence of the flexibility, feasibility, safety, and tolerability of Ig20Gly infusions, at mostly weekly intervals, over 1 year in patients with PIDs. TRIAL REGISTRATION: German Clinical Trials Register, DRKS00014562. Registered April 9, 2018, https://drks.de/search/en/trial/DRKS00014562.

Primary immunodeficiency diseases are rare diseases that make patients more likely to develop infections than the general population. Many patients with primary immunodeficiency diseases do not produce enough antibodies, which are an important part of the immune system that fight infection. Replacing antibodies is the main way to treat primary immunodeficiency diseases and reduce the risk of infection. Ig20Gly is a type of medication used to replace antibodies and treat primary immunodeficiency diseases. Patients receive Ig20Gly through a needle inserted under the skin and can learn to do this themselves at home. Ig20Gly can be delivered more quickly than other antibody treatments that are less concentrated. CORE was a study of 36 patients (children and adults) taking Ig20Gly for primary immunodeficiency diseases for 1 year in Germany and Switzerland. The aim of the study was to understand how patients use and experience Ig20Gly as part of their normal treatment. In this study, nearly all patients received Ig20Gly treatment at home, and most patients gave Ig20Gly to themselves once a week. A few patients developed serious bacterial infections while being treated with Ig20Gly, and patients were generally satisfied with the treatment. Overall, the CORE study describes how patients with primary immunodeficiency diseases use Ig20Gly in their daily lives, and shows that Ig20Gly treatment can be tailored to suit each patient's needs. Information from this study will help doctors to support patients in making decisions about their treatment.

A phase III randomized crossover trial of plerixafor versus G-CSF for treatment of WHIM syndrome.

BACKGROUNDWarts, hypogammaglobulinemia, infections, and myelokathexis (WHIM) syndrome is a primary immunodeficiency disorder caused by heterozygous gain-of-function CXCR4 mutations. Myelokathexis is a kind of neutropenia caused by neutrophil retention in bone marrow and in WHIM syndrome is associated with lymphopenia and monocytopenia. The CXCR4 antagonist plerixafor mobilizes leukocytes to the blood; however, its safety and efficacy in WHIM syndrome are undefined.METHODSIn this investigator-initiated, single-center, quadruple-masked phase III crossover trial, we compared the total infection severity score (TISS) as the primary endpoint in an intent-to-treat manner in 19 patients with WHIM who each received 12 months treatment with plerixafor and 12 months treatment with granulocyte CSF (G-CSF, the standard of care for severe congenital neutropenia). The treatment order was randomized for each patient.RESULTSPlerixafor was nonsuperior to G-CSF for TISS (P = 0.54). In exploratory endpoints, plerixafor was noninferior to G-CSF for maintaining neutrophil counts of more than 500 cells/µL (P = 0.023) and was superior to G-CSF for maintaining lymphocyte counts above 1,000 cells/µL (P < 0.0001). Complete regression of a subset of large wart areas occurred on plerixafor in 5 of 7 patients with major wart burdens at baseline. Transient rash occurred on plerixafor, and bone pain was more common on G-CSF. There were no significant differences in drug preference or quality of life or the incidence of drug failure or serious adverse events.CONCLUSIONPlerixafor was not superior to G-CSF in patients with WHIM for TISS, the primary endpoint. Together with wart regression and hematologic improvement, the infection severity results support continued study of plerixafor as a potential treatment for WHIM syndrome.TRIAL REGISTRATIONClinicaltrials.gov NCT02231879.FUNDINGThis study was funded by the Division of Intramural Research, National Institute of Allergy and Infectious Diseases.

Subcutaneous immunoglobulin 20% (Ig20Gly) treatment regimens in pediatric patients with primary immunodeficiencies - real-world data from the IG TATRY study.

BACKGROUND: Subcutaneous administration of immunoglobulins is associated with fewer systemic adverse events and easier infusion compared to intravenous administration. Ig20Gly is a 20% immunoglobulin formulation effective and safe in patients with primary immune deficiency diseases (PIDDs). Real-world data are scarce, therefore our study aimed to examine the real-life treatment regimen and clinical outcomes of Ig20Gly in Polish children with PIDDs. RESEARCHDESIGN: We retrospectively analyzed the medical documentation of 75 pediatric patients aged 0-17 years (mean 9.9) who received Ig20Gly (Cuvitru®; Baxalta US, Inc.; part of Takeda, MA, U.S.A.). RESULTS: The median exposure to treatment of the study population was 22.3 months. At the end of the study, 59 (78.7%) were still on Ig20Gly. The median monthly dose was 0.40 g/kg. The median treatment interval was 7.7 days. Most patients (96%) used one infusion site. The median infusion rate increased with patient age. The median IgG level in the study population, 8.0 g/L, was stable. There was one case of serious bacterial infection. CONCLUSION: This is the largest, long-term real-world study to date on the treatment patterns of Ig20Gly in pediatric patients with PIDDs. The results of this study support the feasibility and tolerability of Ig20Gly usage in PIDD patients across the pediatric age spectrum. TRIAL REGISTRATION: The trial is registered at ClinicalTrials.gov (NCT04636502).

Safety and Efficacy of Hizentra® Following Pediatric Hematopoietic Cell Transplant for Treatment of Primary Immunodeficiencies.

Primary immunodeficiency disease (PIDD) comprises a group of disorders of immune function. Some of the most severe PIDD can be treated with hematopoietic cell transplant (HCT). Hizentra® is a 20% liquid IgG product approved for subcutaneous administration in adults and children greater than 2 years of age with PIDD-associated antibody deficiency. Limited information is available on the use of Hizentra® in children following HCT for PIDD. A multicenter retrospective chart review demonstrated 37 infants and children (median age 70.1 [range 12.0 to 176.4] months) with PIDD treated by HCT who received Hizentra® infusions over a median duration of 31 (range 4-96) months post-transplant. The most common indication for HCT was IL2RG SCID (n = 16). Thirty-two patients switched from IVIG to SCIG administration, due to one or more of the following reasons: patient/caregiver (n = 17) or physician (n = 12) preference, discontinuation of central venous catheter (n = 16), desire for home infusion (n = 12), improved IgG serum levels following lower levels on IVIG (n = 10), and loss of venous access (n = 8). Serious bacterial infections occurred at a rate of 0.041 per patient-year while on therapy. Weight percentile increased by a mean of 16% during the observation period, with females demonstrating the largest gains. Mild local reactions were observed in 24%; 76% had no local reactions. One serious adverse event (death from sepsis) was reported. Hizentra® was discontinued in 15 (41%) patients, most commonly due to recovery of B cell function (n = 11). These data demonstrate that Hizentra® is a safe and effective option in children who have received HCT for PIDD.

Recommendations for Management of Secondary Antibody Deficiency in Multiple Myeloma.

Secondary antibody deficiency (SAD) is a subtype of secondary immunodeficiency characterized by low serum antibody concentrations (hypogammaglobulinemia) or poor antibody function. SAD is common in patients with multiple myeloma (MM) due to underlying disease pathophysiology and treatment-related immune system effects. Patients with SAD are more susceptible to infections and infection-related morbidity and mortality. With therapeutic advancements improving MM disease control and survival, it is increasingly important to recognize and treat the often-overlooked concurrent immunodeficiency present in patients with MM. The aims of this review are to define SAD and its consequences in MM, increase SAD awareness, and provide recommendations for SAD management. Based on expert panel discussions at a standalone meeting and supportive literature, several recommendations were made. Firstly, all patients with MM should be suspected to have SAD regardless of serum antibody concentrations. Patients should be evaluated for immunodeficiency at MM diagnosis and stratified into management categories based on their individualized risk of SAD and infection. Infection-prevention strategy education, early infection reporting, and anti-infective prophylaxis are key. We recommend prophylactic antibiotics or immunoglobulin replacement therapy (IgRT) should be considered in patients with severe hypogammaglobulinemia associated with a recurrent or persistent infection. To ensure an individualized and efficient treatment approach is utilized, patient's immunoglobin G concentration and infection burden should be closely monitored throughout treatment. Patient choice regarding route and IgRT treatment is also key in reducing treatment burden. Together, these recommendations and proposed management algorithms can be used to aid physician decision-making to improve patient outcomes.

Characteristics and Outcomes of Anti-interferon Gamma Antibody-Associated Adult Onset Immunodeficiency.

PURPOSE: Anti-interferon gamma antibody (AIGA) is a rare cause of adult onset immunodeficiency, leading to severe disseminated opportunistic infections with varying outcomes. We aimed to summarize the disease characteristics and to explore factors associated with disease outcome. METHODS: A systematic literature review of AIGA associated disease was conducted. Serum-positive cases with detailed clinical presentations, treatment protocols, and outcomes were included. The patients were categorized into controlled and uncontrolled groups based on their documented clinical outcome. Factors associated with disease outcome were analyzed with logistic regression models. RESULTS: A total of 195 AIGA patients were retrospectively analyzed, with 119(61.0%) having controlled disease and 76 (39.0%) having uncontrolled disease. The median time to diagnosis and disease course were 12 months and 28 months, respectively. A total of 358 pathogens have been reported with nontubercular mycobacterium (NTM) and Talaromyces marneffei as the most common pathogens. The recurrence rate was as high as 56.0%. The effective rates of antibiotics alone, antibiotics with rituximab, and antibiotics with cyclophosphamide were 40.5%, 73.5%, and 75%, respectively. In the multivariate logistic analysis, skin involvement, NTM infection, and recurrent infections remained significantly associated with disease control, with ORs of 3.25 (95% CI 1.187 ~ 8.909, P value = 0.022), 4.74 (95% CI 1.300 ~ 17.30, P value = 0.018), and 0.22 (95% CI 0.086 ~ 0.551, P value = 0.001), respectively. The patients with disease control had significant AIGA titer reduction. CONCLUSIONS: AIGA could cause severe opportunistic infections with unsatisfactory control, particularly in patients with recurrent infections. Efforts should be made to closely monitor the disease and regulate the immune system.

Subcutaneous Immunoglobulin 16.5% (Cutaquig®) in Primary Immunodeficiency Disease: Safety, Tolerability, Efficacy, and Patient Experience with Enhanced Infusion Regimens.

PURPOSE: To achieve reductions in infusion time, infusion sites, and frequency, a prospective, open-label, multicenter, Phase 3 study evaluated the safety, efficacy, and tolerability of subcutaneous immunoglobulin (SCIG) 16.5% (Cutaquig®, Octapharma) at enhanced infusion regimens. METHODS: Three separate cohorts received SCIG 16.5% evaluating volume, rate, and frequency: Cohort 1) volume assessment/site: up to a maximum 100 mL/site; Cohort 2) infusion flow rate/site: up to a maximum of 100 mL/hr/site or the maximum flow rate achievable by the tubing; Cohort 3) infusion frequency: every other week at twice the patient's weekly dose. RESULTS: For Cohort 1 (n = 15), the maximum realized volume per site was 108 mL/site, exceeding the currently labeled (US) maximum (up to 40 mL/site for adults). In Cohort 2 (n = 15), the maximum realized infusion flow rate was 67.5 mL/hr/site which is also higher than the labeled (US) maximum (up to 52 mL/hr/site). In Cohort 3 (n = 34), the mean total trough levels for every other week dosing demonstrated equivalency to weekly dosing (p value = 0.0017). All regimens were well tolerated. There were no serious bacterial infections (SBIs). Most patients had mild (23.4%) or moderate (56.3%) adverse events. The majority of patients found the new infusion regimens to be better or somewhat better than their previous regimens and reported that switching to SCIG 16.5% was easy. CONCLUSIONS: SCIG 16.5% (Cutaquig®), infusions are efficacious, safe, and well tolerated with reduced infusion time, fewer infusion sites, and reduced frequency. Further, the majority of patients found the new infusion regimens to be better or somewhat better than their previous regimens.

Quality of Life Evaluation in Saudi Arabian Pediatric Patients with Primary Immunodeficiency Diseases Receiving 20% Subcutaneous IgG Infusions at Home.

BACKGROUND AND AIMS: Subcutaneous immunoglobulin (SCIG) home infusion is widely used as an alternative to intravenous immunoglobulin (IVIG). This study aimed to determine the quality of life (QoL) of patients with primary immunodeficiency (PID) after switching to home-based SCIG. METHODS: In this prospective open-label single-center study, QoL was determined using the validated Arabic version of the Child Health Questionnaire at baseline and 3 and 6 months after switching from IVIG to SCIG. RESULTS: Twenty-four patients were recruited from July 2018 to August 2021, including 14 females and 10 males. The median age of the patients was 5 years (range, 0-14 years). The patients' diagnoses included severe combined immunodeficiency, combined immunodeficiency, agammaglobulinemia, Omenn syndrome, immunodysregulation, hyper-IgE syndrome, common variable immunodeficiency, and bare lymphocyte syndrome. The median duration on IVIG before inclusion was 40 months (range, 5-125 months). The QoL score showed a significant improvement in the patients' global health at 3 and 6 months compared with those at baseline and a significant improvement in the patients' general health at 3 and 6 months compared with that at baseline. The mean baseline serum IgG trough level was 8.8 ± 2.1 g/L. The mean serum IgG level was significantly higher on SCIG at both 3 and 6 months (11.7 ± 2.3 and 11.7 ± 2.5 g/L, respectively). CONCLUSIONS: This is the first study involving an Arab population to show improvement in the QoL of patients with PID after switching from hospital-based IVIG to home-based 20% SCIG.

Facilitated Subcutaneous Immunoglobulin Treatment in Patients with Immunodeficiencies: the FIGARO Study.

PURPOSE: The FIGARO study aims to provide insights on real-world utilization and tolerability of facilitated subcutaneous immunoglobulin (fSCIG) for primary immunodeficiency disease (PID) or secondary immunodeficiency disease (SID). METHODS: This prospective, multicenter, observational study, evaluated medical records, charts, and diaries of patients who had received at least 1 fSCIG infusion for PID or SID. Data were analyzed by cohort (PID, SID) and age groups (pediatric [< 18 years], adult [18-64 years], older adult [≥ 65 years]). Patients were followed up to 36 months. RESULTS: The study enrolled 156 patients: 15 pediatric, 120 adult, 21 older-adult. Twelve-month follow-up data were available for 128 patients. fSCIG was mainly prescribed for PID among patients aged < 65 years and for SID among older adults. At inclusion, 75.6% received their fSCIG infusion at home, and 78.7% self-administered. Adults were more likely to receive their initial infusion at home and self-administer (81.7% and 86.6%, respectively) than pediatric patients (53.3% each) and older adults (57.1% and 52.4%, respectively). At 12 months, the proportion of patients infusing at home and self-administering increased to 85.8% and 88.2%. Regardless of age, most patients self-administered the full fSCIG dose at home every 3-4 weeks and required a single infusion site. The tolerability profile was consistent with previous pivotal trials. Acute severe bacterial infections occurred in 0%-9.1% of patients during follow-up visits (full cohort). CONCLUSIONS: FIGARO confirms the feasibility, tolerability, and good infection control of fSCIG in PID and SID patients across the age spectrum in both the home-setting and medical facility. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov NCT03054181.

Use of immunoglobulin replacement therapy in patients with secondary antibody deficiency in daily practice: a European expert Q&A-based review.

INTRODUCTION: Secondary antibody deficiencies (SAD) are often a side effect of specific therapies that target B cells directly or affect the antibody response indirectly. Treatment of immunodeficiency by immunoglobulin replacement therapy (IgRT) is well established in primary antibody deficiencies, although the evidence for its use in SAD is less well established. To fill the gap and provide opinion and advice for daily practice, a group of experts met to discuss current issues and share best practical experience. AREAS COVERED: A total of 16 questions were considered that covered use of a tailored approach, definition of severe infections, measurement of IgG levels and specific antibodies, indications for IgRT, dosage, monitoring, discontinuation of IgRT, and Covid-19. EXPERT OPINION: Key points for better management SID should include characterization of the immunological deficiency, determination of the severity and degree of impairment of antibody production, distinguish between primary and secondary deficiency, and design a tailored treatment protocol that should include dose, route, and frequency of Ig replacement. There remains the need to carry out well-designed clinical studies to develop clear guidelines for the use of IgRT in patients with SAD.

A retrospective review of immunology patients with primary and/or secondary immunodeficiency, demonstrating the benefits of the rapid transitioning from intravenous immunoglobulin to subcutaneous immunoglobulin at the onset of the COVID-19 pandemic.

Forty-four of 50 immunology patients with primary or secondary immunodeficiency receiving intravenous immunoglobulin at a hospital in New South Wales, Australia, were rapidly enrolled in the subcutaneous immunoglobulin (SCIg) programme at the onset of the 2020 COVID-19 pandemic. Health and economic outcomes demonstrated that SCIg provides clinical efficacy as evidenced by the number of infections and maintenance of IgG levels, and also facilitates cost reduction in immunoglobulin maintenance programmes.

In-line warming reduces in-line pressure of subcutaneous infusion of concentrated immunoglobulins.

Immunoglobulin replacement therapy is a life-saving treatment in patients with immunodeficiency and effective in the management of autoimmune disorders. Immunoglobulins are administered intravenously or subcutaneously, with the latter route reducing systemic reactions and providing an option for self-infusion, increasing patient convenience, while decreasing patient burden, healthcare utilization, and costs. A major limitation with subcutaneous administrations is the frequency of infusion due to limited volumes administrable into subcutaneous space, necessitating increased drug concentration, absorption, and dispersion. Increasing the concentration of immunoglobulins from 10 to 20% halves the required volume, but leads to higher dynamic viscosity, limiting infusion rate. Recombinant human hyaluronidase increases dispersion and absorption of immunoglobulins allowing administration of ≤ 600 mL per site, but does not change viscosity. Since the viscosity of fluids depends on temperature, we tested the feasibility of in-line warming of immunoglobulin formulations to physiological temperatures. In vitro analysis showed no negative impact of in-line warming to 38 °C on product quality. Subcutaneous infusion studies in pigs confirmed the feasibility of infusion rates of up to 7.5 mL/min with in-line warmed TAK-881, an immunoglobulin 20% facilitated with recombinant human hyaluronidase. In-line pressures were reduced compared with conventional immunoglobulin 20%, and local tolerance was not altered. Reduction of in-line pressures was more pronounced with thinner needle sets, indicating a potential benefit for patients. In summary, an in in-line warming device can circumvent the limitation of high viscosity, while product quality and local tolerance are maintained. The results of the presented studies warrant further testing in a phase 1 clinical study.

Systemic Retinoids for Generalized Verrucosis Due to Congenital Immunodeficiency: Case Reports and Review of the Literature.

Generalized verrucosis (GV) is a group of immunodeficiency disorders accompanied by widespread human papillomavirus infection. We revisit two cases of GV due to congenital interleukin-7 deficiency successfully treated with systemic retinoids. We also present a review of the literature on the use of systemic retinoids to treat GV. Our review suggests that systemic retinoids are a safe and effective option for managing recalcitrant wart lesions in cases of GV.

Real-World Evidence of Tolerability of 20% Subcutaneous Immunoglobulin Treatment.

PURPOSE: The safety and efficacy of subcutaneous immune globulin 20% (human) solution (Ig20Gly) were demonstrated in clinical trials. However, real-world evidence of the tolerability of self-administered Ig20Gly in elderly patients is lacking. We describe real-world patterns of Ig20Gly usage for 12 months in patients with primary immunodeficiency diseases (PIDD) in the USA. METHODS: This retrospective chart review of longitudinal data from 2 centers included patients aged ≥ 2 years with PIDD. Ig20Gly administration parameters, tolerability, and usage patterns were assessed at initial and subsequent 6- and 12-month infusions. RESULTS: Of 47 enrolled patients, 30 (63.8%) received immunoglobulin replacement therapy (IGRT) within 12 months before starting Ig20Gly, and 17 (36.2%) started IGRT de novo. Patients were predominantly White (89.1%), female (85.1%), and elderly (aged > 65 years, 68.1%; median age = 71.0 years). Most adults received at-home treatment during the study, and most self-administered at 6 months (90.0%) and 12 months (88.2%). Across all time points, infusions were administered at a mean rate of 60-90 mL/h/infusion, using a mean of 2 sites per infusion, on a weekly or biweekly frequency. No emergency department visits occurred, and hospital visits were rare (n = 1). Forty-six adverse drug reactions occurred in 36.4% of adults, mostly localized site reactions; none of these or any adverse events led to treatment discontinuation. CONCLUSION: These findings demonstrate tolerability and successful self-administration of Ig20Gly in PIDD, including elderly patients and patients starting IGRT de novo.