Subcutaneous immunoglobulin for maintenance treatment in chronic inflammatory demyelinating polyneuropathy (PATH): a randomised, double-blind, placebo-controlled, phase 3 trial

Efficacy and Tolerability of Intravenous Immunoglobulin and Subcutaneous Immunoglobulin in Neurologic Diseases

PURPOSE

IV immunoglobulin (Ig) therapy has been widely used for the treatment of neurologic disorders, autoimmune diseases, immunodeficiency-related diseases, blood system diseases, and cancers. In this review, we summarize the efficacy and tolerability of IVIg and SCIg therapy in neurologic diseases.

METHODS

We summarized and analyzed the efficacy and tolerability of IVIg and SCIg in neurologic diseases, by analyzing the literature pertaining to the use of IVIg and SCIg to treat nervous system diseases.

FINDINGS

In clinical neurology practice, IVIg has been shown to be useful for the treatment of new-onset or recurrent immune diseases and for long-term maintenance treatment of chronic diseases. Moreover, IVIg may have applications in the management of intractable autoimmune epilepsy, paraneoplastic syndrome, autoimmune encephalitis, and neuromyelitis optica. SCIg is emerging as an alternative to IVIg treatment. Although SCIg has a composition similar to that of IVIg, the applications of this therapy are different. Notably, the bioavailability of SCIg is lower than that of IVIg, but the homeostasis level is more stable. Current studies have shown that these 2 therapies have pharmacodynamic equivalence.

IMPLICATIONS

In this review, we explored the efficacy of IVIg in the treatment of various neurologic disorders. IVIg administration still faces many challenges. Thus, it will be necessary to standardize the use of IVIg in the clinical setting. SCIg administration is a novel and feasible treatment option for neurologic and immune-related diseases, such as chronic inflammatory demyelinating polyradiculoneuropathy and idiopathic inflammatory myopathies. As our understanding of the mechanisms of action of IVIg improve, potential next-generation biologics can being developed.

Evaluation of a Personalized Subcutaneous Immunoglobulin Treatment Program for Neurological Patients

BACKGROUND

Subcutaneous immunoglobulin (SCIg) treatment has been shown to control symptoms and improve overall satisfaction in patients with neurological disorders. However, a large injection volume can be overwhelming and a barrier to successful SCIg treatment. We established a nurse-led individualized approach program to facilitate a smooth and successful treatment transition from intravenous immunoglobulin (IVIg) to SCIg. The program involved a lead nurse to provide two or more individual educational sessions on SCIg administration, establish a written transition plan, and liaise care with physicians.

OBJECTIVES

We aimed to evaluate the impact of our program to a successful transition defined as SCIg retention or adherence without a need to restart IVIg by six or twelve months.

METHODS

We reviewed medical charts of all patients with immune-mediated neuromuscular disorders who were in our program during January 2010 to Dec 2016.

RESULTS

Nineteen patients were identified. Mean IVIg treatment duration was 31.5 months (range 4-98) before the transition. Mean steady state SCIg dosage was 26.2 g/week (SD 10.3). All patients were initially able to switch to SCIg, with a retention rate of 17/19 (89.5%) at six months and 15/19 (78.9%) at twelve months. Two patients reverted back to IVIg treatment due to worsening of their symptoms at two and three months, while two required supplemental IVIg infusions. There were no major adverse events reported during the twelve-month period, but one minor cutaneous adverse event (redness around the injection site).

CONCLUSIONS

Successful treatment transition may be achieved with the nurse led individualized approach program.

Immune Globulin Subcutaneous (Human) 20% (Hizentra®): A Review in Chronic Inflammatory Demyelinating Polyneuropathy

Intravenous immunoglobulin (IVIg) is well-established in the treatment of patients with chronic inflammatory demyelinating polyneuropathy (CIDP). Immune globulin subcutaneous (human) 20% liquid (Hizentra^®; referred to as IgPro20 hereafter) has recently been approved in a number of countries, including the USA and those of the EU, as maintenance therapy in patients with CIDP. In the pivotal phase III PATH trial in adults with CIDP who were first stabilized on IVIg therapy, maintenance therapy with IgPro20 for 24 weeks significantly reduced CIDP relapse or study withdrawal rates versus placebo. Efficacy was sustained during ≤ 48 weeks of additional treatment with IgPro20 in the open-label PATH extension study. IgPro20 was generally well tolerated, with low rates of systemic adverse events (AEs); the most common AEs were local reactions (e.g. infusion-site erythema, infusion-site swelling). In PATH, more than one-half of IgPro20 recipients preferred this therapy to their previous IVIg therapy. IgPro20 offers a convenient alternative to IVIg with a better systemic AEs profile and thus extends the options for maintenance therapy in CIDP.

Clinical outcomes of polyvalent immunoglobulin use in solid organ transplant recipients: A systematic review and meta-analysis - Part II: Non-kidney transplant

Immunoglobulin (IG) is commonly used to desensitize and treat antibody-mediated rejection in solid organ transplant (SOT) recipients. The impact of IG on other outcomes such as infection, all-cause mortality, graft rejection, and graft loss is not clear. We conducted a similar systematic review and meta-analysis to our previously reported Part I excluding kidney transplant. A comprehensive literature review found 16 studies involving the following organ types: heart (6), lung (4), liver (4), and multiple organs (2). Meta-analysis could only be performed on mortality outcome in heart and lung studies due to inadequate data on other outcomes. There was a significant reduction in mortality (OR 0.34 [0.17-0.69]; 4 studies, n = 455) in heart transplant with hypogammaglobulinemia receiving IVIG vs no IVIG. Mortality in lung transplant recipients with hypogammaglobulinemia receiving IVIG was comparable to those of no hypogammaglobulinemia (OR 1.05 [0.49, 2.26]; 2 studies, n = 887). In summary, IVIG targeted prophylaxis may decrease mortality in heart transplant recipients as compared to those with hypogammaglobulinemia not receiving IVIG, or improve mortality to the equivalent level with those without hypogammaglobulinemia in lung transplant recipients, but there is a lack of data to support physicians in making decisions around using immunoglobulins in all SOT recipients for infection prophylaxis.

Immunoglobulin Treatment in Neuromuscular Medicine

Intravenous immunoglobulin (IVIg) is used in the treatment of autoimmune diseases, including immune-mediated central and peripheral nervous system disorders. This article will review the indications, proposed mechanism of actions, and administration of immunoglobulin treatment in various neuropathies, neuromuscular junction disorders, and myopathies. IVIg may have more than one mechanism of action to alter the pathogenesis of underlying neuromuscular disease. IVIg treatment has been used as a first-line treatment in Guillain-Barre syndrome, chronic inflammatory demyelinating polyradiculoneuropathy, multifocal motor neuropathy, and second-line off-label treatment in medically refractory cases of polymyositis, dermatomyositis, and myasthenia gravis. IVIg is a well-tolerated and effective treatment for these neuromuscular diseases. With this review article, we hope to increase clinicians' awareness of the indications and efficiencies of IVIg in a broad spectrum of neuromuscular diseases.

Ultrasound in Multifocal Motor Neuropathy: Clinical and Electrophysiological Correlations

OBJECTIVES

Multifocal motor neuropathy (MMN) is a treatable autoimmune polyneuropathy, which may prove challenging diagnostically in the setting of absent conduction blocks or advanced axonal loss. Relatively few studies have examined the role of ultrasound (US) in MMN.

METHODS

Retrospective, cross-sectional study of patients with MMN who underwent peripheral nerve US. Charts were reviewed to extract clinical, sonographic, and electrophysiological data.

RESULTS

Eleven patients with MMN underwent US between 2013 and 2015; of these 11 patients, 7 had ≥3 abnormal nerve segments, and 6 had ≥5 sites of increased cross-sectional area (CSA). There was moderate correlation between the degree of amplitude drop observed in the median and ulnar motor nerves, and CSA. Significant correlation between CSA and limb strength was only observed for the median nerve.

CONCLUSIONS

Peripheral nerve US shows promise as a diagnostic tool in MMN and may be helpful to distinguish MMN from motor neuron disease.

Retrospective correlation analysis of plasma Immunoglobulin G and clinical performance in CIDP

Background

Chronic inflammatory demyelinating polyneuropathy (CIDP) can be successfully treated with immunoglobulin either intravenously (IVIG) or subcutaneously (SCIG). Measurement of plasma immunoglobulin G levels (P-IgG) and its correlation to clinical improvement has shown conflicting results. This study aims to clarify whether changes in P-IgG are related to clinical development in patients with CIDP treated with IVIG or SCIG.

Methods

Patients from five previous studies treated with either IVIG or SCIG with evaluation at baseline and re-evaluation after two or 10/12 weeks, respectively were included. At evaluation and re-evaluation, the following tests were done: combined isokinetic muscle strength (cIKS), grip strength, 9-hole-peg test (9-HPT), 40-meter-walk test (40-MWT), clinical examination of muscle strength score by the Medical Research Council (MRC) and measurement of plasma immunoglobulin G (P-IgG).

Results

Fifty-five patients were included in the IVIG group and 41 in the SCIG group. There was no correlation between the changes in P-IgG and cIKS in neither the IVIG group (r = 0.137, p = 0.32) nor the SCIG group (r =  − 0.048, p = 0.77). Similarly, no correlations could be demonstrated between P-IgG and grip strength, 9-HPT, 40-MWT or MRC.

Conclusions

In patients with CIDP receiving SCIG or IVIG, changes in P-IgG during treatment did not correlate with changes in muscle strength or other motor performance skills.

Serum neurofilament light chain in chronic inflammatory demyelinating polyneuropathy

Axonal damage in chronic inflammatory demyelinating polyneuropathy (CIDP) is the main predictor of poor outcome. We hypothesized that serum neurofilament light chain (sNfL) reflects disease activity by detecting ongoing neuro-axonal damage in CIDP. Three prospective cohorts of CIDP patients were studied: (a) patients starting induction treatment (IT cohort, N = 29) measured at baseline and 6 months after starting treatment; (b) patients on maintenance treatment (MT) starting intravenous immunoglobuline (IVIg) withdrawal (MT cohort, N = 24) measured at baseline and 6 months after IVIg withdrawal or at time of relapse; and (c) patients in long-term remission without treatment (N = 27). A single molecule array assay was used to measure sNfL. Age-matched healthy controls (N = 30) and age-specific reference values were used for comparison. At baseline, sNfL was higher in patients starting IT compared to healthy controls. Ten out of 29 IT (34%) patients have sNfL levels above the 95th percentile of age-specific cut-off values. In the MT and remission cohort, elevated sNfL levels were infrequent and not different from healthy controls. sNfL levels were correlated with electrophysiological markers of axonal damage. At follow-up assessment, patients with active disease (non-responders and patients who relapsed after IVIg withdrawal) had higher sNfL levels compared with patients with stable disease (responders and patients who were successfully withdrawn from IVIg treatment). sNfL levels were increased in a third of CIDP patients starting IT and reflected axonal damage. sNfL levels might be usable as biomarker of disease activity in a subset of CIDP patients.

Restabilization treatment after intravenous immunoglobulin withdrawal in chronic inflammatory demyelinating polyneuropathy: Results from the pre-randomization phase of the Polyneuropathy And Treatment with Hizentra study

In patients with chronic inflammatory demyelinating polyneuropathy (CIDP), intravenous immunoglobulin (IVIG) is recommended to be periodically reduced to assess the need for ongoing therapy. However, little is known about the effectiveness of restabilization with IVIG in patients who worsen after IVIG withdrawal. In the Polyneuropathy And Treatment with Hizentra (PATH) study, the pre‐randomization period included sudden stopping of IVIG followed by 12 weeks of observation. Those deteriorating were then restabilized with IVIG. Of 245 subjects who stopped IVIG, 28 did not show signs of clinical deterioration within 12 weeks. Two hundred and seven received IVIG restabilization with an induction dose of 2 g/kg bodyweight (bw) IgPro10 (Privigen, CSL Behring, King of Prussia, Pennsylvania) and maintenance doses of 1 g/kg bw every 3 weeks for up to 13 weeks. Signs of clinical improvement were seen in almost all (n = 188; 91%) subjects. During IVIG restabilization, 35 subjects either did not show CIDP stability (n = 21, analyzed as n = 22 as an additional subject was randomized in error) or withdrew for other reasons (n = 14). Of the 22 subjects who did not achieve clinical stability, follow‐up information in 16 subjects after an additional 4 weeks was obtained. Nine subjects were reported to have improved, leaving a maximum of 27 subjects (13%) who either showed no signs of clinical improvement during the restabilization phase and 4 weeks post‐study or withdrew for other reasons. In conclusion, sudden IVIG withdrawal was effective in detecting ongoing immunoglobulin G dependency with a small risk for subjects not returning to their baseline 17 weeks after withdrawal.

Efficacy and safety of IVIG in CIDP: Combined data of the PRIMA and PATH studies

Intravenous immunoglobulin (IVIG) is a potential therapy for chronic inflammatory demyelinating polyneuropathy (CIDP). To investigate the efficacy and safety of the IVIG IgPro10 (Privigen) for treatment of CIDP, results from Privigen Impact on Mobility and Autonomy (PRIMA), a prospective, open‐label, single‐arm study of IVIG in immunoglobulin (Ig)‐naïve or IVIG pre‐treated subjects (NCT01184846, n = 28) and Polyneuropathy And Treatment with Hizentra (PATH), a double‐blind, randomized study including an open‐label, single‐arm IVIG phase in IVIG pre‐treated subjects (NCT01545076, IVIG restabilization phase n = 207) were analyzed separately and together (n = 235). Efficacy assessments included change in adjusted inflammatory neuropathy cause and treatment (INCAT) score, grip strength and Medical Research Council (MRC) sum score. Adverse drug reactions (ADRs) and ADRs/infusion were recorded. Adjusted INCAT response rate was 60.7% in all PRIMA subjects at Week 25 (76.9% in IVIG pre‐treated subjects) and 72.9% in PATH. In the pooled cohort (n = 235), INCAT response rate was 71.5%; median time to INCAT improvement was 4.3 weeks. No clear demographic differences were noticed between early (responding before Week 7, n = 148) and late responders (n = 21). In the pooled cohort, median change from baseline to last observation was −1.0 (interquartile range −2.0; 0.0) point for INCAT score; +8.0 (0.0; 20.0) kPa for maximum grip strength; +3.0 (1.0; 7.0) points for MRC sum score. In the pooled cohort, 271 ADRs were reported in 105 subjects (44.7%), a rate of 0.144 ADRs per infusion. This analysis confirms the efficacy and safety of IgPro10, a recently FDA‐approved IVIG for CIDP, in a population of mainly pre‐treated subjects with CIDP [Correction added on 14 March 2019 after first online publication: the INCAT response rate has been corrected.].

Measuring disease activity and predicting response to intravenous immunoglobulin in chronic inflammatory demyelinating polyneuropathy

Chronic inflammatory demyelinating polyneuropathy (CIDP) is characterised by significant clinical heterogeneity and as such reliable biomarkers are required to measure disease activity and assess treatment response. Recent advances in our understanding of disease pathogenesis and the discovery of novel serum-based, electrophysiologic and imaging biomarkers allow clinicians to make more informed decisions regarding individualised treatment regimes.

As a chronic immune-mediated process typified by relapse following withdrawal of immunomodulatory therapy, a substantial proportion of patients with CIDP require long term treatment with intravenous immunoglobulin (IVIg), a scarce and expensive donor-derived resource. The required duration and intensity of immunoglobulin treatment vary widely between individuals, highlighting both the heterogeneous nature of the underlying disease process as well as the variable pharmacologic properties of IVIg.

This review outlines the use of multimodal biomarkers in the longitudinal evaluation of nerve injury and how recent developments have impacted our ability to predict both response to immunoglobulin administration and its withdrawal.

Blood, blood components, plasma, and plasma products

This review of 2018 publications identifies side effects of blood, blood components, and plasma products. In addition, albumin, blood transfusion (erythrocytes, granulocytes, and platelets), blood substitutes (hemoglobin-based oxygen carriers), plasma products (alpha1-antitrypsin, C1 esterase inhibitor concentrate, cryoprecipitate, and fresh frozen plasma), plasma substitutes (etherified starches, and gelatin), globulins (intravenous immunoglobulin, subcutaneous immunoglobulin, and anti-D immunoglobulin), coagulation proteins (factor I, factor II, factor VIIa, factor VIII, factor IX, prothrombin complex concentrate, antithrombin III, and von Willebrand factor/factor VIII concentrates), erythropoietin and derivatives, thrombopoietin and receptor agonists, transmission of infectious agents through blood donation, and stem cells are reviewed. This chapter informs the reader about newly recognized and published data in the blood product domain.

Clinical and economic comparison of an individualised immunoglobulin protocol vs. standard dosing for chronic inflammatory demyelinating polyneuropathy

Background

The clinical and economic implications of an individualised intravenous immunoglobulin (IVIg) protocol for chronic inflammatory demyelinating polyneuropathy (CIDP) are unknown. Comparison with standard dosing regimens has not been performed.

Methods

We retrospectively studied 47 IVIg-treated subjects with CIDP over 4 years with an individualised, outcome-measured, dose-modifying protocol. We evaluated responder and remission rates, clinical improvement levels and dose requirements. We compared clinical benefits and costs with those reported with standard dosing at 1 g/kg every 3 weeks.

Results

The IVIg-responder rate was 83% and the 4-year remission rate was 25.6%. Mean IVIg dose requirements were 22.06 g/week (SD:15.29) in patients on ongoing therapy. Dose range was wide (5.83–80 g/week). Mean infusion frequency was every 4.34 weeks (SD:1.70) and infusion duration of 2.79 days (SD:1.15). Mean Overall Neuropathy Limitation Scale improvement was 2.54 (SD:1.89) and mean MRC sum score improvement of 12.23 (SD:7.17) in IVIg-responders. Mean modified-INCAT (Inflammatory Neuropathy Cause and Treatment) score improvement was similar (p = 0.47) and mean MRC sum score improvement greater (p < 0.001) in our cohort, compared to the IVIg-treated arm of the ICE Study. Mean drug costs were GBP 37,660/patient/year (€ 43,309) and mean infusion-related costs of GBP 17,115/patient/year (€ 19,682), totalling GBP 54,775/patient/year (€ 62,991). Compared to standard dosing using recorded weight, mean savings were of GBP 13,506/patient/year (€ 15,532). Compared to standard dosing using dosing weight, savings were of GBP 6,506/patient/year (€ 7,482).

Conclusion

Our results indicate that an individualised IVIg treatment protocol is clinically non-inferior and 10–25% more cost-effective than standard dosing regimens in CIDP.

IqYmune® is an effective maintenance treatment for multifocal motor neuropathy: A randomised, double-blind, multi-center cross-over non-inferiority study vs Kiovig®-The LIME Study

Intravenous immunoglobulin (IVIg) is the gold‐standard for maintenance treatment of multifocal motor neuropathy (MMN). This phase III, randomised, double‐blind, multi‐centre, active‐control, crossover study, aimed to evaluate the non‐inferiority of IqYmune® relative to Kiovig®, primarily based on efficacy criteria. Twenty‐two adult MMN patients, treated with any brand of IVIg (except Kiovig® or IqYmune®) at a stable maintenance dose within the range of 1 to 2 g/kg every 4 to 8 weeks, were randomised to receive either Kiovig® followed by IqYmune®, or IqYmune® followed by Kiovig®. Each product was administered for 24 weeks. The primary endpoint was the difference between IqYmune® and Kiovig® in mean assessments of modified Medical Research Council (MMRC) 10 sum score (strength of 5 upper‐limb and 5 lower‐limb muscle groups, on both sides, giving a score from 0 to 100) during the evaluation period (non‐inferiority margin of Δ = 2). A linear mixed model analysis demonstrated the non‐inferiority of IqYmune® relative to Kiovig®, independently of the covariates (value at baseline, treatment period, and treatment sequence). The estimated “IqYmune® − Kiovig®” difference was −0.01, with a 95% confidence interval (CI) −0.51 to 0.48. The number of adverse reactions (ARs) and the percentage of patients affected were similar for the two products: 39 ARs in 10 patients with IqYmune® vs 32 ARs in 11 patients with Kiovig®. No thromboembolic events nor haemolysis nor renal impairment were observed. In this first clinical trial comparing two IVIg brands for maintenance treatment of MMN, efficacy and tolerability of both brands were similar.

Immune-mediated neuropathies

Since the discovery of an acute monophasic paralysis, later coined Guillain-Barré syndrome, almost 100 years ago, and the discovery of chronic, steroid-responsive polyneuropathy 50 years ago, the spectrum of immune-mediated polyneuropathies has broadened, with various subtypes continuing to be identified, including chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) and multifocal motor neuropathy (MMN). In general, these disorders are speculated to be caused by autoimmunity to proteins located at the node of Ranvier or components of myelin of peripheral nerves, although disease-associated autoantibodies have not been identified for all disorders. Owing to the numerous subtypes of the immune-mediated neuropathies, making the right diagnosis in daily clinical practice is complicated. Moreover, treating these disorders, particularly their chronic variants, such as CIDP and MMN, poses a challenge. In general, management of these disorders includes immunotherapies, such as corticosteroids, intravenous immunoglobulin or plasma exchange. Improvements in clinical criteria and the emergence of more disease-specific immunotherapies should broaden the therapeutic options for these disabling diseases.

Immunoglobulin use in immune deficiency in the UK: a report of the UKPID and National Immunoglobulin Databases

Supply of immunoglobulin in the UK faces pressures due to increasing demand, cost and variable supply. This paper describes immunoglobulin replacement therapy (IGRT) in primary immunodeficiency (PID) and secondary immunodeficiency (SID) to assist in the ongoing planning of UK immunoglobulin provision. A retrospective analysis of the National Immunoglobulin Database and the UKPID registry was carried out. In total, 3,222 patients are registered as receiving IGRT for immunodeficiencies. Predominately antibody disorders made up the largest diagnostic category (61% of patients). The total cost of IGRT for immunodeficiency for 2015/16 was £40,673,350; an average annual cost of £1,099,254 per centre and £12,124 per PID patient. SCIg accounted for 43.8% and 50.1% of IGRT, with home therapy accounting for 42.7% and 57.5% of place of therapy in the National Immunoglobulin Database and UKPID registry respectively. In 2015/16 use of immunoglobulin in SID increased by 24% over the previous financial year. The overall trends of increasing demand in immunology are mirrored in other specialties, most notably neurology and haematology. These data are the first national overview of IGRT for immunodeficiencies, providing a valuable resource for clinicians and policy makers in the ongoing management of UK immunoglobulin supply.

IgPro20, the Polyneuropathy and Treatment with Hizentra® study (PATH), and the treatment of chronic inflammatory demyelinating polyradiculoneuropathy with subcutaneous IgG

Subcutaneous IgG (SCIG) administration may be preferred over the intravenous route (IVIG) in chronic inflammatory demyelinating polyneuropathy (CIDP) because it minimizes ‘end of cycle’ treatment-related fluctuations, reduces systemic adverse effects, improves convenience/quality of life and potentially lowers overall costs. Early reports of the use of highly concentrated SCIG preparations suggested they were effective and well-tolerated in chronic inflammatory demyelinating polyneuropathy. This was confirmed in the Polyneuropathy and Treatment with Hizentra® study of 172 subjects randomized to receive maintenance therapy with placebo or one of two doses of IgPro20 (20% IgG stabilized with L-Proline) for 6 months. Risk of relapse was reduced by SCIG in a dose-related manner as compared with placebo. A total of 88% of polyneuropathy and treatment with hizentra subjects felt the subcutaneous method was ‘easy to learn’. Local adverse events were mostly mild or moderate, and systemic adverse events were infrequent. Some patients may prefer maintenance therapy with SCIG over IVIG.

Adverse Effects of Immunoglobulin Therapy

Immunoglobulin has been widely used in a variety of diseases, including primary and secondary immunodeficiency diseases, neuromuscular diseases, and Kawasaki disease. Although a large number of clinical trials have demonstrated that immunoglobulin is effective and well tolerated, various adverse effects have been reported. The majority of these events, such as flushing, headache, malaise, fever, chills, fatigue and lethargy, are transient and mild. However, some rare side effects, including renal impairment, thrombosis, arrhythmia, aseptic meningitis, hemolytic anemia, and transfusion-related acute lung injury (TRALI), are serious. These adverse effects are associated with specific immunoglobulin preparations and individual differences. Performing an early assessment of risk factors, infusing at a slow rate, premedicating, and switching from intravenous immunoglobulin (IVIG) to subcutaneous immunoglobulin (SCIG) can minimize these adverse effects. Adverse effects are rarely disabling or fatal, treatment mainly involves supportive measures, and the majority of affected patients have a good prognosis.

History, Diagnosis, and Management of Chronic Inflammatory Demyelinating Polyradiculoneuropathy

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is probably the best recognized progressive immune-mediated peripheral neuropathy. It is characterized by a symmetrical, motor-predominant peripheral neuropathy that produces both distal and proximal weakness. Large-fiber abnormalities (weakness and ataxia) predominate, whereas small-fiber abnormalities (autonomic and pain) are less common. The pathophysiology of CIDP is inflammatory demyelination that manifests as slowed conduction velocities, temporal dispersion, and conduction block on nerve conduction studies and as segmental demyelination, onion-bulb formation, and endoneurial inflammatory infiltrates on nerve biopsies. Although spinal fluid protein levels are generally elevated, this finding is not specific for the diagnosis of ClDP. Other neuropathies can resemble CIDP, and it is important to identify these to ensure correct treatment of these various conditions. Consequently, metastatic bone surveys (for osteosclerotic myeloma), serum electrophoresis with immunofixation (for monoclonal gammopathies), and human immunodeficiency virus testing should be considered for testing in patients with suspected CIDP. Chronic inflammatory demyelinating polyradiculoneuropathy can present as various subtypes, the most common being the classical symmetrical polyradiculoneuropathy and the next most common being a localized asymmetrical form, multifocal CIDP. There are 3 well-established, first-line treatments of CIDP-corticosteroids, plasma exchange, and intravenous immunoglobulin-with most experts using intravenous immunoglobulin as first-line therapy. Newer immune-modulating drugs can be used in refractory cases. Treatment response in CIDP should be judged by objective measures (improvement in the neurological or electrophysiological examination), and treatment needs to be individualized to each patient.

Safety of Intravenous Immunoglobulin (Tegeline®), Administered at Home in Patients with Autoimmune Disease: Results of a French Study

The efficacy of intravenous immunoglobulins (IVIg) in patients with autoimmune diseases (AID) has been known for several decades. Majority of these patients received IVIg in hospital. A retrospective study was conducted in 22 centers in France to evaluate the feasibility of the administration of Tegeline, an IVIg from LFB Biomedicaments, and assess its safety at home, compared to in hospital, in patients with AID. The included patients were at least 18 years old, suffering from AID, and treated with at least 1 cycle of Tegeline at home after receiving 3 consecutive cycles of hospital-based treatment with Tegeline at a dose between 1 and 2 g/kg/cycle. Forty-six patients with AID, in most cases immune-mediated neuropathies, received a total of 138 cycles of Tegeline in hospital and then 323 at home. Forty-five drug-related adverse events occurred in 17 patients who received their cycles at home compared to 24 adverse events in hospital in 15 patients. Serious adverse events occurred in 3 patients during home treatment, but they were not life-threatening and did not lead to discontinuation of Tegeline. Forty-five patients continued their treatment with Tegeline at home or in hospital; 39 (84.8%) were still receiving home treatment at the end of the study. In conclusion, the study demonstrates the good safety profile of Tegeline administered at home at high doses in patients with AID who are eligible for home administration of Tegeline.

A randomised, multi-centre phase III study of 3 different doses of intravenous immunoglobulin 10% in patients with chronic inflammatory demyelinating polyradiculoneuropathy (ProCID trial): Study design and protocol

Patients with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) show varying degrees of response to intravenous immunoglobulin (IVIg) therapy. This randomised phase III study in patients with CIDP (ProCID trial) will compare the efficacy and safety of 3 different doses (0.5, 1.0, and 2.0 g/kg) of IVIg 10% (panzyga) administered every 3 weeks for 24 weeks. The primary efficacy endpoint is the rate of treatment response, defined as a decrease in adjusted inflammatory neuropathy cause and treatment disability score of ≥1 point, in the IVIg 1.0 g/kg arm at week 24. Patients with definite or probable CIDP according to European Federation of Neurological Sciences/Peripheral Nerve Society criteria with IVIg or corticosteroid dependency and active disease are eligible. All potentially eligible patients will undergo IVIg or corticosteroid dose reduction (washout phase) over ≤12 weeks or until deterioration of CIDP (active disease). Patients with deterioration during the washout phase will be randomised to receive study treatment during a dose‐evaluation phase starting with a loading dose of IVIg 2.0 g/kg followed by maintenance treatment with IVIg 0.5, 1.0, or 2.0 g/kg every 3 weeks. Rescue medication (2 doses of IVIg 2.0 g/kg given 3 weeks apart) will be administered to patients in the IVIg 0.5 and 1.0 g/kg groups who deteriorate after week 3 and before week 18 or who do not improve at week 6. Safety, tolerability and quality of life will be assessed. The ProCID study will provide new information on the best maintenance dose of IVIg for patients with CIDP.

Individualized immunoglobulin therapy in chronic immune-mediated peripheral neuropathies

Despite the well-recognized importance of immunoglobulin therapy individualization during the treatment of chronic inflammatory demyelinating polyneuropathy (CIDP), the pathway to best achieve optimization is unknown. There are many pharmacokinetic and immunobiologic variables that can potentially influence the appropriateness of any individual therapy. Although identification of specific autoantibodies and their targets has only been accomplished in a minority of patients with CIDP, already the diagnostic and treatment implications of specific autoantibody detection are being realized. Individual variability in IgG pharmacokinetic properties including IgG catabolic rates and distribution, as well as the IgG level necessary for disease control also require consideration during the optimization process. For optimization to be successful there must be a measure of treatment response that has a clinically meaningful interpretation. There are currently available well-defined and validated clinical assessment tools and outcome measures that are well suited for this purpose. While there remains much to learn on how best to manipulate immunopathology and immunoglobulin pharmacokinetics in the most favorable way, there currently exists an understanding of these principles to a degree sufficient to begin to develop rational and evidence-based treatment optimization strategies.

Fingolimod therapy is not effective in a mouse model of spontaneous autoimmune peripheral polyneuropathy

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is an autoimmune disorder, which causes progressive sensory and motor deficits and often results in severe disability. Knockout of the co-stimulatory protein CD86 in mice of the non-obese diabetic background (NoD.129S4-Cd86^tm1Shr/JbsJ) results in the development of a spontaneous autoimmune peripheral polyneuropathy (SAPP). We used this previously described transgenic model to study the effects of the sphingosine-1-phosphate receptor agonist fingolimod on SAPP symptoms, functional and electrophysiological characteristics. Compared to two control strains, knockout of CD86 in NOD mice (CD86^−/− NOD) resulted in progressive paralysis with distinct locomotor deficits due to a severe sensory-motor axonal-demyelinating polyneuropathy as assessed by electrophysiological measurements. We started fingolimod treatment when CD86^−/− NOD mice showed signs of unilateral hind limb weakness and continued at a dose of 1 mg/kg/day for eight weeks. We did not observe any beneficial effects of fingolimod regarding disease progression. In addition, fingolimod did not influence the functional outcome of CD86^−/− NOD mice compared to vehicle treatment nor any of the electrophysiological characteristics. In summary, we show that fingolimod treatment has no beneficial effects in autoimmune polyneuropathy, which is in line with recent clinical data obtained in CIDP patients.