Subcutaneous immunoglobulin in CIDP and MMN: a short-term nationwide study

[Prospect of novel therapies in immune-mediated neuropathies]

The efficacy of immunotherapies such as steroids, plasmapheresis, and intravenous immunoglobulin have been proven in various immune-mediated neuropathies. However, these treatments sometimes lack the efficacy in a part of patients with the immune-mediated neuropathies. In addition, anti-myelin associated glycoprotein (MAG) neuropathy is usually refractory to the treatments. Recently, novel therapies targeting a molecule which are associated with pathogenesis of immune-mediated diseases, have been developed. These molecularly targeted therapies are notable in immune-mediated neuropathies as novel drug candidates. In the present article, current treatments and future prospect of novel therapies in immune-mediated neuropathies will be reviewed.

Subcutaneous Immunoglobulin in Chronic Inflammatory Demyelinating Polyneuropathy: A Historical Perspective

The therapeutic administration of subcutaneous immunoglobulin (SCIg) offers various advantages over intravenous immunoglobulin (IVIg). This narrative review examines and compares SCIg versus IVIg in chronic inflammatory demyelinating polyneuropathy (CIDP). SCIg is as effective as IVIg but is better tolerated and easier to administer, as intravenous access is not required. Furthermore, SCIg administration is more convenient and cost-effective than IVIg, enabling flexible treatment scheduling at home and improving patients' overall quality of life. The availability of highly concentrated immunoglobulin G (IgG) subcutaneous solutions, such as IgPro20, a 20% IgG solution stabilized with L-proline, allows for the administration of larger volumes in a single session, while the parallel development of new technological devices enables the delivery of higher doses over a shorter time. Based on the results of the PATH study, SCIg has become a well-established therapy in CIDP. In addition to discussing the advantages of SCIg, this review summarizes the evolution of SCIg by discussing all the relevant clinical studies which have considered its use in the treatment of CIDP.

Standardized Tapering off Subcutaneous Immunoglobulin in Chronic Inflammatory Demyelinating Polyneuropathy

BACKGROUND

Attempting discontinuation of treatment in patients with chronic inflammatory demyelinating polyneuropathy (CIDP) is recommended. However, there is no evidence based regimen for tapering off subcutaneous immunoglobulin (SCIG). This trial investigated stepwise tapering off SCIG to detect remission and the lowest effective dosage. During tapering off, frequent vs less frequent clinical evaluation was compared.

METHODS

Patients with CIDP receiving a stable SCIG dosage followed a standardized tapering off regimen: 90%, 75%, 50%, 25% and 0% of the initial dose every 12th week, pending no deterioration occurred. In case of relapse during tapering off, the lowest effective dose was identified. Treatment with SCIG was registered for two years after participation. Disability score and grip strength were primary parameters. Participants were randomized to clinical evaluation every 6th week (frequent) or 12th week (less frequent).

RESULTS

Fifty-five patients were included of which thirty-five relapsed. Twenty patients (36%) were able to discontinue treatment without relapse. In relapsing patients, median dosage could be reduced by 10% (range, 0-75). After two years, 18 of 20 patients were still in remission without treatment. Frequent clinical evaluation did not detect deterioration more frequently than less frequent evaluation; RR 0.5 (95% CI, 0.2-1.2) (p = 0.17).

CONCLUSION

In stable CIDP patients, SCIG could be completely tapered off in 36% of the patients and only in 10% of these patients relapse occurred during the following two years. More frequent evaluation was not superior to detect deterioration.

Update on therapy of chronic immune-mediated neuropathies

Chronic immune-mediated neuropathies, including chronic inflammatory demyelinating polyradiculoneuropathy (CIDP), neuropathies associated with monoclonal gammopathy, and multifocal motor neuropathy (MMN), are a group of disorders deemed to be caused by an immune response against peripheral nerve antigens. Several immune therapies have been reported to be variably effective in these neuropathies including steroids, plasma exchange, and high-dose intravenous (IVIg) or subcutaneous (SCIg) immunoglobulins. These therapies are however far from being invariably effective and may be associated with a number of side effects leading to the use of immunosuppressive agents whose efficacy has not been so far confirmed in randomized trials. More recently, new biological agents, such as rituximab, have proved to be effective in patients with neuropathy associated with IgM monoclonal gammopathy and are currently tested in CIDP.

Immunoglobulin for multifocal motor neuropathy

BACKGROUND

Multifocal motor neuropathy (MMN) is a rare, probably immune-mediated disorder characterised by slowly progressive, asymmetric, distal weakness of one or more limbs with no objective loss of sensation. It may cause prolonged periods of disability. Treatment options for MMN are few. People with MMN do not usually respond to steroids or plasma exchange. Uncontrolled studies have suggested a beneficial effect of intravenous immunoglobulin (IVIg). This is an update of a Cochrane Review first published in 2005, with an amendment in 2007. We updated the review to incorporate new evidence.

OBJECTIVES

To assess the efficacy and safety of intravenous and subcutaneous immunoglobulin in people with MMN.

SEARCH METHODS

We searched the following databases on 20 April 2021: the Cochrane Neuromuscular Specialised Register, CENTRAL, MEDLINE, Embase, ClinicalTrials.gov, and WHO ICTRP for randomised controlled trials (RCTs) and quasi-RCTs, and checked the reference lists of included studies.

SELECTION CRITERIA

We considered RCTs and quasi-RCTs examining the effects of any dose of IVIg and subcutaneous immunoglobulin (SCIg) in people with definite or probable MMN for inclusion in the review. Eligible studies had to have measured at least one of the following outcomes: disability, muscle strength, or electrophysiological conduction block. We used studies that reported the frequency of adverse effects to assess safety.

DATA COLLECTION AND ANALYSIS

Two review authors independently reviewed the literature searches to identify potentially relevant trials, assessed risk of bias of included studies, and extracted data. We followed standard Cochrane methodology.

MAIN RESULTS

Six cross-over RCTs including a total of 90 participants were suitable for inclusion in the review. Five RCTs compared IVIg to placebo, and one compared IVIg to SCIg. Four of the trials comparing IVIg versus placebo involved IVIg-naive participants (induction treatment). In the other two trials, participants were known IVIg responders receiving maintencance IVIg at baseline and were then randomised to maintenance treatment with IVIg or placebo in one trial, and IVIg or SCIg in the other. Risk of bias was variable in the included studies, with three studies at high risk of bias in at least one risk of bias domain. IVIg versus placebo (induction treatment): three RCTs including IVIg-naive participants reported a disability measure. Disability improved in seven out of 18 (39%) participants after IVIg treatment and in two out of 18 (11%) participants after placebo (risk ratio (RR) 3.00, 95% confidence interval (CI) 0.89 to 10.12; 3 RCTs, 18 participants; low-certainty evidence). The proportion of participants with an improvement in disability at 12 months was not reported. Strength improved in 21 out of 27 (78%) IVIg-naive participants treated with IVIg and one out of 27 (4%) participants who received placebo (RR 11.00, 95% CI 2.86 to 42.25; 3 RCTs, 27 participants; low-certainty evidence). IVIg treatment may increase the proportion of people with resolution of at least one conduction block; however, the results were also consistent with no effect (RR 7.00, 95% CI 0.95 to 51.70; 4 RCTs, 28 participants; low-certainty evidence). IVIg versus placebo (maintenance treatment): a trial that included participants on maintenance IVIg treatment reported an increase in disability in 17 out of 42 (40%) people switching to placebo and seven out of 42 (17%) remaining on IVIg (RR 2.43, 95% CI 1.13 to 5.24; 1 RCT, 42 participants; moderate-certainty evidence) and a decrease in grip strength in 20 out of 42 (48%) participants after a switch to placebo treatment compared to four out of 42 (10%) remaining on IVIg (RR 0.20, 95% CI 0.07 to 0.54; 1 RCT, 42 participants; moderate-certainty evidence). Adverse events, IVIg versus placebo (induction or maintenance): four trials comparing IVIg and placebo reported adverse events, of which data from two studies could be meta-analysed. Transient side effects were reported in 71% of IVIg-treated participants versus 4.8% of placebo-treated participants in these studies. The pooled RR for the development of side effects was 10.33 (95% CI 2.15 to 49.77; 2 RCTs, 21 participants; very low-certainty evidence). There was only one serious side effect (pulmonary embolism) during IVIg treatment. IVIg versus SCIg (maintenance treatment): the trial that compared continuation of IVIg maintenance versus SCIg maintenance did not measure disability. The evidence was very uncertain for muscle strength (standardised mean difference 0.08, 95% CI -0.84 to 1.00; 1 RCT, 9 participants; very low-certainty evidence). The evidence was very uncertain for the number of people with side effects attributable to treatment (RR 0.50, 95% CI 0.18 to 1.40; 1 RCT, 9 participants; very low-certainty evidence).

AUTHORS' CONCLUSIONS

Low-certainty evidence from three small RCTs shows that IVIg may improve muscle strength in people with MMN, and low-certainty evidence indicates that it may improve disability; the estimate of the magnitude of improvement of disability has wide CIs and needs further studies to secure its significance. Based on moderate-certainty evidence, it is probable that most IVIg responders deteriorate in disability and muscle strength after IVIg withdrawal. SCIg might be an alternative treatment to IVIg, but the evidence is very uncertain. More research is needed to identify people in whom IVIg withdrawal is possible and to confirm efficacy of SCIg as an alternative maintenance treatment.

Subcutaneous immunoglobulin treatment for chronic inflammatory demyelinating polyneuropathy

Immunoglobulin G (IgG) therapy is an established long‐term treatment in chronic inflammatory demyelinating polyneuropathy (CIDP) that is commonly administered intravenously (IVIg). The subcutaneous immunoglobulin (SCIg) administration route is a safe and effective alternative option, approved by the United States Food and Drug Administration (FDA) in 2018, for maintenance treatment of adults with CIDP. Physicians and patients alike need to be aware of all their treatment options in order to make informed decisions and plan long‐term treatment strategies. In this review, we collate the evidence for SCIg in CIDP from all published studies and discuss their implications and translation to clinical practice. We also provide guidance on the practicalities of how and when to transition patients from IVIg to SCIg and ongoing patient support. Evidence suggests that IVIg and SCIg have comparable long‐term efficacy in CIDP. However, SCIg can provide additional benefits for some patients, including no requirement for venous access or premedication, and reduced frequency of systemic adverse events. Local‐site reactions are more common with SCIg than IVIg, but these are mostly well‐tolerated and abate with subsequent infusions. Data suggest that many patients prefer SCIg following transition from IVIg. SCIg preference may be a result of the independence and flexibility associated with self‐infusion, whereas IVIg preference may be a result of familiarity and reliance on a healthcare professional for infusions. In practice, individualizing maintenance dosing based on disease behavior and determining the minimally effective IgG dose for individuals are key considerations irrespective of the administration route chosen.

Impact of subcutaneous immunoglobulin on quality of life in patients with chronic inflammatory demyelinating polyneuropathy previously treated with intravenous immunoglobulin

INTRODUCTION/AIMS

Intravenous immunoglobulin (IVIg) is a common therapy for patients with chronic inflammatory demyelinating polyneuropathy (CIDP). IVIg may cause systemic adverse events (AEs); therefore, infusion of subcutaneous immunoglobulin (SCIg) may be preferred by some patients. In this study we document the experiences of patients transitioning from IVIg to SCIg.

METHODS

Transitioning subjects with CIDP were followed in a 6-month prospective, open-label study. The primary endpoint was percentage of subjects who withdrew for any reason (including significant AEs). The secondary endpoint was symptom progression or relapse requiring a change in management. Quality of life (QOL) and treatment satisfaction were assessed using the Short Form 36-item Health Survey (SF-36), Treatment Satisfaction Questionnaire for Medication (TSQM), and Chronic Acquired Polyneuropathy Patient-Reported Index (CAP-PRI). Efficacy was assessed using the Inflammatory Rasch-built Overall Disability Scale, hand-held dynamometry, limb motor strength testing (LMST), and timed 25-ft walk (T25-FW).

RESULTS

Fifteen CIDP subjects transitioned from IVIg to SCIg. Of these, three (20%) met the primary endpoint and one (7%) met the secondary endpoint. The SF-36 showed a statistically significant improvement for the domain of role limitations-physical after 24 weeks (P = .03), with no significant differences observed in other domains. TSQM and CAP-PRI showed significant differences in favor of SCIg (P = .003 and .02, respectively). No significant differences were observed in efficacy after 24 weeks, except for LMST, which favored SCIg (P = .003). Eight of the 12 study completers (67%) continued with SCIg.

DISCUSSION

Transition to SCIg was associated with maintained efficacy and improved QOL.

Long-term treatment with subcutaneous immunoglobulin in multifocal motor neuropathy

Multifocal motor neuropathy (MMN) is a rare disease with a prevalence of less than 1 per 100,000 people. Intravenous immunoglobulin (IVIG) therapy, performed for a long-term period, has been demonstrated able to improve the clinical picture of MMN patients, ameliorating motor symptoms and/or preventing disease progression. Treatment with subcutaneous immunoglobulin (SCIg) has been shown to be as effective as IVIG. However, previously published data showed that follow-up of MMN patients in treatment with SCIg lasted no more than 56 months. We report herein the results of a long-term SCIg treatment follow up (up to 96 months) in a group of 8 MMN patients (6 M; 2F), previously stabilized with IVIG therapy. Clinical follow-up included the administration of Medical Research Council (MRC) sum-score, the Overall Neuropathy Limitation Scale (ONLS) and the Life Quality Index questionnaire (LQI) at baseline and then every 6 months. Once converted to SCIg, patients’ responsiveness was quite good. Strength and motor functions remained stable or even improved during this long-term follow-up with benefits on walking capability, resistance to physical efforts and ability in hand fine movements.

Switch from intravenous to subcutaneous immunoglobulin IgPro20 in CIDP patients: a prospective observational study under real-world conditions

Background:

IgPro20 is the first approved subcutaneous immunoglobulin (SCIg) preparation for the treatment of patients with chronic inflammatory demyelinating polyneuropathy (CIDP). Two different doses of the SCIg preparation were investigated in the pivotal PATH study. Real-world data, and particularly the efficacy of an equivalent dose switch from intravenous immunoglobulin (IVIg) to SCIg, are still not available.

Methods:

In this prospective observational study, 41 patients with CIDP treated with intravenous immunoglobulin (IVIg) were changed to an equivalent (1:1) dose of IgPro20 1 week after last IVIg treatment. Patients were examined at the time of switch from IVIg to SCIg, after 3 and after 6 months and efficacy, treatment preferences and systemic and local reactions were assessed.

Results:

Various clinical outcome parameters demonstrated overall stability regarding disability, general activity and social participation, grip and muscle strength, as well as gait impairment. Treatment satisfaction remained unchanged between IVIg and SCIg therapy. However, 88% of patients favoured treatment with subcutaneous IgPro20 over IVIg 6 months after switch to IgPro20.

Conclusion:

Results demonstrate that the switch of IVIg to an equivalent dose of SCIg represents an effective and preferred treatment option for CIDP patients.

Subcutaneous immunoglobulin dose titration to clinical response in inflammatory neuropathy

INTRODUCTION

Individualized dosing is an established approach in intravenous immunoglobulin (IVIg) treatment for inflammatory neuropathies. There is less experience in effective dosing strategies for subcutaneous (SC) immunoglobulin.

METHODS

We conducted a retrospective cohort study of patients with inflammatory neuropathies transferring from IVIg to SCIg in two UK peripheral nerve services. I-RODS and grip strength were used to measure outcome. Dose and clinical progress were documented at 1 year and at last review.

RESULTS

44/56 patients remained on maintenance SCIg beyond 1 year (mean 3.3 years, range 1-9 years) with stable clinical outcomes. Clinical deteriorations were corrected by small increases in SCIg dose in 20 patients at 1 year, a further 9 requiring subsequent further up-titrations. Sixteen tolerated dose reduction. Mean dose change was + 2.4% from baseline. Two patients required IVIg bolus rescue (2 g/kg). Three patients successfully discontinued Ig therapy. Nine patients returned to IVIg due to clinical relapse or patient preference. Overall tolerance was good.

DISCUSSION

Dose titration to clinical response is an effective approach in SCIg maintenance therapy.

Reassessing IVIg therapy in chronic inflammatory demyelinating polyradiculoneuropathy during COVID-19: a chance to verify the need for chronic maintenance therapy

The outbreak of a severe acute respiratory syndrome caused by a novel coronavirus (COVID-19), has raised health concerns for patients with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP), who are frequently on long-term immunotherapies. Treatment with IVIg does not increase the risk of contracting COVID-19, and the IVIg administration may have a protective role. However, infusions can expose patients to an increased risk of contracting SARS-CoV-2 due to repeated access to Health Facilities. In this report we analyzed the short-term follow-up of CIDP patients who modified their chronic IVIg therapy during pandemic. About half of CIDP patients regularly treated with IVIg tried to stop treatment and about 10% shifted to SCIg. Forty-two percent of the patients who stopped the treatment reported a clinical deterioration after suspension and had to restart IVIg. This study demonstrated that in selected cases it is possible to successfully stop the chronic IVIg treatment, even in patients who have been treated for several years.

Quality of life in chronic inflammatory demyelinating polyneuropathy patients treated with subcutaneous immunoglobulin

BACKGROUND

Subcutaneous immunoglobulin (SCIG) is effective treatment of chronic inflammatory demyelinating polyneuropathy (CIDP). Quality of life (QoL) increases following switch from intravenous administration to SCIG, but its correlation with clinical functioning is sparsely studied.

AIMS OF THE STUDY

The aim of this study is to evaluate the correlation between QoL and clinical functioning in CIDP patients treated with SCIG.

METHODS

Danish patients with CIDP with a disease duration <10 years and currently treated with SCIG were eligible for inclusion. QoL was assessed with EQ-5D-5L and disability by the Overall Disability Sum Score (ODSS) and Rasch-built Overall Disability Scale (RODS). Gait performance was evaluated by a 40-meter-walk test (40-MWT) and a 6-spot-step test (6-SST) along with assessment of muscle strength (Medical Research Council score [MRC]). Correlations between QoL and the measured scores were calculated.

RESULTS

Of 92 eligible patients, 44 were included. QoL on the visual analogue scale (VAS) was 65% (range: 15-90) of the level of healthy controls (P = .03) and correlated to impaired gait function by 40-MWT and 6-SST. QoL correlated to RODS and ODSS, whereas there was no correlation with the MRC score.

CONCLUSIONS

In SCIG treated CIDP patients QoL is reduced and correlates to gait performance and disability.

Expanding the Role of the Pharmacist: Immunoglobulin Therapy and Disease Management in Neuromuscular Disorders

Immunoglobulin G (IgG) is a commonly used treatment for chronic neuromuscular disorders (NMDs), such as chronic inflammatory demyelinating polyneuropathy and multifocal motor neuropathy. IgG therapy has also shown promise in treating other NMDs including myasthenia gravis, polymyositis, and dermatomyositis. IgG is administered as either intravenous immunoglobulin (IVIg) or subcutaneous immunoglobulin (SCIg), with SCIg use becoming more popular due to the treatment burden associated with IVIg. IVIg requires regular venous access; long infusions (typically 4-6 hours); and can result in systemic adverse events (AEs) for some patients. In contrast, SCIg can be self-administered at home with shorter infusions (approximately 1 hour) and fewer systemic AEs. As patient care shifts toward home-based settings, the role of the pharmacist is paramount in providing a continuation of care and acting as the bridge between patient and clinic. Pharmacists with a good understanding of current recommendations, dosing strategies, and administration routes for IgG therapy are best placed to support patients. The aims of this review are to highlight the evidence supporting IgG therapy in the treatment of NMDs and provide practical information on patient management and IVIg/SCIg dosing in order to guide pharmacists on optimizing clinical outcomes and patient care.

Long-term treatment with subcutaneous immunoglobulin in patients with chronic inflammatory demyelinating polyradiculoneuropathy: a follow-up period up to 7 years

Chronic Inflammatory Demyelinating Polyneuropathy (CIDP) is a rare and heterogeneous acquired sensory-motor polyneuropathy with autoimmune pathogenesis. Intravenous immunoglobulins (IVIG) are a well-established therapy for CIDP: it is well known that at least two-thirds of these patients need these infusions for several years. More recently, Subcutaneous Immunoglobulins (SCIg) have been proved to be effective: this finding has been confirmed either in isolated cases or in few randomized trials. However, it appeared that the longest SCIg treatment follow up lasted no longer than 48 months. We report herein the results of a long-term SCIg treatment with a follow up period up to 7 years (84 months), considering safety, tolerability and patients’ perception of SCIg treatment in a CIDP population. We studied 17 patients (10 M; 7 F) with a diagnosis of CIDP, defined according to the EFNS/PNS criteria, successfully treated with IVIG every 4/6 weeks before being switched to SCIg treatment. Clinical follow-up included, apart from a routinely clinical assessment, the administration of Medical Research Council (MRC) sum-score, the Overall Neuropathy Limitation Scale (ONLS) and the Life Quality Index questionnaire (LQI). The results showed that, in the majority of this pre-selected group of CIDP patients (16/17), SCIg were well tolerated and were preferred over IVIG. Strength and motor functions remained stable or even improved during the long term follow-up (up to 84 months) with benefits on walking capability and resistance, manual activity performances and fatigue reduction.

Evaluation of Quality of Life in Patients With Chronic Inflammatory Demyelinating Polyneuropathy in Iran

OBJECTIVES

In addition to the physical disability in chronic inflammatory demyelinating polyneuropathy (CIDP), various aspects of quality of life (QoL) are affected by the disease. Our goal was to evaluate the QoL in Iranian patients with CIDP and to study the association of clinical and demographic factors with QoL parameters.

METHODS

Twenty-six Iranian patients with CIDP were asked to complete a standardized Persian version of SF-36, and the association of demographic and functional parameters with QoL parameters was assessed.

RESULTS

Sex, living place, and income had no significant effect on QoL. Mean physical composite score was 37.7 ± 9.4, and mean mental composite score was 37.2 ± 15.2 that was lower than similar studies. There was a positive correlation between QoL and muscle strength of different muscle groups [hand (r = 0.41, P = 0.04); hip (r = 0.44, P = 0.02); and foot (r = 0.41, P = 0.04); total manual muscle testing (r = 0.46, P = 0.02)] and a significant negative correlation between the duration of illness and mean physical composite score (r = -0.61, P = 0.00).

CONCLUSIONS

Our patients achieved low scores in both the physical and mental aspects of QoL compared with other studies. We found a significant correlation between the physical domain of the SF-36 score and muscle strength of the hand, hip, and foot muscle group and with total manual muscle testing, suggesting that physical disability is the most crucial factor affecting QoL. Also, there was a significant negative association between the duration of the disease and the physical domain.

Immunosuppressive and immunomodulatory therapies for neuromuscular diseases. Part II: New and novel agents

While traditional immunosuppressive and immunomodulatory therapies remain the cornerstone of immune-mediated neuromuscular disease management, new and novel agents including antigen-specific, monoclonal antibody drugs, have emerged as important treatment options. This article is the second of a two-part series that reviews immune-based therapies in neuromuscular diseases. The first article provides an update on the use of traditional immune-based therapies such as corticosteroids, plasma exchange, steroid-sparing immunosuppressive drugs, and intravenous immunoglobulin G. This second article focuses on new and novel immune-based therapies, including eculizumab, a complement inhibitor approved for acetylcholine receptor antibody-positive myasthenia gravis; rituximab, a B-cell depletion therapy with evolving indications in neuromuscular diseases; and the subcutaneous formulation of immunoglobulin G that gained approval for use in chronic inflammatory demyelinating polyradiculoneuropathy in 2018. Finally, several novel antigen-specific drugs at different stages of investigation in neuromuscular disease are also reviewed.

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.

Human immune globulin 10% with recombinant human hyaluronidase in multifocal motor neuropathy

Objective

The primary aim was to determine the safety of treatment with human immune globulin 10% with recombinant human hyaluronidase (fSCIg) compared to intravenous immunoglobulin (IVIg) in a prospective open-label study in patients with multifocal motor neuropathy (MMN).

Methods

Our study consisted of two phases: the IVIg phase (visits 1–3; 12 weeks), in which patients remained on IVIg treatment, and the fSCIg phase (visits 4–7; 36 weeks), in which patients received fSCIg treatment. After visit 3, IVIg was switched to an equivalent dose and frequency of fSCIg. Outcome measures were safety, muscle strength, disability and treatment satisfaction.

Results

Eighteen patients were enrolled in this study. Switching to fSCIg reduced the number of systemic adverse events (IVIg 11.6 vs. fSCIg 5.0 adverse events/per person-year, p < 0.02), and increased the number of local reactions at the injection site (IVIg 0 vs. fSCIg 3.3 local reactions/per person-year, p < 0.01). Overall, no significant differences in muscle strength and disability between fSCIg and IVIg were found. Treatment with fSCIg was perceived as optimal treatment option by 8 of the 17 patients (47.1%) and they continued with fSCIg after study closure because of improved independence and flexibility to administer treatment.

Conclusion

Treatment with fSCIg can be considered a safe alternative for patients with MMN on IVIg treatment. fSCIg could be a favorable option in patients who prefer self-treatment and more independency, and in patients who experience systemic adverse events on IVIg or have difficult intravenous access.

Electronic supplementary material

The online version of this article (10.1007/s00415-019-09475-x) contains supplementary material, which is available to authorized users.

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.

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.

Efficacy and patient satisfaction in the use of subcutaneous immunoglobulin immunotherapy for the treatment of auto-immune neuromuscular diseases

We reviewed the efficacy of SCIg administration in terms of muscle strength maintenance and patient satisfaction comparing with IVIg in the treatment of auto-immune neuromuscular diseases. A systematic review was conducted, and identified studies from databases (PUBMED, EMBASE, EBSCO, Web of Science and Google Scholar) which were analyzed. The methodological quality of the selected publications was evaluated using the Newcastle-Ottawa Scale. Data were extracted from a total of 11 studies Fixed and random-effect model meta-analyses were performed. For the maintenance of muscle strength, Overall Neuropathy Limitations Scale (ONLS) data from 100 patients diagnosed with multifocal mononeuropathy (MMN) or chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) were pooled together. Switching to subcutaneous immunoglobulin administration led to a significant improvement (fixed effects model, p = 0.002). In data collected using the Medical Research Council Scale for Muscle Strength data from 140 patients with a wider range of disorders, a small but significant improvement in overall strength was observed in the SCIg group (p < 0.0001). In addition, the results of two studies measuring health-related quality of life and patient satisfaction were pooled. Data from 49 patients suffering from MMN, CIDP, and a variety of different myopathies demonstrated a small but significant increase in the mean 36-Item Short Form Survey (SF-36) scores (p < 0.0001). A highly significant difference was revealed when comparing data from 119 patients' responses to the Life Quality Index questionnaire (LQI) assessing patient satisfaction (p < 0.0001). This is the first analysis showing that SCIg is more effective than IVIg in improving Patient Reported Outcomes in auto-immune neuromuscular disease. These results should permit a broad range of patients to self-administer immunoglobulin treatments at home, potentially improving patient acceptability while reducing hospital visits and healthcare costs for the treatment of chronic auto-immune neuropathies.

Comparisons in fluctuation of muscle strength and function in patients with immune-mediated neuropathy treated with intravenous versus subcutaneous immunoglobulin

INTRODUCTION

Variations in muscle strength and function have not been studied in patients with chronic inflammatory demyelinating polyneuropathy and multifocal motor neuropathy whose treatment regimen has been changed from intravenous to subcutaneous immunoglobulin (IVIg to SCIg).

METHODS

In a prospective, open-label study, patients were changed from monthly IVIg to weekly SCIg. The primary endpoint was variation in isokinetic muscle strength (cIKS). Secondary endpoints were variations in Medical Research Council (MRC) score, grip strength (GS), 9-hole-peg test (9-HPT), and 40-meter-walk test (40-MWT).

RESULTS

The coefficient of variance of cIKS during the IVIg and SCIg treatment periods was unchanged (mean ± SD: 6.97 ± 4.83% vs. 5.50 ± 3.13%, P = 0.21). The variations in the 9-HPT and 40-MWT were significantly lower in the SCIg group (P = 0.01 and P = 0.005, respectively).

DISCUSSION

When therapy was changed from IVIg to SCIg, fluctuation of muscle strength was unchanged, but performance fluctuations were diminished. Muscle Nerve 57: 610-614, 2018.

Subcutaneous "bolus" immunoglobulin dose in CIDP: A proof-of concept study

BACKGROUND

Subcutaneous (SC) immunoglobulin (Ig) is an effective therapy for Chronic Inflammatory Demyelinating Polyradiculoneuropathy (CIDP). However, optimal dosage and frequency of administration remain to be clarified.

OBJECTIVES

We sought to assess the feasibility and tolerability of a novel regimen of SCIg administration, based on concentrated "bolus" doses delivered every other week, as compared to the "conventional" SCIg regimen, based on 1-3 administrations/week.

MATERIALS AND METHODS

Consecutively consenting CIDP patients (6 men and 1 woman) were crossed-over from SCIg "conventional" to SCIg "bolus" and followed-up for 6months. The main endpoints were: tolerability, defined as the percentage of patients successfully completing the study, patient's perceived disability, as measured by the Rasch-built Overall Disability Scale (R-ODS), life quality index (LQI), and inflammatory neuropathy cause and treatment (INCAT) scale.

RESULTS

SCIg "bolus" was well tolerated by all patients. The R-ODS score significantly improved (p=0.042), as well as the LQI sub-domains related to the interference of treatment in daily living activities (p=0.026), and therapy-related problems (p=0.039). No significant change was observed in the INCAT (p=0.317) score. There were no cases of drop-out and/or dose adjustment during follow-up.

CONCLUSIONS

SCIg "bolus" seems to represent an effective and well-tolerated option for CIDP maintenance therapy.

The electrophysiological response to immunoglobulin therapy in chronic inflammatory demyelinating polyneuropathy

OBJECTIVE

To characterize changes in motor nerve conduction studies (MNCS) and motor unit number index (MUNIX) following treatment with subcutaneous immunoglobulin and to assess whether these changes are related to muscle strength.

METHODS

Data from 23 patients participating in a randomized, controlled trial were analyzed. MNCS and MUNIX were performed before and after 12 weeks of treatment. Isokinetic strength (IMS) was measured in various muscles together with grip strength (GS).

RESULTS

Proximally evoked compound muscle action potential (CMAP) amplitudes and MUNIX tended to be better preserved in treated patients (P=.049 and .045). Changes in other parameters did not differ between groups. There was no correlation between changes in electrophysiological parameters and IMS. Changes in GS were related to median nerve motor conduction velocity, distal motor latency, CMAP amplitudes, and distally evoked CMAP duration (P=.013-.035).

CONCLUSION

Proximally evoked CMAP amplitudes appear to be the best MNCS parameter to assess treatment outcome in chronic inflammatory demyelinating polyneuropathy.

Subcutaneous immunoglobulin treatment in CIDP and MMN. Efficacy, treatment satisfaction and costs

Subcutaneous administration of immunoglobulin (SCIG) in chronic inflammatory demyelinating polyneuropathy (CIDP) and multifocal motor neuropathy (MMN) has been reported in several case reports and in a few randomized trials during the last decade. In this review we present the studies on SCIG in CIDP and MMN with special focus on the clinical effects. Moreover, the effect on quality of life, side effects to SCIG and the health economic perspectives are reviewed. Nine case studies, three randomized trials and six long-term, follow-up studies were identified. Most of the studies are conducted in patients switched from regular IVIG to SCIG treatment; one study involves treatment-naïve patients. The review shows that none of the studies have been powered to demonstrate an effect on disability. SCIG can maintain muscle strength for a period of 1 to 2years and ability seems preserved for a similar period. Quality of life is generally unchanged or improved after switch to SCIG and generalized side-effects seem fewer, whereas local reactions at the injection site occur. Health economic analyses favour SCIG at the doses used in the reviewed studies.

Subcutaneous immunoglobulin as first-line therapy in treatment-naive patients with chronic inflammatory demyelinating polyneuropathy: randomized controlled trial study

BACKGROUND AND PURPOSE

Subcutaneous immunoglobulin (SCIG) is effective as maintenance treatment in chronic inflammatory demyelinating polyneuropathy (CIDP). We investigated whether multiple subcutaneous infusions are as effective as conventional therapy with intravenous loading doses in treatment-naive patients with CIDP.

METHODS

Twenty patients fulfilling the clinical and electrophysiological criteria for CIDP were included and treated with either SCIG (0.4 g/kg/week) for 5 weeks or intravenous immunoglobulin (IVIG) (0.4 g/kg/day) for 5 days. After 10 weeks, patients were switched to the opposite treatment arm and followed for a further 10 weeks. All participants were evaluated at weeks 0, 2, 5 and 10 during both therapies. Primary outcome was combined isokinetic muscle strength (cIKS). Secondary outcomes were disability, clinical evaluation of muscle strength and the performance of various function tests.

RESULTS

All participants received both therapies, 14 completing the protocol. Overall, cIKS increased by 7.4 ± 14.5% (P = 0.0003) during SCIG and by 6.9 ± 16.8% (P = 0.002) during IVIG, the effect being similar (P = 0.80). Improvement of cIKS peaked 2 weeks after IVIG and 5 weeks after SCIG. Disability improved during SCIG treatment only. Muscle strength determined by manual muscle testing improved after 5 and 10 weeks during SCIG but only after 5 weeks during IVIG. The remaining parameters improved equally during both treatments. Plasma immunoglobulin G levels at baseline and improvement of cIKS were related.

CONCLUSION

In treatment-naive patients with CIDP, short-lasting SCIG and IVIG therapy improve motor performance to a similar degree, but with earlier maximal improvement following IVIG than SCIG treatment.

A new treatment regimen with high-dose and fractioned immunoglobulin in a special subgroup of severe and dependent CIDP patients

BACKGROUND

Chronic inflammatory demyelinating polyneuropathy (CIDP) is treated with intravenous immunoglobulins (IVIg), corticosteroids or plasma exchange (PE). IVIg dosage is not universal and markers for treatment management are needed.

METHODS

We report the response to high-dose and fractioned IVIg in a subgroup of definite CIDP patients, resistant to corticosteroids and PE, responders to IVIg but with an efficacy window <15 d.

RESULTS

Four patients were included with similar predominantly clinical motor form and conduction abnormalities. Treatment management consisted of fractioning IVIg and increasing the monthly cumulated dose (mean: 3 g/kg/month). Serum IgG concentration was measured and correlated to the clinical state. Monitoring of serum IgG helped to guide IVIg administration dosage and frequency. A mean of 10 months was required to improve symptoms; therapy was then switched to subcutaneous (SC) route (maintenance dose: 3.5 g/kg/month). The mean Overall Neuropathy Limitations Scale was improved from 11 to 3.2 and the mean Medical Research Council scale from 26 to 90.

CONCLUSION

It is important to distinguish patients with short IVIg efficacy window from those with classical resistance since the former may benefit from fractioning and increasing the IVIg dose. The monitoring of serum IgG level and its correlation to the clinical response could be of help in monitoring each individual's dosage.

Safety and Efficacy of Subcutaneous Immunoglobulin in the Treatment of Neuromuscular Disorders

Many neuromuscular diseases may be treated with immunoglobulins. In the United States, the major form of immunoglobulin used is intravenous (IV). Recently, there has been an increased interest in research regarding the use of subcutaneous immunoglobulin (SCIg), mainly for improved patient quality of life, convenience, potential for fewer systemic adverse events, and avoiding wear-off. The widespread use of the subcutaneous formulation in neurology has been affected by some limitations, mainly the smaller volume and higher frequency of infusions compared to IV administration. Also, there are different pharmacokinetic properties that should be considered to evaluate whether they change the immunomodulatory effect. There are several formulations available that address some limitations. Several studies have assessed efficacy, safety, and quality of life of SCIg in neurology. This review article summarizes the current evidence for the use of SCIg in neuromuscular diseases. It also addresses the pharmacokinetic differences and the different formulations available. The current available preliminary evidence indicates that SCIg is at least as effective as the IV formulations.

Subcutaneous immunoglobulin for maintenance treatment in chronic inflammatory demyelinating polyneuropathy (The PATH Study): study protocol for a randomized controlled trial

BACKGROUND

Subcutaneous administration of Ig (SCIg) has gained popularity as an alternative route of administration but has never been rigorously examined in chronic inflammatory demyelinating polyneuropathy (CIDP).

METHODS/DESIGN

The primary objective of the PATH study (Polyneuropathy and Treatment with Hizentra) is to determine the efficacy of two different doses of SCIg IgPro20 (0.2 g/kg bw or 0.4 g/kg bw) in a 24-week maintenance treatment of CIDP in comparison to placebo. The primary efficacy endpoint will be the proportion of patients who show CIDP relapse (1-point deterioration on the adjusted Inflammatory Neuropathy Cause and Treatment (INCAT) disability score) or are withdrawn within 24 weeks after randomization for any reason. IVIg-dependent adult patients with definite or probable CIDP according to the European Federation of Neurological Societies/Peripheral Nerve Society who fulfil the inclusion and exclusion criteria will be eligible. Based on sample-size calculation and relapse assumptions in the three arms, a sample size of 58 is needed per arm (overall sample size will be 350, of which 174 will be randomized). All eligible patients will progress through three study periods: an IgG dependency period (≤12 weeks) to select those who are Ig dependent; an IVIg restabilization period (10 or 13 weeks), which will be performed using the 10 % IgPro10 product; and an SC treatment period (24 weeks, followed by a 1-week completion visit after last follow-up). Patients showing IVIg restabilization will be randomized to demonstrate the efficacy of SCIg IgPro20 maintenance treatment over placebo. After completing the study, subjects are eligible to enter a long-term, open-label, extension study of 1 year or return to their previous treatment. In case of CIDP relapse during the 24-week SC treatment period, IgPro10 rescue medication will be offered. Safety, tolerability, and patients' preference of Ig administration route will be examined.

DISCUSSION

The PATH trial, which started in March 2012, is expected to finish at the end of 2016. The results will increase knowledge about the efficacy, safety, and tolerability of SCIg in maintenance management of CIDP patients.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT01545076 . Registered on 1 March 2012.

Subcutaneous immunoglobulins in the treatment of chronic immune-mediated neuropathies

Intravenous immunoglobulins represent an established therapy for the treatment of chronic immune-mediated neuropathies, specifically chronic inflammatory demyelinating polyradiculoneuropathies (CIDPs) as well as multifocal motor neuropathies (MMNs). For the treatment of antibody deficiency syndromes, subcutaneous immunoglobulins (SCIgs) have represented a mainstay for decades. An emerging body of evidence suggests that SCIg might also exhibit clinical efficacy in CIDP and MMN. This article reviews the current evidence for clinical effectiveness, as well as safety of SCIg for the treatment of immune-mediated neuropathies, and addresses remaining open questions in this context. We conclude that despite the need for controlled long-term studies to demonstrate long-term efficacy of SCIg in immune-mediated neuropathies, SCIg may already represent a potential therapeutic alternative for selected patients.

Treatment of patients with multifocal motor neuropathy with immunoglobulins in clinical practice: the SIGNS registry

OBJECTIVES

The management of patients with multifocal motor neuropathy (MMN) under everyday clinical conditions has been insufficiently studied. We therefore collected comprehensive observational data on patients with MMN who received intravenous (IV) or subcutaneous (SC) immunoglobulins (IGs) as maintenance therapy.

METHODS

This was a prospective, noninterventional study (registry) in neurological centres (hospitals and offices) throughout Germany.

RESULTS

As of 1 December 2015, 80 patients with MMN were included (mean age 55.4 ± 9.8 years, 67% males, mean disease duration 10.7 ± 10.2 years). The affected limb regions were predominantly distal muscle groups of the upper extremities. On the inflammatory neuropathy cause and treatment (INCAT) scale, 94% of the patients had some disability in the arms and 61% in the legs. At inclusion, 98.8% received IVIG and 1.3% SCIG. Substantial variation was observed between IVIG treatment intervals (every 0.7 to 17.3 weeks) and dosage (0.2-2.1 g/kg body weight received during a single administration; mean monthly dosage, 0.9 g/kg body weight). However, the mean monthly dosage was steady over time. At 1-year follow up, improvement was seen in muscle strength, INCAT and quality of life (QoL) scores (SF-36 questionnaire).

CONCLUSIONS

The management of patients with MMN in everyday clinical practice demonstrates a wide range of absolute dosages and treatment intervals of IG, supporting the recommended practice of determining treatment dose on an individual patient basis. The improvements in muscle strength and reduction in disability, accompanied by increased QoL, strengthen the case for use of IG as a maintenance treatment for MMN.

Intravenous immunoglobulin in the treatment of neurologic disorders

Intravenous immunoglobulins (IVIGs) are often used in the treatment of autoimmune disorders and immunodeficiencies, and it has been estimated that neurologic indications can account for up to 43% of IVIG used in clinical practice. In neurologic clinical practice, IVIG is used for acute therapy of newly diagnosed autoimmune disorders or exacerbations of pre-existing conditions, or as long-term maintenance treatment for chronic disorders. IVIG exerts its effects on humoral and cell-based immunity through multiple pathways, without a single dominant mechanism. Clinical use of IVIG has been supported by guidelines from American Academy of Neurology and European Federation of Neurologic Societies. IVIG is generally recommended for the treatment of Guillain-Barre syndrome and chronic inflammatory demyelinating polyneuropathy in adults, multifocal motor neuropathy and myasthenia gravis, and should be considered as a treatment option for dermatomyositis in adults and Lambert-Eaton myasthenic syndrome. Additional potential indications include stiff person syndrome, multiple sclerosis during pregnancy or while breastfeeding, refractory autoimmune epilepsy, and paraneoplastic disorders. Clinical use of IVIG is mostly safe but few adverse effects may still occur with potentially severe complications, including aseptic meningitis and thromboembolism. In addition to intravenous route (IVIG), subcutaneous immunoglobulins have been used as an alternative treatment option, especially in patients with limited intravenous access. Treatment with IVIG is effective in various autoimmune diseases, but its broader use is constrained by limited supply. This review evaluates the use of immunoglobulins in treatment of neurologic diseases.

Novel immunotherapeutic strategies in chronic inflammatory demyelinating polyneuropathy

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is a chronic immune-mediated neuropathy: it is clinically heterogeneous (relapsing-remitting form, chronic progressive form, monophasic form or CIDP having a Guillain-Barré syndrome-like onset), but potentially treatable. Although its pathophysiology remains largely unknown, CIDP is considered an immune-mediated neuropathy. Therefore, many immunotherapies have been proposed in this peripheral nervous system disorder, the most known efficient treatments being intravenous immunoglobulin, corticosteroids and plasma exchange. However, these therapies remain unsatisfactory for many patients, so numerous other immunotherapeutic strategies have been evaluated, based on their immunosuppressant or immunomodulatory potency. We have performed a large review of the literature about treatment in CIDP, with a special emphasis on novel and alternative immunotherapeutic strategies.

Immunotherapy in Peripheral Neuropathies

Immunotherapy has been investigated in a small subset of peripheral neuropathies, including an acute one, Guillain-Barré syndrome, and 3 chronic forms: chronic inflammatory demyelinating polyradiculoneuropathy, multifocal motor neuropathy, and neuropathy associated with IgM anti-myelin-associated glycoprotein. Several experimental studies and clinical data are strongly suggestive of an immune-mediated pathogenesis. Either cell-mediated mechanisms or antibody responses to Schwann cell, compact myelin, or nodal antigens are considered to act together in an aberrant immune response to cause damage to peripheral nerves. Immunomodulatory treatments used in these neuropathies aim to act at various steps of this pathogenic process. However, there are many phenotypic variants and, consequently, there is a significant difference in the response to immunotherapy between these neuropathies, as well as a need to improve our knowledge and long-term management of chronic forms.