Mycophenolate in treatment-resistant inflammatory neuropathies

European Academy of Neurology/Peripheral Nerve Society guideline on diagnosis and treatment of chronic inflammatory demyelinating polyradiculoneuropathy: Report of a joint Task Force-Second revision

OBJECTIVE

To revise the 2010 consensus guideline on chronic inflammatory demyelinating polyradiculoneuropathy (CIDP).

METHODS

Seventeen disease experts, a patient representative, and two Cochrane methodologists constructed 12 Population/Intervention/Comparison/Outcome (PICO) questions regarding diagnosis and treatment to guide the literature search. Data were extracted and summarized in GRADE summary of findings (for treatment PICOs) or evidence tables (for diagnostic PICOs).

RESULTS

Statements were prepared according to the GRADE Evidence-to-Decision frameworks. Typical CIDP and CIDP variants were distinguished. The previous term "atypical CIDP" was replaced by "CIDP variants" because these are well characterized entities (multifocal, focal, distal, motor, or sensory CIDP). The levels of diagnostic certainty were reduced from three (definite, probable, possible CIDP) to only two (CIDP and possible CIDP), because the diagnostic accuracy of criteria for probable and definite CIDP did not significantly differ. Good Practice Points were formulated for supportive criteria and investigations to be considered to diagnose CIDP. The principal treatment recommendations were: (a) intravenous immunoglobulin (IVIg) or corticosteroids are strongly recommended as initial treatment in typical CIDP and CIDP variants; (b) plasma exchange is strongly recommended if IVIg and corticosteroids are ineffective; (c) IVIg should be considered as first-line treatment in motor CIDP (Good Practice Point); (d) for maintenance treatment, IVIg, subcutaneous immunoglobulin or corticosteroids are recommended; (e) if the maintenance dose of any of these is high, consider either combination treatments or adding an immunosuppressant or immunomodulatory drug (Good Practice Point); and (f) if pain is present, consider drugs against neuropathic pain and multidisciplinary management (Good Practice Point).

European Academy of Neurology/Peripheral Nerve Society guideline on diagnosis and treatment of chronic inflammatory demyelinating polyradiculoneuropathy: Report of a joint Task Force-Second revision

To revise the 2010 consensus guideline on chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). Seventeen disease experts, a patient representative, and two Cochrane methodologists constructed 12 Population/Intervention/Comparison/Outcome (PICO) questions regarding diagnosis and treatment to guide the literature search. Data were extracted and summarized in GRADE summary of findings (for treatment PICOs) or evidence tables (for diagnostic PICOs). Statements were prepared according to the GRADE Evidence-to-Decision frameworks. Typical CIDP and CIDP variants were distinguished. The previous term "atypical CIDP" was replaced by "CIDP variants" because these are well characterized entities (multifocal, focal, distal, motor, or sensory CIDP). The levels of diagnostic certainty were reduced from three (definite, probable, possible CIDP) to only two (CIDP and possible CIDP), because the diagnostic accuracy of criteria for probable and definite CIDP did not significantly differ. Good Practice Points were formulated for supportive criteria and investigations to be considered to diagnose CIDP. The principal treatment recommendations were: (a) intravenous immunoglobulin (IVIg) or corticosteroids are strongly recommended as initial treatment in typical CIDP and CIDP variants; (b) plasma exchange is strongly recommended if IVIg and corticosteroids are ineffective; (c) IVIg should be considered as first-line treatment in motor CIDP (Good Practice Point); (d) for maintenance treatment, IVIg, subcutaneous immunoglobulin or corticosteroids are recommended; (e) if the maintenance dose of any of these is high, consider either combination treatments or adding an immunosuppressant or immunomodulatory drug (Good Practice Point); and (f) if pain is present, consider drugs against neuropathic pain and multidisciplinary management (Good Practice Point).

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.

Immunomodulatory treatment other than corticosteroids, immunoglobulin and plasma exchange for chronic inflammatory demyelinating polyradiculoneuropathy

BACKGROUND

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is a disease that causes progressive or relapsing and remitting weakness and numbness. It is probably caused by an autoimmune process. Immunosuppressive or immunomodulatory drugs would be expected to be beneficial. This review was first published in 2003 and has been updated most recently in 2016.

OBJECTIVES

To assess the effects of immunomodulatory and immunosuppressive agents other than corticosteroids, immunoglobulin, and plasma exchange in CIDP.

SEARCH METHODS

On 24 May 2016, we searched the Cochrane Neuromuscular Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL; 2016, Issue 4) in the Cochrane Library, MEDLINE, Embase, CINAHL, and LILACS for completed trials, and clinical trial registers for ongoing trials. We contacted the authors of the trials identified and other disease experts seeking other published and unpublished trials.

SELECTION CRITERIA

We sought randomised and quasi-randomised trials of all immunosuppressive agents, such as azathioprine, cyclophosphamide, methotrexate, ciclosporin, mycophenolate mofetil, and rituximab, and all immunomodulatory agents, such as interferon (IFN) alfa and IFN beta, in participants fulfilling standard diagnostic criteria for CIDP. We included all comparisons of these agents with placebo, another treatment, or no treatment.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. We wanted to measure the change in disability after one year as our primary outcome. Our secondary outcomes were change in disability after four or more weeks (from randomisation); change in impairment after at least one year; change in maximum motor nerve conduction velocity and compound muscle action potential amplitude after one year; and for participants who were receiving corticosteroids or intravenous immunoglobulin (IVIg), the amount of this medication given during at least one year after randomisation. Participants with one or more serious adverse events during the first year was also a secondary outcome.

MAIN RESULTS

Four trials fulfilled the selection criteria: one of azathioprine (27 participants), two of IFN beta-1a (77 participants in total) and one of methotrexate (60 participants). The risk of bias was considered low in the trials of IFN beta-1a and methotrexate but high in the trial of azathioprine. None of the trials showed significant benefit in any of the outcomes selected by their authors. The results of the outcomes which approximated most closely to the primary outcome for this review were as follows.In the azathioprine trial there was a median improvement in the Neuropathy Impairment Scale (scale range 0 to 280) after nine months of 29 points (range 49 points worse to 84 points better) in the azathioprine and prednisone treated participants compared with 30 points worse (range 20 points worse to 104 points better) in the prednisone alone group. There were no reports of adverse events.In a cross-over trial of IFN beta-1a with 20 participants, the treatment periods were 12 weeks. The median improvement in the Guy's Neurological Disability Scale (range 1 to 10) was 0.5 grades (interquartile range (IQR) 1.8 grades better to zero grade change) in the IFN beta-1a treatment period and 0.5 grades (IQR 1.8 grades better to 1.0 grade worse) in the placebo treatment period. There were no serious adverse events in either treatment period.In a parallel group trial of IFN beta-1a with 67 participants, none of the outcomes for this review was available. The trial design involved withdrawal from ongoing IVIg treatment. The primary outcome used by the trial authors was total IVIg dose administered from week 16 to week 32 in the placebo group compared with the IFN beta-1a groups. This was slightly but not significantly lower in the combined IFN beta-1a groups (1.20 g/kg) compared with the placebo group (1.34 g/kg, P = 0.75). There were four participants in the IFN beta-1a group and none in the placebo group with one or more serious adverse events, risk ratio (RR) 4.50 (95% confidence interval (CI) 0.25 to 80.05).The methotrexate trial had a similar design involving withdrawal from ongoing corticosteroid or IVIg treatment. At the end of the trial (approximately 40 weeks) there was no significant difference in the change in the Overall Neuropathy Limitations Scale, a disability scale (scale range 0 to 12), the median change being 0 (IQR -1 to 0) in the methotrexate group and 0 (IQR -0.75 to 0) in the placebo group. These changes in disability might have been confounded by the reduction in corticosteroid or IVIg dose required by the protocol. There were three participants in the methotrexate group and one in the placebo with one or more serious adverse events, RR 3.56 (95% CI 0.39 to 32.23).

AUTHORS' CONCLUSIONS

Low-quality evidence from randomised trials does not show significant benefit from azathioprine or interferon beta-1a and moderate-quality evidence from one randomised trial does not show significant benefit from a relatively low dose of methotrexate for the treatment of CIDP. None of the trials was large enough to rule out small or moderate benefit. The evidence from observational studies is insufficient to avoid the need for randomised controlled trials to discover whether these drugs are beneficial. Future trials should have improved designs, more sensitive outcome measures relevant to people with CIDP, and longer treatment durations.

Mycophenolate mofetil and neurological diseases

We describe experience with the use of mycophenolate mofetil (MMF) in neurological diseases. Although only small series of patients or case reports were described, MMF is promising in immune-mediated neuromuscular disorders. MMF has been used for the treatment of polymyositis, chronic inflammatory demyelinating polyradiculoneuropathy, and multifocal motor neuropathy. These studies showed that MMF is well tolerated and may be useful in some patients. MMF can be effective alone but mainly as an adjuvant therapy by reducing steroid requirements or the frequency of infusions of IVIg. MMF has also been tested alone as a single drug treatment or in combination with immunomodulatory drugs in multiple sclerosis in open surveillance trials or in phase II studies. None of these studies have been designed to demonstrate a clinical efficacy but preliminary results are very promising.

Immunosuppressant and immunomodulatory treatments for multifocal motor neuropathy

BACKGROUND

Multifocal motor neuropathy (MMN) is characterised by progressive, predominantly distal, asymmetrical limb weakness and usually multiple partial motor nerve conduction blocks. Intravenous immunoglobulin (IVIg) is beneficial but the role of immunosuppressive agents is uncertain. This is an update of a review first published in 2002 and previously updated in 2003, 2005, 2008 and 2011.

OBJECTIVES

To assess the effects of immunosuppressive agents for the treatment of multifocal motor neuropathy.

SEARCH METHODS

On 22 September 2014 we searched the Cochrane Neuromuscular Disease Group Specialized Register, CENTRAL, MEDLINE, EMBASE and LILACS for trials of MMN. We also searched two trials registers for ongoing studies.

SELECTION CRITERIA

We planned to include randomised controlled trials (RCTs) and quasi-RCTs. We considered prospective and retrospective case series and case reports in the Discussion.

DATA COLLECTION AND ANALYSIS

Two review authors searched the titles and abstracts of the articles identified and extracted the data independently.

MAIN RESULTS

Only one RCT of an immunosuppressive or immunomodulatory agent has been performed in MMN. This study randomised 28 participants and showed that mycophenolate mofetil, when used with IVIg, did not significantly improve strength, function or reduce the need for IVIg. No serious adverse events were observed. The study was deemed at low risk of bias. We summarised the results of retrospective and prospective case series in the discussion.

AUTHORS' CONCLUSIONS

According to moderate quality evidence, mycophenolate mofetil did not produce significant benefit in terms of reducing need for IVIg or improving muscle strength in MMN. Trials of other immunosuppressants should be undertaken.

Treatment of chronic inflammatory demyelinating polyneuropathy: from molecular bases to practical considerations

Chronic inflammatory demyelinating polyneuropathy (CIDP) is an autoimmune disease of the peripheral nervous system, in which both cellular and humoral immune responses are involved. The disease is clinically heterogeneous with some patients displaying pure motor form and others also showing a variable degree of sensory dysfunction; disease evolution may also differ from patient to patient, since monophasic, progressive, and relapsing forms are reported. Underlying such clinical variability there is probably a broad spectrum of molecular dysfunctions that are and will be the target of therapeutic strategies. In this review we first explore the biological bases of current treatments and subsequently we focus on the practical management that must also take into account pharmacoeconomic issues.

Immunomodulatory treatment other than corticosteroids, immunoglobulin and plasma exchange for chronic inflammatory demyelinating polyradiculoneuropathy

BACKGROUND

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is a disease causing progressive or relapsing and remitting weakness and numbness. It is probably due to an autoimmune process. Immunosuppressive or immunomodulatory drugs would be expected to be beneficial. This review was first published in 2003 and has been most recently updated in 2013.

OBJECTIVES

We aimed to review systematically the evidence from randomised trials of immunomodulatory and immunosuppressive agents other than corticosteroids, immunoglobulin and plasma exchange for CIDP.

SEARCH METHODS

On 9 July 2012, we searched the Cochrane Neuromuscular Disease Group Specialized Register (July 2012), CENTRAL (2012, Issue 6 in The Cochrane Library), MEDLINE (January 1977 to July 2012), EMBASE (January 1980 to July 2012), CINAHL (January 1982 to July 2012) and LILACS (January 1982 to July 2012). We contacted the authors of the trials identified and other disease experts seeking other published and unpublished trials.

SELECTION CRITERIA

We sought randomised and quasi-randomised trials of all immunosuppressive agents such as azathioprine, cyclophosphamide, methotrexate, ciclosporin, mycophenolate mofetil, and rituximab and all immunomodulatory agents such as interferon alfa and interferon beta, in participants fulfilling standard diagnostic criteria for CIDP.

DATA COLLECTION AND ANALYSIS

Two authors independently selected trials, judged their risk of bias and extracted data. We wanted to measure the change in disability after one year as our primary outcome. Our secondary outcomes were change in disability after four or more weeks (from randomisation), change in impairment after at least one year, change in maximum motor nerve conduction velocity and compound muscle action potential amplitude after one year and for those participants who were receiving corticosteroids or intravenous immunoglobulin, the amount of this medication given during at least one year after randomisation. Participants with one or more serious adverse events during the first year was also a secondary outcome.

MAIN RESULTS

Four trials fulfilled the selection criteria, one of azathioprine (27 participants), two of interferon beta-1a (77 participants in total) and one of methotrexate (60 participants). The risk of bias in the two trials of interferon beta-1a for CIDP and the trial of methotrexate was assessed to be low but bias in the trial of azathioprine was judged high. None of these trials showed significant benefit in the primary outcome (measured only in the methotrexate study) or secondary outcomes selected for this review. Severe adverse events occurred no more frequently than in the placebo groups for methotrexate and interferon beta-1a, but participant numbers were low. There was no adverse event reporting in the azathioprine study.

AUTHORS' CONCLUSIONS

The evidence from randomised trials does not show significant benefit from azathioprine, interferon beta-1a or methotrexate but none of the trials was large enough to rule out small or moderate benefit. The evidence from observational studies is insufficient to avoid the need for randomised controlled trials to discover whether these drugs are beneficial. Future trials should have improved designs, more sensitive outcome measures and longer durations.

Chronic inflammatory demyelinating polyradiculoneuropathy: from bench to bedside

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is the most common treatable chronic autoimmune neuropathy. Multiple diagnostic criteria have been established, with the primary goal of identifying neurophysiologic hallmarks of acquired demyelination. Treatment modalities have expanded to include numerous immunomodulatory therapies, although the best evidence continues to be for corticosteroids, plasma exchange, and intravenous immunoglobulin (IVIg). This review describes the pathology, epidemiology, pathogenesis, diagnosis, and treatment of CIDP.

Immunosuppressant and immunomodulatory treatments for multifocal motor neuropathy

BACKGROUND

Multifocal motor neuropathy is characterised by progressive, predominantly distal, asymmetrical limb weakness and usually multiple partial motor nerve conduction blocks. Intravenous immunoglobulin is beneficial but the role of immunosuppressive agents is uncertain. This is an update of a review first published in 2002 and previously updated in 2003, 2005 and 2008.

OBJECTIVES

To provide the best available evidence from randomised controlled trials on the role of immunosuppressive agents for the treatment of multifocal motor neuropathy.

SEARCH METHODS

We searched the Cochrane Neuromuscular Disease Group Specialized Register (4 October 2011), the Cochrane Central Register of Controlled Trials (CENTRAL) (2011, Issue 3 in The Cochrane Library), MEDLINE (January 1966 to September 2011), EMBASE (January 1980 to September 2011), and LILACS (January 1982 to September 2011) for trials of multifocal motor neuropathy.

SELECTION CRITERIA

We planned to include randomised and quasi-randomised controlled trials. We considered prospective and retrospective case series and case reports in the Discussion.

DATA COLLECTION AND ANALYSIS

Two review authors searched the titles and abstracts of the articles identified and extracted the data independently.

MAIN RESULTS

Only one randomised controlled trial of an immunosuppressive or immunomodulatory agent has been performed in multifocal motor neuropathy. This study randomised 28 participants and showed that mycophenolate mofetil, when used with intravenous immunoglobulin, did not significantly improve strength, function or reduce the need for intravenous immunoglobulin. No serious adverse events were observed. The study was deemed at low risk of bias. We summarised the results of retrospective and prospective case series in the discussion.

AUTHORS' CONCLUSIONS

According to moderate quality evidence, mycophenolate mofetil did not produce significant benefit in terms of reducing need for intravenous immunoglobulin or improving muscle strength. Trials of other immunosuppressants should be undertaken.

Standard and escalating treatment of chronic inflammatory demyelinating polyradiculoneuropathy

Chronic inflammatory demyelinating polyneuropathy (CIDP) is an acquired, immune-mediated polyradiculoneuritis that is progressive or relapsing over a period of at least 8 weeks. Although the exact pathogenesis is unclear, it is thought to be mediated by both cellular and humoral immune reactions directed against the peripheral nerve myelin or axon. CIDP also involves spinal nerve roots. Early medical treatment of CIDP is important to prevent axonal loss. Only three treatment regimens for CIDP have demonstrated benefit in randomized, controlled studies: corticosteroids, plasma exchange, and intravenous immunoglobulins (IVIg). Approximately 25% of patients respond inadequately to corticosteroids, plasma exchange or IVIg. Large placebo-controlled trials with alternative immunosuppressive compounds, e.g. mycophenolate mofetil, cyclosporine, cyclophosphamide, or monoclonal antibodies, are lacking.

Immunomodulatory treatment other than corticosteroids, immunoglobulin and plasma exchange for chronic inflammatory demyelinating polyradiculoneuropathy

BACKGROUND

Chronic inflammatory demyelinating polyradiculoneuropathy is a disease causing progressive or relapsing and remitting weakness and numbness. It is probably due to an autoimmune process. Immunosuppressive or immunomodulatory drugs would be expected to be beneficial.

OBJECTIVES

We aimed to review systematically the evidence from randomised trials of cytotoxic drugs and interferons other than corticosteroids, immunoglobulin and plasma exchange for chronic inflammatory demyelinating polyradiculoneuropathy.

SEARCH STRATEGY

We searched the Cochrane Neuromuscular Disease Group Specialised Register (May 2010), The Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, Issue 2), MEDLINE (January 1977 to May 2010), EMBASE (January 1980 to May 2010), CINAHL (January 1982 to May 2010) and LILACS (January 1982 to May 2010). We contacted the authors of the trials identified and other disease experts seeking other published and unpublished trials.

SELECTION CRITERIA

We sought randomised and quasi-randomised trials of all immunosuppressive agents such as azathioprine, cyclophosphamide, methotrexate, ciclosporin A, mycophenolate mofetil, and rituximab and all immunomodulatory agents such as interferon alfa and interferon beta in participants fulfilling standard diagnostic criteria for chronic inflammatory demyelinating polyradiculoneuropathy.

DATA COLLECTION AND ANALYSIS

Two authors independently selected trials, judged their methodological quality and extracted data. We wanted to measure the change in disability after one year as our primary outcome. Our secondary outcomes were change in disability after four or more weeks (from randomisation), change in impairment after at least one year, change in maximum motor nerve conduction velocity and compound muscle action potential amplitude after one year and for those participants who were receiving corticosteroids or intravenous immunoglobulin, the amount of this medication given during at least one year after randomisation. Participants with one or more serious adverse events during the first year was also a secondary outcome.

MAIN RESULTS

Four trials fulfilled the selection criteria, one of azathioprine (27 participants), two of interferon beta-1a (77 participants in total) and one of methotrexate (60 participants). None of these trials showed significant benefit in the primary outcome or secondary outcomes selected for this review.

AUTHORS' CONCLUSIONS

The evidence from randomised trials does not show significant benefit from azathioprine, interferon beta-1a or methotrexate but none of the trials was large enough to rule out small or moderate benefit. The evidence from observational studies is insufficient to avoid the need for randomised controlled trials to discover whether these drugs are beneficial. Future trials should have improved designs, more sensitive outcome measures and longer durations.

Treatment in inflammatory neuropathies

This review focuses on recent developments in the treatment of inflammatory neuropathies arising from immune dysregulation, rather than from infectious causes. The dysimmune inflammatory neuropathies are diseases of the peripheral nerves that have varying etiologies and may respond to immunomodulatory therapies. They are characterized by inflammatory changes in the nerve with associated destruction of myelin and axons. The underlying immune mechanisms are better understood in some of these conditions than others. Correct diagnosis and treatment is important to prevent clinical progression. Randomized controlled trials of some treatments in the more common inflammatory neuropathies have clarified their effectiveness; however, there are still groups of patients who are resistant to currently available treatments and for whom little effective treatment is available. Newer, targeted biologics and larger controlled trials of existing and novel therapies in these conditions offer promise of improved morbidity and mortality in this group of diseases.

Chronic inflammatory demyelinating polyradiculoneuropathy: a role for haematopoietic stem cell transplantation?

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is a clinical syndrome of a chronic progressive or relapsing and remitting, symmetrical, sensory and motor radiculoneuropathy. The immune reaction in CIDP is characterised by selective inflammation of peripheral nerves and is probably due to the interaction of cellular and humoral responses. Only three treatments for CIDP have demonstrated benefit in randomised studies, corticosteroids, plasma exchange and intravenous immunoglobulin. 25% of patients fail to respond or do not respond adequately to these treatments. Experimental data in animal models have shown that several autoimmune disorders, either congenital or acquired, can be transferred and/or treated by the transplantation of bone marrow stem cells. Haematopoietic stem cell transplantation (HSCT) has been performed with varying success in over 700 patients with autoimmune disorders throughout Europe. The experience in CIDP is very limited. This article will review current understanding of CIDP and experience of the use of HSCT in refractory CIDP.

Immunosuppressant and immunomodulatory treatments for multifocal motor neuropathy

BACKGROUND

Multifocal motor neuropathy is characterised by progressive, predominantly distal, asymmetrical limb weakness and usually multiple partial motor nerve conduction blocks. Intravenous immunoglobulin is beneficial but the role of immunosuppressive agents is uncertain.

OBJECTIVES

To provide the best available evidence from randomised controlled trials on the role of immunosuppressive agents for the treatment of multifocal motor neuropathy.

SEARCH STRATEGY

For this update, we searched the Cochrane Neuromuscular Disease Group Trials Register (October 8 2008), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2008, Issue 4), MEDLINE (from January 1966 to October 8 2008), and EMBASE (from January 1980 to October 8 2008), for trials of multifocal motor neuropathy.

SELECTION CRITERIA

Randomised and quasi-randomised controlled trials were to be included and one was found. Prospective and retrospective case series and case reports were considered in the Discussion.

DATA COLLECTION AND ANALYSIS

Two review authors searched the titles and abstracts of the articles identified and extracted the data independently.

MAIN RESULTS

In this update, we found the first randomised controlled trial of multifocal motor neuropathy. This study, which randomised 28 patients, showed that mycophenolate mofetil did not significantly improve strength or function or reduce the need for intravenous immunoglobulin. We summarised the results of retrospective and prospective case series in the discussion.

AUTHORS' CONCLUSIONS

In the only randomised placebo-controlled trial of any immunosuppressive agent, mycophenolate mofetil did not produce significant benefit. Trials of other immunosuppressants should be undertaken.

From bench to bedside--experimental rationale for immune-specific therapies in the inflamed peripheral nerve

Guillain-Barré syndrome and chronic inflammatory demyelinating polyradiculoneuropathy are autoimmune-mediated inflammatory diseases of the PNS. In recent years, substantial progress has been made towards understanding the immune mechanisms that underlie these conditions, in large part through the study of experimental models. Here, we review the available animal models that partially mimic human Guillain-Barré syndrome and chronic inflammatory demyelinating polyneuropathy, and discuss the wide range of therapeutic approaches that have been successfully established in these models of inflammatory neuropathies. Transfer of this preclinical knowledge to patients has been far less successful, and inflammatory neuropathies are still associated with significant morbidity and mortality. We will summarize successful therapeutic trials in human autoimmune neuropathies to provide a vantage point for the transfer of experimental treatment strategies to clinical practice in immune-mediated diseases of the peripheral nerve.

[Treatment options for chronic inflammatory demyelinating polyradiculoneuropathy (CIDP)]

Limits of treatment in chronic inflammatory demyelinating poly(radiculo)neuropathies (CIDP) patients are better known thanks to recent Cochrane reviews. (1) Randomized controlled trials have only focused on short-term effects, but most patients need long-term therapy, (2) There are three proven effective treatments available (prednisone; intravenous immunoglobulin or IVIg and plasma exchange or PE) which are useful in more than 60 p. 100 of patients, (3) New open studies indicated possible efficacy for mycophenolate, rituximab, etanercept, ciclosporine and interferons, and (4) Whether CIDP variants need specific treatment is still unknown. Many CIDP patients need treatment for years. The fear of side effects during long-term steroid treatment, the high costs of IVIg, the necessity for specialized equipment and the invasive nature of PE, are important factors determining the choice for one of these treatments. In most up-to-date treatment options, patients are initially treated with IVIg at a dosage of 2 g/kg administered for 25 days, clinical improvement can be judged within 10 days. The percentage of patients responding seems to be approximately 70 percent, with a very high chance (approximately 85 percent) that repeated administration of IVIg will be necessary, explaining why most neurologists add an immunosuppressive drug at this stage, but there is no consensus concerning the best drug to be used. Combinations of drugs are most likely to be useful in the next future, using IVIg, prednisone, and a immunosuppressor agent, such as mycophenolate, rituximab, etanercept, or ciclosporine. General measures to rehabilitate patients and to manage symptoms like fatigue and other residual findings are important.

Diagnosis and Treatment of Chronic Immune-mediated Neuropathies

The chronic autoimmune neuropathies are a diverse group of disorders, whose diagnosis and classification is based on the clinical presentations and results of ancillary tests. In chronic inflammatory demyelinating polyneuropathy, controlled therapeutic trials demonstrated efficacy for intravenous gamma-globulins, corticosteroids, and plasmaphereis. In multifocal motor neuropathy, intravenous gamma-globulins have been shown to be effective. In the other immune-mediated neuropathies, there are no reported controlled therapeutic trials, but efficacy has been reported for some treatments in non-controlled trials on case studies. Choice of therapy in individual cases is based on reported efficacy, as well as severity, progression, coexisting illness, predisposition to developing complications, and potential drug interactions.

Initial and long-term management of autoimmune neuropathies

The inflammatory neuropathies (chronic inflammatory demyelinating polyradiculoneuropathy [CIDP], Guillain-Barré syndrome [GBS] and multifocal motor neuropathy [MMN]) affect only one to two individuals per 100 000 of the population, but result in major disability and impairment. Intravenous immunoglobulin (IVIg) can be used as an initial treatment for CIDP, GBS and MMN. While plasma exchange and corticosteroids can also be used initially, they are not as uniformly effective for each of these disorders as IVIg. Substituting corticosteroids, plasma exchange or immunosuppressants may be appropriate for patients not responding to initial IVIg therapy, and combination therapy may be needed in some patients. There are no data from controlled clinical trials of long-term management strategies for CIDP and MMN; however, empirical evidence suggests that a positive long-term response to IVIg can be achieved by increasing the initial dose or its frequency of administration. Corticosteroids and immunosuppressants may be appropriate in some patients with CIDP. Adverse events with IVIg are usually mild and not treatment limiting; however, patients do need to be monitored for uncommon, but serious, adverse events such as renal insufficiency, stroke and thromboembolic events. Nevertheless, the safety profile of IVIg is exceptional relative to the potential complications of other long-term treatments for CIDP and MMN, especially corticosteroids and immunosuppressants. Predictors of response have been reported for each of the neuropathies, and until controlled clinical trials provide evidence on which to base treatment strategies, effective management will require individualising therapy according to patient response.

Treatment of immune-mediated, dysimmune neuropathies

This review focuses on the actual status and recent advances in the treatment of immune-mediated neuropathies, including: Guillain-Barre syndrome (GBS) with its subtypes acute inflammatory demyelinating polyradiculoneuropathy, acute motor axonal neuropathy, acute motor and sensory axonal neuropathy, Miller Fisher syndrome, and acute pandysautonomia; chronic inflammatory demyelinating polyneuropathy (CIDP) with its subtypes classical CIDP, CIDP with diabetes, CIDP/monoclonal gammopathy of undetermined significance (MGUS), sensory CIDP, multifocal motor neuropathy (MMN), multifocal acquired demyelinating sensory and motor neuropathy or Lewis-Sumner syndrome, multifocal acquired sensory and motor neuropathy, and distal acquired demyelinating sensory neuropathy; IgM monoclonal gammopathies with its subtypes Waldenstrom's macroglobulinemia, myelin-associated glycoprotein-associated gammopathy, polyneuropathy, organomegaly, endocrinopathy, M-protein, skin changes syndrome, mixed cryoglobulinemia, gait ataxia, late-onset polyneuropathy syndrome, and MGUS. Concerning the treatment of GBS, there is no significant difference between intravenous immunoglobulins (IVIG), plasma exchange or plasma exchange followed by IVIG. Because of convenience and absent invasiveness, IVIG are usually preferred. In treating CIDP corticosteroids, IVIG, or plasma exchange are equally effective. Despite the high costs and relative lack of availability, IVIG are preferentially used. For the one-third of patients, who does not respond, other immunosuppressive options are available. In MMN IVIG are the treatment of choice. Inadequate response in 20% of the patients requires adjunctive immunosuppressive therapies. Neuropathies with IgM monoclonal gammopathy may respond to various chemotherapeutic agents, although the long-term effects are unknown. In addition, such treatment may be associated with serious side effects. Recent data support the use of rituximab, a monoclonal antibody against the B-cell surface-membrane-marker CD20.

Mycophenolate mofetil and neurological diseases

We describe experience with the use of mycophenolate mofetil (MMF) in neurological diseases. Although only small series of patients or case reports were described, MMF is promising in immune-mediated neuromuscular disorders. MMF has been used for the treatment of polymyositis, chronic inflammatory demyelinating polyradiculoneuropathy, and multifocal motor neuropathy. These studies showed that MMF is well tolerated and may be useful in some patients. MMF can be effective alone but mainly as an adjuvant therapy by reducing steroid requirements or the frequency of infusions of IVIg. MMF has also been tested alone as a single drug treatment or in combination with immunomodulatory drugs in multiple sclerosis in open surveillance trials or in phase II studies. None of these studies have been designed to demonstrate a clinical efficacy but preliminary results are very promising.

Immunosuppressant and immunomodulatory treatments for multifocal motor neuropathy

BACKGROUND

Multifocal motor neuropathy is a distinct clinical entity characterised by progressive, predominantly distal, asymmetrical limb weakness and minimal sensory abnormality. The diagnostic feature of this condition is the presence of multiple partial motor nerve conduction blocks. Controlled trials have demonstrated the efficacy of regular intravenous immunoglobulin infusions. Immunosuppressive agents have been used as primary, second-line or adjunctive agents for its treatment. This review was undertaken to identify and review systematically randomised controlled trials of immunosuppressive agents. The use of intravenous immunoglobulin will be the subject of a separate review.

OBJECTIVES

To provide the best available evidence from randomised controlled trials on the role of immunosuppressive agents for the treatment of multifocal motor neuropathy.

SEARCH STRATEGY

We searched the Cochrane Neuromuscular Disease Group trials register for all trials of multifocal motor neuropathy published, using 'multifocal motor neuropathy' OR 'chronic inflammatory demyelinating polyradiculoneuropathy' OR ' conduction block' OR ' motor neuropathy' AND 'immunosuppressive agents', 'immunosuppressants', 'corticosteroids', 'plasma exchange', 'azathioprine', 'cyclophosphamide', 'cyclosporin', 'ciclosporin', 'methotrexate', and 'mycophenolate', 'immunomodulatory agents', 'interferon', 'total lymphoid irradiation' or 'bone marrow transplantation' as search terms. In addition we searched MEDLINE, EMBASE for 2000 and 2001 and CINAHL, LILACS for all years. We updated the register search in February 2004 and searched MEDLINE (January 1966 to end May 2004) and EMBASE (January 1980 to end May 2004).

SELECTION CRITERIA

All randomised controlled trials and quasi-randomised clinical trials in which allocation was not random but was intended to be unbiased (e.g. alternate allocation) were to have been selected. Since no such trials were discovered, all prospective and retrospective case series were included in the 'background' or 'discussion' sections of the review.

DATA COLLECTION AND ANALYSIS

All studies on multifocal motor neuropathy or lower motor neuron weakness with conduction block and no sensory abnormality were scrutinised for data on patients treated with any form of immunosuppressive agents besides intravenous immunoglobulin. The information on the outcome of treatment was then collated and summarised.

MAIN RESULTS

We found no randomised controlled trials of any immunosuppressive agents for multifocal motor neuropathy. We summarised the results of retrospective and prospective case series in the discussion of the review.

AUTHORS' CONCLUSIONS

There are no randomised controlled trials to indicate whether immunosuppressive agents are beneficial in multifocal motor neuropathy.

Multifocal motor neuropathy: current concepts and controversies

Multifocal motor neuropathy (MMN) is now a well-defined purely motor multineuropathy characterized by the presence of multifocal partial motor conduction blocks (CB), frequent association with anti-GM1 IgM antibodies, and usually a good response to high-dose intravenous immunoglobulin (IVIg) therapy. However, several issues remain to be clarified in the diagnosis, pathogenesis, and therapy of this condition including its nosological position and its relation to other chronic dysimmune neuropathies; the degree of CB necessary for the diagnosis of MMN; the existence of an axonal form of MMN; the pathophysiological basis of CB; the pathogenetic role of antiganglioside antibodies; the mechanism of action of IVIg treatments in MMN and the most effective regimen; and the treatment to be used in unresponsive patients. These issues are addressed in this review of the main clinical, electrophysiological, immunological, and therapeutic features of this neuropathy.

Treatment of chronic inflammatory demyelinating polyneuropathy

PURPOSE OF REVIEW

Chronic inflammatory demyelinating poly(radiculo)neuropathy (CIDP) is a treatable disorder. There are three proven effective treatments available. Randomized controlled trials have only focused on short-term effects, but most patients need long-term therapy. The most up-to-date treatment options are discussed. Attention is also paid to the use of appropriate assessment scales and treatment of residual findings.

RECENT FINDINGS

A Cochrane review is available indicating that intravenous immunoglobulin is an effective treatment. Equal efficacy of intravenous immunoglobulin and steroids was shown during a 6-week treatment period. New open studies indicated possible efficacy for mycophenolate, interferon-beta and etanercept. Combinations of treatment are scarcely studied yet. Some CIDP patients may have a more acute onset of disease since maximum severity is reached within 4-8 weeks, resulting in confusion about the diagnosis. It was shown that severe fatigue can be a major complaint in CIDP patients; a training regimen might partially resolve these problems.

SUMMARY

CIDP is a treatable disorder, but most patients need long-term treatment. Intravenous immunoglobulin, steroids and plasma exchange are shown to be effective. It is suggested that other immunomodulatory agents can also be effective, but randomized trials are needed to confirm these benefits. General measures to rehabilitate patients and to manage symptoms like fatigue and other residual findings are important.

Treatment of Guillain-Barre syndrome and CIDP

Guillain-Barré syndrome (GBS) and chronic inflammatory demyelinating poly-(radiculo)neuropathy (CIDP) are immune-mediated disorders with a variable duration of progression and a range in severity of weakness. Infections can trigger GBS and exacerbate CIDP. Anti-ganglioside antibodies are important, but there is debate on the role of genetic factors in the pathogenesis of these disorders. Randomized controlled trials (RCT) have shown that intravenous immunoglobulin (IVIg) and plasma exchange (PE) are effective in both GBS and CIDP. Most CIDP patients also improve after steroid therapy. Despite current treatment options, many patients have residual deficits or need to be treated for a long period of time. Therefore, new treatment trials are highly indicated. This review focuses on the current and possible new treatment options that could be guided by recent results from laboratory experiments.

Chronic inflammatory demyelinating polyneuropathy – update on pathogenesis, diagnostic criteria and therapy

PURPOSE OF REVIEW

Chronic inflammatory demyelinating polyneuropathy (CIDP) is a treatable but possibly underdiagnosed disorder of the peripheral nerve. This review covers the growing literature of the past years that deals with the pathogenesis, diagnostic criteria and treatment of CIDP.

RECENT FINDINGS

The recent development of a biphasic animal model of experimental autoimmune neuritis may provide further insights into the pathogenesis of inflammatory demyelination of the peripheral nerve, such as in CIDP, and may allow the development of further innovative therapeutic strategies. In patients, the contribution of immune processes to the dysfunction in hereditary polyneuropathies and the association of hereditary neuropathy and CIDP has been described. Commonly used therapies remain corticosteroids, intravenous immunoglobulin and plasmapheresis; however, newer immunosuppressant approaches using mycophenolate mofetil or cyclosporin A, or immunomodulating therapies using monoclonal antibodies or interferons are presently under investigation.

SUMMARY

The growing body of knowledge on the pathogenesis of CIDP and further diagnostic differentiation of subforms may help to develop more-effective therapies for CIDP in the next few years.

IVIg in idiopathic autoimmune neuropathies: analysis in the light of the latest results

High-dose intravenous immunoglobulin (IVIg) is effective in the treatment of idiopathic autoimmune neuropathies including Guillain-Barré syndrome (GBS), chronic inflammatory demyelinating neuropathy (CIDP) and multifocal motor neuropathy (MMN), representing a useful option or, as in MMN, the gold standard for their treatment. In GBS, two randomised, controlled trials (RCT) showed that IVIg is at least as effective as plasma exchange (PE). IVIg may however be preferred due to its low number of contraindications and complications and the fact that it can be administered at any time, in any department, including patients with contraindications to PE, or in intensive care units. In CIDP, at least four RCTs have demonstrated the efficacy of IVIg in over 60% of CIDP patients, while two additional RCTs have shown a comparable effect to steroids and PE as initial treatment. As with PE, the effects of IVIg usually last a few weeks meaning that the majority of patients require periodic maintenance infusions. The lower cost and easier administration of oral steroids compared to IVIg may be partly compensated by the safer long-term profile of IVIg over steroids. In MMN, almost 80% of patients improve with IVIg, the efficacy of which has been confirmed by four RCTs, making of IVIg the first-choice therapy in MMN, for which steroids and PE are ineffective or even detrimental. Also in these patients, IVIg induces a rapid improvement that usually lasts only a few weeks and has to be maintained with periodic IVIg infusions for long periods of time, if not indefinitely.

A review of the medical management of chronic inflammatory demyelinating polyradiculoneuropathy

Chronic idiopathic demyelinating polyradiculoneuropathy (CIDP) is a rare condition, but merits consideration due to its disabling consequences for patients and the growing existence of efficacious therapies during the last few decades. The first step is to characterise this neuropathy among the chronic dysimmune polyneuropathies, according to clinical, electrophysiologicalal and sometimes pathologicalal and immunochemical criteria. Typical CIDP is currently defined by criteria which have progressively improved since the first attempt made by an Ad Hoc Subcommittee of the American Academy of Neurology in 1991. However, CIDP may be associated with several concurrent diseases, and other chronic demyelinating polyneuropathies may be considered as either subtypes of CIDP, such as sensory CIDP and multifocal acquired sensory and motor neuropathy, or frontiers of CIDP, such as multi-focal motor neuropathy and polyneuropathy associated with monoclonal gammopathy. These considerations are helpful in the choice of treatments, as the response to immunomodulatory agents is different according to the type of the dysimmune neuropathy. CIDP is considered to be an immune-mediated disorder and may respond dramatically to numerous short-term therapies, such as corticosteroids, plasma exchanges, or intravenous immunoglobulin. The aim of this review is both to summarise the main results of the published open and randomised controlled trials for CIDP, and to provide some information about randomised controlled trials currently in progress. The objectives of the current and future trials are firstly, to choose the best regimen for short-term treatments, and secondly, to test new immunosuppressants in long-term therapy, if the neurological condition requires it.

Treatment of dysimmune neuropathies

Several therapies are currently used in dys-immune neuropathies including steroids,plasma exchange (PE), high-dose intravenous immunoglobulins(IVIg), and immuno-suppressive agents (IS). Even if there is substantial evidence that these treatments may improve the course of the neuropathy, their effectiveness is far from being complete and is sometime hampered by the occurrence of associated side effects. In Guillain-Barré syndrome (GBS),IVIg and PE are similarly effective in accelerating the recovery but there is still little evidence that they can reduce mortality or long-term disability. Recent reports on the association of intravenous methylprednisolone or interferon-beta (IFN-beta) to IVIg did not result in significant further improvement. In chronic inflammatory demyelinating polyradiculoneuropathy(CIDP) steroids, PE, and IVIG are initially similarly effective. The short-term effect of PE and IVIgand the side effects associated with the long-term use of steroids have prompted the use of several IS, interferon and,more recently, the anti-CD20 monoclonal-antibody Rituximab, but their efficacy has still to be proved in controlled studies. The recent identification of multifocal motor neuropathy(MMN) was shortly followed by the finding of an effective therapy. Almost 80% of patients respond toIVIg whose effect needs to be maintained with periodic infusions for long periods of time, and tends to decrease after several years. Also in this condition a number of immune modulating agents have been used to reduce the frequency or improve the effectiveness of IVIg,but their efficacy has not been sofar confirmed in randomized trials. Similar conclusions can be drawn for neuropathies associated with monoclonal gammopathies where only PE and IVIg have proved to be effective in controlled studies,while the promising initial results obtained with Rituximab in neuropathy associated IgM monoclonal gammopathy awaits confirmation from controlled trials.

Cytotoxic drugs and interferons for chronic inflammatory demyelinating polyradiculoneuropathy

BACKGROUND

Chronic inflammatory demyelinating polyradiculoneuropathy is a disease causing progressive or relapsing and remitting weakness and numbness. It is probably due to an autoimmune inflammatory process. Immunosuppressive or immunomodulatory drugs would be expected to be beneficial.

OBJECTIVES

We aimed to review systematically the evidence from randomised trials concerning cytotoxic drugs and interferons for chronic inflammatory demyelinating polyradiculoneuropathy.

SEARCH STRATEGY

We searched the Cochrane Neuromuscular Disease Group trials register (searched May 2004), MEDLINE (searched January 1977 to May 2004), EMBASE (January 1980 to May 2004), CINAHL (searched January 1982 to December 2001) and LILACS (searched January 1982 to December 2001). We contacted the authors of the trials identified and other disease experts seeking other published and unpublished trials.

SELECTION CRITERIA

We sought randomised and quasi-randomised trials of all immunosuppressive agents such as azathioprine, cyclophosphamide, methotrexate, cyclosporin A, mycophenolate mofetil, and rituximab and all immunomodulatory agents such as alpha interferon and beta interferon in participants fulfilling standard diagnostic criteria for chronic inflammatory demyelinating polyradiculoneuropathy.

DATA COLLECTION AND ANALYSIS

Two of us independently selected the trials which met our criteria, judged their methodological quality and extracted the data onto specially designed forms. We wanted to measure the change in disability after one year as our primary outcome measure.

MAIN RESULTS

We found one parallel group open trial of azathioprine for nine months involving 27 participants and another of interferon beta involving 10 participants in a double blind crossover trial with each treatment period lasting 12 weeks. Neither trial provided our primary outcome measure and neither showed a significant beneficial effect on any of the outcome measures selected by the authors or ourselves in the protocol for this review.

REVIEWERS' CONCLUSIONS

The evidence is inadequate to decide whether azathioprine, interferon beta or any other immunosuppressive drug or interferon is beneficial in chronic inflammatory demyelinating polyradiculoneuropathy.

Advances in understanding and treatment of immune-mediated disorders of the peripheral nervous system

During recent years, novel insights in basic immunology and advances in biotechnology have contributed to an increased understanding of the pathogenetic mechanisms of immune-mediated disorders of the peripheral nervous system. This increased knowledge has an impact on the management of patients with this class of disorders. Current advances are outlined and their implication for therapeutic approaches addressed. As a prototypic immune-mediated neuropathy, special emphasis is placed on the pathogenesis and treatment of the Guillain-Barré syndrome and its variants. Moreover, neuropathies of the chronic inflammatory demyelinating, multifocal motor, and nonsystemic vasculitic types are discussed. This review summarizes recent progress with currently available therapies and--on the basis of present immunopathogenetic concepts--outlines future treatment strategies.