Magnetic resonance outcome measures in multiple sclerosis trials: time to rethink?

PURPOSE OF REVIEW

We summarize MRI measures currently available to assess treatment efficacy and safety in multiple sclerosis (MS) clinical trials and discuss novel metrics that could enter the clinical arena in the near future.

RECENT FINDINGS

In relapsing remitting MS, MRI measures of disease activity (new T2 and gadolinium-enhancing lesions) provide a good surrogacy of treatment effect on relapse rate and disability progression; however, their value in progressive MS remains elusive. For the progressive disease forms, these measures need to be combined with quantities assessing the extent of irreversible tissue loss, which have already been introduced in some clinical trials (e.g., evolution of active lesions into permanent black holes and brain atrophy). Novel measures (e.g., quantification of gray matter and spinal cord atrophy) have demonstrated a great value in explaining patients' clinical outcome, but still need to be fully validated. Despite showing promise, evaluations of cortical lesions, of microscopic tissue abnormalities, and of functional cortical reorganization are still some way off for monitoring of treatment effects.

SUMMARY

Trial outcomes in MS should include measures of inflammation and neurodegeneration, which should be combined according to the disease clinical phenotype, phase of the study, and the supposed mechanism of action of the drug tested.

Relapses and disability accumulation in progressive multiple sclerosis

OBJECTIVE

We examined the effect of relapses-before and after progression onset-on the rate of postprogression disability accrual in a progressive multiple sclerosis (MS) cohort.

METHODS

We studied patients with primary progressive MS (n = 322) and bout-onset progressive MS (BOPMS) including single-attack progressive MS (n = 112) and secondary progressive MS (n = 421). The effect of relapses on time to Expanded Disability Status Scale (EDSS) score of 6 was studied using multivariate Cox regression analysis (sex, age at progression, and immunomodulation modeled as covariates). Kaplan-Meier analysis was performed using EDSS 6 as endpoint.

RESULTS

Preprogression relapses (hazard ratio [HR]: 1.63; 95% confidence interval [CI]: 1.34-1.98), postprogression relapses (HR: 1.37; 95% CI: 1.11-1.70), female sex (HR: 1.19; 95% CI: 1.00-1.43), and progression onset after age 50 years (HR: 1.47; 95% CI: 1.21-1.78) were associated with shorter time to EDSS 6. Postprogression relapses occurred in 29.5% of secondary progressive MS, 10.7% of single-attack progressive MS, and 3.1% of primary progressive MS. Most occurred within 5 years (91.6%) after progressive disease onset and/or before age 55 (95.2%). Immunomodulation after onset of progressive disease course (HR: 0.64; 95% CI: 0.52-0.78) seemingly lengthened time to EDSS 6 (for BOPMS with ongoing relapses) when analyzed as a dichotomous variable, but not as a time-dependent variable.

CONCLUSIONS

Pre- and postprogression relapses accelerate time to severe disability in progressive MS. Continuing immunomodulation for 5 years after the onset of progressive disease or until 55 years of age may be reasonable to consider in patients with BOPMS who have ongoing relapses.

Brain atrophy in natalizumab-treated patients: A 3-year follow-up

Background:

A pseudoatrophy effect has been held responsible for the lack of net impact of natalizumab on brain volume outcomes in 2-year trials, but no data are available beyond 24 months.

Objective:

We aimed to investigate brain volume dynamics in natalizumab-treated patients in up to 3 years after therapy initiation with clinical correlations.

Methods:

Patients on natalizumab for at least 3 years were clinically assessed 3-monthly. Magnetic resonance imaging scans were performed at baseline and yearly. Brain volume changes were obtained with SIENA. Multivariate models were used to investigate the association between baseline inflammation and changes in brain volume and disability.

Results:

Sixty-two patients with multiple sclerosis were analysed. Mean age and disease duration were 34.7 (SD: 8.3) and 10.4 (SD: 6.6) years. Presence of gadolinium enhancement at baseline was not associated with Expanded Disability Status Scale changes ( p=0.468), but was associated with larger brain volume decreases ( p=0.005) in the first ( p=0.024) and second year ( p=0.019) but not in the third year ( p=0.863). Brain volume changes at 12 and 36 months were marginally associated with disability status at month 12 ( p=0.094) and 36 ( p=0.084), respectively.

Conclusions:

Baseline inflammation affects brain volume measures up to 24 months after natalizumab initiation. A marginal association of brain volume changes with disability is present.

Fumarate treatment in progressive forms of multiple sclerosis: first results of a single-center observational study

OBJECTIVES

Therapeutic options in progressive forms of multiple sclerosis (MS) are still limited. Dimethyl fumarate (DMF) has immunomodulatory properties but may also exert antioxidative cytoprotective effects. Hence, it may be a therapeutic option for progressive MS. The aim of this observational study was to evaluate safety, adherence and efficacy of fumarates in patients with primary progressive MS (PPMS) or secondary progressive MS.

METHODS

Patients with progressive MS whose condition had failed to respond to standard therapies and had worsened received the fumarate mixture Fumaderm, licensed for psoriasis therapy in Germany, or DMF by pharmaceutical preparation (Bochum ethics approval no. 4797-13). At regular follow-up visits, tolerability and disease course were assessed.

RESULTS

Twenty-six patients [age 54 ± 7.8 years; female = 13 (50%); PPMS = 12 (46.2%); Expanded Disability Status Scale (EDSS) = 6.0 ± 0.4 (range 3.5-8.0); disease duration = 14.1 ± 8.7 years] were initiated on treatment with Fumaderm (n = 18) or pharmacy-prepared DMF (n=8). During a mean follow-up period of 13.2 ± 7.5 months (range 6-30) only five patients (19.2%) reported minor complaints. In 15 patients (57.7%) EDSS remained stable. In five cases (19.2%) there was even a decrease in EDSS while in six patients (23.1%) there was an increase in EDSS of more than 0.5 points, reflecting deterioration. Laboratory values were controlled for lymphopenia, renal and hepatic values, without any safety problems. We observed no significant differences between the two pharmaceutical forms.

CONCLUSION

Our pilot data indicate that fumarate therapy appears to be safe and well tolerated by patients with progressive MS. In more than 75% of cases no further disease progression was evident. However, controlled studies are warranted to evaluate the detailed therapeutic potential of fumarates and their long-term effects in progressive MS.

Disease-modifying treatments for progressive multiple sclerosis

The last 20 years have seen major progress in the treatment of relapsing-remitting multiple sclerosis (RRMS) using a variety of drugs targeting immune dysfunction. In contrast, all clinical trials of such agents in primary progressive multiple sclerosis (PPMS) have failed and there is limited evidence of their efficacy in secondary progressive disease. Evolving concepts of the complex interplay between inflammatory and neurodegenerative processes across the course of multiple sclerosis (MS) may explain this discrepancy. This paper will provide an up-to-date overview of the rationale and results of the published clinical trials that have sought to alter the trajectory of both primary and secondary MS, considering studies involving drugs with a primary immune target and also those aiming for neuroprotection. Future areas of study will be discussed, building on these results combined with the experience of treating RRMS and new concepts emerging from laboratory science and animal models.

Validating predictors of disease progression in a large cohort of primary-progressive multiple sclerosis based on a systematic literature review

BACKGROUND

New agents with neuroprotective or neuroregenerative potential might be explored in primary-progressive Multiple Sclerosis (PPMS)--the MS disease course with leading neurodegenerative pathology. Identification of patients with a high short-term risk for progression may minimize study duration and sample size. Cohort studies reported several variables as predictors of EDSS disability progression but findings were partially contradictory.

OBJECTIVE

To analyse the impact of published predictors on EDSS disease progression in a large cohort of PPMS patients.

METHODS

A systematic literature research was performed to identify predictors for disease progression in PPMS. Individual case data from the Sylvia Lawry Centre (SLC) and the Hamburg MS patient database (HAPIMS) was pooled for a retrospective validation of these predictors on the annualized EDSS change.

RESULTS

The systematic literature analysis revealed heterogeneous data from 3 prospective and 5 retrospective natural history cohort studies. Age at onset, gender, type of first symptoms and early EDSS changes were available for validation. Our pooled cohort of 597 PPMS patients (54% female) had a mean follow-up of 4.4 years and mean change of EDSS of 0.35 per year based on 2503 EDSS assessments. There was no significant association between the investigated variables and the EDSS-change.

CONCLUSION

None of the analysed variables were predictive for the disease progression measured by the annualized EDSS change. Whether PPMS is still unpredictable or our results may be due to limitations of cohort assessments or selection of predictors cannot be answered. Large systematic prospective studies with new endpoints are needed.

Pharmacological treatment for memory disorder in multiple sclerosis

BACKGROUND

This is an update of the Cochrane review "Pharmacologic treatment for memory disorder in multiple sclerosis" (first published in The Cochrane Library 2011, Issue 10).Multiple sclerosis (MS) is a chronic immune-mediated, inflammatory, demyelinating, neurodegenerative disorder of the central nervous system (CNS) and can cause both neurological and neuropsychological disability. Both demyelination and axonal and neuronal loss are believed to contribute to MS-related cognitive impairment. Memory disorder is one of the most frequent cognitive dysfunctions and presents a considerable burden to people with MS and to society due to the negative impact on function. A number of pharmacological agents have been evaluated in many existing randomised controlled trials for their efficacy on memory disorder in people with MS but the results were not consistent.

OBJECTIVES

To assess the absolute and comparative efficacy, tolerability and safety of pharmacological treatments for memory disorder in adults with MS.

SEARCH METHODS

We searched the Cochrane Multiple Sclerosis and Rare Diseases of the Central Nervous System Group Trials Register (24 July 2013), PsycINFO (January 1980 to 26 June 2013) and CBMdisc (1978 to 24 June 2013), and checked reference lists of identified articles, searched some relevant journals manually, registers of clinical trials and published abstracts of conference proceedings.

SELECTION CRITERIA

All double-blind, randomised controlled parallel trials on pharmacological treatment versus placebo or one or more pharmacological treatments in adults with MS who had at least mild memory impairment (at 0.5 standard deviations below age- and sex-based normative data on a validated memory scale). We placed no restrictions regarding dose, route of administration and frequency; however, we only included trials with an administration duration of 12 weeks or greater.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial quality and extracted data. We discussed disagreements and resolved them by consensus among review authors. We contacted principal investigators of included studies for additional data or confirmation.

MAIN RESULTS

We included seven randomised controlled trials (RCTs) involving 625 people mostly with relapsing-remitting, secondary-progressive and primary-progressive MS, evaluating the absolute efficacy of donepezil, ginkgo biloba, memantine and rivastigmine versus placebo in improving memory performance with diverse assessment scales. Overall, clinical and methodological heterogeneities existed across these studies. Moreover, most of them had methodological limitations on non-specific selections of targeted sample, non-matched variables at baseline or incomplete outcome data (high attrition bias). Only the two studies on donepezil had clinical and methodological homogeneity and relatively low risks for bias. One RCT evaluating estriol versus placebo is currently ongoing.We could not carry out a meta-analysis due to the heterogeneities across studies and the high attrition bias. A subgroup analysis for donepezil versus placebo showed no treatment effects on total recall on the Selective Reminding Test (mean difference (MD) 1.68; 95% confidence interval (CI) -2.21 to 5.58), total correct scores on the 10/36 Spatial Recall Test (MD -0.93; 95% CI -3.18 to 1.32), the Symbol Digit Modalities Test (MD -1.27; 95% CI -3.15 to 0.61) and the Paced Auditory Serial Addition Test (2+3 sec) (MD 2.23; 95% CI -1.87 to 6.33). Concerning safety, the main adverse events were: diarrhoea (risk ratio (RR) 3.88; 95% CI 1.66 to 9.05), nausea (RR 1.71; 95% CI 0.93 to 3.18) and abnormal dreams (RR 2.91; 95% CI 1.38 to 6.14). However, the results in both studies were subjected to a serious imprecision resulting from the small sample sizes and the low power of test (lower than 80%), which contributed to a moderate quality of the evidence. No serious adverse events were attributed to the treatments in all experimental groups.

AUTHORS' CONCLUSIONS

We found no convincing evidence to support the efficacy of pharmacological symptomatic treatment for MS-associated memory disorder because most of available RCTs had a limited quality. Whether pharmacological treatment is effective for memory disorder in patients with MS remains inconclusive. However, there is moderate-quality evidence that donepezil 10 mg daily was not effective in improving memory in MS patients with mild memory impairment, but had a good tolerability. Adverse events such as nausea, diarrhoea and abnormal dreams were not frequent but were associated with treatment. Ginkgo biloba, memantine and rivastigmine were safe and well tolerated and no serious adverse effects were reported. Future large-scale RCTs with higher methodological quality are needed.

Primary progressive multiple sclerosis: progress and challenges

Primary progressive multiple sclerosis (MS) has long been recognised as presenting great difficulties to our management of what is increasingly a treatable neurological disease. Here we review some basic and clinical aspects of primary progressive MS, and describe how the disorder in fact offers powerful insights and opportunities for better understanding multiple sclerosis, and from a practical perspective an invaluable clinical substrate for studying and treating progressive disability in MS. Difficult hurdles remain, however, and these too are reviewed.

Immunotherapy of multiple sclerosis: the state of the art

It is widely accepted that the main common pathogenetic pathway in multiple sclerosis (MS) involves an immune-mediated cascade initiated in the peripheral immune system and targeting CNS myelin. Logically, therefore, the therapeutic approaches to the disease include modalities aiming at downregulation of the various immune elements that are involved in this immunologic cascade. Since the introduction of interferons in 1993, which were the first registered treatments for MS, huge steps have been made in the field of MS immunotherapy. More efficious and specific immunoactive drugs have been introduced and it appears that the increased specificity for MS of these new treatments is paralleled by greater efficacy. Unfortunately, this seemingly increased efficacy has been accompanied by more safety issues. The immunotherapeutic modalities can be divided into two main groups: those affecting the acute stages (relapses) of the disease and the long-term treatments that are aimed at preventing the appearance of relapses and the progression in disability. Immunomodulating treatments may also be classified according to the level of the 'immune axis' where they exert their main effect. Since, in MS, a neurodegenerative process runs in parallel and as a consequence of inflammation, early immune intervention is warranted to prevent progression of relapses of MS and the accumulation of disability. The use of neuroimaging (MRI) techniques that allow the detection of silent inflammatory activity of MS and neurodegeneration has provided an important tool for the substantiation of the clinical efficacy of treatments and the early diagnosis of MS. This review summarizes in detail the existing information on all the available immunotherapies for MS, old and new, classifies them according to their immunologic mechanisms of action and proposes a structured algorithm/therapeutic scheme for the management of the disease.

Immunomodulators and immunosuppressants for multiple sclerosis: a network meta-analysis

BACKGROUND

Different therapeutic strategies are available for treatment of multiple sclerosis (MS) including immunosuppressants, immunomodulators, and monoclonal antibodies. Their relative effectiveness in the prevention of relapse or disability progression is unclear due to the limited number of direct comparison trials. A summary of the results, including both direct and indirect comparisons of treatment effects, may help to clarify the above uncertainty.

OBJECTIVES

To estimate the relative efficacy and acceptability of interferon ß-1b (IFNß-1b) (Betaseron), interferon ß-1a (IFNß-1a) (Rebif and Avonex), glatiramer acetate, natalizumab, mitoxantrone, methotrexate, cyclophosphamide, azathioprine, intravenous immunoglobulins, and long-term corticosteroids versus placebo or another active agent in participants with MS and to provide a ranking of the treatments according to their effectiveness and risk-benefit balance.

SEARCH METHODS

We searched the Cochrane Database of Systematic Reviews, the Cochrane MS Group Trials Register, and the Food and Drug Administration (FDA) reports. The most recent search was run in February 2012.

SELECTION CRITERIA

Randomized controlled trials (RCTs) that studied one of the 11 treatments for use in adults with MS and that reported our pre-specified efficacy outcomes were considered for inclusion.

DATA COLLECTION AND ANALYSIS

Identifying search results and data extraction were performed independently by two authors. Data synthesis was performed by pairwise meta-analysis and network meta-analysis that was performed within a Bayesian framework. The body of evidence for outcomes within the pairwise meta-analysis was assessed according to GRADE, as very low, low, moderate, or high quality.

MAIN RESULTS

Forty-four trials were included in this review, in which 17,401 participants had been randomised. Twenty-three trials included relapsing-remitting MS (RRMS) (9096 participants, 52%), 18 trials included progressive MS (7726, 44%), and three trials included both RRMS and progressive MS (579, 3%). The majority of the included trials were short-term studies, with the median duration being 24 months. The results originated mostly from 33 trials on IFNß, glatiramer acetate, and natalizumab that overall contributed outcome data for 9881 participants (66%).From the pairwise meta-analysis, there was high quality evidence that natalizumab and IFNß-1a (Rebif) were effective against recurrence of relapses in RRMS during the first 24 months of treatment compared to placebo (odds ratio (OR) 0.32, 95% confidence interval (CI) 0.24 to 0.43; OR 0.45, 95% CI 0.28 to 0.71, respectively); they were more effective than IFNß-1a (Avonex) (OR 0.28, 95% CI 0.22 to 0.36; OR 0.19, 95% CI 0.06 to 0.60, respectively). IFNß-1b (Betaseron) and mitoxantrone probably decreased the odds of the participants with RRMS having clinical relapses compared to placebo (OR 0.55, 95% CI 0.31 to 0.99; OR 0.15, 95% CI 0.04 to 0.54, respectively) but the quality of evidence for these treatments was graded as moderate. From the network meta-analysis, the most effective drug appeared to be natalizumab (median OR versus placebo 0.29, 95% credible intervals (CrI) 0.17 to 0.51), followed by IFNß-1a (Rebif) (median OR versus placebo 0.44, 95% CrI 0.24 to 0.70), mitoxantrone (median OR versus placebo 0.43, 95% CrI 0.20 to 0.87), glatiramer acetate (median OR versus placebo 0.48, 95% CrI 0.38 to 0.75), IFNß-1b (Betaseron) (median OR versus placebo 0.48, 95% CrI 0.29 to 0.78). However, our confidence was moderate for direct comparison of mitoxantrone and IFNB-1b vs placebo and very low for direct comparison of glatiramer vs placebo. The relapse outcome for RRMS at three years' follow-up was not reported by any of the included trials.Disability progression was based on surrogate markers in the majority of included studies and was unavailable for RRMS beyond two to three years. The pairwise meta-analysis suggested, with moderate quality evidence, that natalizumab and IFNß-1a (Rebif) probably decreased the odds of the participants with RRMS having disability progression at two years' follow-up, with an absolute reduction of 14% and 10%, respectively, compared to placebo. Natalizumab and IFNß-1b (Betaseron) were significantly more effective (OR 0.62, 95% CI 0.49 to 0.78; OR 0.35, 95% CI 0.17 to 0.70, respectively) than IFNß-1a (Avonex) in reducing the number of the participants with RRMS who had progression at two years' follow-up, and confidence in this result was graded as moderate. From the network meta-analyses, mitoxantrone appeared to be the most effective agent in decreasing the odds of the participants with RRMS having progression at two years' follow-up, but our confidence was very low for direct comparison of mitoxantrone vs placebo. Both pairwise and network meta-analysis revealed that none of the individual agents included in this review were effective in preventing disability progression over two or three years in patients with progressive MS.There was not a dose-effect relationship for any of the included treatments with the exception of mitoxantrone.

AUTHORS' CONCLUSIONS

Our review should provide some guidance to clinicians and patients. On the basis of high quality evidence, natalizumab and IFNß-1a (Rebif) are superior to all other treatments for preventing clinical relapses in RRMS in the short-term (24 months) compared to placebo. Moderate quality evidence supports a protective effect of natalizumab and IFNß-1a (Rebif) against disability progression in RRMS in the short-term compared to placebo. These treatments are associated with long-term serious adverse events and their benefit-risk balance might be unfavourable. IFNß-1b (Betaseron) and mitoxantrone probably decreased the odds of the participants with RRMS having relapses, compared with placebo (moderate quality of evidence). The benefit-risk balance with azathioprine is uncertain, however this agent might be effective in decreasing the odds of the participants with RRMS having relapses and disability progression over 24 to 36 months, compared with placebo. The lack of convincing efficacy data shows that IFNß-1a (Avonex), intravenous immunoglobulins, cyclophosphamide and long-term steroids have an unfavourable benefit-risk balance in RRMS. None of the included treatments are effective in decreasing disability progression in patients with progressive MS. It is important to consider that the clinical effects of all these treatments beyond two years are uncertain, a relevant point for a disease of 30 to 40 years duration. Direct head-to-head comparison(s) between natalizumab and IFNß-1a (Rebif) or between azathioprine and IFNß-1a (Rebif) should be top priority on the research agenda and follow-up of the trial cohorts should be mandatory.

[Interferon-β1b in multiple sclerosis therapy: more than 20 years clinical experience]

The introduction of interferon-β1b in 1993 in the USA and 2 years later in Europe made it possible for the first time to alter the course of the disease in patients with relapsing-remitting multiple sclerosis (MS). Subsequently, interferon-β1b was approved for the treatment of patients with active secondary progressive MS (1999) and early relapsing-remitting MS following a first demyelinating event (clinically isolated syndrome, CIS) (2006). Here we provide an overview of the clinical experience gathered during more than 20 years of interferon-β use focusing on long-term efficacy and safety and the impact of early initiation of treatment. Furthermore, the following aspects will be discussed: putative mechanisms of action of interferon-β, indications for a disease-modifying therapy, clinical relevance of neutralizing antibodies, importance of adherence in MS therapy, high versus low frequency therapy, combination therapies with interferon-β and safety of interferon-β in children and adolescents with MS and during pregnancy.

Improved MRI quantification of spinal cord atrophy in multiple sclerosis

PURPOSE

To identify an improved method for measuring spinal cord cross-sectional area (CSA) using magnetic resonance imaging (MRI) in multiple sclerosis (MS).

MATERIALS AND METHODS

MRI was performed on 15 controls and 15 MS patients and repeated in nine controls and nine patients after 6 months. At this timepoint, an additional scan was acquired to evaluate scan-rescan reproducibility. Two sequences were acquired in the cervical cord: 3D phase sensitive inversion recovery (PSIR) and 3D magnetization prepared rapid acquisition T1-weighted gradient echo. CSA was outlined at C2-C3 using two methods: a semiautomated edge detection method and active surface model (ASM). We evaluated reproducibility for all combinations of sequences and analysis methods using coefficient of variation (COV) and intraclass correlation coefficient and performed sample size calculations for clinical trials to reduce longitudinal cord atrophy.

RESULTS

PSIR/ASM combination provided the lowest values of COV for intrarater, interrater, scan-rescan reproducibility (0.002%, 0.03%, and 0.1% respectively). At 6-month follow-up no significant changes were seen in CSA of controls, and a trend towards significance was observed in patients.

CONCLUSION

PSIR/ASM proved more reproducible than established methods of evaluating CSA in MS and also provides the lowest number of subjects per arm for 6-month and 1-year clinical trials.

Targeting ASIC1 in primary progressive multiple sclerosis: evidence of neuroprotection with amiloride

Neurodegeneration is the main cause for permanent disability in multiple sclerosis. The effect of current immunomodulatory treatments on neurodegeneration is insufficient. Therefore, direct neuroprotection and myeloprotection remain an important therapeutic goal. Targeting acid-sensing ion channel 1 (encoded by the ASIC1 gene), which contributes to the excessive intracellular accumulation of injurious Na(+) and Ca(2+) and is over-expressed in acute multiple sclerosis lesions, appears to be a viable strategy to limit cellular injury that is the substrate of neurodegeneration. While blockade of ASIC1 through amiloride, a potassium sparing diuretic that is currently licensed for hypertension and congestive cardiac failure, showed neuroprotective and myeloprotective effects in experimental models of multiple sclerosis, this strategy remains untested in patients with multiple sclerosis. In this translational study, we tested the neuroprotective effects of amiloride in patients with primary progressive multiple sclerosis. First, we assessed ASIC1 expression in chronic brain lesions from post-mortem of patients with progressive multiple sclerosis to identify the target process for neuroprotection. Second, we tested the neuroprotective effect of amiloride in a cohort of 14 patients with primary progressive multiple sclerosis using magnetic resonance imaging markers of neurodegeneration as outcome measures of neuroprotection. Patients with primary progressive multiple sclerosis underwent serial magnetic resonance imaging scans before (pretreatment phase) and during (treatment phase) amiloride treatment for a period of 3 years. Whole-brain volume and tissue integrity were measured with high-resolution T(1)-weighted and diffusion tensor imaging. In chronic brain lesions of patients with progressive multiple sclerosis, we demonstrate an increased expression of ASIC1 in axons and an association with injury markers within chronic inactive lesions. In patients with primary progressive multiple sclerosis, we observed a significant reduction in normalized annual rate of whole-brain volume during the treatment phase, compared with the pretreatment phase (P = 0.018, corrected). Consistent with this reduction, we showed that changes in diffusion indices of tissue damage within major clinically relevant white matter (corpus callosum and corticospinal tract) and deep grey matter (thalamus) structures were significantly reduced during the treatment phase (P = 0.02, corrected). Our results extend evidence of the contribution of ASIC1 to neurodegeneration in multiple sclerosis and suggest that amiloride may exert neuroprotective effects in patients with progressive multiple sclerosis. This pilot study is the first translational study on neuroprotection targeting ASIC1 and supports future randomized controlled trials measuring neuroprotection with amiloride in patients with multiple sclerosis.

Cutaneous adverse events associated with disease-modifying treatment in multiple sclerosis: a systematic review

Glatiramer acetate and interferon-beta are approved first-line disease-modifying treatments (DMTs) for multiple sclerosis (MS). DMTs can be associated with cutaneous adverse events, which may influence treatment adherence and patient quality of life. In this systematic review, we aimed to provide an overview of the clinical spectrum and the incidence of skin reactions associated with DMTs. A systematic literature search was performed up to May 2011 in Medline, Embase, and Cochrane databases without applying restrictions in study design, language, or publishing date. Eligible for inclusion were articles describing any skin reaction related to DMTs in MS patients. Selection of articles and data extraction were performed by two authors independently. One hundred and six articles were included, of which 41 (39%) were randomized controlled trials or cohort studies reporting incidences of mainly local injection-site reactions. A large number of patients had experienced some form of localized injection-site reaction: up to 90% for those using subcutaneous formulations and up to 33% for those using an intramuscular formulation. Sixty-five case-reports involving 106 MS patients described a wide spectrum of cutaneous adverse events, the most frequently reported being lipoatrophy, cutaneous necrosis and ulcers, and various immune-mediated inflammatory skin diseases. DMTs for MS are frequently associated with local injection-site reactions and a wide spectrum of generalized cutaneous adverse events, in particular, the subcutaneous formulations. Although some of the skin reactions may be severe and persistent, most of them are mild and do not require cessation of DMT.

Interferon beta for secondary progressive multiple sclerosis

BACKGROUND

Therapy with either recombinant beta-1a or beta-1b interferons (IFNs) is worldwide approved for Relapsing Remitting Multiple Sclerosis (RRMS). A major unanswered question is whether this treatment is able to safely reverse or retard the progressive phase of the disease.

OBJECTIVES

The main objective was to verify whether IFNs treatment in Secondary Progressive Multiple Sclerosis (SPMS) is more effective than placebo in reducing the number of patients who experience disability progression.

SEARCH METHODS

We searched the Cochrane Multiple Sclerosis Group's Trials Register (1995 to 15 February 2011), the reference lists of relevant articles and conference proceedings. Regulatory agencies were used as additional sources of information.

SELECTION CRITERIA

We included all randomised, double or single blind, placebo-controlled trials (RCTs) evaluating the efficacy of IFNs versus placebo in SPMS patients.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed all reports retrieved from the search. They independently extracted clinical, safety and MRI data, using a predefined data extraction form, resolving disagreements after discussion with a third reviewer. Risk of bias was evaluated to assess the quality of the studies. Treatment effect was measured using Risk Ratio (RR) with 95% confidence intervals (CI) for the binary outcomes and Standard Mean Difference with 95% CI for the continuous outcomes.

MAIN RESULTS

Five RCTs met the inclusion criteria, from which 3122 (1829 IFN and 1293 placebo) treated patients contributed to the analysis. Included population was heterogeneous in terms of baseline clinical characteristics of the disease, in particular the percentage of patients affected by secondary progression with superimposed relapse ranging from 72% to 44%. IFN beta 1a and 1b did not decrease the risk of progression sustained at 6 months (RR, 95% CI: 0.98, [0.82-1.16]) after three years of treatment. A significant decrease of the risk of progression sustained at 3 months (RR, 95% CI: 0.88 [0.80, 0.97]) and of the risk of developing new relapses at three years (RR 0.91, [0.84-0.97]) were found. The risk of developing new active brain lesions decreased over time but this data was obtained from single studies on Magnetic Resonance Imaging (MRI), performed in subgroups of patients; in spite of no effect on progression, the radiological data supported an effect on MRI parameters. The safety profile reflects what is commonly reported in MS IFN-treated patients.

AUTHORS' CONCLUSIONS

Well designed RCTs, evaluating a high number of patients were included in the review. Recombinant IFN beta does not prevent the development of permanent physical disability in SPMS. We were unable to verify the effect on cognitive function for the lack of comparable data. This treatment significantly reduces the risk of relapse and of short -term relapse-related disability.Overall, these results show that IFNs' anti-inflammatory effect is unable to retard progression, when established. In the future, no new RCTs for IFNs versus placebo in SPMS will probably be undertaken, because research is now focusing on innovative drugs. We believe that this review gives conclusive evidence on the clinical efficacy of IFNs versus placebo in SPMS.

Targeting progressive neuroaxonal injury: lessons from multiple sclerosis

Neurodegenerative diseases, such as Alzheimer's disease (AD), Parkinson's disease (PD) and amyotrophic lateral sclerosis (ALS), are characterized by progressive neuroaxonal injury, suggesting a common pathophysiological pathway. Identification and development of neuroprotective therapies for such diseases has proven a major challenge, particularly because of an already substantial neuroaxonal compromise at the time of initial onset of clinical symptoms. Methods for early identification of neurodegeneration are therefore vital to ensure that neuroprotective therapies are applied as early as possible. Recent investigations have enhanced our understanding of the role of neuroaxonal injury in multiple sclerosis (MS). As MS generally manifests earlier in life and can be diagnosed much earlier in the course of the disease than the above-mentioned 'classic' neurodegenerative diseases, it is possible that MS could be used as a model disease to study degeneration and regeneration of the CNS. The mechanism of neuroaxonal injury in MS is believed to be inflammation-led neurodegeneration; however, the reverse may also be true (i.e. neuroaxonal degeneration may precede inflammation). Animal models of PD, AD and ALS have shown that it is likely that most cases of disease are due to initial inflammation, followed by a degenerative process, providing a parallel between MS and the classic neurodegenerative diseases. Other common factors between MS and the neurodegenerative diseases include iron and mitochondrial dysregulation, abnormalities in α-synuclein and tau protein, and a number of immune mediators. Conventional MRI techniques, using markers such as T2-weighted lesions, gadolinium-enhancing lesions and T1-weighted hypointensities, are readily available and routinely used in clinical practice; however, the utility of these MRI measures to predict disease progression in MS is limited. More recently, MRI techniques that provide more pathology-specific data have been applied in MS studies, including magnetic resonance spectroscopy, magnetization transfer ratio and myelin water imaging. Optical coherence tomography (OCT) is a non-MRI technique that quantifies optic nerve integrity and retinal ganglion cell loss as markers of neuroaxonal injury; more research is needed to evaluate whether information obtained from OCT is a reliable marker of axonal injury and long-term disability in MS. Using these advanced techniques, it may become possible to follow degeneration and regeneration longitudinally in patients with MS and to better differentiate the effects of drugs under investigation. Currently available immune-directed therapies that are approved by the US FDA for the first-line treatment of MS (interferon-β and glatiramer acetate) have been shown to decelerate the inflammatory process in MS; however, such therapy is less effective in preventing the progression of the disease and neuroaxonal injury. The use of MS as a clinical model to study modulation of neuroaxonal injury in the brain could have direct implications for the development of treatment strategies in neurodegenerative diseases such as AD, PD and ALS.

Chronic progressive multiple sclerosis - pathogenesis of neurodegeneration and therapeutic strategies

Multiple sclerosis (MS) is an inflammatory, autoimmune, demyelinating disease of the central nervous system (CNS) that usually starts as a relapsing-remitting disease. In most patients the disease evolves into a chronic progressive phase characterized by continuous accumulation of neurological deficits. While treatment of relapsing-remitting MS (RRMS) has improved dramatically over the last decade, the therapeutic options for chronic progressive MS, both primary and secondary, are still limited. In order to find new pharmacological targets for the treatment of chronic progressive MS, the mechanisms of the underlying neurodegenerative process that becomes apparent as the disease progresses need to be elucidated. New animal models with prominent and widespread progressive degenerative components of MS have to be established to study both inflammatory and non-inflammatory mechanisms of neurodegeneration. Here, we discuss disease mechanisms and treatment strategies for chronic progressive MS.

T2 lesion location really matters: a 10 year follow-up study in primary progressive multiple sclerosis

OBJECTIVES

Prediction of long term clinical outcome in patients with primary progressive multiple sclerosis (PPMS) using imaging has important clinical implications, but remains challenging. We aimed to determine whether spatial location of T2 and T1 brain lesions predicts clinical progression during a 10-year follow-up in PPMS.

METHODS

Lesion probability maps of the T2 and T1 brain lesions were generated using the baseline scans of 80 patients with PPMS who were clinically assessed at baseline and then after 1, 2, 5 and 10 years. For each patient, the time (in years) taken before bilateral support was required to walk (time to event (TTE)) was used as a measure of progression rate. The probability of each voxel being 'lesional' was correlated with TTE, adjusting for age, gender, disease duration, centre and spinal cord cross sectional area, using a multiple linear regression model. To identify the best, independent predictor of progression, a Cox regression model was used.

RESULTS

A significant correlation between a shorter TTE and a higher probability of a voxel being lesional on T2 scans was found in the bilateral corticospinal tract and superior longitudinal fasciculus, and in the right inferior fronto-occipital fasciculus (p<0.05). The best predictor of progression rate was the T2 lesion load measured along the right inferior fronto-occipital fasciculus (p=0.016, hazard ratio 1.00652, 95% CI 1.00121 to 1.01186).

CONCLUSION

Our results suggest that the location of T2 brain lesions in the motor and associative tracts is an important contributor to the progression of disability in PPMS, and is independent of spinal cord involvement.