Meta-analysis of the placebo-treated groups in clinical trials of progressive MS

Brain grey matter perfusion in primary progressive multiple sclerosis: Mild decrease over years and regional associations with cognition and hand function

BACKGROUND

Extend and dynamic of neurodegeneration in progressive Multiple Sclerosis (MS) might be reflected by global and regional brain perfusion, an outcome at the intercept between structure and function. Here, we provide a first insight in the evolution of brain perfusion and its association with disability in primary progressive MS (PPMS) over several years.

METHODS

77 persons with PPMS were followed over up to 5 years. Visits included a 3T MRI with pulsed Arterial spin labelling (ASL) perfusion, the Timed-25-Foot-Walk, 9-Hole-Peg-Test (NHPT), Symbol-Digit-Modalities-Test (SDMT) and Expanded Disability Status Scale (EDSS). We extracted regional cerebral blood flow surrogates and compared them to 11 controls. Analyses focused in cortical and deep gray matter, the change over time and associations with disability on regional and global level.

RESULTS

Baseline brain perfusion of patients and controls was comparable for the cortex (p=0.716) and deep grey matter (p=0.095). EDSS disability increased mildly (p=0.023) while brain perfusion decreased during follow up (p<0.001) and with disease duration (p=0.009). Lower global perfusion correlated with higher disability as indicated by EDSS, NHPT and Timed-25-Foot-Walk (p<0.001). The motor task NHPT showed associations with twenty gray matter regions. In contrast, better SDMT performance correlated with lower perfusion (p<0.001) in seven predominantly frontal regions indicating a functional maladaptation.

CONCLUSION

Decreasing perfusion indicates a putative association with MS disease mechanisms such as neurodegeneration, reduced metabolism, and loss of resilience. A low alteration rate limits its use in clinical practice, but regional association patterns might provide a snapshot of adaptive and maladaptive functional reorganization.

Early predictors of conversion to secondary progressive multiple sclerosis

BACKGROUND

We conducted this study to estimated the time of conversion from relapsing-remitting MS (RRMS) to SPMS and its early predictor factors.

METHODS

In this retrospective study, demographic, clinical, and imaging data from MS patients at diagnosis were extracted. Cox proportional hazards model was used to assess the association between various baseline characteristics and conversion to SPMS. We also assessed the association brtween escalation and early intensive therapy approaches with transition to progressive phase.

RESULTS

Out of 1903 patients with RRMS at baseline, 293 (15.4%) patients progressed to SPMS during follow-up. The estimated number of patients converted to SPMS was 10% at 10-years, 50% at 20-years, and 93% at 30-years. On multivariate Cox regression analysis older age at onset (HR: 1.067, 95%CI: 1.048-1.085, p < 0.001), smoking (HR: 2.120, 95%CI: 1.203-3.736, p = 0.009), higher EDSS at onset (HR: 1.199, 95%CI: 1.109-1.295, p < 0.001), motor dysfunction (HR: 2.470, 95%CI: 1.605-3.800, p < 0.001), cerebellar dysfunction (HR: 3.096, 95%CI: 1.840-5.211, p < 0.001), and presence of lesions in spinal cord (HR: 0.573, 95%CI: 0.297-0.989, p = 0.042) increased the risk of conversion from RRMS to SPMS. No significant difference between escalation and EIT groups in the risk of transition to progressive phase (weighted HR = 1.438; 95% CI: 0.963, 2.147; p = 0.076) was found.

CONCLUSION

Our data support previous observations that smoking is a modifiable risk factor for secondary progressive MS and confirms that spinal cord involvement, age, and more severe disease at onset are prognostic factors for converting to secondary progressive MS.

Deciphering Multiple Sclerosis Progression

Multiple sclerosis (MS) is primarily an inflammatory and degenerative disease of the central nervous system, triggered by unknown environmental factors in patients with predisposing genetic risk profiles. The prevention of neurological disability is one of the essential goals to be achieved in a patient with MS. However, the pathogenic mechanisms driving the progressive phase of the disease remain unknown. It was described that the pathophysiological mechanisms associated with disease progression are present from disease onset. In daily practice, there is a lack of clinical, radiological, or biological markers that favor an early detection of the disease's progression. Different definitions of disability progression were used in clinical trials. According to the most descriptive, progression was defined as a minimum increase in the Expanded Disability Status Scale (EDSS) of 1.5, 1.0, or 0.5 from a baseline level of 0, 1.0–5.0, and 5.5, respectively. Nevertheless, the EDSS is not the most sensitive scale to assess progression, and there is no consensus regarding any specific diagnostic criteria for disability progression. This review document discusses the current pathophysiological concepts associated with MS progression, the different measurement strategies, the biomarkers associated with disability progression, and the available pharmacologic therapeutic approaches.

Structural and Clinical Correlates of a Periventricular Gradient of Neuroinflammation in Multiple Sclerosis

Objectives

To explore in vivo innate immune cell activation as a function of the distance from ventricular CSF in patients with multiple sclerosis (MS) using [¹⁸F]-DPA714 PET and to investigate its relationship with periventricular microstructural damage, evaluated by magnetization transfer ratio (MTR), and with trajectories of disability worsening.

Methods

Thirty-seven patients with MS and 19 healthy controls underwent MRI and [¹⁸F]-DPA714 TSPO dynamic PET, from which individual maps of voxels characterized by innate immune cell activation (DPA+) were generated. White matter (WM) was divided in 3-mm-thick concentric rings radiating from the ventricular surface toward the cortex, and the percentage of DPA+ voxels and mean MTR were extracted from each ring. Two-year trajectories of disability worsening were collected to identify patients with and without recent disability worsening.

Results

The percentage of DPA+ voxels was higher in patients compared to controls in the periventricular WM (p = 6.10e-6) and declined with increasing distance from ventricular surface, with a steeper gradient in patients compared to controls (p = 0.001). This gradient was found in both periventricular lesions and normal-appearing WM. In the total WM, it correlated with a gradient of microstructural tissue damage measured by MTR (r_s = −0.65, p = 1.0e-3). Compared to clinically stable patients, patients with disability worsening were characterized by a higher percentage of DPA+ voxels in the periventricular normal-appearing WM (p = 0.025).

Conclusions

Our results demonstrate that in MS the innate immune cell activation predominates in periventricular regions and is associated with microstructural damage and disability worsening. This could result from the diffusion of proinflammatory CSF-derived factors into surrounding tissues.

Individual Mapping of Innate Immune Cell Activation Is a Candidate Marker of Patient-Specific Trajectories of Worsening Disability in Multiple Sclerosis

Our objective was to develop a novel approach to generate individual maps of white matter (WM) innate immune cell activation using ¹⁸F-DPA-714 translocator protein PET and to explore the relationship between these maps and individual trajectories of worsening disability in patients with multiple sclerosis (MS). Methods: Patients with MS (n = 37), whose trajectories of worsening disability over the 2 y preceding study entry were calculated, and healthy controls (n = 19) underwent MRI and ¹⁸F-DPA-714 PET. A threshold for significant activation of ¹⁸F-DPA-714 binding was calculated with a voxelwise randomized permutation-based comparison between patients and controls and used to classify each WM voxel in all subjects as characterized by a significant activation of innate immune cells (DPA+) or not. Individual maps of innate immune cell activation in the WM were used to calculate the extent of activation in WM regions of interests and to classify each WM lesion as DPA-active, DPA-inactive, or unclassified. Results: Compared with the WM of healthy controls, patients with MS had a significantly higher percentage of DPA+ voxels in the normal-appearing WM (NAWM) (NAWM in patients, 24.6% ± 1.4%; WM in controls, 14.6% ± 2.0%; P < 0.001). In patients with MS, the percentage of DPA+ voxels increased significantly from the NAWM to the perilesional areas, T2 hyperintense lesions, and T1 hypointense lesions (38.1% ± 2.6%, 45.0% ± 2.6%, 51.8% ± 2.6%, respectively; P < 0.001). Among the 1,379 T2 lesions identified, 512 were defined as DPA-active and 258 as DPA-inactive. A higher number of lesions classified as DPA-active (odds ratio, 1.13; P = 0.009), a higher percentage of DPA+ voxels in the NAWM (odds ratio, 1.16; P = 0.009), and a higher percentage of DPA+ voxels in T1 spin-echo lesions (odds ratio, 1.06; P = 0.036) were significantly associated with a retrospectively more severe clinical trajectory in patients with MS. Conclusion: A more severe trajectory of disability worsening in MS is associated with innate immune cell activation inside and around WM lesions. ¹⁸F-DPA-714 PET may provide a promising biomarker to identify patients at risk of a severe clinical trajectory.

ESIMS - An Ongoing Clinical Trial in Secondary Progressive Multiple Sclerosis

The design of a double-blind, placebo-controlled, European-Canadian Study on IVIG treatment in multiple sclerosis-ESIMS- is described. Three hundred and eighteen multiple sclerosis patients with a secondary progressive course, are treated with monthly infusions of immunoglobulin 10% I g/kg bodyweight or with 0.1 g albumin/vial for 27 months. The primary efficacy parameter is the percentage of patients with a confirmed treatment failure in the EDSS scale and/or the Nine Hole Peg Test Secondary outcome measures are MRI T2 lesion load, Magnetization Transfer Imaging, and MRI brainatrophy measures. Documentation of health resource utilisation and ability to work will cover socio-economic aspects. Recruitment of patients was completed in October 1998. The clinical part of the trial will be completed in April 2001.

Optical coherence tomography segmentation analysis in relapsing remitting versus progressive multiple sclerosis

Introduction

Optical coherence tomography (OCT) with retinal segmentation analysis is a valuable tool in assessing axonal loss and neuro-degeneration in multiple sclerosis (MS) by in-vivo imaging, delineation and quantification of retinal layers. There is evidence of deep retinal involvement in MS beyond the inner retinal layers. The ultra-structural retinal changes in MS in different MS phenotypes can reflect differences in the pathophysiologic mechanisms. There is limited data on the pattern of deeper retinal layer involvement in progressive MS (PMS) versus relapsing remitting MS (RRMS). We have compared the OCT segmentation analysis in patients with relapsing-remitting MS and progressive MS.

Methods

Cross-sectional study of 113 MS patients (226 eyes) (29 PMS, 84 RRMS) and 38 healthy controls (72 eyes). Spectral domain OCT (SDOCT) using the macular cube acquisition protocol (Cirrus HDOCT 5000; Carl Zeiss Meditec) and segmentation of the retinal layers for quantifying the thicknesses of the retinal layers. Segmentation of the retinal layers was carried out utilizing Orion software (Voxeleron, USA) for quantifying the thicknesses of individual retinal layers.

Results

The retinal nerve finer layer (RNFL) (p = 0.023), the ganglion-cell/inner plexiform layer (GCIPL) (p = 0.006) and the outer plexiform layer (OPL) (p = 0.033) were significantly thinner in PMS compared to RRMS. There was significant negative correlation between the outer nuclear layer (ONL) and EDSS (r = -0.554, p = 0.02) in PMS patients. In RRMS patients with prior optic neuritis, the GCIPL correlated negatively (r = -0.317; p = 0.046), while the photoreceptor layer (PR) correlated positively with EDSS (r = 0.478; p = 0.003).

Conclusions

Patients with PMS exhibit more atrophy of both the inner and outer retinal layers than RRMS. The ONL in PMS and the GCIPL and PR in RRMS can serve as potential surrogate of disease burden and progression (EDSS). The specific retinal layer predilection and its correlation with disability may reflect different pathophysiologic mechanisms and various stages of progression in MS.

Defining secondary progressive multiple sclerosis

A number of studies have been conducted with the onset of secondary progressive multiple sclerosis as an inclusion criterion or an outcome of interest. However, a standardized objective definition of secondary progressive multiple sclerosis has been lacking. The aim of this work was to evaluate the accuracy and feasibility of an objective definition for secondary progressive multiple sclerosis, to enable comparability of future research studies. Using MSBase, a large, prospectively acquired, global cohort study, we analysed the accuracy of 576 data-derived onset definitions for secondary progressive multiple sclerosis and first compared these to a consensus opinion of three neurologists. All definitions were then evaluated against 5-year disease outcomes post-assignment of secondary progressive multiple sclerosis: sustained disability, subsequent sustained progression, positive disability trajectory, and accumulation of severe disability. The five best performing definitions were further investigated for their timeliness and overall disability burden. A total of 17 356 patients were analysed. The best definition included a 3-strata progression magnitude in the absence of a relapse, confirmed after 3 months within the leading Functional System and required an Expanded Disability Status Scale step ≥4 and pyramidal score ≥2. It reached an accuracy of 87% compared to the consensus diagnosis. Seventy-eight per cent of the identified patients showed a positive disability trajectory and 70% reached significant disability after 5 years. The time until half of all patients were diagnosed was 32.6 years (95% confidence interval 32-33.6) after disease onset compared with the physicians' diagnosis at 36 (35-39) years. The identified patients experienced a greater disease burden [median annualized area under the disability-time curve 4.7 (quartiles 3.6, 6.0)] versus non-progressive patients [1.8 (1.2, 1.9)]. This objective definition of secondary progressive multiple sclerosis based on the Expanded Disability Status Scale and information about preceding relapses provides a tool for a reproducible, accurate and timely diagnosis that requires a very short confirmation period. If applied broadly, the definition has the potential to strengthen the design and improve comparability of clinical trials and observational studies in secondary progressive multiple sclerosis.

How similar are commonly combined criteria for EDSS progression in multiple sclerosis?

Introduction Measuring disease progression is an important aspect of multiple sclerosis (MS) clinical trials. Commonly applied disability endpoints include time to clinically meaningful Expanded Disability Status Scale (EDSS) change, or the number of patients in whom such a change has occurred. Typically, clinically meaningful EDSS change has been defined as a change of 1.0 point on Kurtzke’s EDSS in patients with an entry EDSS score of 5.5 or lower, or 0.5 point in patients with a higher EDSS score. Our goal was to evaluate whether these changes can be considered as similar. Therefore, we compared EDSS changes to corresponding changes in the Guy’s Neurological Disability Scale (GNDS), which is a measure of patient perceived disability, and the Multiple Sclerosis Functional Composite (MSFC), which is an examination-based quantitative scoring of neurological impairment.

Methods From a large longitudinal database, we selected two groups of patients with a clinically meaningful change in EDSS score according to the usual criteria: patients with EDSS change]/1.0 for baseline EDSS 5/5.5 and patients with EDSS change]/0.5 for baseline EDSS]/6.0. We compared changes in GNDS sum score and in MSFC score between both groups.

Results In the group with baseline EDSS]/6.0, GNDS and MSFC changes were higher than in patients with baseline EDSS 5/5.5. The difference in change was 1.00 (95% confidence interval (CI): / 0.35 to 2.36) for the GNDS and 0.412 (95% CI: 0.300-0.525) for the MSFC.

Conclusion Our results indicate that a 0.5 point EDSS change in patients with baseline EDSS / 6.0 cannot be considered equal to a 1.0 point change in patients with baseline EDSS 5/5.5.

Defining reliable disability outcomes in multiple sclerosis

Prevention of irreversible disability is currently the most important goal of disease modifying therapy for multiple sclerosis. The disability outcomes used in most clinical trials rely on progression of Expanded Disability Status Scale score confirmed over 3 or 6 months. However, sensitivity and stability of this metric has not been extensively evaluated. Using the global MSBase cohort study, we evaluated 48 criteria of disability progression, testing three definitions of baseline disability, two definitions of progression magnitude, two definitions of long-term irreversibility and four definitions of event confirmation period. The study outcomes comprised the rates of detected progression events per 10 years and the proportions of the recorded events persistent at later time points. To evaluate the ratio of progression frequency and stability for each criterion, we calculated the proportion of events persistent over the five subsequent years once progression was achieved. Finally, we evaluated the clinical and demographic determinants characterising progression events and, for those that regressed back to baseline, determinants of their subsequent regression. The study population consisted of 16 636 patients with the minimum of three recorded disability scores, totalling 112 584 patient-years. The progression rates varied between 0.41 and 1.14 events per 10 years, with the length of required confirmation interval as the most important determinant of the observed variance. The concordance among all tested progression criteria was only 17.3%. Regression of disability occurred in 11-34% of the progression events over the five subsequent years. The most important determinant of progression stability was the length of the confirmation period. For the most accurate set of the progression criteria, the proportions of 3-, 6-, 12- or 24-month confirmed events persistent over 5 years reached 70%, 74%, 80% and 89%, respectively. Regression post progression was more common in younger patients, relapsing-remitting disease course, and after a smaller change in disability, and was inflated by higher visit frequency. These results suggest that the disability outcomes based on 3-6-month confirmed disability progression overestimate the accumulation of permanent disability by up to 30%. This could lead to spurious results in short-term clinical trials, and the issue may be magnified further in cohorts consisting predominantly of younger patients and patients with relapsing-remitting disease. Extension of the required confirmation period increases the persistence of progression events.

Regression to the mean and predictors of MRI disease activity in RRMS placebo cohorts--is there a place for baseline-to-treatment studies in MS?

Background

Gadolinium-enhancing (GD+) lesions and T2 lesions are MRI outcomes for phase-2 treatment trials in relapsing-remitting Multiple Sclerosis (RRMS). Little is known about predictors of lesion development and regression-to-the-mean, which is an important aspect in early baseline-to-treatment trials.

Objectives

To quantify regression-to-the-mean and identify predictors of MRI lesion development in placebo cohorts.

Methods

21 Phase-2 and Phase-3 trials were identified by a systematic literature research. Random-effects meta-analyses were performed to estimate development of T2 and GD+ after 6 months (phase-2) or 2 years (phase-3). Predictors of lesion development were evaluated with mixed-effect meta-regression.

Results

The mean number of GD+-lesions per scan was similar after 6 months (1.19, 95%CI: 0.87-1.51) and 2 years (1.19, 95%CI: 1.00-1.39). 39% of the patients were without new T2-lesion after 6 month and 19% after 2 years (95%CI: 12-25%). Mean number of baseline GD+-lesions was the best predictor for new lesions after 6 months.

Conclusion

Baseline GD-enhancing lesions predict evolution of Gd- and T2 lesions after 6 months and might be used to control for regression to the mean effects. Overall, proof-of-concept studies with a baseline to treatment design have to face a regression to 1.2 GD+lesions per scan within 6 months.

Clinical outcome measures in multiple sclerosis

Clinical outcome measures are indispensable when studying the natural course of multiple sclerosis (MS) and critical for determining the effect of an intervention. For these purposes clinical outcome measures should be valid, reliable, and responsive. Moreover they should assess clinically relevant aspects of the disease. Given the nature of the disease, outcome measures in MS should be able to capture multiple clinical dimensions. Long-term disability-free survival is the ultimate goal of MS treatment. Since the observation period in clinical trials is too short to get a final answer on that outcome, clinicians and researchers rely on extrapolation of the results beyond the treatment period. Yet the long-term predictive value of most outcome measures (e.g., relapse rate) used for short-term responses has not yet been determined. The expanded disability status scale (EDSS) is the outcome measure that is most often included in MS studies. The EDSS appeals to most neurologists as it is the result of a standardized neurologic examination and neurologists know it well. However, when considered critically, the EDSS has serious weaknesses from a clinimetric point of view that limit its value as an outcome measure in MS. The search for an alternative outcome measure that can fulfill all essential requirements and will be accepted by the scientific community, clinicians, and regulatory agencies is a huge challenge.

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.

A health-economic evaluation of disease-modifying drugs for the treatment of relapsing-remitting multiple sclerosis from the German societal perspective

OBJECTIVE

This analysis compared the cost-effectiveness of interferon beta-1a (IFNbeta-1a) 44 microg SC with that of other available first-line treatments for relapsing-remitting multiple sclerosis (RRMS) from the German societal perspective in 2008.

METHODS

A decision-analytic model was used to estimate the cost-effectiveness of IFNbeta-1a 44 microg SC given 3 times weekly compared with that of IFNbeta-la 30 microg IM given once weekly, IFNbeta-1b 8 mIU given every other day, and glatiramer acetate 20 mg SC given once daily. Data sources included the published literature, clinical trials, German price/tariff lists, and national population statistics. The time horizon of the model was 4 years, which was the maximum duration of follow-up in published clinical trials.

RESULTS

The cost-effectiveness (cost per relapse avoided) of IFNbeta-la 44 microg SC compared with no active treatment was euro51,250, which compared favorably with that of IFNbeta-la 30 microg IM (euro133,770), glatiramer acetate (euro71,416), and IFNbeta-1b (euro54,475). When the cost of disease progression was excluded, the cost per relapse avoided remained favorable for IFNbeta-1a 44 microg SC (euro54,292) compared with the other options (euro143,186, euro72,809, and euro56,816, respectively). Indirect comparison of each available treatment option with the next best alternative indicated that the incremental cost-effectiveness of IFNbeta-la 44 microg SC (euro23,449) was consistent with accepted thresholds. Sensitivity analyses in which the discount rate, frequency of relapse and disease progression, costs of relapse and disease progression, and adherence were varied did not affect the relative outcomes.

CONCLUSION

In this analysis from the German societal perspective, IFNbeta-la 44 microg SC had favorable overall cost-effectiveness versus no active treatment compared with other available disease-modifying drugs for the treatment of RRMS.

Clinical outcome measures in multiple sclerosis

Quantifying the clinical impact of multiple sclerosis (MS) is a critical issue for judging experimental therapies tested in clinical trials, and, in everyday practice, for optimizing individual patient care. Proposed clinical outcome measures for MS belong to four main categories. In the first, information is based on the objective neurological examination. Examples in this category include the Expanded Disability Status Scale and related instruments, the Scripps Neurological Rating Scale and the MS Impairment Scale. The second category is represented by quantitative tests of neurological function: the most important example is represented by the Multiple Sclerosis Functional Composite. In the third category, information is provided by the patient or a family member. Measures of disability and handicap (as the Incapacity Status Scale, and the Environmental Status Scale), and generic or disease-specific quality of life instruments are included in this class. Finally, the last category consists of measures which present hybrid characteristics, such as the Ambulation Index and the Cambridge Multiple Sclerosis Basic Score. To date, no single measure has emerged as the ideal outcome measure: the main advantages and disadvantages of currently available measurement tools are discussed.

Interferon beta in secondary progressive multiple sclerosis

BACKGROUND AND OBJECTIVE

Observational studies may provide additional information about the behaviour of different drugs in the post-marketing period. We present the data from a cohort of secondary progressive multiple sclerosis (SPMS) patients treated with interferon beta (IFNbeta-1b) at our MS clinic.

METHODS

This was an independent, open-label, non-randomised, observational study. Within the period 1998 to 2005, all patients with SPMS who started therapy with IFNbeta-1b at our centre were studied. Each patient was included in a follow-up protocol collecting demographic and baseline clinical data.

RESULTS

We studied 146 SPMS patients with a median follow-up of 60 months. Over the total study period, 62.2% of patients had confirmed progression. The analysis of the time to con- firmed progression showed that patients with two or more relapses in the 2 years before IFNbeta initiation, had a higher risk of disability increase than those patients with less than two relapses (p = 0.002). Multiple regression analysis showed disease activity in terms of relapses as the only factor to predict increase of disability during the follow-up period. A significant proportion of patients (36%) stopped treatment during the follow-up period. IFNbeta was safe, although some unexpected adverse events were observed.

CONCLUSIONS

A higher disease activity before the beginning of treatment with IFNbeta in SPMS patients with a given EDSS rank could identify those with faster disability progression after treatment initiation.

Regression to the mean in multiple sclerosis

In order to ensure sufficient disease activity, patients with relapsing remitting (RR) multiple sclerosis (MS) are often included in randomized placebo-controlled trials, only if they have a high baseline activity. These patients, whose evolution is unusual in the pre-study period, will tend to show a more usual behavior when followed up over a period of time. This phenomenon is known as regression to the mean. Regression to the mean should be taken into account in correctly interpreting long-term studies of cohorts treated without a placebo control group, which use the baseline period as control. The aim of this study was to evaluate the relevance of this phenomenon in a non-treated cohort of RRMS patients, selected with similar criteria to those used in randomized placebo-controlled clinical trials. Forty-four patients with definite RRMS, with two or more relapses in the previous two years, and a baseline EDSS < or = 5.5 were prospectively followed. The mean number of relapses spontaneously decreased from 1.72 (SD: 1.4) in the year prior to enrolment, to 1.0 (SD: 1.3) during the first year of follow-up (P < 0.05). Regression to the mean may explain as much as 40% of the reduction in the relapse rate from the baseline period to the period on-study.

Defining the response to interferon‐β in relapsing‐remitting multiple sclerosis patients

OBJECTIVE

Many patients with multiple sclerosis (MS) are currently receiving treatment with interferon (IFN)-beta. Early identification of nonresponder patients is crucial to try different therapeutic approaches. We investigated various criteria of treatment response to assess which criterion better identifies patients with a poor response.

METHODS

We studied relapsing-remitting MS (RRMS) patients treated with IFN-beta and followed them up for at least 2 years. Expanded Disability Status Score was scored every 3 months and relapses were recorded. We analyzed various criteria based on relapses, disability progression, or both.

RESULTS

Three hundred ninety-three patients were included. After 2 years of treatment, we observed a proportion of nonresponders, ranging from 7 to 49% depending on the stringency of the criteria used. Criteria based in disability progression had higher sensitivity, specificity, and accuracy. The hazard ratio for the development of marked disability after 6 years of treatment was 39.6 (95% confidence interval, 16.6-94.4) among the patients who fulfilled the criterion based only in disability progression.

INTERPRETATION

Criteria of response to IFN-beta therapy in RRMS using disability progression are more clinically relevant than those based only in relapse rate. This finding may be important for the counseling and care of RRMS patients treated with IFN-beta.

Aggressive multiple sclerosis—is there a role for stem cell transplantation?

Conventional drugs, including disease-modifying drugs, various cytostatic regimens and steroids, are unable to control disease activity in a small group of patients with "malignant" multiple sclerosis (MS). This group of patients could be offered aggressive therapies, such as high-dose immunosuppression followed by haematopoietic stem cell transplant (HSCT). Bone marrow or peripheral blood HSCT has been proposed for the treatment of autoimmune diseases because of its immunosuppressive and immunomodulatory effects, and recapitulation of lymphocyte ontogeny may stabilise or improve the course of MS in some patients. There have been a few small studies conducted using high-dose immunoablation and HSCT. A recent clinical trial of 85 patients treated by HSCT revealed that more than 60% of patients may benefit from this procedure. Due to the perceived risks associated with HSCT, only patients with malignant MS who no longer benefit from more conventional therapies were enrolled. HSCT is thus a justified and feasible treatment in certain patient groups, although transplant-related mortality must be reduced.

Intravenous immunoglobulin in secondary progressive multiple sclerosis: randomised placebo-controlled trial

BACKGROUND

Several double-blind placebo-controlled trials of relapsing-remitting multiple sclerosis have shown beneficial effects of intravenous immunoglobulin (IVIG) on relapse rate and disability. The European Study on Intravenous Immunoglobulin in Multiple Sclerosis set out to test IVIG in the secondary progressive phase of the disease.

METHODS

318 patients with clinically definite secondary progressive multiple sclerosis (mean age 44 years [SD 7]) were randomly assigned IVIG 1 g/kg per month (n=159) or an equivalent volume of placebo (albumin 0.1%; n=159) for 27 months. After baseline investigation, clinical assessments were made every 3 months and MRI was repeated after 12 months and 24 months. The primary outcome was confirmed worsening of disability as defined by the time to first confirmed progression on the expanded disability status scale (EDSS). Analyses were by intention to treat.

FINDINGS

19 patients in the IVIG group and 39 in the placebo group terminated study treatment prematurely but were included in the analyses. IVIG treatment had no beneficial effect on time to confirmed EDSS progression (hazard ratio 1.11 [95% CI 0.80-1.53] for IVIG versus placebo). The annual relapse rate was 0.46 in both groups. No significant differences between the treatment groups were found in any of the other clinical outcome measures or in the change of T2-lesion load over time. The treatment was generally well tolerated, although deep venous thrombosis, pulmonary embolism, or both occurred in seven patients with risk factors for thromboembolism (IVIG six, placebo one).

INTERPRETATION

Treatment with IVIG in this study did not show any clinical benefit and therefore cannot be recommended for patients with secondary progressive multiple sclerosis.

Haematopoietic stem cell transplantation for autoimmune disorders: the American perspective

The hypothesis that haematopoietic stem cell transplantation (HSCT) might be useful in treating refractory autoimmune diseases (AID) was suggested by studies in animal models and by the improvement of concurrent autoimmune diseases in patients who had undergone transplantation for haematological disorders. This concept has now been tested in a substantial number of phase I/II clinical trials of autologous HSCT. These early results are promising, even in patients who have failed on multiple standard therapies for AID. Transplantation-related toxicity has decreased with growing experience in the application of this procedure, better patient selection and the modification of treatment protocols. Randomized trials currently under way or under consideration should clarify the role of HSCT in patients with autoimmune disorders.

Stem cell transplantation for multiple sclerosis: What is the evidence?

Experimental and clinical observations have indicated that high-dose immunosuppression followed by autologous stem cell transplantation (ASCT) can induce remissions in severe, refractory, autoimmune diseases including multiple sclerosis (MS), a T cell-mediated autoimmune disorder against CNS myelin components, causing severe chronic disability. Control of the disease is unsatisfactory in most of the patients, especially those with rapidly evolving relapsing-remitting course and those with chronic progressive disease. The rationale for treating autoimmune diseases with ASCT is based on the immunosuppressive and immunomodulating effects of ASCT which may shift the immunological balance towards disease quiescence, a hypothesis supported by the results of ASCT in animal models of MS and by clinical observations in MS patients transplanted for concurrent malignancies. A number of phase I-II studies of ASCT in patients with active MS, conducted worldwide since 1995, and a comprehensive analysis of 85 patients, recently reported by the European Group for Blood and Marrow Transplantation (EBMT), have shown the feasibility of the method, a prominent anti-inflammatory effect on magnetic resonance imaging (MRI) disease, and a possible clinical benefit for active and refractory cases. The impact on MRI disease parameters appears superior with ASCT than with conventional therapies but the clinical results, in terms of stabilization of disease and prevention of disability, need to be validated in prospective, controlled trials. The procedure is also associated with a transplant-related mortality risk, of about 5% in high-risk cases, i.e., in older patients, those with high disability scores, those receiving strong myeloablative conditioning regimens and those undergoing intensive in vivo or ex vivo T cell-depletion. Therefore, it could be recommended for the treatment of a chronic, non-lethal, disease like MS only if it proved superior to standard therapies. A randomized trial is now launched by the EBMT to compare ASCT to mitoxantrone, currently regarded as one of the best available treatments, in properly selected patients having high chance of response at minimal mortality risk.

Assessment of different treatment failure criteria in a cohort of relapsing-remitting multiple sclerosis patients treated with interferon beta: implications for clinical trials

Clinical trials with interferons in relapsing-remitting multiple sclerosis have shown a modest effect on disability using fixed definitions of treatment failure to measure disease progression. However, in the course of the disease, treatment failure may be influenced by interrater variability and frequent remissions. Thus, the purpose of this study was to assess the clinical usefulness of different treatment failure criteria in a cohort of relapsing-remitting multiple sclerosis patients treated with interferon beta. We studied 252 patients with a follow-up of more than 2 years. We used four different criteria of treatment failure with increasing stringency (1 Expanded Disability Status Scale [EDSS] point increase confirmed at 3 months, 1 EDSS point increase confirmed at 6 months, 1.5 EDSS points increase confirmed at 3 months, and 1.5 EDSS points increase confirmed at 6 months). We divided treatment failure into permanent treatment failure and transient treatment failure. We considered permanent treatment failure when treatment failure was confirmed on the last two scheduled visits and transient treatment failure when treatment failure was not confirmed on these visits at different time points (9, 12, 18, and 24 months). We calculated the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of the different criteria of treatment failure to identify patients who achieved a high degree of disability after 4 years of follow-up. Regardless of the stringency of treatment failure definitions, a variable proportion of patients with treatment failure had transient treatment failure depending on the criterion applied. Patients with transient treatment failure had a significantly lower EDSS at entry compared with those with permanent treatment failure or no treatment failure. The number of relapses in patients with transient treatment failure did not differ from that of patients with permanent treatment failure. The criterion of confirmed 1 EDSS point increase at 6 months showed the best sensitivity (76.5%), with satisfactory specificity (89%). Our study shows that a large proportion of patients treated with interferon experience transient treatment failure that may affect outcome interpretation in clinical trials. Using a more strict criterion, as extending time to confirmation of EDSS deterioration, and longer follow-up may reduce this proportion of patients with transient treatment failure and improve the validity of the results attained in clinical trials.

Cost-effectiveness analysis of interferon beta in multiple sclerosis: a Markov process analysis

OBJECTIVE

The objective of this study was to examine the cost-effectiveness of preventive treatment with interferon beta (IFNB) versus no preventive treatment in patients with multiple sclerosis.

METHODS

The setting for this study was the United Kingdom. A lifetime Markov process model was constructed to model the average quality-adjusted life years (QALYs) and the costs of both treatment strategies. Data for the construction of the model came from published literature, including large multicenter randomized clinical trials in relapsing-remitting and secondary progressive multiple sclerosis. Costs were obtained from published sources.

RESULTS

The results of the baseline analysis from the National Health Service (NHS) perspective showed that the use of interferon beta as preventive treatment for MS increased the total average discounted cost from 51,214 Pounds to 221,436 Pounds per patient. The undiscounted effectiveness increased from 24.9 QALYs to 28.2 QALYs, resulting in an incremental cost-effectiveness ratio of 51,582 Pounds per QALY. Sensitivity analyses showed the robustness of this model for other interferons.

CONCLUSION

The study showed that preventive treatment with interferon beta in patients with multiple sclerosis may not be fully justified from a health-economic perspective, although interferon beta is associated with an improved effectiveness compared with no preventive treatment.

Disability outcome measures in therapeutic trials of relapsing-remitting multiple sclerosis: effects of heterogeneity of disease course in placebo cohorts

OBJECTIVES

Recent phase III clinical trials of immunomodulatory therapies in relapsing-remitting multiple sclerosis have shown significant benefits of active treatment on relapse related end points, but effects on disability outcomes have been inconsistent. These apparent discrepancies could be due to differences in the clinical end points employed, the behaviour of placebo cohorts, or both.

METHODS

Disability data from the placebo cohorts of two large phase III studies, the United States glatiramer acetate trial (Copolymer 1 Multiple Sclerosis Study Group) and the multinational interferon beta-1a trial (PRISMS Study Group) were combined and masked (n = 313). Two groups of disability outcome measures were assessed. Firstly, measures of disability change (2 year EDSS difference and area under the EDSS/time curve, AUC) were calculated. Secondly, conventional disease progression end points ("confirmed progression" and "worsening to EDSS 6.0") were evaluated by using Kaplan-Meier analysis and compared with a categorical classification based on EDSS trends.

RESULTS

The average increase in disability for the entire cohort as assessed by mean 2 year EDSS change (<0.5 EDSS point) or mean AUC (+0.57 EDSS-years) was small. For the "confirmed progression" end points, increasing the stringency of the definition lowered their incidence (from 32% with 1.0 point at 3 months, to 9% with 2.0 points at 6 months), but did not improve the positive predictive accuracy for "sustained progression" maintained to the end of the study. The error rate for this outcome was about 50%. Worsening to EDSS 6.0 was a more reliable end point, but had even lower sensitivity (incidence <10%). EDSS trend analysis showed markedly heterogeneous disease courses, which were then categorised into "stable" (26%), "relapsing-remitting" (59%), and "progressive" (15%) courses. Patients with the last course had deteriorated considerably by the end of 2 years (mean worsening of 2.0 EDSS points).

CONCLUSION

In relapsing-remitting multiple sclerosis treatment trials, the conventional measure of mean EDSS change has low sensitivity, whereas the widely applied confirmed progression end points have high error rates regardless of their definition stringency. Alternative methods with better data utilisation include AUC summary measures and categorical disease trend analysis. The heterogeneity of disability outcomes in short trials, combined with unreliable clinical end points, diminishes the credibility of therapeutic claims aimed at reducing irreversible neurological deficits. The behaviour of patients treated with placebo should be carefully analysed before conclusions are drawn on the efficacy of putative treatments.

Autologous stem cell transplantation in progressive multiple sclerosis--an interim analysis of efficacy

Based on the good results of experimental transplantation in animal models of multiple sclerosis and of other autoimmune diseases, we have treated 24 patients suffering from chronic progressive multiple sclerosis with high-dose chemotherapy (BEAM regimen) followed by autologous blood stem cell rescue and antithymocyte globulin. Blood stem cells were mobilised with cyclophosphamide at 4g/m2 and G- (or GM-) CSF. In 9 cases, additional CD34+ cell-selection of the graft was performed. Here we update previously published results of this novel treatment, mainly with regard to clinical efficacy, as the median follow-up time has reached 40 months (range, 21-51). Infections were the principal toxicity early after the procedure, with death of a patient from aspergillosis 65 days post stem cell infusion. No serious late events occurred apart from a case of autoimmune thyroiditis that developed 11 months after transplant in a patient who had received a CD34+ cell-depleted graft. Mild and transient neurotoxicity was observed in 10 patients (42%), most probably associated with fever and infections. Eighteen patients (18/23; 78%) responded to the treatment, i.e., they were improved or stabilized, while five patients progressed, of which 4 had primary progressive disease. Of those improved or stabilised (18), 9 patients have maintained stable condition whereas 9 developed relapses or they slowly resumed progression, although their disability scores have not gotten worse than they were before transplantation. The probability of progression-free survival (compared to entry status) at 3 years is 92% for patients with secondary progressive disease and 39% for the primary progressive type. CD34+ cell-selection did not seem to yield better results except for a delay in progression or in relapse after transplantation. These results appear better than those achieved by any other treatment of progressive multiple sclerosis, including beta-interferon, but they need to be confirmed by other open or controlled studies in view of the well-known difficulty of judging objectively the effect of a treatment in patients with this disease.

Treatment of progressive multiple sclerosis with pulse cyclophosphamide/methylprednisolone: response to therapy is linked to the duration of progressive disease

OBJECTIVE

To determine if there are variables linked to responsiveness to pulse cyclophosphamide/methylprednisolone therapy in progressive Multiple Sclerosis (MS).

BACKGROUND

MS is a presumed autoimmune disease of the CNS in which immunosuppressive and immunomodulatory treatments are being used. We have treated patients with the progressive form of MS using a regimen consisting of pulse cyclophosphamide/methylprednisolone that is given as an outpatient at 4 - 8 week intervals similar to lupus nephritis protocols.

DESIGN/METHODS

We investigated a series of 95 consecutive progressive MS patients treated in an open label fashion in an effort to identify factors linked to response to treatment. Clinical outcome measures included status at 12 months and time to failure determined by EDSS change and global physician impression. For each endpoint, associations were examined between outcome and patient characteristics including gender, age at onset of disease and treatment, EDSS 1 year previously and at start of treatment, duration of MS, previous treatment, age at onset and duration of progression, and primary vs secondary progressive MS.

RESULTS

Of the variables studied, age, gender, age at onset, and age at treatment did not correlate with response to therapy. The most significant variable that correlated with response was length of time the patient was in the progressive phase (P=0.048, 12 month change in EDSS; P=0.017, risk for time to failure). Patients that improved on therapy at 12 months had progressive disease for an average of 2.1 years prior to treatment, whereas those stable or worse had progressive disease for 5.0 and 4.1 years respectively. There was a trend (P=0.08) favoring positive clinical responses in secondary progressive as opposed to primary progressive patients.

CONCLUSIONS

Our data suggest that progressive MS may become refractory to immunosuppressive therapy with time and early intervention when patients enter the progressive stage should be considered. Furthermore, in trials of immunosuppressive agents for progressive MS, duration of progression should be considered as a randomization and analysis variable.

A prospective study on the natural history of multiple sclerosis: clues to the conduct and interpretation of clinical trials

The study's objectives were to assess the predictive significance of different sets of demographic, clinical and extraclinical variables in identifying multiple sclerosis patients with various risk levels of worsening during the follow-up, in order to provide clues to inclusion criteria and selection of primary clinical end-points in therapeutic trials. Two hundred and twenty-four patients at their first diagnosis of multiple sclerosis admitted to our Department between 1983 and 1990 were prospectively followed-up until the end of 1996. We considered as end-points time to reach non-reversible disability levels corresponding to EDSS scores of 4.0 and 6.0 and the beginning of a secondary progressive phase in the relapsing-remitting subgroup of patients. For the statistical treatment of our data we used the Kaplan-Meier survival curves and the Cox regression analysis. An initially progressive course and higher basal EDSS scores proved to be the best predictors of unfavorable prognosis; a greater number of functional systems involved at onset as well as higher residual deficits in pyramidal, visual, sphincteric and cerebellar systems were other factors predictive of a poor outcome, whereas sensory system involvement turned out to be favorable. In the relapsing-remitting subgroup, a longer first inter-attack interval was associated with a better prognosis; however, overall number of relapses in the first two years of the disease was of no prognostic value. The presence of oligoclonal banding in the cerebrospinal fluid and a cerebral MRI 'strongly suggestive' or 'suggestive' of MS in the early phases of the disease were associated with a higher probability of a worse outcome.

Quantification of impairment in MS: discussion of the scales in use

Accurate, efficient measurement of disease status has become a key issue in MS clinical practice and research. Despite some perceived problems, the Expanded Disability Status Scale (EDSS) remains the most widely used comprehensive measure of impairment. There is also a place for more restricted scales of impairment which focus on some aspects of neurological function in more detail than the EDSS e.g. measures of ambulation, arm function and cognitive function. Improvements in scales of impairment in the future is likely to result from the use of more quantitative tests of selected components of the neurological examination.

The natural history of multiple sclerosis: implications for trial design

The understanding of the natural history of multiple sclerosis has many implications for the design and interpretation of randomized controlled trials. Selection criteria, patient stratification, outcome measurements, and definitions of treatment failure can influence randomized controlled trial results and limit comparisons among trials. The focus of future studies should shift from short-term determinations of efficacy to definitive evaluations of long-term effectiveness. This will require novel investigative strategies such as the use of historic controls derived from natural history studies.

Predictive value of gadolinium-enhanced magnetic resonance imaging for relapse rate and changes in disability or impairment in multiple sclerosis: a meta-analysis. Gadolinium MRI Meta-analysis Group

BACKGROUND

Reliable prognostic factors are lacking for multiple sclerosis (MS). Gadolinium enhancement in magnetic resonance imaging (MRI) of the brain detects with high sensitivity disturbance of the blood-brain barrier, an early event in the development of inflammatory lesions in MS. To investigate the prognostic value of gadolinium-enhanced MRI, we did a meta-analysis of longitudinal MRI studies.

METHODS

From the members of MAGNIMS (European Magnetic Resonance Network in Multiple Sclerosis) and additional centres in the USA, we collected data from five natural-course studies and four placebo groups of clinical trials completed between 1992 and 1995. We included a total of 307 patients, 237 with relapsing disease course and 70 with secondary progressive disease course. We investigated by regression analysis the relation between initial count of gadolinium-enhancing lesions and subsequent worsening of disability or impairment as measured by the expanded disability status scale (EDSS) and relapse rate.

FINDINGS

The relapse rate in the first year was predicted with moderate ability by the mean number of gadolinium-enhancing lesions in monthly scans during the first 6 months (relative risk per five lesions 1.13, p=0.023). The predictive value of the number of gadolinium-enhancing lesions in one baseline scan was less strong. The best predictor for relapse rate was the variation (SD) of lesion counts in the first six monthly scans which allowed an estimate of relapse in the first year (relative risk 1.2, p=0.020) and in the second year (risk ratio=1.59, p=0.010). Neither the initial scan nor monthly scans over six months were predictive of change in the EDSS in the subsequent 12 months or 24 months. The mean of gadolinium-enhancing-lesion counts in the first six monthly scans was weakly predictive of EDSS change after 1 year (odds ratio=1.34, p=0.082) and 2 years (odds ratio=1.65, p=0.049).

INTERPRETATION

Although disturbance of the blood-brain barrier as shown by gadolinium enhancement in MRI is a predictor of the occurrence of relapses, it is not a strong predictor of the development of cumulative impairment or disability. This discrepancy supports the idea that variant pathogenetic mechanisms are operative in the occurrence of relapses and in the development of long-term disability in MS.