Long-term impact of interferon beta-1b in patients with CIS: 8-year follow-up of BENEFIT.

OBJECTIVE: To examine the long-term impact of early treatment initiation of interferon beta-1b (IFNB1b, Betaferon/Betaseron) in patients with a first event suggestive of multiple sclerosis (MS). METHODS: In the original placebo-controlled phase of BENEFIT, patients were randomised to IFNB1b 250 µg or placebo subcutaneously every other day. After 2 years or diagnosis of clinically definite MS (CDMS), all patients were offered open-label IFNB1b treatment for a maximum duration of 5 years. Thereafter, patients were enrolled in an observational extension study for up to 8.7 years. RESULTS: Of the initial 468 patients, 284 (60.7%; IFNB1b: 178 (61.0% of the original arm), placebo: 106 (60.2% of original arm)) were enrolled in the extension study. 94.2% of patients were receiving IFNB1b. Patients originally randomised to IFNB1b had a reduced risk of developing CDMS by 32.2% over the 8-year observation period (HR 0.678; 95% CI 0.525 to 0.875; p=0.0030), a longer median time to CDMS by 1345 days (95% CI 389 to 2301), and a lower annualised relapse rate (0.196 (95% CI 0.176 to 0.218) versus 0.255 (95% CI 0.226 to 0.287), p=0.0012), with differences mainly emerging in the first year of the study. Cognitive outcomes remained higher in the early treated patients. EDSS remained low over time with a median of 1.5 in both arms. CONCLUSIONS: These 8-year results provide further evidence supporting early initiation of treatment with IFNB1b in patients with a first event suggestive of MS.

Predictive nature of IgM anti-α-glucose serum biomarker for relapse activity and EDSS progression in CIS patients: a BENEFIT study analysis.

BACKGROUND: Higher serum levels of at least one of a panel of four α-glucose IgM antibodies (gMS-Classifier1) in clinically isolated syndrome (CIS) patients are associated with imminent early relapse within 2 years. OBJECTIVE: The objective of this study was to determine the prognostic value of gMS-Classifier1 in a large study cohort of CIS patients. METHODS: The BEtaseron(®) in Newly Emerging multiple sclerosis For Initial Treatment (BENEFIT) 5-year study was designed to evaluate the impact of early versus delayed interferon-ß-1b (IFNß-1b; Betaseron(®)) treatment in patients with a first event suggestive of multiple sclerosis (MS). Patients (n = 258, 61% of total) with a minimum of 2 ml baseline serum were eligible for the biomarker study. gMS-Classifier1 antibodies' panel (anti-GAGA2, anti-GAGA3, anti-GAGA4 and anti-GAGA6) levels were measured blinded to clinical data. Subjects were classified as either 'positive' or 'negative' according to a classification rule. RESULTS: gMS-Classifier1 was not predictive for the time to clinically definite MS or time to MS according to the revised McDonald's criteria, but did significantly predict an increased risk for confirmed disability progression (log-rank test: p = 0.012). CONCLUSIONS: We could not confirm previous results that gMS-Classifier1 can predict early conversion to MS in CIS. However, raised titres of these antibodies may predict early disability progression in this patient population.

Interferon ß-1b-neutralizing antibodies 5 years after clinically isolated syndrome.

OBJECTIVE: To determine the frequency and consequences of neutralizing antibodies (NAbs) in patients with a first event suggestive of multiple sclerosis (MS) treated with interferon ß-1b (IFNß-1b). METHODS: In the Betaseron/Betaferon in Newly Emerging MS For Initial Treatment (BENEFIT) study, patients were randomly assigned to 250 µg IFNß-1b (Betaferon) or placebo subcutaneously every other day for 2 years or until diagnosis of clinically definite MS (CDMS). Patients were then offered open-label IFNß-1b for up to 5 years. NAb status was assessed every 6 months by the myxovirus protein A induction assay. A titer >20 NU/mL was considered NAb-positive, with low (≥20-100 NU/mL), medium (≥100-400 NU/mL), and high (≥400 NU/mL) titer categories. Here we examine early-treated patients, who received IFNß-1b for up to 5 years. RESULTS: NAbs were measured in 277 of 292 early-treated patients and detected at least once in 88 (31.8%) patients, with 53 (60.2%) reverting to NAb negativity by year 5. Time to CDMS, time to confirmed disability progression, and annualized relapse rate did not differ between NAb-positive and NAb-negative patients or between periods of NAb positivity vs NAb negativity within patients. Increases in newly active lesion number and T2 lesion volume and conversion to McDonald MS were associated with NAb positivity and were more pronounced with higher titers. CONCLUSIONS: Although NAb positivity was associated with increased brain MRI activity, no discernible effects on clinical outcomes were found. This finding may reflect the greater power of MRI compared with clinical outcomes to detect the treatment effects of IFNß-1b and may also result from temporal changes in NAb titers and biology.

Can the functional assessment of multiple sclerosis adapt to changing needs? A psychometric validation in patients with clinically isolated syndrome and early relapsing-remitting multiple sclerosis.

BACKGROUND: The Functional Assessment of Multiple Sclerosis (FAMS) is widely used in clinical trial programmes; however, it was developed before the rise in trials targeted at early stage multiple sclerosis (MS) and clinically isolated syndrome (CIS). OBJECTIVE: The aim of this study was to assess the psychometric properties of the FAMS within two clinically distinct populations, CIS and early relapsing-remitting MS (RRMS), and discern the appropriateness of the FAMS within these populations. METHODS: Secondary analysis was conducted on FAMS data from two clinical trials assessing interferon beta-1b in early RRMS and CIS. The statistical analysis assessed the scale acceptability, reliability, validity and responsiveness of the FAMS. Item response theory (IRT) was also conducted on the early RRMS sample in order to assess how well the FAMS discriminated amongst individuals with less severe MS. RESULTS: Results from both trials demonstrated an improvement in the FAMS psychometric properties with increased baseline disease severity. However, high ceiling effects were evident amongst less severe patients, and there was an overall lack of responsiveness to improvement and poor construct validity. IRT also demonstrated its lack of discrimination/sensitivity in early RRMS. CONCLUSIONS: In trials involving patients with early stage RRMS and CIS, modifications to the FAMS based on a qualitative assessment of its content validity in these populations would be required in order to potentially improve the FAMS psychometric properties and sensitivity.

Interferon ß-1b and glatiramer acetate effects on permanent black hole evolution.

OBJECTIVE: To compare interferon ß-1b (IFNß-1b) and glatiramer acetate (GA) on new lesion (NL) (gadolinium-enhancing, new T2) evolution into permanent black holes (PBH)--a marker of irreversible tissue damage--in patients with relapsing-remitting multiple sclerosis (RRMS). METHODS: BEYOND was a large, phase III, clinical trial comparing IFNß-1b 250 µg, IFNß-1b 500 µg, and GA (2:2:1). Patient scans were reexamined post hoc for PBH in a rater-blinded manner. Two predefined coprimary endpoints compared IFNß-1b 250 µg with GA: first, number of PBH per patient at year 2 evolving from year 1 NL, then proportion of year 1 NL evolving into PBH at year 2. IFNß-1b 500 µg and GA were compared in an exploratory fashion. RESULTS: Approximately 90% (1,957/2,244) of patients had NL at year 1 with follow-up at year 2. Mean numbers of PBH per patient at year 2 evolving from year 1 NL were lower for IFNß-1b 250 µg than GA (0.30 vs 0.43; p = 0.0451). The proportion of NL evolving into PBH was similar (IFNß-1b 250 µg vs GA: 21.6% vs 23.5%; p > 0.20). For IFNß-1b 500 µg, both the mean PBH number per patient at year 2 evolving from year 1 NL (0.26 vs 0.43; p = 0.0037) and proportion of NL evolving into PBH (16.3% vs 23.5%; p = 0.0409) were lower relative to GA. CONCLUSION: IFNß-1b affected PBH development to a similar or better extent than GA. IFNß-1b favorably influences an MRI outcome indicative of permanent tissue destruction in the brains of patients with multiple sclerosis. CLASSIFICATION OF EVIDENCE: This study provides Class III evidence that IFNß-1b is associated with a reduction in MRI PBH formation and evolution compared with GA between years 1 and 2 of treatment.

Lesional magnetization transfer ratio: a feasible outcome for remyelinating treatment trials in multiple sclerosis.

Magnetization transfer ratio (MTR) is a sensitive parameter to quantify the integrity of myelinated white matter in patients with multiple sclerosis. Lesional MTR decreases in the acute phase due to demyelination, and subsequently shows recovery depending on the degree of remyelination in the absence of axonal loss. Recovery of average lesion MTR therefore might prove a viable outcome measure to assess the effect of remyelinating agents. Our objective was to determine the required sample size for phase II multicentre clinical trials using the recovery of average lesion MTR as primary outcome measure. With 7-monthly MRI scans, the MTR evolution of 349 new enhancing lesions before and after enhancement was assessed in 32 MS patients from 5 centres. Multilevel models were fitted to the data yielding estimates for the variance components, which were applied in power calculations. Sample sizes were determined for placebo-controlled, multicentre trials using lesional MTR recovery post-enhancement as primary outcome measure. Average lesion MTR decreased slightly in the build-up to enhancement, decreased dramatically during enhancement and showed recovery in the period after cessation. The power calculations showed that for a power of 80%, approximately 136 patients per trial (mean number of 6 lesions per patient) are required to detect a 30% increase in lesional MTR post-enhancement compared with placebo, whereas 48 subjects are required to detect a 50% increase in lesional MTR compared with placebo. Recovery of lesion MTR is a feasible outcome measure for future multicentre clinical trials measuring the effect of remyelinating agents.

Cerebral atrophy as outcome measure in short-term phase 2 clinical trials in multiple sclerosis.

INTRODUCTION: Cerebral atrophy is a compound measure of the neurodegenerative component of multiple sclerosis (MS) and a conceivable outcome measure for clinical trials monitoring the effect of neuroprotective agents. In this study, we evaluate the rate of cerebral atrophy in a 6-month period, investigate the predictive and explanatory value of other magnetic resonance imaging (MRI) measures in relation to cerebral atrophy, and determine sample sizes for future short-term clinical trials using cerebral atrophy as primary outcome measure. METHODS: One hundred thirty-five relapsing-remitting multiple sclerosis patients underwent six monthly MRI scans from which the percentage brain volume change (PBVC) and the number and volume of gadolinium (Gd)-enhancing lesions, T2 lesions, and persistent black holes (PBH) were determined. By means of multiple linear regression analysis, the relationship between focal MRI variables and PBVC was assessed. Sample size calculations were performed for all patients and subgroups selected for enhancement or a high T2 lesion load at baseline. RESULTS: A significant atrophy occurred over 6 months (PBVC = -0.33%, SE = 0.061, p < 0.0001). The number of baseline T2 lesions (p = 0.024), the on-study Gd-enhancing lesion volume (p = 0.044), and the number of on-study PBHs (p = 0.003) were associated with an increased rate of atrophy. For a 50% decrease in rate of atrophy, the sample size calculations showed that approximately 283 patients per arm are required in an unselected sampled population and 185 patients per arm are required in a selected population. CONCLUSION: Within a 6-month period, significant atrophy can be detected and on-study associations of PBVC and PBHs emphasizes axonal loss to be a driving mechanism. Application as primary outcome measure in short-term clinical trials with feasible sample size requires a potent drug to obtain sufficient power.

Persistent T1 hypointensity as an MRI marker for treatment efficacy in multiple sclerosis.

BACKGROUND: MRI is often used as primary outcome measure in phase II clinical trials in multiple sclerosis (MS). Since persistent T1 hypointense lesions are a surrogate parameter for axonal damage and demyelination, they may serve as a marker for monitoring the efficacy of neuroprotective drugs. At present, a power analysis using black hole (BH) evolution as primary outcome measure has not been performed. OBJECTIVE: To assess the feasibility of using BH evolution on serial brain MR images as primary outcome measure in proof of concept studies in MS. METHODS: MRI-data obtained from 169 active RRMS patients were analysed for BH evolution by determining the cumulative number of contrast enhancing lesions (CEL) evolving into a persistent black hole (PBH) after 3 months. With a parametric simulation procedure, based on a statistical distribution fitting the data, sample sizes were calculated. RESULTS: 21.2% of the total number of CELs observed during the study period evolved into a PBH. Ring enhancing lesions evolved most frequently into a PBH (59.4%), followed by lesions larger than 10 mm (57.4%) and periventricular CELs (30.6%). The simulation procedure, based on the statistical negative binomial (NB) model resulted in a sample sizes between 200 subjects and 30 subjects per arm, for treatment effects ranging from 50% to 90% reduction of the number of CELs evolving into a PBH, respectively. CONCLUSION: To perform a MRI monitored phase II clinical trial with a feasible sample size, using the evolution of CELs into PBHs as primary outcome parameter, a potent drug is required to obtain sufficient power.

Classification of patients with a clinically isolated syndrome based on signs and symptoms is supported by magnetic resonance imaging results.

BACKGROUND: Recently, a clinical classification system was described to determine whether symptoms and signs of patients presenting with a first episode suggestive of multiple sclerosis (MS) indicate the presence of monofocal or multifocal disease. OBJECTIVES: To evaluate the value of this new classification system by comparing the results with those of simultaneously obtained magnetic resonance imaging (MRI) scans. METHODS: The 487 patients, randomised in the BENEFIT study, were centrally assessed using the new system and classified as monofocal or multifocal, based on clinical information by two neurologists masked for the MRI results. MRI analyses were performed by expert readers masked for the clinical classification. RESULTS: Patients classified as multifocal had more T2 hyperintense (median: 21 versus 15.5) and more T1 hypo-intense lesions (median: 2 versus 1) than those classified as monofocal. Patients classified at the local site as having evidence of a single clinical lesion, but reclassified centrally as having a clinical multifocal central nervous system presentation, had more T2 lesions than monofocal patients. In addition, patients with a multifocal presentation more often fulfilled the MRI criteria for dissemination in space, as incorporated in the International Panel (IP) diagnostic criteria for MS. CONCLUSION: These data provide justification for the recently proposed clinical classification system to be used in patients who present with a first episode suggestive of MS, in that ;multifocal', based on symptoms and signs, is associated with more lesions on MRI.

Blockade of chemokine signaling in patients with multiple sclerosis.

We assessed the safety and efficacy of orally administered CC chemokine receptor 1 (CCR1) antagonist in 105 patients with relapsing/remitting MS (RRMS) in a 16-week, randomized, double-blind, placebo-controlled trial. The primary endpoint was the cumulative number of newly active lesions on serial MRI scans. Other MRI, immunologic, and clinical outcomes were also explored. No significant treatment difference was observed for any tested MRI variable. CCR1 does not contribute to initial leukocyte infiltration in RRMS.

Treatment with interferon beta-1b delays conversion to clinically definite and McDonald MS in patients with clinically isolated syndromes.

OBJECTIVE: To assess efficacy, safety, and tolerability of every-other-day interferon beta-1b treatment in patients with a first clinical event suggestive of multiple sclerosis (MS) (clinically isolated syndrome). METHODS: We conducted a multicenter, randomized, double-blind, placebo-controlled trial. Patients with a first clinical demyelinating event and at least two clinically silent brain MRI lesions were randomized to interferon beta-1b (IFNB-1b) 250 mug subcutaneously (SC) every other day (EOD) (n = 292) or placebo (n = 176), until clinically definite MS (CDMS) was diagnosed or they had been followed for 24 months. RESULTS: After 2 years, 45% of placebo patients had converted to CDMS (Kaplan-Meier estimate; primary outcome measure) and 85% fulfilled the McDonald criteria (co-primary outcome measure). Overall interferon beta-1b delayed the time to diagnosis of CDMS (p < 0.0001) and McDonald MS (p < 0.00001). Hazard ratios (95% CI) were 0.50 (0.36 to 0.70) for CDMS and 0.54 (0.43 to 0.67) for McDonald MS favoring treatment with IFNB-1b. Treatment was well tolerated, as indicated by the low rate of patients dropping out of the study before CDMS was reached (6.6% overall, 7.2% in the IFNB-1b group). CONCLUSIONS: Interferon beta-1b 250 mug subcutaneously every other day delayed conversion to clinically definite multiple sclerosis, and should be considered as a therapeutic option in patients presenting with a first clinical event suggestive of multiple sclerosis.

Oral interferon beta-1a in relapsing-remitting multiple sclerosis: a double-blind randomized study.

BACKGROUND: Interferon beta (IFNB) is available in parenteral formulations for treatment of multiple sclerosis (MS). The purpose of this study was to evaluate safety, tolerability and effects on MRI lesions of three different doses of oral IFNB-1a compared with placebo over six months in relapsing-remitting (RR) MS patients. METHODS: In this multicenter; double-blind randomized trial, RR-MS patients received 0.06, 0.6 or 6 million international units (MIU) IFNB-1a or placebo every other day for up to six months. Gadolinium DTPA-enhanced brain MRI scans were performed at screening and monthly during treatment. The primary variable was the cumulative number of newly active lesions. Secondary variables included volume of enhancing lesions on T1-weighted images each month and lesion volume on T2-weighted images at months three and six. Safety measures included adverse events, laboratory variables, vital signs, ECG, physical examination, EDSS and number of relapses. Neopterin was measured in 21 patients and neutralizing antibodies in 24 patients. RESULTS: Of 194 screened patients, 173 were randomized (42-44 patients per group) in 15 centers. Median cumulative numbers of newly active lesions over six months were 4.0 in the placebo and 0.6 MIU groups, compared with 7.5 and 9.0 in the 0.06 and 6 MIU groups (no significant differences). Secondary efficacy endpoints showed small and inconsistent differences between groups. Adverse events showed no notable group differences. Approximately two-thirds of patients in each group remained relapse free. No patients showed neutralizing antibodies. Neopterin levels were comparable between groups. CONCLUSION: Oral IFNB-1a showed neither beneficial effects in RRMS nor any systemic biological effects. Treatment was safe and well tolerated.

Interaction of the Presenilins with the Amyloid Precursor Protein (APP).

The genes encoding presenilin-1 (PS1) and presenilin-2 (PS2) were identified as the genes that harbour mutations that cause more than 60% of early onset familial Alzheimer's disease cases (FAD) (1-3). So far, more than 40 missense mutations have been described for presenilin-1 and two have been found in the gene coding for presenilin-2 (reviewed in refs. 4 and 5). Carriers of mutated presenilin genes develop in their brain neuropathological changes characteristic of Alzheimer's disease including the deposition of amyloid Aß peptide. The latter is released from its cognate amyloid precursor protein (APP) by a two-step proteolytic conversion: first, proteolysis of APP by ß-secretase, which releases the N-terminus of Aß, and second, conversion of the remaining fragment by γ-secretase, which cleaves within the predicted transmembrane region of APP. This releases the C-terminus of Aß, which may end either at position 40 or, to a lesser extent, at position 42 (reviewed in ref. 6). The latter species, Aß(1-42), is more prone to aggregation and deposition than Aß(1-40) and is produced at higher levels in the brains and primary fibroblasts of FAD patients carrying PS missense mutations (7). The same result was obtained when cultured cells transfected with mutated PS1 orPS2, or transgenic mice harboring missense PS1 were analyzed for the production of Aß(1-42): in every case increased amounts of the longer Aß(1-42) species were observed (8-10). The mechanisms by which mutations in the PS genes affect the proteolytic processing of APP by γ-secretase have not been resolved in detail. There are two possibilities by which the normal processing of APP may be disturbed: either mutations in the presenilins affect APP metabolism in an indirect way by modulation of proteases or interaction with proteins involved in APP intracellular routing, or presenilins may modulate APP processing directly through physical interactions with APP. Such a direct interaction between presenilins and APP was first demonstrated by us for PS2 (11). Later on, formation of stable complexes with APP was reported not only for PS2 but also for PS1 (12,13,13a).

Cerebral changes and cerebrospinal fluid beta-amyloid in Alzheimer's disease: a study with quantitative magnetic resonance imaging.

Pathological and biochemical studies indicate that beta-amyloid (betaA4) deposition is a hallmark in the pathogenesis of Alzheimer's disease (AD). Neuroimaging studies demonstrate that the respective cerebral changes primarily strike the temporal lobe and the amygdala-hippocampus complex and may be reliably assessed using quantitative magnetic resonance imaging (MRI). Therefore one may expect that reduced betaA4-levels are significantly correlated with measures of the temporal lobe rather than global cerebral atrophy in AD patients. To test this hypothesis in a clinical study, cerebrospinal fluid concentrations of total betaA4 and its major C-terminal variations betaA4 1-40 and betaA4 1-42 were compared with cerebral changes as assessed by quantitative magnetic resonance imaging (MRI). Significantly (P< 0.05) reduced betaA4 1-40 and betaA4 1-42 levels were found in the AD patients (17 female; six male; AD/NINCDS-ADRDA-criteria) in comparison to the patients with major depression (seven female; two male; DSM-III-R). Within the AD group, betaA4 and betaA4 1-42 levels were significantly correlated with the volume of the temporal lobes (r= 0.46 and r= 0.48, respectively) but none of the other volumetric measures. These findings indicate that changes in cerebral betaA4 levels contribute to temporal lobe atrophy in AD and support the possibility that betaA4 is central to the etiology of AD.

Expression of the APP gene family in brain cells, brain development and aging.

The Alzheimer's beta A4-amyloid protein precursor (APP) and the APP-like proteins (APLPs) are transmembrane glycoproteins with a similar modular domain structure. Alternatively spliced exons found in both genes comprise a Kunitz protease inhibitor domain encoding exon, and another exon within the divergent regions adjacent to the transmembrane domain, i.e. exon 15 of the APP gene and an exon encoding 12 residues in APLP2. Omission of the latter exons in L-APP and L-APLP2 isoforms, respectively, generates a functional recognition sequence for xylosyltransferase-mediated addition of glycosaminoglycans and proteoglycan formation. In this paper, we summarize our analyses of the regulated expression of these alternatively spliced exons in APP and APLP2 in primary cultured rat brain cells, rat brain development and aging. In conjunction with additional data for the human brain, these data provide important clues for understanding the functional significance of alternative splicing and glycosylation in APP biology. On the basis of recent results showing a higher amyloidogenicity of exon 15 encoding APP than L-APP isoforms, we further discuss the potential significance of the low levels of L-APP in neurons for the susceptibility of the brain towards Alzheimer's disease.

Unraveling the molecular pathway of Alzheimer's disease: research about presenilins gathers momentum.

Missense mutations of the presenilins (PS1 and PS2) first identified about one year ago are responsible for the majority of autosomal dominant familial Alzheimer's disease cases. Recent studies suggesting that these mutations exert their disastrous effect by elevating the levels of the longer form of beta-amyloid (A beta 42) are reviewed.

Analysis of heterogeneous A4 peptides in human cerebrospinal fluid and blood by a newly developed sensitive Western blot assay.

The betaA4 peptide, a major component of senile plaques in Alzheimer's disease (AD) brain, has been found in cerebrospinal fluid (CSF) and blood of both AD patients and normal subjects. Although betaA4 1-40 is the major form produced by cell metabolism and found in CSF, recent observations suggest that the long-tailed betaA4 1-42 plays a more crucial role in AD pathogenesis. Here, we established new monoclonal antibodies against the C-terminal end of betaA4 1-40 and 1-42, and used them for the specific Western blot detection. After optimizing the assay conditions, these antibodies detected low picogram amount of betaA4, and both betaA4 1-40 and 1-42 levels in CSF could be determined by direct loading of the samples. Blood levels of betaA4 1-40 and 1-42 were also determined by specific immunoprecipitation followed by Western blot detection. We found that CSF betaA4 1-42 level is lower in AD patients compared with non-demented controls, although there was a significant overlap between the groups. The level of betaA4 1-40 in CSF, and of betaA4 1-40 as well as betaA4 1-42 in plasma, were not different between AD patients and controls. Besides the 4-kDa full-length betaA4 band, we could also detect several N-terminal variants of betaA4 in CSF and plasma of both AD patients and controls. Two N-terminally truncated betaA4 species migrating at the position of 3.3 and 3.7 kDa were found in CSF, while 3.7- and 5-kDa forms were found in plasma. The relative abundance of these various species were considerably different in the CSF and plasma, suggesting that the cellular source and/or clearance of betaA4 is different in these two compartments.