Interferon-ß corrects massive gene dysregulation in multiple sclerosis: Short-term and long-term effects on immune regulation and neuroprotection.

BACKGROUND: In multiple sclerosis (MS), immune up-regulation is coupled to subnormal immune response to interferon-ß (IFN-ß) and low serum IFN-ß levels. The relationship between the defect in IFN signalling and acute and long-term effects of IFN-ß on gene expression in MS is inadequately understood. METHODS: We profiled IFN-ß-induced transcriptome shifts, using high-resolution microarrays on 227 mononuclear cell samples from IFN-ß-treated MS Complete Responders (CR) stable for five years, and stable and active Partial Responders (PR), stable and active untreated MS, and healthy controls. FINDINGS: IFN-ß injection induced short-term changes in 1,200 genes compared to baseline expression after 4-day IFN washout. Pre-injection after washout, and in response to IFN-ß injections, PR more frequently had abnormal gene expression than CR. Surprisingly, short-term IFN-ß induced little shift in Th1/Th17/Th2 gene expression, but up-regulated immune-inhibitory genes (ILT, IDO1, PD-L1). Expression of 8,800 genes was dysregulated in therapy-naïve compared to IFN-ß-treated patients. These long-term changes in protein-coding and long non-coding RNAs affect immunity, synaptic transmission, and CNS cell survival, and correct the disordered therapy-naïve transcriptome to near-normal. In keeping with its impact on clinical course and brain repair in MS, long-term IFN-ß treatment reversed the overexpression of proinflammatory and MMP genes, while enhancing genes involved in the oligodendroglia-protective integrated stress response, neuroprotection, and immunoregulation. In the rectified long-term signature, 277 transcripts differed between stable PR and CR patients. INTERPRETATION: IFN-ß had minimal short-term effects on Th1 and Th2 pathways, but long-term it corrected gene dysregulation and induced immunoregulatory and neuroprotective genes. These data offer new biomarkers for IFN-ß responsiveness. FUNDING: Unrestricted grants from the US National MS Society, NMSS RG#4509A, and Bayer Pharmaceuticals.

Effect of HLA-DRB1 alleles and genetic variants on the development of neutralizing antibodies to interferon beta in the BEYOND and BENEFIT trials.

BACKGROUND: Treatment of multiple sclerosis (MS) with interferon ß can lead to the development of antibodies directed against interferon ß that interfere with treatment efficacy. Several observational studies have proposed different HLA alleles and genetic variants associated with the development of antibodies against interferon ß. OBJECTIVE: To validate the proposed genetic markers and to identify new markers. METHODS: Associations of genetic candidate markers with antibody presence and development were examined in a post hoc analysis in 941 patients treated with interferon ß-1b in the Betaferon® Efficacy Yielding Outcomes of a New Dose (BEYOND) and BEtaseron®/BEtaferon® in Newly Emerging multiple sclerosis For Initial Treatment (BENEFIT) prospective phase III trials. All patients were treated with interferon ß-1b for at least 6 months. In addition, a genome-wide association study was conducted to identify new genetic variants. RESULTS: We confirmed an increased risk for carriers of HLA-DRB1*04:01 (odds ratio (OR) = 3.3, p = 6.9 × 10-4) and HLA-DRB1*07:01 (OR = 1.8, p = 3.5 × 10-3) for developing neutralizing antibodies (NAbs). Several additional, previously proposed HLA alleles and genetic variants showed nominally significant associations. In the exploratory analysis, variants in the HLA region were associated with NAb development at genome-wide significance (OR = 2.6, p = 2.30 × 10-15). CONCLUSION: The contribution of HLA alleles and HLA-associated single-nucleotide polymorphisms (SNPs) to the development and titer of antibodies against interferon ß was confirmed in the combined analysis of two multi-national, multi-center studies.

Incidence and course of depression in multiple sclerosis in the multinational BEYOND trial.

Early experience in MS generated concerns that interferon beta treatment might provoke onset or worsening of depression. The objective of the study was to compare depression incidence in relapsing-remitting MS patients receiving interferon beta-1b (IFNB-1b) or glatiramer acetate (GA) in the BEYOND trial. 891/897 (99 %) of English, French, Spanish and Italian speakers among 2244 patients randomized (2:2:1) to receive either IFNB-1b 500 µg, 250 µg, or GA 20 mg QD for 2-3.5 years submitted Beck Depression Inventory Second Edition (BDI-II) scores at screening and serially thereafter, in which scores ≥14 indicated depression. Baseline BDI-II scores ≥14 were reported in 232/891 patients (26.3 %), with no meaningful difference among the three treatment arms noted at this or at any other time during the study including trial end. Percentages of patients depressed by BDI-II scores deviated little in any arm at any time (IFNB-1b 500 µg: 24.7 %, IFNB-1b 250 µg: 24.4 %, GA: 32.4 %). Antidepressant usage was likewise similar among the three treatment arms (IFNB-1b 500 µg: 33.7 %, IFNB-1b 250 µg: 31.8 %, GA: 28.8 %) as was depression severity and the frequency with which non-blinded treating physicians recorded depression as an adverse event (IFNB-1b 500 µg: 17.2 %, IFNB-1b 250 µg: 17.0 %, GA: 14.4 %). Treating physicians attributed depression to IFNB-1b 250 µg therapy in 53.6 % and to GA in 21.9 % of instances. This large, prospective, randomized-controlled MS dataset showed no increased risk of depression above baseline values with standard or double-dose IFNB-1b or GA QD treatment.

Association of Vitamin D Levels With Multiple Sclerosis Activity and Progression in Patients Receiving Interferon Beta-1b.

IMPORTANCE: Low serum 25-hydroxyvitamin D (25[OH]D) levels are associated with an increased risk of multiple sclerosis (MS) as well as with increased disease activity and rate of progression in clinically isolated syndromes and early MS. OBJECTIVE: To assess the association between 25(OH)D and disease course and prognosis in patients with relapsing-remitting MS treated with interferon beta-1b. DESIGN, SETTING, AND PARTICIPANTS: We conducted a prospective cohort study assessing 25(OH)D levels and subsequent MS disease course and progression characterized by magnetic resonance imaging (MRI) and clinical end points. The study took place between November 2003 and June 2005; data analysis was performed between June 2013 and December 2014. The study was conducted among participants in the Betaferon Efficacy Yielding Outcomes of a New Dose (BEYOND) study, a large, phase 3, prospective, multicenter, blinded, randomized clinical trial. Patients were monitored for at least 2 years. Clinic visits were scheduled every 3 months, and MRI was performed at baseline and annually thereafter. Eligible patients included 1482 participants randomized to receive 250 µg or 500 µg of interferon-1b with at least 2 measurements of 25(OH)D obtained 6 months apart. EXPOSURES: Serum 25(OH)D measurements were performed at baseline, 6 months, and 12 months. MAIN OUTCOMES AND MEASURES: Main outcomes included cumulative number of new active lesions (T2 lesions and gadolinium acetate-enhancing lesions), change in normalized brain volume, relapse rate, and progression determined by the Expanded Disability Status Scale (EDSS). Statistical analyses were adjusted for age, sex, randomized treatment, region, disease duration, and baseline EDSS score. RESULTS: Overall, average 25(OH)D levels in 1482 patients were significantly inversely correlated with the cumulative number of new active lesions between baseline and the last MRI, with a 50.0-nmol/L increase in serum 25(OH)D levels associated with a 31% lower rate of new lesions (relative rate [RR], 0.69; 95% CI, 0.55-0.86; P = .001). The lowest rate of new lesions was observed among patients with 25(OH)D levels greater than 100.0 nmol/L (RR, 0.53; 95% CI, 0.37-0.78; P = .002). No significant associations were found between 25(OH)D levels and change in brain volume, relapse rates, or EDSS scores. Results were consistent following adjustment for HLA-DRB1*15 or vitamin D-binding protein status. CONCLUSIONS AND RELEVANCE: Among patients with MS treated with interferon beta-1b, higher 25(OH)D levels were associated with lower rates of MS activity observed on MRI. Results for brain atrophy and clinical progression were more equivocal.

Predictors of disease activity in 857 patients with MS treated with interferon beta-1b.

Multiple sclerosis (MS) is a chronic demyelinating neurodegenerative disease of the CNS that requires long-term treatment. The identification of patient characteristics that can help predict disease outcomes could improve care for patients with MS. The objective of this study is to identify predictors of disease activity in patients from the BEYOND trial. This regression analysis of patients with relapsing-remitting MS from BEYOND examined the predictive value of patient characteristics at baseline and after 1 year of treatment with interferon beta-1b 250 µg every other day for clinical and MRI outcomes after year 1 of the study. 857 and 765 patients were included in the analyses of clinical and MRI outcomes, respectively. In multivariate analyses of age, a higher number of relapses in the past 2 years, ≥3 new MRI lesions in the first year, and, especially, a higher number of relapses in year 1 predicted the future occurrence of relapses. By contrast, age, MRI activity, and the presence of neutralizing antibodies in the first year were principally predictive of future MRI activity. In patients with continued clinical disease activity or substantial MRI activity on therapy, an alternative therapeutic approach should be strongly considered.

Efficacy and safety of interferon beta-1b sc in older RRMS patients--a posthoc analysis of the BEYOND study.

Evidence of a significant improvement of IFNB-1b in clinical severity in the older population with RRMS has not been established so far. The aim of this exploratory post hoc analysis of the 250 mcg IFNB-1b group of the BEYOND study is to compare the efficacy and safety of older versus younger patients using a cut-off at the age of 50 and at the age of 40, respectively. There was no difference between age groups in adjusted relapse risk (age 50 cut-off: P = 0.482, age 40 cut-off: P = 0.073) nor in adjusted time to confirmed EDSS progression (age 50 cut-off: P = 0.096, age 40 cut-off: P = 0.189). There were no significant differences between patients <50 and ≥ 50 years in the adjusted annualized relapse rate (P = 0.285), whereas relapse rate was higher in the <40 as compared to the ≥ 40 group (P = 0.024). The proportion of patients with confirmed disability progression was not significantly different for the 50 cutoff (P = 0.148), whereas significantly fewer <40 than ≥ 40 patients had disability progression (P = 0.047). Only minor differences in adverse event frequencies between the age groups for the two cut-offs were seen. These results indicate that IFNB-1b is as efficacious and safe in patients ≥ 50 years as <50 years of age.

Mechanisms of action of adrenocorticotropic hormone and other melanocortins relevant to the clinical management of patients with multiple sclerosis.

The therapeutic benefits of adrenocorticotropic hormone in multiple sclerosis are usually ascribed to its corticotropic actions. Evidence is presented that adrenocorticotropic hormone, approved for multiple sclerosis relapses, acts via corticosteroid-independent melanocortin pathways to engender down-modulating actions on immune-system cells and the cytokines they synthesize. Immune response-dampening effects are also brought about by agent-induced neurotransmitters that inhibit immunocytes. The likelihood that adrenocorticotropic hormone promotes microglial quiescence and counteracts glucocorticoid-mediated bone resorption is discussed.

Variability in detection and quantification of interferon ß-1b-induced neutralizing antibodies.

BACKGROUND: Interferon-beta (IFNB) therapy for multiple sclerosis can lead to the induction of neutralizing antibodies (NAbs) against IFNB. Various methods are used for detection and quantification of NAbs. METHODS: Blood samples from 125 IFNB-1b-treated patients, which were tested NAb negative or NAb positive after conclusion of a clinical study, were retested three years after first being assessed in four different laboratories that offer routine NAb testing to practicing neurologists. The myxovirus protein A (MxA) induction assay, the cytopathic effect (CPE) assay (two laboratories), or the luciferase assay were used. Intra- and inter-laboratory agreement between assays with respect to NAb detection and NAb titer quantification were evaluated. RESULTS: High agreement for NAb detection (kappa coefficient, 0.86) and for titer levels was observed for the intra-laboratory comparison in the laboratory using the MxA induction assay performed three years ago and now. A similarly high agreement for NAb detection (kappa coefficient, 0.87) and for titer quantification was noted for the MxA assay of this laboratory with one of two laboratories using the CPE assay. All other inter-laboratory comparisons showed kappa values between 0.57 and 0.68 and remarkable differences in individual titer levels. CONCLUSIONS: There are considerable differences in the detection and quantification of IFNB-induced NAbs among laboratories offering NAb testing for clinical practice using different assay methods. It is important that these differences are considered when interpreting NAb results for clinical decision-making and when developing general recommendations for potentially clinically meaningful NAb titer levels.

Neutralizing antibodies to interferon beta-1b multiple sclerosis: a clinico-radiographic paradox in the BEYOND trial.

BACKGROUND: The frequency and impact of neutralizing antibodies (NAbs) to interferon beta-1b (IFNß-1b) on clinical and radiographic outcomes is controversial. OBJECTIVE: To assess NAb impact in the BEYOND study. METHODS: 2244 patients were randomized (2:2:1) to receive IFNß-1b, either 250 or 500 µg, or glatiramer acetate, 20 mg, and observed for 2-3.5 years. NAb titers were determined every 6 months. A titer ≥20 NU/ml was considered NAb positive. Efficacy was compared between NAb-positive and NAb-negative patients, using comprehensive statistical analyses, taking into account the delayed appearance of NAbs, the time-dependent changes in the relapse rate, spontaneous reversions to NAb-negative status, NAb-titer level, and also adjusting for baseline factors. RESULTS: In the IFNß-1b 250 µg group, NAb-positive titers were detected (≥ once) in 319 patients (37.0%); of these, 112 (35.1%) reverted to NAb-negative status. In the IFNß-1b 500 µg group, 340 patients (40.7%) became NAb-positive and 119 (35.0%) reverted to NAb-negative status. In both IFNß groups, especially the 250 µg arm, NAb-positive status was not associated with a convincing impact on any clinical outcome measure by any statistical analysis. By contrast, in both IFNß groups, NAbs were associated with a very consistent deleterious impact on most MRI outcomes. CONCLUSION: There was a notable dissociation between the impact of NAbs on MRI and clinical outcomes. On MRI measures, the impact was consistent and convincing, whereas on clinical measures a negative impact of NAbs was not found. The basis for this clinico-radiographic paradox is unknown but it suggests that the relationship between NAbs and the therapeutic effects of IFNß-1b is complex.

Genome-wide meta-analysis identifies novel multiple sclerosis susceptibility loci.

OBJECTIVE: To perform a 1-stage meta-analysis of genome-wide association studies (GWAS) of multiple sclerosis (MS) susceptibility and to explore functional consequences of new susceptibility loci. METHODS: We synthesized 7 MS GWAS. Each data set was imputed using HapMap phase II, and a per single nucleotide polymorphism (SNP) meta-analysis was performed across the 7 data sets. We explored RNA expression data using a quantitative trait analysis in peripheral blood mononuclear cells (PBMCs) of 228 subjects with demyelinating disease. RESULTS: We meta-analyzed 2,529,394 unique SNPs in 5,545 cases and 12,153 controls. We identified 3 novel susceptibility alleles: rs170934(T) at 3p24.1 (odds ratio [OR], 1.17; p = 1.6 × 10(-8)) near EOMES, rs2150702(G) in the second intron of MLANA on chromosome 9p24.1 (OR, 1.16; p = 3.3 × 10(-8)), and rs6718520(A) in an intergenic region on chromosome 2p21, with THADA as the nearest flanking gene (OR, 1.17; p = 3.4 × 10(-8)). The 3 new loci do not have a strong cis effect on RNA expression in PBMCs. Ten other susceptibility loci had a suggestive p < 1 × 10(-6) , some of these loci have evidence of association in other inflammatory diseases (ie, IL12B, TAGAP, PLEK, and ZMIZ1). INTERPRETATION: We have performed a meta-analysis of GWAS in MS that more than doubles the size of previous gene discovery efforts and highlights 3 novel MS susceptibility loci. These and additional loci with suggestive evidence of association are excellent candidates for further investigations to refine and validate their role in the genetic architecture of MS.

Treatment of infantile spasms: emerging insights from clinical and basic science perspectives.

Infantile spasms is an epileptic encephalopathy of early infancy with specific clinical and electroencephalographic (EEG) features, limited treatment options, and a poor prognosis. Efforts to develop improved treatment options have been hindered by the lack of experimental models in which to test prospective therapies. The neuropeptide adrenocorticotropic hormone (ACTH) is effective in many cases of infantile spasms, although its mechanism(s) of action is unknown. This review describes the emerging candidate mechanisms that can underlie the therapeutic effects of ACTH in infantile spasms. These mechanisms can ultimately help to improve understanding and treatment of the disease. An overview of current treatments of infantile spasms, novel conceptual and experimental approaches to infantile spasms treatment, and a perspective on remaining clinical challenges and current research questions are presented here. This summary derives from a meeting of specialists in infantile spasms clinical care and research held in New York City on June 14, 2010.

Rapid immune responses to a botulinum neurotoxin Hc subunit vaccine through in vivo targeting to antigen-presenting cells.

The clostridial botulinum neurotoxins (BoNTs) are the most potent protein toxins known. The carboxyl-terminal fragment of the toxin heavy chain (Hc) has been intensively investigated as a BoNT vaccine immunogen. We sought to determine whether targeting Hc to antigen-presenting cells (APCs) could accelerate the immune responses to vaccination with BoNT serotype A (BoNT/A) Hc. To test this hypothesis, we targeted Hc to the Fc receptors for IgG (FcγRs) expressed by dendritic cells (DCs) and other APCs. Hc was expressed as a fusion protein with a recombinant ligand for human FcγRs (R4) to produce HcR4 or a similar ligand for murine FcγRs to produce HcmR4. HcR4, HcmR4, and Hc were produced as secreted proteins using baculovirus-mediated expression in SF9 insect cells. In vitro receptor binding assays showed that HcR4 effectively targets Hc to all classes of FcγRs. APCs loaded with HcR4 or HcmR4 are substantially more effective at stimulating Hc-reactive T cells than APCs loaded with nontargeted Hc. Mice immunized with a single dose of HcmR4 or HcR4 had earlier and markedly higher Hc-reactive antibody titers than mice immunized with nontargeted Hc. These results extend to BoNT neutralizing antibody titers, which are substantially higher in mice immunized with HcmR4 than in mice immunized with Hc. Our results demonstrate that targeting Hc to FcγRs augments the pace and magnitude of immune responses to Hc.

Olig1 is expressed in human oligodendrocytes during maturation and regeneration.

Myelin repair is inhibited in multiple sclerosis (MS), ultimately leading to axonal damage and disability. We aimed to understand the transcriptional mechanisms of regeneration in primary human oligodendrocyte cultures isolated from white matter of medically intractable epilepsy patients. Cultures at isolation contained 84% mature oligodendrocytes and 16% oligodendrocyte progenitor cells (OPC). The two populations showed a protracted regeneration of membranes expressing myelin proteins after 2-3 weeks in culture, and were kept long-term to study membranes maintenance. We profiled by quantitative PCR (qPCR) the sequential mRNA expression of transcription factors Olig1, Olig2, Nkx2.2, Sox10, PPARδ, PPARγ, cyclic nucleotide phosphodiesterase (CNP), myelin basic protein (MBP), myelin-associated glycoprotein (MAG) and myelin oligodendrocyte glycoprotein (MOG). In summary, Olig1 was not expressed in freshly isolated oligodendrocytes, but was expressed from the beginning of process extension until membranes maintenance. In contrast, Olig2 expression was restricted to isolation and during membranes production. We show for the first time PPARδ expression and absence of PPARγ in human oligodendrocytes. Nkx2.2, Sox10, PPARδ, CNP, MBP and MOG messengers were expressed at any time, while MAG messenger was expressed at mature stage only. Myelin proteins CNP, MBP, MAG, and MOG were confirmed by immunocytochemistry. Our findings point to different roles of Olig1 and Olig2 in regeneration of cultured adult human oligodendrocytes. Noticeably, the transcriptional profiles found in cultured neonatal rodent OPC are different. More studies are necessary to elucidate myelin repair in the adult human brain.

Immunoglobulin-like transcript 3, an inhibitor of T cell activation, is reduced on blood monocytes during multiple sclerosis relapses and is induced by interferon beta-1b.

Immunoglobulin-like transcripts (ILTs) are immunoregulatory proteins that either activate or inhibit immune responses. ILT3 is inhibitory and is expressed preferentially by antigen-presenting cells. When its extracellular domain binds to an unidentified ligand of activated T cells, the T cell is silenced. Our objective was to study the expression of ILT3 on circulating monocytes in RRMS. Freshly isolated peripheral blood mononuclear cells were analyzed by multicolored flow cytometry. The proportion of ILT3(+)CD14(+) monocytes in blood, and ILT3 levels expressed by them, is lower in untreated multiple sclerosis in relapse than in: (1) untreated multiple sclerosis in remission (p < 0.009); (2) stable interferon beta-treated relapsing-remitting multiple sclerosis (p < 0.001) and; (3) healthy controls (p < 0.009). Glatiramer acetate-stimulated CD4( +) T cells, co-cultured with freshly isolated monocytes, proliferate significantly better (p = 0.0017 for multiple sclerosis; p = 0.0015 for controls) when T cell interaction with monocyte-expressed ILT3 is blocked by anti-ILT3 antibody. Interferon beta is beneficial in multiple sclerosis; why so remains unclear. Interferon beta-1b markedly increases ILT3 expression in vitro by monocytes from multiple sclerosis patients and controls. These findings identify a putative novel mechanism for the therapeutic benefit bestowed by Interferon beta and a new target for therapeutic intervention in relapsing-remitting multiple sclerosis.

250 microg or 500 microg interferon beta-1b versus 20 mg glatiramer acetate in relapsing-remitting multiple sclerosis: a prospective, randomised, multicentre study.

BACKGROUND: The aim of the Betaferon Efficacy Yielding Outcomes of a New Dose (BEYOND) trial was to compare the efficacy, safety, and tolerability of 250 microg or 500 microg interferon beta-1b with glatiramer acetate for treating relapsing-remitting multiple sclerosis. METHODS: Between November, 2003, and June, 2005, 2447 patients with relapsing-remitting multiple sclerosis were screened and 2244 patients were enrolled in this prospective, multicentre, randomised trial. Patients were randomly assigned 2:2:1 by block randomisation with regional stratification to receive one of two doses of interferon beta-1b (250 microg or 500 microg) subcutaneously every other day or 20 mg glatiramer acetate subcutaneously every day. The primary outcome was relapse risk, defined as new or recurrent neurological symptoms separated by at least 30 days from the preceding event and that lasted at least 24 h. Secondary outcomes were progression on the expanded disability status scale (EDSS) and change in T1-hypointense lesion volume. Clinical outcomes were assessed quarterly for 2.0-3.5 years; MRI was done at screening and annually thereafter. Analysis was by per protocol. This study is registered, number NCT00099502. FINDINGS: We found no differences in relapse risk, EDSS progression, T1-hypointense lesion volume, or normalised brain volume among treatment groups. Flu-like symptoms were more common in patients treated with interferon beta-1b (p<0.0001), whereas injection-site reactions were more common in patients treated with glatiramer acetate (p=0.0005). Patient attrition rates were 17% (153 of 888) on 250 microg interferon beta-1b, 26% (227 of 887) on 500 microg interferon beta-1b, and 21% (93 of 445) for glatiramer acetate. INTERPRETATION: 500 microg interferon beta-1b was not more effective than the standard 250 microg dose, and both doses had similar clinical effects to glatiramer acetate. Although interferon beta-1b and glatiramer acetate had different adverse event profiles, the overall tolerability to both drugs was similar. FUNDING: Bayer HealthCare Pharmaceuticals.

Terbutaline in myasthenia gravis: a pilot study.

The objective of this study was to assess the short-term efficacy and safety of terbutaline, a beta2-adrenergic agonist, in patients with myasthenia gravis (MG) in a randomized, double-blind, placebo-controlled, crossover study. The primary endpoint for efficacy was a reduction of at least 3 points in the quantitative MG score (QMGS). Secondary endpoints included changes in the functional disability scale (FDS), forced vital capacity (FVC), grip strength, anti-acetylcholine receptor (AChR) antibody levels and decremental response. During the terbutaline phase, five of eight (63%) patients had an improvement in the QMGS of 3.0 or greater, while 3/8 (38%) patients had improvement in the FDS of one grade. No improvement was seen during the placebo period. Statistical analysis using Wilcoxon signed-rank test confirmed that terbutaline treatment resulted in a significant improvement in QMGS. There was no change in FVC, grip strength or anti-AChR antibody levels, but there was an improvement in the decremental response during terbutaline phase. Terbutaline was well-tolerated in all study subjects. We conclude that terbutaline may be an effective adjunct therapy in a subset of patients with myasthenia, although confirmation with larger trials will be required.

Tolerability and safety profile of 12- to 28-week treatment with interferon beta-1b 250 and 500 microg QOD in patients with relapsing-remitting multiple sclerosis: a multicenter, randomized, double-blind, parallel-group pilot study.

BACKGROUND: It is not known whether the currently available treatment regimen of interferon beta-1b (IFNbeta-1b) 250 microg provides the maximum benefit possible in the treatment of relapsing-remitting multiple sclerosis (RRMS), or whether higher doses of IFNbeta-1b will prove to be more beneficial. OBJECTIVE: The objective of the present study was to evaluate the tolerability and safety profile of IFNbeta-1b 500 microg compared with the currently approved 250-microg dose. METHODS: A multicenter, randomized, double-blind, parallel-group pilot study was carried out to compare IFNbeta-1b 250 microg with IFNbeta-1b 500 microg, both self-administered SC QOD for >or=12 weeks in patients with RRMS. Patients in both groups started with 25% (0.25 mL) of their final dose and were scheduled to increase the dose by 0.25 mL every 2 weeks, so that the full dose (1.0 mL, 250 microg or 500 microg) would be reached by week 7. The primary outcome measure was the percentage of patients experiencing each of the following adverse events (AEs): influenza-like symptoms (general term used to code the presence of >1 symptom typical of influenza), fever, myalgia, asthenia, headache, injection-site reactions, injection-site pain, or liver or hematologic abnormalities. All patients underwent a priori magnetic resonance imaging (MRI) with 0.1 mmol/kg gadolinium (Gd)-diethylenetriaminepentaacetic acid as contrast medium at screening and at week 12. MRI evaluation was included as a safety measure to monitor for excessive new disease not visible through clinical symptoms. RESULTS: Seventy-seven patients were assessed for inclusion in the study. Of these, 6 patients were screening failures and the remaining 71 were randomized to treatment (38-250 and 33-500 microg IFNbeta-1b). The uneven numbers in the groups were a consequence of the randomization process. Two patients in the 250-microg group (withdrawal of consent) and 1 in the 500-microg group (not completing follow-up visit) prematurely discontinued medication. The demographic characteristics were not significantly different between the 250-microg (n=38; mean [SD] age, 37.9 [8.3] years; weight, 83.5 [19.0] kg; height, 168.4 [9.3] cm) and 500-microg (n=33; mean [SD] age, 37.8 [7.7] years; weight, 82.3 [19.5] kg; height, 169.9 [10.5] cm) treatment groups. The patients in both groups were mostly white (87% and 73%, respectively). Baseline Expanded Disability Status Scale scores also were not significantly different between the 2 groups (mean [SD] score, 2.8 [1.4] vs 2.0 [1.4], respectively). In the IFN(2)-1b 250-microg group, 97% of the patients titrated to the full dose at some point during the course of the study, compared with 91% of the 500-microg group (P=NS). A dose-response effect was observed in some of the more frequent AEs (no. [%]) that included influenza-like syndrome (250-microg group, 13 [34] vs 500-microg group, 16 [48]), asthenia (13 [34] vs 16 [48], respectively), headache (12 [32] vs 12 [36]), myalgia (10 [26] vs 13 [39]), hypesthesia (10 [26] vs 11 [33]), nausea (6 [16] vs 8 [24]), paresthesia (6 [16] vs 8 [24]), myasthenia (4 [11] vs 8 [24]), chills (3 [8] vs 6 [18]), depression (3 [8] vs 5 [15]), back pain (2 [5] vs 5 [15]), increased liver enzymes (4 [11] vs 6 [18]), lymphopenia (4 [11] vs 3 [9]), fever (2 [5] vs 4 [12]), and pain in extremities (1 [3] vs 4 [12]). The between-group incidence of injection-site reactions was not significantly different. No new or unexpected AEs were recorded. Changes in MRI parameters between screening and 12 weeks were not significantly different between dose groups; these included median T2 lesion volume, median Gd-enhanced lesion volume, median Gd-enhanced lesion number, and mean number of newly active lesions. CONCLUSIONS: IFNbeta-1b 500 microg administered SC QOD was generally well tolerated in these patients with RRMS. Large, randomized controlled studies are needed to determine if there are significant differences in MRI end points between the 250- and 500-microg doses.

A novel Fc gamma receptor ligand augments humoral responses by targeting antigen to Fc gamma receptors.

Generating efficient antibody (Ab) responses against weak antigens remains challenging. Ab responses require antigen (Ag) uptake by antigen-presenting cells (APC), followed by presentation of processed Ag to T cells. Limited uptake of antigenic peptides by APC constrains Ab responses. Here we improve vaccine efficacy by targeting Ag to Fcgamma receptors (FcgammaR) using R4, a recombinant FcgammaR ligand. R4 has four repeats per chain of the hinge region and CH2 domain (HCH2) of human IgG1. HCH2 encompasses the FcgammaR binding site. The repeats are linked to the human IgG1 framework. To test R4 in augmenting Ag uptake, we expressed human serum albumin domain 1 (HSA1) at the N terminus of R4 to produce HSA1R4. HSA1R4 (50 microg) administered to mice in Ribi adjuvant induces up to 1100-fold higher HSA1-specific IgG titers than HSA1 (p<0.001). HSA1R4 (250 ng) induces up to 130 times more anti-HSA1 Ab than HSA1Fc, a protein with HSA1 linked to the IgG1 framework (p<0.001). HSA-reactive T cells proliferate more briskly to HSA1R4 than to HSA1Fc (p<0.008). Immunization with HSA1R4 yields greater T cell reactivity to HSA1 ex vivo than immunization with HSA1Fc (p<0.004). Linking antigenic peptides to linear HCH2 polymers may facilitate vaccine development.

Patterns and significance of concomitant central and peripheral inflammatory demyelination.

Inflammatory demyelinating diseases comprise a spectrum of disorders that affect central nervous system (CNS) and peripheral nervous system (PNS) myelin. Most individuals have demyelinating disease restricted to one or the other compartment but patients with concomitant CNS and PNS inflammatory inflammatory demyelinating processes have been reported not infrequently. In most such patients, involvement of either the CNS or the PNS predominates the clinical picture. Involvement of the other compartment is usually mild or subclinical with unclear prognostic and therapeutic implications. Similarly, while experimentally induced demyelinating disease in animal models is usually CNS or PNS predominant, varying degrees of pathology in the other system can occur depending on the species, type of immunogen, and genetic background of the immunized animal. When CNS and PNS demyelinating diseases occur concurrently, effective treatment for CNS disease can be safely combined with effective treatment for PNS disease.

Long-term experience with interferon beta-1b (Betaferon)in multiple sclerosis.

The interferon beta-1b (IFNbeta-1b, Betaferon/Betaseron) molecule was cloned some 20 years ago. In a pilot dose-finding trial involving 30 multiple sclerosis (MS) patients, the 10 MS patients receiving 250 microg (8 MIU) IFNbeta-1b every other day at 6 months showed a reduced attack frequency relative to 6 patients receiving placebo. Based on these extremely preliminary results a Phase III placebo-controlled trial was undertaken. Treatment with IFNbeta-1b was shown to reduce attack frequency and severity and to markedly reduce magnetic resonance imaging-(MRI) measured activity and disease burden. IFNbeta-1b therapy was subsequently shown to reduce MRI activity within 2 weeks of starting treatment. The benefits of treatment with IFNbeta-1b observed in the original pivotal study are maintained in the longer term, with consistent treatment effects seen after 5 years. IFNbeta-1b has subsequently been shown to reduce accumulation of disability in MS patients with early active secondary progressive disease, to increase cerebral metabolism, and to improve cognitive performance.IFNbeta-1b therapy is generally well tolerated. Classical systemic side effects related to all beta interferons can effectively be managed by dose escalation, and the use of an autoinjector minimises injection site reactions. About one-third of MS patients receiving IFNbeta-1b develop anti-interferon antibodies, typically within the first year of therapy. These antibodies have variable titres that fall with time and ultimately disappear in most patients. The clinical consequences of the presence of antibodies are presently unclear and inconsistent-some patients without antibodies respond poorly to treatment, whereas others with high-titre antibodies respond well to treatment. It is possible that immune complexes formed when anti-interferon antibodies encounter IFNbeta may enhance some of the immunomodulatory actions of the drug by improving CD8 cell-mediated suppressor function. Until the clinical relevance of antibodies is better understood, treatment decisions should be based on clinical grounds only.