Multiple Sclerosis: O'Connor PW

Polman CH, Reingold SC, Barkhof F, Calabresi PA, Clanet M, Cohen JA, Cutter GR, Freedman MS, Kappos L, Lublin FD, McFarland HF, Metz LM, Miller AE, Montalban X, O'Connor PW, Panitch H, Richert JR, Petkau J, Schwid SR, Sormani MP, Thompson AJ, Weinshenker BG, Wolinsky JS. · Department of Neurology, Free University Medical Center in Amsterdam, PO Box 4075, 1007 MB Amsterdam, The Netherlands. · Neurology. · Pubmed #18362273 No free full text.

Abstract: The increasing number of established effective therapies for relapsing multiple sclerosis (MS) and emerging consensus for early treatment raise practical concerns and ethical dilemmas for placebo-controlled clinical trials in this disease. An international group of clinicians, ethicists, statisticians, regulators, and representatives from the pharmaceutical industry convened to reconsider prior recommendations regarding the ethics of placebo-controlled trials in MS. The group concluded that placebo-controlled trials can still be done ethically, with restrictions. For patients with relapsing MS for which established effective therapies exist, placebo-controlled trials should only be offered with rigorous informed consent if the subjects refuse to use these treatments, have not responded to them, or if these treatments are not available to them for other reasons (e.g., economics). Suggestions are provided to protect subject autonomy and improve informed consent procedures. Recommendations are tighter than previously suggested for placebo-controlled trials in "resource-restricted" environments where established therapies may not be available. Guidance is also provided on the ethics of alternative trial designs and the balance between study subject burden and risk, scientific rationale and interpretability of trial outcomes.

Kappos L, Bates D, Hartung HP, Havrdova E, Miller D, Polman CH, Ravnborg M, Hauser SL, Rudick RA, Weiner HL, O'Connor PW, King J, Radue EW, Yousry T, Major EO, Clifford DB. · University Hospital, Basel, Switzerland. · Lancet Neurol. · Pubmed #17434098 No free full text.

Abstract: Natalizumab is a new treatment option for patients with active relapsing-remitting multiple sclerosis. In phase III studies, natalizumab was highly effective and well tolerated; however, three cases of progressive multifocal leucoencephalopathy (PML) were identified (estimated incidence of one per 1000; 95% CI 0.2-2.8; mean treatment period 17.9 months). In this Review we summarise the current information on PML, the three confirmed cases of PML, and the results of an extensive safety assessment of all patients treated with natalizumab. On the basis of these reviews, we make recommendations for appropriate selection of candidates for natalizumab and pretreatment assessments. In addition, a three-step diagnostic and management algorithm was developed to monitor natalizumab-treated patients with multiple sclerosis for PML and other opportunistic infections. The algorithm includes strategies for clinical, MRI, and laboratory assessments. Maintaining clinical vigilance allows for early suspension of natalizumab in potential cases of PML, thereby increasing the opportunity for immune reconstitution, which may improve prognosis if PML is confirmed.

Polman CH, Reingold SC, Edan G, Filippi M, Hartung HP, Kappos L, Lublin FD, Metz LM, McFarland HF, O'Connor PW, Sandberg-Wollheim M, Thompson AJ, Weinshenker BG, Wolinsky JS. · VU Medical Center Amsterdam, Free University, PO Box 7057, 1007 MB Amsterdam, the Netherlands. · Ann Neurol. · Pubmed #16283615 No free full text.

Abstract: New diagnostic criteria for multiple sclerosis integrating magnetic resonance image assessment with clinical and other paraclinical methods were introduced in 2001. The "McDonald Criteria" have been extensively assessed and used since 2001. New evidence and consensus now strengthen the role of these criteria in the multiple sclerosis diagnostic workup to demonstrate dissemination of lesions in time, to clarify the use of spinal cord lesions, and to simplify diagnosis of primary progressive disease. The 2005 Revisions to the McDonald Diagnostic Criteria for MS should simplify and speed diagnosis, whereas maintaining adequate sensitivity and specificity.

Ursell MR, O'Connor PW. · University of Toronto, Toronto, Ontario, Canada. · Neurol Clin. · Pubmed #15661096 No free full text.

This publication has no abstract.

Bril V, Allenby K, Midroni G, O'Connor PW, Vajsar J. · Division of Neurology, Toronto Hospital, Ontario, Canada. · Can J Neurol Sci. · Pubmed #10352875 No free full text.

Abstract: OBJECTIVE: To summarize the evidence for neurologic uses of immunoglobulin, intravenous (IGIV) in light of present-day clinical usage. This summary guided the development of practice recommendations for the effective and efficient use of IGIV in Neurology. METHODS: MEDLINE was searched to identify pertinent English-language review articles and original reports (n = 231) on the use of IGIV in neurology (excluding editorials, letters, and comments) published before March 1998. Evidence on alternative therapies was only included as compared to IGIV. The relevant original reports and review articles and older classic studies (n = 92) were synthesized into an information foundation. Extracted data included laboratory and clinical findings, objective measures, and clinical impressions. Clinical recommendations were based on evidence quality, graded by study design, clinical experiences of IGIV in Neurology Advisory Board members, and the conditions of IGIV use in therapy. RESULTS AND CONCLUSIONS: In neurology, many disorders are poorly understood, and the mechanisms behind beneficial regimens even less so. As a result, it is fairly common for best-practice decisions to rest on weaker evidence. The usefulness of IGIV in neurology can be described by a "combined score" based on evidence quality and strength of impact. Combined scores ranged from A+ (strongly recommended) to C (recommended as a last resort). The following clinical recommendations are made: IGIV is: strongly recommended for the treatment of Guillain-Barré syndrome (A+); favorably recommended for the treatment of chronic inflammatory demyelinating polyradiculoneuropathy, dermatomyositis, and multifocal motor neuropathy (A); recommended as a second resort for the treatment of multiple sclerosis and myasthenia gravis (B); and recommended as a last resort for the treatment of polymyositis, inclusion-body myositis, intractable epilepsies, and stiff-man syndrome (C).

Havrdova E, Galetta S, Hutchinson M, Stefoski D, Bates D, Polman CH, O'Connor PW, Giovannoni G, Phillips JT, Lublin FD, Pace A, Kim R, Hyde R. · Charles University in Prague, Department of Neurology, First Faculty of Medicine, Prague, Czech Republic. · Lancet Neurol. · Pubmed #19201654 No free full text.

Abstract: BACKGROUND: The efficacy of natalizumab on clinical and radiological measures in the phase III Natalizumab Safety and Efficacy in Relapsing-Remitting Multiple Sclerosis (AFFIRM) study has prompted the investigation of whether natalizumab can increase the proportion of patients with relapsing-remitting multiple sclerosis who do not have disease activity. METHODS: Post-hoc analyses of data from the AFFIRM study were done to determine the effects of natalizumab compared with placebo on the proportion of patients who were free of disease activity over 2 years. Absence of disease activity was defined as no activity on clinical measures (no relapses and no sustained disability progression), radiological measures (no gadolinium-enhancing lesions and no new or enlarging T2-hyperintense lesions on cranial MRI), or a composite of the two. FINDINGS: 383 (64%) of 596 patients taking natalizumab and 117 (39%) of 301 taking placebo were free of clinical disease activity (absolute difference 25.4%, 95% CI 18.7-32.1%, p<0.0001); 342 (58%) of 593 and 42 (14%) of 296 were free of radiological disease activity (43.5%, 37.9-49.1%, p<0.0001); and 220 (37%) of 600 and 22 (7%) of 304 were free of combined activity (29.5%, 24.7-34.3%, p<0.0001) over 2 years. The effect of natalizumab versus placebo was consistent across subgroups of patients with highly active or non-highly active disease at baseline. INTERPRETATION: Disease remission might become an increasingly attainable goal in multiple sclerosis treatment with the use of newer, more effective therapies.

Miller DH, Soon D, Fernando KT, MacManus DG, Barker GJ, Yousry TA, Fisher E, O'Connor PW, Phillips JT, Polman CH, Kappos L, Hutchinson M, Havrdova E, Lublin FD, Giovannoni G, Wajgt A, Rudick R, Lynn F, Panzara MA, Sandrock AW, Anonymous00097. · Institute of Neurology, University College London, London, UK. · Neurology. · Pubmed #17452584 No free full text.

Abstract: BACKGROUND: In a 2-year, placebo-controlled trial (the Natalizumab Safety and Efficacy in Relapsing Remitting Multiple Sclerosis [AFFIRM] study), involving 942 patients with relapsing multiple sclerosis (MS), natalizumab significantly reduced the relapse rate by 68% and progression of sustained disability by 42% vs placebo. We report the effect of natalizumab on MRI measures from the AFFIRM study. METHODS: The number and volume of gadolinium (Gd)-enhancing, new or enlarging T2-hyperintense, and new T1-hypointense lesions and brain parenchymal fraction were measured from annual scans obtained at baseline, 1 year, and 2 years. RESULTS: Compared with placebo, natalizumab produced a 92% decrease in Gd-enhancing lesions (means 2.4 vs 0.2; p < 0.001), an 83% decrease in new or enlarging T2-hyperintense lesions (means 11.0 vs 1.9; p < 0.001), and a 76% decrease in new T1-hypointense lesions (means 4.6 vs 1.1; p < 0.001) over 2 years. Median T2-hyperintense lesion volume increased by 8.8% in the placebo group and decreased by 9.4% in the natalizumab group (p < 0.001); median T1-hypointense lesion volume decreased by 1.5% in the placebo group and decreased by 23.5% in the natalizumab group (p < 0.001). Brain atrophy was greater in year 1 and less in year 2 in natalizumab-treated patients. CONCLUSION: Natalizumab has a sustained effect in preventing the formation of new lesions in patients with relapsing multiple sclerosis.

Balcer LJ, Galetta SL, Calabresi PA, Confavreux C, Giovannoni G, Havrdova E, Hutchinson M, Kappos L, Lublin FD, Miller DH, O'Connor PW, Phillips JT, Polman CH, Radue EW, Rudick RA, Stuart WH, Wajgt A, Weinstock-Guttman B, Wynn DR, Lynn F, Panzara MA. · Department of Neurology, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA. · Neurology. · Pubmed #17438220 No free full text.

Abstract: OBJECTIVE: To examine the effects of natalizumab on low-contrast letter acuity as a prespecified tertiary endpoint in two randomized clinical trials and to evaluate the usefulness of low-contrast letter acuity testing as a candidate test of visual function in multiple sclerosis (MS). METHODS: AFFIRM and SENTINEL were randomized, double-blind, placebo-controlled, multicenter, phase 3 clinical trials of natalizumab in relapsing MS. Natalizumab was evaluated as monotherapy in AFFIRM and as add-on to interferon beta-1a in SENTINEL. Vision testing was performed at 100% contrast (visual acuity) and low-contrast (2.5% and 1.25%). RESULTS: The risk of clinically significant visual loss (predefined as a two-line worsening of acuity sustained over 12 weeks) at the lowest contrast level (1.25%) was reduced in the natalizumab treatment arms by 35% in AFFIRM (hazard ratio = 0.65; 95% CI: 0.47 to 0.90; p = 0.008) and by 28% in SENTINEL (hazard ratio = 0.72; 95% CI: 0.54 to 0.98; p = 0.038, Cox proportional hazards models). Mean changes in vision scores from baseline were also significantly different, reflecting worsening in non-natalizumab groups. CONCLUSIONS: Natalizumab reduces visual loss in patients with relapsing multiple sclerosis. Low-contrast acuity testing has the capacity to demonstrate treatment effects and is a strong candidate for assessment of visual outcomes in future multiple sclerosis trials.

Phillips JT, O'Connor PW, Havrdova E, Hutchinson M, Kappos L, Miller DH, Polman CH, Lublin FD, Giovannoni G, Wajgt A, Lynn F, Panzara MA, Sandrock AW, Anonymous00379. · Multiple Sclerosis Center at Texas Neurology, Dallas, TX 75214, USA. · Neurology. · Pubmed #17101921 No free full text.

This publication has no abstract.

O'Connor PW, Li D, Freedman MS, Bar-Or A, Rice GP, Confavreux C, Paty DW, Stewart JA, Scheyer R, Anonymous00137, Anonymous00138. · University of Toronto, Ontario, Canada. · Neurology. · Pubmed #16567708 No free full text.

Abstract: BACKGROUND: Teriflunomide, a dihydro-orotate dehydrogenase inhibitor, has immunomodulatory effects, including the ability to suppress experimental allergic encephalomyelitis. In this randomized, double-blind, placebo-controlled Phase II study, the authors examined the safety and efficacy of oral teriflunomide in multiple sclerosis (MS) with relapses. METHODS: Patients (n = 179) with relapsing-remitting MS (n = 157) or secondary progressive MS with relapses (n = 22) were randomized to receive placebo, teriflunomide 7 mg/day, or teriflunomide 14 mg/day for 36 weeks. MRI brain scans were performed every 6 weeks. The primary endpoint was the number of combined unique active lesions per MRI scan. Secondary endpoints included MRI-defined disease burden, relapse frequency, and disability increase. RESULTS: The median number of combined unique active lesions per scan was 0.5, 0.2, and 0.3 in the placebo, teriflunomide 7 mg/day (p < 0.03 vs placebo), and teriflunomide 14 mg/day (p < 0.01 vs placebo) groups during the 36-week double-blind treatment phase. Teriflunomide-treated patients also had significantly fewer T1 enhancing lesions per scan, new or enlarging T2 lesions per scan, and new T2 lesions. Patients receiving teriflunomide 14 mg/day had significantly reduced T2 disease burden. Teriflunomide treatment resulted in trends toward a lower annualized relapse rate and fewer relapsing patients (14 mg/day only) vs placebo. Significantly fewer patients receiving teriflunomide 14 mg/day vs placebo demonstrated disability increase. Treatment was well tolerated; numbers of adverse events and serious adverse events were similar in all treatment groups. CONCLUSION: Oral teriflunomide was effective in reducing MRI lesions and was well tolerated in patients with relapsing multiple sclerosis.

Polman CH, O'Connor PW, Havrdova E, Hutchinson M, Kappos L, Miller DH, Phillips JT, Lublin FD, Giovannoni G, Wajgt A, Toal M, Lynn F, Panzara MA, Sandrock AW, Anonymous00010. · Vrije Universiteit Medical Center, Amsterdam, The Netherlands. · N Engl J Med. · Pubmed #16510744 links to  free full text

Abstract: BACKGROUND: Natalizumab is the first alpha4 integrin antagonist in a new class of selective adhesion-molecule inhibitors. We report the results of a two-year phase 3 trial of natalizumab in patients with relapsing multiple sclerosis. METHODS: Of a total of 942 patients, 627 were randomly assigned to receive natalizumab (at a dose of 300 mg) and 315 to receive placebo by intravenous infusion every four weeks for more than two years. The primary end points were the rate of clinical relapse at one year and the rate of sustained progression of disability, as measured by the Expanded Disability Status Scale, at two years. RESULTS: Natalizumab reduced the risk of sustained progression of disability by 42 percent over two years (hazard ratio, 0.58; 95 percent confidence interval, 0.43 to 0.77; P<0.001). The cumulative probability of progression (on the basis of Kaplan-Meier analysis) was 17 percent in the natalizumab group and 29 percent in the placebo group. Natalizumab reduced the rate of clinical relapse at one year by 68 percent (P<0.001) and led to an 83 percent reduction in the accumulation of new or enlarging hyperintense lesions, as detected by T2-weighted magnetic resonance imaging (MRI), over two years (mean numbers of lesions, 1.9 with natalizumab and 11.0 with placebo; P<0.001). There were 92 percent fewer lesions (as detected by gadolinium-enhanced MRI) in the natalizumab group than in the placebo group at both one and two years (P<0.001). The adverse events that were significantly more frequent in the natalizumab group than in the placebo group were fatigue (27 percent vs. 21 percent, P=0.048) and allergic reaction (9 percent vs. 4 percent, P=0.012). Hypersensitivity reactions of any kind occurred in 25 patients receiving natalizumab (4 percent), and serious hypersensitivity reactions occurred in 8 patients (1 percent). CONCLUSIONS: Natalizumab reduced the risk of the sustained progression of disability and the rate of clinical relapse in patients with relapsing multiple sclerosis. Adhesion-molecule inhibitors hold promise as an effective treatment for relapsing multiple sclerosis. (ClinicalTrials.gov number, NCT00027300.).

O'Connor PW, Goodman A, Willmer-Hulme AJ, Libonati MA, Metz L, Murray RS, Sheremata WA, Vollmer TL, Stone LA, Anonymous00089. · St. Michael's Hospital, Toronto, Ontario, Canada. · Neurology. · Pubmed #15184611 No free full text.

Abstract: BACKGROUND: Relapses in multiple sclerosis (MS) can cause significant neurologic disability. Natalizumab (Antegren) is a humanized anti-alpha4-integrin antibody that inhibits the trafficking of leukocytes across endothelium by blocking binding of alpha4beta1-integrin to vascular cell adhesion molecule-1. OBJECTIVE: To assess the effects of a single dose of IV natalizumab administered soon after the onset of MS relapses. METHODS: In this randomized, double-blind, multicenter trial, the effects of a single dose of IV natalizumab administered soon after the onset of MS relapses were assessed. MS patients (n = 180) in acute relapse were randomly assigned to receive a single dose of natalizumab 1 or 3 mg/kg or placebo and were followed for 14 weeks. RESULTS: There was no difference in Expanded Disability Status Scale (EDSS) score change over time between treatment and placebo groups. In all three groups, approximately half of patients showed EDSS improvement after 2 weeks, rising to 67% by 8 weeks. EDSS improved by a mean value of 0.8 point at week 1, 1.2 points at week 4, and 1.6 points at week 8 in the natalizumab group compared with EDSS improvement of 1.0 point at week 1, 1.6 points at week 4, and 1.6 points at week 8 in the placebo group. A significant decrease in Gd-enhancing lesion volume was seen in both active treatment groups at weeks 1 and 3 compared with placebo. CONCLUSIONS: A single dose of IV natalizumab did not hasten clinical recovery after relapse, although a significant decrease in Gd-enhancing lesion volume was observed at 1 and 3 weeks after treatment. These MRI findings are consistent with prior studies of natalizumab and support its further investigation as an agent for the treatment of MS.

Miller DH, Khan OA, Sheremata WA, Blumhardt LD, Rice GP, Libonati MA, Willmer-Hulme AJ, Dalton CM, Miszkiel KA, O'Connor PW, Anonymous00142. · Department of Neuroinflammation, Institute of Neurology, London, United Kingdom. · N Engl J Med. · Pubmed #12510038 links to  free full text

Abstract: BACKGROUND: In patients with multiple sclerosis, inflammatory brain lesions appear to arise from autoimmune responses involving activated lymphocytes and monocytes. The glycoprotein alpha4 integrin is expressed on the surface of these cells and plays a critical part in their adhesion to the vascular endothelium and migration into the parenchyma. Natalizumab is an alpha4 integrin antagonist that reduced the development of brain lesions in experimental models and in a preliminary study of patients with multiple sclerosis. METHODS: In a randomized, double-blind trial, we randomly assigned a total of 213 patients with relapsing-remitting or relapsing secondary progressive multiple sclerosis to receive 3 mg of intravenous natalizumab per kilogram of body weight (68 patients), 6 mg per kilogram (74 patients), or placebo (71 patients) every 28 days for 6 months. The primary end point was the number of new brain lesions on monthly gadolinium-enhanced magnetic resonance imaging during the six-month treatment period. Clinical outcomes included relapses and self-reported well-being. RESULTS: There were marked reductions in the mean number of new lesions in both natalizumab groups: 9.6 per patient in the placebo group, as compared with 0.7 in the group given 3 mg of natalizumab per kilogram (P<0.001) and 1.1 in the group given 6 mg of natalizumab per kilogram (P<0.001). Twenty-seven patients in the placebo group had relapses, as compared with 13 in the group given 3 mg of natalizumab per kilogram (P=0.02) and 14 in the group given 6 mg of natalizumab per kilogram (P=0.02). The placebo group reported a slight worsening in well-being (a mean decrease of 1.38 mm on a 100-mm visual-analogue scale), whereas the natalizumab groups reported an improvement (mean increase of 9.49 mm in the group given 3 mg of natalizumab per kilogram and 6.21 mm in the group given 6 mg of natalizumab per kilogram). CONCLUSIONS: In a placebo-controlled trial, treatment with natalizumab led to fewer inflammatory brain lesions and fewer relapses over a six-month period in patients with relapsing multiple sclerosis.

Burton JM, O'Connor PW, Hohol M, Beyene J. · Division of Neurology, St. Michael's Hospital, 30 Bond Street, Toronto, Ontario, Canada, M5B 1W8. · Cochrane Database Syst Rev. · Pubmed #19588409 No free full text.

Abstract: BACKGROUND: Multiple Sclerosis (MS), a chronic inflammatory and neurodegenerative disease of the central nervous system (CNS), is characterized by recurrent relapses of CNS inflammation ranging from mild to severely disabling. Relapses have long been treated with steroids to reduce inflammation and hasten recovery. However, the commonly used intravenous methylprednisolone requires repeated infusions with the added costs of homecare or hospitalization, and may interfere with daily responsibilities. Oral steroids have been used in place of intravenous steroids, with lower direct and indirect costs. OBJECTIVES: The primary objective was to compare efficacy of oral versus intravenous steroids for MS relapses <= 6 weeks. Secondary comparisons included subsequent relapse rate, disability, ambulation, hospitalization, immunological markers, radiological markers, and quality of life. SEARCH STRATEGY: A literature search was performed using Cochrane MS Group Trials Register (July 2008), Cochrane Central Register of Controlled Trials (CENTRAL) "The Cochrane Library 2008, issue 3, MEDLINE (PubMed) (1966-July 2008), EMBASE (1980-July 2008), abstracts from meetings of the American Academy of Neurology (2002-2008), the European Federation of Neurological Sciences (2002-2008), the European Committee for Treatment and Research in Multiple Sclerosis and American Committee for Treatment and Research in Multiple Sclerosis (2002-2008) handsearching. No language restrictions were applied. SELECTION CRITERIA: Randomized or quasi-randomized trials comparing oral and intravenous steroids for acute relapses (<=30 days) in clinically definite MS patients over age 16 were eligible. DATA COLLECTION AND ANALYSIS: Methodological was assessed using trial publications and personal communication. Elevant data was extracted, and effect size was reported as mean difference (MD),weighted mean difference (WMD), odds ratio (OR) and absolute risk difference (ARD). MAIN RESULTS: Eligible studies (167 patients) were identified. Only one outcome, the proportion of patients with EDSS improvement at 4 weeks, was common to three trials. Otherwise outcomes were too heterogeneous to pool. Only one trial employed an equivalence design, but all reported no statistically significant difference in outcomes between groups. Namely, there was no significant difference in the degree of recovery 4 weeks following treatment. No difference was found in subsequent relapse rate, disability, hospitalization, ambulation, bioavailability, or in magnetic resonance imaging (MRI). Due to methodological limitations, heterogeneous treatment regimens and limited data, formal conclusions about equivalence of oral and intravenous steroidscannot be made. Oral Megadose Corticosteroid Therapy of Acute Exacerbations of Multiple Sclerosis (OMEGA) trial, designed to address such limitations, is currently underway. AUTHORS' CONCLUSIONS: The trials reviewed support the hypothesis that no significant differences in clinical, radiological or pharmacological outcomes oral and intravenous steroids for MS relapses exist. However, with the small number of patients and methodological limitations, conclusions of equivalence are premature.

Hutchinson M, Kappos L, Calabresi PA, Confavreux C, Giovannoni G, Galetta SL, Havrdova E, Lublin FD, Miller DH, O'Connor PW, Phillips JT, Polman CH, Radue EW, Rudick RA, Stuart WH, Wajgt A, Weinstock-Guttman B, Wynn DR, Lynn F, Panzara MA, Anonymous00112. · Dept. of Neurology, St. Vincent's University Hospital, Dublin, Ireland. · J Neurol. · Pubmed #19308305 No free full text.

Abstract: The AFFIRM and SENTINEL studies showed that natalizumab was effective both as monotherapy and in combination with interferon beta (IFNbeta)-1a in patients with relapsing multiple sclerosis (MS). Further analyses of AFFIRM and SENTINEL data were conducted to determine the efficacy of natalizumab in prespecified patient subgroups according to baseline characteristics: relapse history 1 year before randomization (1, 2, > or = 3), Expanded Disability Status Scale score (< or = 3.5, > 3.5), number of T2 lesions (< 9, > or = 9), presence of gadolinium-enhancing (Gd+) lesions (0, > or = 1), age (< 40, > or = 40) and gender (male, female). A post hoc analysis was conducted to determine the efficacy of natalizumab in patients with highly active disease (i. e., > or = 2 relapses in the year before study entry and > or = 1 Gd+ lesion at study entry). In both AFFIRM and SENTINEL studies natalizumab reduced the annualized relapse rates across all subgroups (except the small subgroups with < 9 baseline T2 lesions) over 2 years. In AFFIRM, natalizumab significantly reduced the risk of sustained disability progression in most subgroups. In SENTINEL, natalizumab significantly reduced the risk of sustained disability progression in the following subgroups: > or = 9 T2 lesions at baseline, > or = 1 Gd+ lesions at baseline, female patients and patients < 40 years of age. Natalizumab reduced the risk of disability progression by 64 % and relapse rate by 81 % in treatment- naive patients with highly active disease and by 58 % and 76 %, respectively, in patients with highly active disease despite IFNbeta-1a treatment. These results indicate that natalizumab is effective in reducing disability progression and relapses in patients with relapsing MS, particularly in patients with highly active disease.

Burton JM, Bell CM, Walker SE, O'Connor PW. · Division of Neurology, St. Michael's Hospital, 30 Bond St., Toronto, Ontario, M5B 1W8, Canada. · Neurology. · Pubmed #19029525 No free full text.

This publication has no abstract.

Calabresi PA, Giovannoni G, Confavreux C, Galetta SL, Havrdova E, Hutchinson M, Kappos L, Miller DH, O'Connor PW, Phillips JT, Polman CH, Radue EW, Rudick RA, Stuart WH, Lublin FD, Wajgt A, Weinstock-Guttman B, Wynn DR, Lynn F, Panzara MA, Anonymous00406. · Johns Hopkins Multiple Sclerosis Center, Baltimore, MD, USA. · Neurology. · Pubmed #17761550 No free full text.

Abstract: OBJECTIVE: To determine the incidence and clinical effects of antibodies that develop during treatment with natalizumab. METHODS: In two randomized, double-blind, placebo-controlled studies (natalizumab safety and efficacy in relapsing remitting multiple sclerosis [MS, AFFIRM] and safety and efficacy of natalizumab in combination with interferon beta-1a [INF beta]1a] in patients with relapsing remitting MS [SENTINEL]) of patients with relapsing multiple sclerosis, blood samples were obtained at baseline and every 12 weeks to determine the presence of antibodies against natalizumab. Antibodies to natalizumab were measured using an ELISA. Patients were categorized as "transiently positive" if they had detectable antibodies (>or=0.5 microg/mL) at a single time point or "persistently positive" if they had antibodies at two or more time points >or=6 weeks apart. RESULTS: In the AFFIRM study, antibodies were detected in 57 of 625 (9%) of natalizumab-treated patients: Twenty (3%) were transiently positive and 37 (6%) were persistently positive. Persistently positive patients showed a loss of clinical efficacy as measured by disability progression (p <or= 0.05), relapse rate (p = 0.009), and MRI (p <or= 0.05) compared with antibody-negative patients. In transiently positive patients, full efficacy was achieved after approximately 6 months of treatment, the time when patients were becoming antibody negative. The incidence of infusion-related adverse events was significantly higher in persistently positive patients. Results of SENTINEL were similar to AFFIRM, except with regard to sustained disability progression; differences between persistently positive and antibody-negative patients were not statistically significant. CONCLUSIONS: The incidence of persistent antibody positivity associated with natalizumab is 6%. Reduced clinical efficacy is apparent in persistently positive patients. Patients with a suboptimal clinical response or persistent infusion-related adverse events should be considered for antibody testing.

Rudick RA, Miller D, Hass S, Hutchinson M, Calabresi PA, Confavreux C, Galetta SL, Giovannoni G, Havrdova E, Kappos L, Lublin FD, Miller DH, O'Connor PW, Phillips JT, Polman CH, Radue EW, Stuart WH, Wajgt A, Weinstock-Guttman B, Wynn DR, Lynn F, Panzara MA, Anonymous00338. · Department of Neurology, Mellen Center for Multiple Sclerosis Treatment and Research, Cleveland Clinic Foundation, Cleveland, OH 44195, USA. · Ann Neurol. · Pubmed #17696126 No free full text.

Abstract: OBJECTIVE: To report the relationship between disease activity and health-related quality of life (HRQoL) in relapsing multiple sclerosis, and the impact of natalizumab. METHODS: HRQoL data were available from 2,113 multiple sclerosis patients in natalizumab clinical studies. In the Natalizumab Safety and Efficacy in Relapsing Remitting Multiple Sclerosis (AFFIRM) study, patients received natalizumab 300 mg (n = 627) or placebo (n = 315); in the Safety and Efficacy of Natalizumab in Combination with Interferon Beta-1a in Patients with Relapsing Remitting Multiple Sclerosis (SENTINEL) study, patients received interferon beta-1a (IFN-beta-1a) plus natalizumab 300 mg (n = 589), or IFN-beta-1a plus placebo (n = 582). The Short Form-36 (SF-36) and a subject global assessment visual analog scale were administered at baseline and weeks 24, 52, and 104. Prespecified analyses included changes from baseline to week 104 in SF-36 and visual analog scale scores. Odds ratios for clinically meaningful improvement or worsening on the SF-36 Physical Component Summary (PCS) and Mental Component Summary were calculated. RESULTS: Mean baseline SF-36 scores were significantly less than the general US population and correlated with Expanded Disability Status Scale scores, sustained disability progression, relapse number, and increased volume of brain magnetic resonance imaging lesions. Natalizumab significantly improved SF-36 PCS and Mental Component Summary scores at week 104 in AFFIRM. PCS changes were significantly improved by week 24 and at all subsequent time points. Natalizumab-treated patients in both studies were more likely to experience clinically important improvement and less likely to experience clinically important deterioration on the SF-36 PCS. The visual analog scale also showed significantly improved HRQoL with natalizumab. INTERPRETATION: HRQoL was impaired in relapsing multiple sclerosis patients, correlated with severity of disease as measured by neurological ratings or magnetic resonance imaging, and improved significantly with natalizumab.

Chen JT, Kuhlmann T, Jansen GH, Collins DL, Atkins HL, Freedman MS, O'Connor PW, Arnold DL, Anonymous00288. · McConnell Brain Imaging Centre, Montreal Neurological Institute and Hospital, Montreal, Canada H3A 2B4. · Neuroimage. · Pubmed #17543541 No free full text.

Abstract: We present a new method for advanced image processing to separately quantify significant decreases and increases in the magnetization transfer ratio (MTR) of individual voxels of MS lesions as markers of demyelination and remyelination. We used this method to analyze the evolution of MTR in individual voxels of an acute, Gadolinium (Gd)-enhancing lesion that was available for pathology. Over 6.5 months following enhancement, MTR was low and stable in the lesion center (81% of the initially Gd-enhancing lesion volume (GdLV)) and MTR increased at the lesion border with normal-appearing white matter (14%GdLV). The estimated error of these measurements was less than 1.8%GdLV based on scan/rescan analysis. Histopathological analysis confirmed a demyelinated lesion centre with diffuse presence of macrophages/microglia and marked loss of oligodendrocytes and a partially remyelinated lesion border with diffuse presence of macrophages/microglia and relatively more oligodendrocytes compared to the lesion centre. The correlation of imaging and histopathological findings support the validity and sensitivity of our method of voxel-based MTR image processing for monitoring demyelination and remyelination in vivo.

Dalton CM, Miszkiel KA, O'Connor PW, Plant GT, Rice GP, Miller DH. · Institute of Neurology, London, UK. · Neurology. · Pubmed #16534105 No free full text.

Abstract: OBJECTIVES: To investigate ventricular enlargement (VE) over 1 year at three different stages of multiple sclerosis (MS). METHODS: A semi-automated technique for measuring VE was applied to MRI scans in 26 patients with clinically isolated syndromes (CIS) suggestive of MS, 30 with early relapse-onset MS of 1 year duration, 41 with established relapsing remitting (RR) MS, and 23 with secondary progressive (SP) MS. RESULTS: VE at 1 year was seen in early MS (median increase 0.3 mL [p = 0.003]), RRMS (median increase 0.5 mL [p = 0.001]), and SPMS (median increase 1.1 mL [p = 0.001]). Allowing for age there was more VE in the SPMS group (p = 0.005). No VE was observed in the CIS only group (median decrease -0.001 mL [p = 0.829]). Significant increases in T2 and T1 hypointense lesion load volume were seen in all MS subgroups: there were no differences between the groups in T2 volume increase but there was a larger increase in T1 hypointense lesion volume in the SPMS group compared with early RRMS. CONCLUSIONS: Ventricular enlargement is a sensitive measure of progressive cerebral atrophy that is seen at all stages of multiple sclerosis (MS) and is more marked in secondary progressive than relapsing remitting MS.

Kalia LV, O'Connor PW. · Department of Neurology, University of Toronto, Ontario M5B 1W8, Canada. · Mult Scler. · Pubmed #15957515 No free full text.

Abstract: INTRODUCTION: This study used reliable and validated instruments to compare pain severity in multiple sclerosis (MS) to that in other chronic painful conditions, and to examine relationships between chronic pain in MS and health-related quality of life (HRQOL). METHODS: Ninety-nine MS patients completed a self-administered survey comprised of the Medical Outcomes 36-Item Short-Form Health Survey, the Short-Form McGill Pain Questionnaire, and the Hospital Anxiety and Depression Scale. RESULTS: Pain severity was not different between MS patients with pain and rheumatoid arthritis (P = 0.77) or osteoarthritis (P = 0.98) patients. Chronic pain in MS was less often neurogenic than non-neurogenic, although severity of neurogenic pain was greater than that of non-neurogenic pain (P = 0.048). Chronic pain in MS was found to have no significant relationship to age, disease duration or disease course. Instead, we found that pain was correlated with aspects of HRQOL, particularly mental health (r = 0.44, P < 0.0001) versus physical functioning (r = 0.19, P > 0.05). Chronic pain was significantly related to anxiety and depression for females but not for males with MS. CONCLUSIONS: Chronic pain in MS is as severe as pain in arthritic conditions and is associated with reduced HRQOL. Thus, pain can be a significant symptom for MS patients and the need for treatment may be underestimated.

O'Connor PW. · Division of Neurology, St. Michael's Hospital, Toronto, Ont. · CMAJ. · Pubmed #11216206 links to  free full text

This publication has no abstract.

Winer S, Astsaturov I, Cheung R, Gunaratnam L, Kubiak V, Cortez MA, Moscarello M, O'Connor PW, McKerlie C, Becker DJ, Dosch HM. · The Hospital For Sick Children, St. Michael's Hospital, University of Toronto, Sunnybrook and Women's College Health Sciences Center, University of Toronto, Ontario, Canada. · J Immunol. · Pubmed #11160351 links to  free full text

Abstract: Type I diabetes and multiple sclerosis (MS) are distinct autoimmune diseases where T cells target either islet or CNS self-proteins. Unexpectedly, we found that autoreactive T cells in diabetic patients, relatives with high diabetes risk, nonobese diabetic (NOD) mice, and MS patients routinely target classical islet as well as CNS autoantigens. The pathogenic potential of CNS autoreactivity was testable in NOD mice. Pertussis holotoxin, without additional Ags or adjuvants, allowed development of an NOD mouse-specific, autoimmune encephalitis with variable primary-progressive, monophasic, and relapsing-remitting courses. T cells from diabetic donors transferred CNS disease to pertussis toxin-pretreated NOD.scid mice, with accumulation of CD3/IFN-gamma transcripts in the brain. Diabetes and MS appear more closely related than previously perceived. NOD mouse-specific, autoimmune encephalitis provides a new MS model to identify factors that determine alternative disease outcomes in hosts with similar autoreactive T cell repertoires.

Goodin DS, Frohman EM, Hurwitz B, O'Connor PW, Oger JJ, Reder AT, Stevens JC. · University of California, San Francisco, CA, USA. · Neurology. · Pubmed #17389300 No free full text.

Abstract: The clinical and radiologic impact of developing neutralizing antibodies (NAbs) to interferon beta (IFNbeta) while on this therapy for multiple sclerosis (MS) is assessed. On the basis of Class II and III evidence, it is concluded that treatment of patients with MS with IFNbeta (Avonex, Betaseron, or Rebif) is associated with the production of NAbs (Level A). NAbs in the serum are probably associated with a reduction in the radiographic and clinical effectiveness of IFNbeta treatment (Level B). In addition, the rate of NAb production is probably less with IFNbeta-1a treatment than with IFNbeta-1b treatment, although the magnitude and persistence of this difference is difficult to determine (Level B). Finally, it is probable that there is a difference in seroprevalence due to variability in the dose of IFNbeta injected or in the frequency or route of its administration (Level B). Regardless of the explanation, it seems clear that IFNbeta-1a (as it is currently formulated for IM injection) is less immunogenic than the current IFNbeta preparations (either IFNbeta-1a or IFNbeta-1b) given multiple times per week subcutaneously (Level A). However, because NAbs disappear in some patients even with continued IFNbeta treatment (especially in patients with low titers), the persistence of this difference is difficult to determine (Level B). Although the finding of sustained high-titer NAbs (>100 to 200 NU/mL) is associated with a reduction in the therapeutic effects of IFNbeta on radiographic and clinical measures of MS disease activity, there is insufficient information on the utilization of NAb testing to provide specific recommendations regarding when to test, which test to use, how many tests are necessary, or which cutoff titer to apply (Level U).