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Summary Background The Thymectomy Trial in Non-Thymomatous Myasthenia Gravis Patients Receiving Prednisone (MGTX) showed that thymectomy combined with prednisone was superior to prednisone alone in improving clinical status as measured by the Quantitative Myasthenia Gravis (QMG) score in patients with generalised non-thymomatous myasthenia gravis at 3 years. We investigated the long-term effects of thymectomy up to 5 years on clinical status, medication requirements, and adverse events. Methods We did a rater-blinded 2-year extension study at 36 centres in 15 countries for all patients who completed the randomised controlled MGTX and were willing to participate. MGTX patients were aged 18 to 65 years at enrolment, had generalised non-thymomatous myasthenia gravis of less than 5 years' duration, had acetylcholine receptor antibody titres of 1·00 nmol/L or higher (or concentrations of 0·50–0·99 nmol/L if diagnosis was confirmed by positive edrophonium or abnormal repetitive nerve stimulation, or abnormal single fibre electromyography), had Myasthenia Gravis Foundation of America Clinical Classification Class II–IV disease, and were on optimal anticholinesterase therapy with or without oral corticosteroids. In MGTX, patients were randomly assigned (1:1) to either thymectomy plus prednisone or prednisone alone. All patients in both groups received oral prednisone at doses titrated up to 100 mg on alternate days until they achieved minimal manifestation status. The primary endpoints of the extension phase were the time-weighted means of the QMG score and alternate-day prednisone dose from month 0 to month 60. Analyses were by intention to treat. The trial is registered with ClinicalTrials.gov, number NCT00294658. It is closed to new participants, with follow-up completed. Findings Of the 111 patients who completed the 3-year MGTX, 68 (61%) entered the extension study between Sept 1, 2009, and Aug 26, 2015 (33 in the prednisone alone group and 35 in the prednisone plus thymectomy group). 50 (74%) patients completed the 60-month assessment, 24 in the prednisone alone group and 26 in the prednisone plus thymectomy group. At 5 years, patients in the thymectomy plus prednisone group had significantly lower time-weighted mean QMG scores (5·47 [SD 3·87] vs 9·34 [5·08]; p=0·0007) and mean alternate-day prednisone doses (24 mg [SD 21] vs 48 mg [29]; p=0·0002) than did those in the prednisone alone group. 14 (42%) of 33 patients in the prednisone group, and 12 (34%) of 35 in the thymectomy plus prednisone group, had at least one adverse event by month 60. No treatment-related deaths were reported during the extension phase. Interpretation At 5 years, thymectomy plus prednisone continues to confer benefits in patients with generalised non-thymomatous myasthenia gravis compared with prednisone alone. Although caution is appropriate when generalising our findings because of the small sample size of our study, they nevertheless provide further support for the benefits of thymectomy in patients with generalised non-thymomatous myasthenia gravis. Funding National Institutes of Health, National Institute of Neurological Disorders and Stroke.

Objective T-helper 1 (Th1) and Th17 lymphocytes are involved in experimental autoimmune encephalomyelitis, the model of multiple sclerosis (MS). We characterized the Th1/Th17 cell populations in peripheral blood (PB), their interferon (IFN) receptor expression sensitivity to IFN-β in MS patients. Methods In 30 untreated patients with active MS (AMS) and 32 with inactive MS (IMS), and in 22 healthy subjects, we measured intracellular cytokine expression, interleukin-17–producing myelin basic protein–stimulated PB lymphocytes, surface IFN type I receptor chain1 (IFN-αR1) expression, IFN-β-dependent signal transducer and activator of transcription 1 (STAT1) phosphorylation, and apoptosis of anti-CD3 monoclonal antibody–stimulated PB lymphocytes. Results Th17 cell percentage increased around sevenfold in AMS compared with IMS or healthy subjects, but there was no change in Th1 cells. Th17 cells in AMS were myelin basic protein specific. The longitudinal follow-up of 18 MS patients shifting between AMS and IMS showed that the percentage of Th17 but not Th1 cells always increased in AMS. IFN-αR1 expression, IFN-β–induced STAT1 activation, and apoptosis were significantly greater in Th17 than Th1 cells. IFN-αR1 expression and IFN-β–dependent STAT1 activation progressively increased in vitro with a highly significant positive correlation only in developing Th17 but not in Th0 or Th1 cells. Interpretation Evidence that an expansion of peripheral Th17 cells, a Th subset that can infiltrate brain parenchyma and damage cells, is associated with disease activity in MS. The greater IFN-αR1 level expressed by Th17 compared with Th1 cells might make them a selective target for IFN-β therapy. Ann Neurol 2009;65:499–509

Today many different drugs are available for treatment of multiple sclerosis (MS). Interferons, glatiramer acetate, mitoxantrone, and natalizumab have been approved by the regulatory authorities of many countries for the treatment of MS. Evidence based medicine (EBM) principles allow physicians to better address the correct treatment for patients. This article aimed to review all the clinical trials on immune-modulating and immunosuppressive drugs on the basis of the EBM principles. Based on the evidence to date interferon beta represents the best therapeutic option, particularly if given at high doses and with multiple injections per week. Due to its lower efficacy, glatiramer acetate should be used as a second choice in case of intolerable side effects or toxicity of interferon beta. Great efficacy has been demonstrated for mitoxantrone and natalizumab. These drugs should be, however, used with particular attention for their potential toxic effects.

Adherence to long-term therapy has always been a problem in all fields of medicine. In multiple sclerosis (MS), treatment consists of parenteral administration of immune-modulating drugs once or several times weekly for an as yet undetermined length of time. Different studies on the MS patients' compliance showed that the most frequent cause of stopping treatment is the perceived lack of efficacy and that most treatment withdrawals occur during the first year of treatment. A trial aimed to identify the minimum effective IFNβ dose showed that some patients had disease activity after switching to a lower IFNβ dose. OPTIMS (OPTimization of Interferon dose for MS study) was a multicenter study, involving 24 Italian MS centers, 216 patients, aimed to identify a treatment response indicator allowing the early identification of poorly responding patients. A single active scan during the first 6 months of IFN treatment had a significant positive predictability of 59% (95% confidence interval, 41–76; p = 0.05) on the presence of clinical signs of disease activity during the further 2-year follow-up.

IFN-β inhibits the expansion of Th17 cells in active multiple sclerosis (AMS), and this might contribute to improve the clinical symptoms. The effectiveness of this inhibition, however, requires intact IFN-γ signaling in T cells. In this study, we report that both mRNA and cell surface expression of the signaling chain of the IFN-γ receptor (IFN-γR2) and its cognate tyrosine kinase JAK2 are enhanced in peripheral blood Th17 cells and clones from patients with AMS compared with those with inactive multiple sclerosis (IMS) or healthy subjects (HS). IFN-γ decreased the frequency of Th17 peripheral cells and proliferation of Th17 clones from AMS patients. Stimulation of PBMCs from HS in Th17-polarizing conditions resulted in the enhancement of JAK2 expression and accumulation of cell surface IFN-γR2. The role of JAK2 in the modulation of IFN-γR2 was demonstrated as its transduction prevented rapid internalization and degradation of IFN-γR2 in JAK2-deficient γ2A cells. In conclusion, these data identify JAK2 as a critical factor that stabilizes IFN-γR2 surface expression in Th17 cells from AMS patients, making them sensitive to IFN-γ. These data may have clinical implications for a better use of IFNs in multiple sclerosis and possibly other inflammatory diseases.

Today many different drugs are available for treatment of multiple sclerosis (MS). Interferons, glatiramer acetate, mitoxantrone, and natalizumab have been approved by the regulatory authorities of many countries for the treatment of MS. Evidence based medicine (EBM) principles allow physicians to better address the correct treatment for patients. This article aimed to review all the clinical trials on immune-modulating and immunosuppressive drugs on the basis of the EBM principles. Based on the evidence to date interferon beta represents the best therapeutic option, particularly if given at high doses and with multiple injections per week. Due to its lower efficacy, glatiramer acetate should be used as a second choice in case of intolerable side effects or toxicity of interferon beta. Great efficacy has been demonstrated for mitoxantrone and natalizumab. These drugs should be, however, used with particular attention for their potential toxic effects.