Therapeutic effect of mitoxantrone combined with methylprednisolone in multiple sclerosis: a randomised multicentre study of active disease using MRI and clinical criteria

Multiple Sclerosis: Immunotherapy

Given our current knowledge, there is a need for the early institution of immunomodulatory therapy, especially for patients with poor prognostic factors (motor and cerebellar symptoms, frequent disease exacerbations, and a high level of activity on magnetic resonance imaging ). Patients who progress despite immunomodulatory therapy should be reevaluated in terms of diagnosis, development of neutralizing antibodies, or compliance. If a patient has a partial response to immunomodulatory therapy but his or her disease, as assessed by clinical and MRI criteria, remains very active, every effort should be made to modify disease progression by searching for an immunosuppressive therapy regimen before irreversible and considerable disability has accumulated. For the majority of patients, multiple sclerosis (MS) is a chronic condition. Therefore, until a curative treatment has been developed, the available repertoire of immunosuppressive or immunomodulatory treatments should be assessed with respect to the possibility of long-term use. This is particularly important for new immunosuppressive drugs, such as cladribine or mitoxantrone, or for invasive procedures, such as total lymphoid irradiation or autologous bone marrow transplantation. For the latter treatments, experience with long-term administration is not available or the potential side effects (eg, cardiotoxicity with mitoxantrone) limit the cumulative dose. These considerations may limit long-term administration and thus the general usefulness of some drugs. Even with proven efficacy, we need to define the next step once treatment has to be discontinued. We should also address whether exacerbating disease by discontinuing an effective therapy is a potential hazard. What other therapeutic options remain once the current treatment is discontinued? Answers are not readily available at the moment, but the question should influence our decisions in the selection of traditional, well-studied or new, potentially promising therapies.

Recent developments in drug therapy for multiple sclerosis

Symptomatic treatment of multiple sclerosis (MS) includes a diverse range of drugs intended to relieve the specific symptoms with which a patient may present at a particular point in the progression of the disease. These drugs, not specifically designed for the treatment of MS, may include antispastic agents (e.g. baclofen), drugs to reduce tremor (e.g. clonazepam), anticholinergics (e.g. oxybutynin) which relieve urinary symptoms, anti-epileptics (e.g. carbamazepine) to control neuralgia, stimulants to reduce fatigue (e.g. amantadine), and antidepressants (e.g. fluoxetine) to treat depression. The treatment of acute relapses or exacerbations is dominated by corticosteroids such as methylprednisolone. The most active area of current investigation is the development of drugs which will inhibit the progression of the disease process itself, and in this category the beta- and alpha-interferons are the most effective drugs currently available, although many new treatments are currently in trials, including immunoglobulin, copolymer-1. bovine myelin, T-cell receptor (TCR) peptide vaccines, platelet activating factor (PAF) antagonists, matrix metallo-proteinase inhibitors, campath-1, and insulin-like growth factor (IGF).

Current status of multiple sclerosis therapy in Germany: a national survey

We conducted a semi-standardized enquiry concerning diagnostic, immunotherapeutic and supportive care strategies for multiple sclerosis (MS). A questionnaire was sent to all German neurological departments in December 1996, with 63% (n = 244) responding before May 1997. As might be expected, MS therapy in Germany is not very standardized. Most clinics use intravenous steroids for treating relapses, although with different dosing regimens. Nevertheless, oral steroids are also used. Interferon-beta and azathioprine are both used for the treatment of relapsing-remitting MS at the same frequency. Only 33% of German neurological departments said that they used an immunomodulating agent for chronic-progressive cases, indicating it in about 50% of cases. Azathioprine is the drug of first choice, followed by methotrexate. Regarding supportive care measures, the technique of intermittent self-catheterization is widely under-represented. Despite the lack of conclusive evidence from prospective studies for the value of azathioprine, it is still one of the most commonly used drugs for the treatment of relapsing-remitting and chronic-progressive MS. There was no evidence of a consensus on treatment standards for chronic-progressive disease courses.

Choosing drug therapy for multiple sclerosis. An update

Multiple sclerosis (MS) is an immunologically mediated disorder in which inflammation and demyelination of the central nervous system white matter are prominent features, resulting in various neurological signs and symptoms. In most patients, the course of the disease is initially characterised by relapses and remissions. In patients with chronic disease there is a tendency towards a gradually progressive disease course. MS relapses can best be treated with a course of high dose intravenous methylprednisolone. In ambulatory patients with relapsing remitting MS, partial prevention of relapses can be achieved by the use of interferon-beta-1a or -1b, whereas there is (as yet less convincing) evidence that glatiramer acetate (copolymer-1) might also be effective. At this time, there is no proof that these drugs are effective in patients with progressive MS, although trial results are expected to be available soon. In patients with rapidly progressive disease, it might be worth considering the effect of methotrexate. Future treatment options include new strategies to interfere with disease-relevant, specific or nonspecific immune mechanisms as well as drugs that might promote remyelination. In spite of the advances that have been made over the past few years, symptomatic treatment, including a multidisciplinary rehabilitation approach, remains the mainstay of treatment of the majority of MS patients.

Determinants of Gd-enhanced MRI response to IFN-beta-1a treatment in relapsing-remitting multiple sclerosis

The decision to use interferon beta (IFN-beta) as a treatment for relapsing-remitting multiple sclerosis (RRMS) is based on both clinical characteristics and course of the disease. To better identify the profile of responders, the relationships between baseline clinical/MRI characteristics and therapeutical response was analyzed in 49 patients with RRMS randomly assigned to receive subcutaneously 3 or 9 MIU of IFN-beta-1a. The therapeutical response was evaluated as a per cent change in the mean number and volume of monthly Gd-enhancing lesions in both first (early response) and second (late response) 6-month period of treatment, compared to the 6-month pre-treatment period. A better early response was seen in patients with a lower number of relapses during the pre-treatment period, while the late response was favourably influenced by a lower baseline EDSS and the high dose. Our findings suggest that the effect of IFN-beta-1 a on disease MRI activity is dose-related and dependent on the relapse rate and the level of disability before treatment.

Precision and reliability for measurement of change in MRI lesion volume in multiple sclerosis: a comparison of two computer assisted techniques

OBJECTIVE

The serial quantification of MRI lesion load in multiple sclerosis provides an effective tool for monitoring disease progression and this has led to its increasing use as an outcome measure in treatment trials. Segmentation techniques must display a high degree of precision and reliability if they are to be responsive to small changes over time. This study has evaluated the performance of two such techniques, the manual outlining and contour methods, in serial lesion load quantification.

METHODS

Sixteen patients with clinically definite multiple sclerosis were scanned at baseline and after two years. Scan analysis was performed twice, independently by three observers using each technique.

RESULTS

For the absolute lesion volumes the median intrarater coefficient of variation (CV) was 3.2% for the contour technique and 7.6% for the manual outlining method (p < 0.005), the interrater CVs were 3.8% and 6.1% respectively (p < 0.01) and the reliability of both techniques was very high. For the change in lesion volume the intrarater and interrater repeatability coefficients were respectively 2.6 cm3 and 2.8 cm3 for the contour technique, and 3.3 cm3 and 3.7 cm3 for the manual outlining method (lower values reflect higher precision). The values for intrarater and interrater reliability for measuring change in lesion volume were respectively, 0.945 and 0.944 for the contour technique, and 0.939 and 0.921 for the manual outline method (perfect reliability = 1.0).

CONCLUSIONS

With such high values for reliability, the impact of measurement error in lesion segmentation on sample size requirements in multiple sclerosis treatment trials is minor. This study shows that a change in lesion volume can be measured with a higher level of precision and reliability with the contour technique and this supports its further application in serial studies.

A 21 point unifying hypothesis on the etiology and treatment of multiple sclerosis

Multiple sclerosis (MS) is postulated to be a cell mediated autoimmune disease directed against central nervous system myelin components. Our understanding of the disease has been enhanced by a number of factors: 1) advances in our understanding of the immune system; 2) clinical trials which are beginning to identify treatments which can affect MS; 3) a better understanding of the clinical features of MS; and 4) advances in MRI imaging of the brain. Based on the current state of knowledge, this paper proposes a 21 point unifying hypothesis on the etiology and treatment of the disease. This hypothesis makes a series of assumptions, many of which are unproven, and is presented as a framework from which to investigate and treat the disease, not as a established biology. It is hypothesized that the underlying pathogenesis of MS is related to an inappropriate class of immune response against myelin antigens favoring proinflammatory Th1 versus anti-inflammatory Th2 or Th3 type responses. Environmental and genetic factors predispose toward MS by affecting the class of response and effectiveness of treatment is also related to how it impacts on this common final pathway. Because of epitope spreading, there is not one autoantigen involved in MS and the progressive form of MS differs immunologically from the relapsing remitting form. Viruses trigger and perpetuate MS, although MS is not related to a persistent viral infection. Because MS is a multifactorial disease, there are clinical and perhaps immunological subtypes of MS and a single type of treatment is unlikely to control the disease in all patients. Thus, there will be responders and non-responders to each effective therapy and ultimately combination therapy will be required to cure the disease.

Correlations between monthly enhanced MRI lesion rate and changes in T2 lesion volume in multiple sclerosis

Magnetic resonance imaging (MRI) provides a powerful tool for assessing disease activity in multiple sclerosis (MS), and its role as a surrogate marker for monitoring treatment efficacy is now becoming established. The most commonly used MRI parameters in treatment trials are (1) monthly gadolinium-enhanced MRI, with the number of active lesions serving as the outcome measure, and (2) annual lesion load quantification, in which change in MS lesion volume provides the MRI endpoint. We evaluated clinical/MRI correlations and the relationship between these two markers of disease activity in 73 patients with clinically definite MS. Quantification of T2 lesion load was performed at study entry and exit, with a median study duration of 11 months (range, 9 to 14 months). Monthly postgadolinium T1-weighted images were acquired between these time points. Lesion load at study entry was significantly correlated with the baseline Expanded Disability Status Scale (EDSS) score, but no significant longitudinal correlation was demonstrated. The number of enhancing lesions on the entry scan was predictive of subsequent relapse rate over the study duration and also correlated with the subsequent enhancing lesion activity over the study period. A significant correlation was found between change in lesion load and disease activity on the monthly scans. Our results suggest that annual lesion load quantification provides an efficient measure of ongoing disease activity, and this supports its application as a surrogate marker of disease evolution in phase III treatment trials.

Exploratory treatment trials in multiple sclerosis using MRI: sample size calculations for relapsing-remitting and secondary progressive subgroups using placebo controlled parallel groups

OBJECTIVES

Serial brain MRI is widely used in pilot studies of new agents to monitor treatment efficacy in relapsing-remitting (RR) and secondary progressive (SP) multiple sclerosis (MS). For pilot trials, sample size calculations for the RR subgroup are based on the data from small numbers of patients and separate calculations for the SP subgroup have not been performed. The present study considers these issues.

METHODS

The sample size calculations were based on data from six months of monthly T2 weighted and gadolinium enhanced MRI in 31 RR and 28 SP untreated patients undergoing natural history studies or in the placebo arm of a therapeutic trial. The calculations were for a placebo controlled, parallel groups design lasting six months. The sample sizes were based on bootstrap analysis with an 80% likelihood of showing a given treatment effect.

RESULTS

With a single pretreatment scan, demonstration of a 70% reduction in newly active lesions required 2x30 RR and 2x50 SP patients. With an extra run-in scan one month before treatment, the sample sizes were 2x20 for RR and 2x30 for SP patients.

CONCLUSIONS

The sample sizes required for RR patients were comparable with previous smaller studies. Larger sample sizes were needed for the SP group, but the extra run in scan resulted in a reduction in both groups. The larger sample sizes in the SPMS group were probably due to the combination of a higher proportion of patients with low MRI activity (< or =2 active MRI lesions in 50% of SP and 32% RR patients), as well as a few patients who displayed extremely high activity, thus increasing interpatient variability. These data should be considered in planning pilot MRI outcome trials.