RECORD STATUS: None CITATION: Volger-Sweet B. Natalizumab. University HealthSystem Consortium (UHC). Drug Monograph. 2005

Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system which is accompanied by considerable disability and high costs. This report summarises the evidence on effectiveness and costs of beta-interferons and natalizumab in the treatment of multiple sclerosis.The review included systematic reviews and randomised controlled trials (with an observation time of at least one year) in patients with MS which assessed outcome parameters such as progression, exacerbations and adverse effects. An extensive literature search included databases such as MEDLINE, EMBASE, the Cochrane Library and various HTA-databases. Studies were selected according to predefined criteria, their quality was assessed according to criteria defined prospectively, and data were summarised systematically in tables. Cost-effectiveness evaluations were also included.Two systematic reviews and 24 randomised controlled trials of beta-interferon therapy were included, as well as three trials on the effectiveness of natalizumab. A total of 22 cost-effectiveness analyses for interferons were included, whereas no economic evaluations for natalizumab were identified.Use of interferon beta-1a or interferon beta-1b after a first demyelinating event led to a reduction of the conversion to definite MS during an observation time of two to three years. In relapsing remitting MS, interferon beta-1a reduced progression. The effects of interferon beta-1b on progression are unclear. Interferon beta-1a and interferon beta-1b reduced in some but not all studies outcomes relating to exacerbations. In direct comparison trials, interferon beta-1b (Betaferon(®) or Betaseron(®)) and interferon beta-1a (Rebif(®), higher dosage of 44 µg three subcutaneous injections per week) proved superior to interferon beta-1a (Avonex(®), 30 µg per week intramuscular) with respect to exacerbation outcomes. For secondary progressive MS, only one of five studies found a reduced progression with interferon beta-1a and only a part of the studies found an improvement with respect to outcomes relating to exacerbations. For primary progressive MS no advantage of therapy with beta-interferons was found with respect to patient-related outcomes. Beta-interferons showed characteristic and frequently occurring adverse effects, including reactions at the injection site and flu-like symptoms. A large proportion of patients stop interferon therapy because of adverse events. The other main reason for stopping therapy is the felt ineffectiveness of the treatment when patients experience a new exacerbation while on treatment. Many patients produce interferon-neutralising antibodies during therapy. The ultimate effect of neutralising antibodies on the efficacy of interferon treatment is unclear.In patients with relapsing remitting (and partially with secondary progressive) MS, treatment with natalizumab led to a reduction of progression and of exacerbation rates. However, a number of cases of progressive multifocal leucoencephalopathy have been reported after natalizumab therapy. These raise serious concerns about patient safety. Reliable data on the long term effectiveness of beta-interferons or natalizumab are not yet available.The absolute cost of interferon therapy is high and the available, international cost-effectiveness analyses indicate a high cost for achieving moderate benefits in quality of life. Further research is needed to provide specific cost-effectiveness estimates for Germany.

BACKGROUND: Natalizumab (NTZ) (Tysabri®) is a monoclonal antibody that inhibits leukocyte migration across the blood-brain barrier, thus reducing inflammation in central nervous system, and has been approved worldwide for the treatment of relapsing-remitting multiple sclerosis (RRMS). OBJECTIVES: To evaluate the efficacy, tolerability and safety of NTZ in the treatment of patients with RRMS. SEARCH METHODS: We searched the Cochrane Multiple Sclerosis Group Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library, 2010, Issue 1), MEDLINE (PubMed) and EMBASE, all up to 19 February 2010, and bibliographies of papers. Handsearching was carried out. Trialists and pharmaceutical companies were contacted. Furthermore, the websites of US Food and Drug Administration (FDA), the European Medicines Evaluation Agency (EMA) and the National Institute for health and Clinical Excellence (NICE) were also checked. SELECTION CRITERIA: All double-blind, randomised, controlled trials analysing more than a single infusion of NTZ (dosage > 3 mg/kg intravenous infusion every 4 weeks), also including its use as add-on treatment, versus placebo or other drugs in patients with RRMS. No restrictions on the basis of duration of treatment or length of follow up. DATA COLLECTION AND ANALYSIS: Three reviewers independently selected articles which met the inclusion criteria. Disagreements were solved by discussion. Two reviewers independently extracted the data and assessed the methodological quality of each trial. Missing data was sought by contacting principal authors and Biogen Idec, through Biogen-Dompé Italia. MAIN RESULTS: Three studies met the inclusion criteria. These included one placebo-controlled trial (942 patients) and two add-on placebo-controlled trials, i.e. one plus glatiramer acetate (110 patients) and the second plus interferon beta-1a (1171 patients). This review assessed the efficacy, tolerability and safety of NTZ in patients with RRMS. Data was conclusive with respect to efficacy and tolerability, but not safety. As far as efficacy is concerned, the results showed statistically significant evidence in favour of NTZ for all the primary outcomes and for the secondary ones where data was available. NTZ reduced the risk of experiencing at least one new exacerbation at 2 years by about 40% and of experiencing progression at 2 years by about 25% as compared to a control group. MRI parameters showed statistical evidence in favour of participants receiving NTZ. Infusion reactions, anxiety, sinus congestion, lower limb swelling, rigors, vaginitis and menstrual disorders were reported as adverse events (AEs) more frequently after NTZ treatment. In this review NTZ was found to be well tolerated over a follow-up period of two years: the number of patients experiencing at least one AE (including severe and serious AEs) during this period did not differ between NTZ-treated patients and controls. Safety concerns have been raised about Progressive Multifocal Leukoencephalopathy (PML). In the trials included in this review, two cases of PML were encountered: one in a patient who had received 29 doses of NTZ and a second fatal case of PML in another patient after 37 doses of NTZ. Our protocol was insufficient to evaluate PML risk as well as other rare and long-term adverse events such as cancers and other opportunistic infections, which are very important issues in considering the risk/benefit ratio of NTZ. AUTHORS' CONCLUSIONS: Although one trial did not contribute to efficacy results due to its duration, we found robust evidence in favour of a reduction in relapses and disability at 2 years in RRMS patients treated with NTZ. The drug was well tolerated. There are current significant safety concerns due to reporting of an increasing number of PML cases in patients treated with NTZ. This review was unable to provide an up-to-date systematic assessment of the risk due to the maximum 2 year-duration of the trials included. An independent systematic review of the safety profile of NTZ is warranted. NTZ should be used only by skilled neurologists in MS centres under surveillance programs. All the data in this review came from trials supported by the Pharmaceutical Industry. In agreement with the Cochrane Collaboration policy, this may be considered a potential source of bias.

BACKGROUND: Natalizumab, a therapeutic monoclonal antibody approved for the treatment of relapsing-remitting multiple sclerosis (RRMS), is recommended to be withdrawn 3 months prior to a planned pregnancy. Our aim was to analyse the safety and impact of natalizumab exposure on course of disease and pregnancy outcome. OBJECTIVES: Prospective follow-up of women with MS who became accidentally pregnant during natalizumab treatment in comparison with pregnancies of women with MS not exposed to disease-modifying treatments (DMT). METHOD: 35 women with MS who became accidentally pregnant while treated with natalizumab, and 23 women with MS who became pregnant devoid of any DMT as a control group, were chosen. RESULTS: All pregnancies except one were followed in a prospective fashion. Of the women exposed to natalizumab during pregnancy, 29 women gave birth to 28 healthy children; one child was born with hexadactyly. Five pregnancies ended in an early miscarriage and one woman decided to undergo an elective termination of pregnancy. MS activity did not rebound during pregnancy or post partum after natalizumab was withdrawn, and no significant differences were observed when compared with the non-DMT-exposed control group. CONCLUSION: Our data may support the notion that an elective termination of pregnancy due to natalizumab exposure may not be necessary, but rather requires careful monitoring. Women should still be advised to stop natalizumab in the course of planned pregnancy until more data on long-term outcomes are available.

RECORD STATUS: None CITATION: Natalizumab for multiple sclerosis.. NIHR Health Technology Assessment programme.

BACKGROUND: In chronic inflammatory conditions such as Crohn's disease, the migration of leukocytes from the circulation into the parenchyma and their activation within inflammatory sites are mediated in part by alpha4 integrins. METHODS: We conducted a double-blind, placebo-controlled trial of the alpha4 integrin-specific humanized monoclonal antibody natalizumab in 248 patients with moderate-to-severe Crohn's disease. Patients were randomly assigned to receive one of four treatments: two infusions of placebo; one infusion of 3 mg of natalizumab per kilogram of body weight, followed by placebo; two infusions of 3 mg of natalizumab per kilogram; or two infusions of 6 mg of natalizumab per kilogram. Infusions were given four weeks apart. Outcomes included changes in scores for the Crohn's Disease Activity Index (higher scores indicate more severe disease), the health-related quality of life, and C-reactive protein levels. RESULTS: The group given two infusions of 6 mg of natalizumab per kilogram did not have a significantly higher rate of clinical remission (defined by a score of less than 150 on the Crohn's Disease Activity Index) than the placebo group at week 6 (the prospectively defined primary end point in the efficacy analysis). However, both groups that received two infusions of natalizumab had higher remission rates than the placebo group at multiple time points. Natalizumab also produced a significant improvement in response rates (defined by a reduction of at least 70 points in the score on the Crohn's Disease Activity Index). The highest remission rate was 44 percent and the highest response rate was 71 percent (at week 6 in the group given two infusions of 3 mg per kilogram). Overall, the two infusions of 6 mg of natalizumab per kilogram and of 3 mg per kilogram had similar effects. The quality of life improved in all natalizumab groups; C-reactive protein levels improved in groups receiving two infusions of natalizumab. The rates of adverse events were similar in all four groups. CONCLUSIONS: Treatment with the selective adhesion-molecule inhibitor natalizumab increased the rates of clinical remission and response, improved the quality of life and C-reactive protein levels, and was well tolerated in patients with active Crohn's disease.

OBJECTIVE: To perform pharmacoeconomic assessment of interferone-1a for intramuscular and subcortical infusions, interferon-beta-1b, glatiramer acetate and natalizumab in the treatment of relapsing-remitting multiple sclerosis (RRMS). MATERIAL AND METHODS: Modeling and "cost-effectiveness" analysis as well as evaluation of "disease cost" were performed. A model was based on the data on the efficacy of the drugs, summarized in the meta-analysis of G.Filippini et al, and treatment costs in the Russian health care system. To compare the efficacy, we used a criteria of "reduction of the risk of 1 and more relapses during 2 years of treatment compared to placebo". The analysis of treatment costs of patients with RRMS included direct treatment costs during the remission, medical care costs and costs of disease-modifying drugs (DMD). The analysis of direct costs was performed using standards of treatment of patients with multiple sclerosis. The duration of the study was 2 years. RESULTS AND CONCLUSION: Based on the meta analysis, we calculated the relative decrease of the risk of 1 and more relapses during 2 years of treatment as 3,6 % for interferon-beta-1b for intramuscular infusions (avonex), 15,2% for interferon-beta-1b for subcortical infusions (rebif), 10,5% for interferon-beta-1b for (betaferon), 21,6% for glatiramer acetate (copaxone), 42,8% for natalizumab (tisabri). For 2 years, total management costs per patient were 1567082,98 rub for avonex, 1563369,38 rub for rebif, 1322 635,80 for betaferon, 1 459 976,15 rub. for copaxone and 2 694 699,35 rub. for tisabri. The minimal cost/effectiveness ratio (62 960,27 rub.) was calculated for natalizumab. This drug was most preferable in terms of economic effectiveness.

Natalizumab is a humanized monoclonal antibody with a selective adhesion-molecule inhibitor effect, and a demonstrated efficacy in decreasing the frequency of relapses and progression of disability in relapsing-remitting multiple sclerosis (RR MS). After the approval of FDA and EMEA in MS cases unresponsive to immunomodulating therapy or in severe MS patients also not previously treated with interferons, and considering the concern on the possible side effects, an accurate program of surveillance was organized in our country by a combined effort of AIFA, Cineca, Department of Pharmacology of University of Bologna, and a group of neurologists appointed by the National Society of Neurology (SIN). After 15 months from the authorization of natalizumab therapy in MS, as of 31 March 2008, 908 cases have been treated with natalizumab and enrolled in this pharmaco-vigilance study. The mean age is 35 years, while the duration of disease is longer and disability is higher than that reported in the registrative study. Side effects are at the moment mild and similar to those previously described. At follow-up, the majority of treated cases are stable or ameliorated. The treatment was discontinued in 6% of patients.

The use of natalizumab has likely been limited by its association with progressive multifocal leukoencephalopathy (PML), an infection caused by the human polyomavirus John Cunningham (JC). Three factors were recently identified that contribute to the overall risk of natalizumab-associated PML: (1) Positive serostatus for anti-JCV antibodies, (2) prior use of immunosuppressants, and (3) duration of natalizumab therapy. This risk stratification algorithm has not led to a reduction in the incidence of PML in natalizumab-treated patients with multiple sclerosis between April 2010 and February 2014. This observation may appear perplexing, as treatment duration and JCV serostatus are modifiable risk factors. Potential reasons for the lack of success of companion diagnostics that determine the overall risk of natalizumab-associated PML are discussed.

RECORD STATUS: None CITATION: Clar C, Velasco-Garrido M, Gericke C. Interferone und natalizumab in der behandlung der multiplen sklerose (MS). [Interferons and natalizumab for multiple sclerosis] Cologne: German Agency for Health Technology Assessment at the German Institute for Medical Documentation and Information (DAHTA@ DIMDI). DAHTA077. 2008