Study 1: Le Page et al. Mitoxantrone as induction treatment in aggressive relapsing remitting multiple sclerosis: treatment response factors in a 5 year follow-up observational study of 100 consecutive patients. J Neurol Neurosurg Psychiatry. 2008 Jan;79(1):52-6.
BACKGROUND: Mitoxantrone was approved by the French health authority (AFSAPPS) in October 2003 to treat patients with aggressive multiple sclerosis (MS).
OBJECTIVE: To report the long term effectiveness and safety of mitoxantrone as induction therapy in patients with aggressive relapsing-remitting MS, and to assess treatment response factors.
MATERIAL AND METHODS: 100 consecutive patients with aggressive relapsing-remitting MS received mitoxantrone 20 mg monthly combined with methylprednisolone 1 g for 6 months. Relapses, Expanded Disability Status Scale (EDSS) and drug safety were assessed every 6 months for up to at least 5 years. Within 6 months after induction, 73 patients received maintenance therapy (mitoxantrone every 3 months (n = 21); interferon beta (n = 25); azathioprine (n = 15); methotrexate (n = 7); glatiramer acetate (n = 5)).
RESULTS: During the 12 months following initiation of mitoxantrone, the annual relapse rate (ARR) was reduced by 91%, 78% of patients remained relapse free, MRI activity was reduced by 89%, the mean EDSS decreased by 1.2 points (p<10(-6)) and 64% of patients improved by 1 point or more on the EDSS. In the longer term, the ARR reduction was sustained (0.29-0.42 for up to 5 years), the median time to the first relapse was 2.8 years and disability remained improved after 5 years. Younger age and lower EDSS score at the start of mitoxantrone treatment were predictive of better treatment response. Three patients presented with an asymptomatic decrease in left ventricular ejection fraction to less than 50% (one reversible). One patient was diagnosed with acute myeloid leukaemia (remission 5 years after diagnosis).
CONCLUSION: Mitoxantrone monthly for 6 months as induction therapy followed by maintenance treatment showed sustained clinical benefit for up to 5 years with an acceptable adverse events profile in patients with aggressive relapsing-remitting MS.
Study 2: Edan et al. Mitoxantrone prior to interferon beta-1b in aggressive relapsing multiple sclerosis: a 3-year randomised trial. J Neurol Neurosurg Psychiatry. 2011 Dec;82(12):1344-50.
OBJECTIVES: The long-term impact of interferon-beta-1b (IFN) might be improved by short-term immunosuppression with mitoxantrone(MITOX) in aggressive relapsing-remitting multiple sclerosis (ARMS) patients.
METHODS: In this 3-year clinical and MRI study, 109 ARMS patients (two or more relapses in the previous 12 months and one or more gadolinium (Gd)-enhancing MRI lesion) were randomised into two groups: 54 patients received MITOX monthly (12 mg/m(2); maximum 20 mg) combined with 1 g of methylprednisolone (MP) for 6 months followed by IFN for the last 27 months, and 55 patients received IFN for 3 years combined with 1 g of MP monthly for the first 6 months. The primary endpoint was the time to worsen by at least one Expanded Disability Status Scale point confirmed at 3 months.
RESULTS: The time to worsen by at least one Expanded Disability Status Scale point confirmed at 3 months was delayed by 18 months in the MITOX group compared with the IFN group (p<0.012). The 3-year risk of worsening disability was reduced by 65% in the MITOX group relative to the IFN group (11.8% vs 33.6%). MITOX patients had a reduced relapse rate by 61.7%, a reduced number of Gd-enhancing lesions at month 9 and a slower accumulation of new T2 lesions at each time point.
CONCLUSIONS: Although there were limitations in this investigator-academic-driven study, the data do suggest that mitoxantrone induction therapy prior to INF beta-1b may have a role in aggressive disease.
Study 3: Hartung et al. Mitoxantrone in progressive multiple sclerosis: a placebo-controlled, double-blind, randomised, multicentre trial. Lancet. 2002 Dec 21-28;360(9350):2018-25.
BACKGROUND: Treatment options for patients with secondary progressive multiple sclerosis are few. Encouraging results in open-label studies prompted this randomised trial of mitoxantrone in such patients.
METHODS: 194 patients with worsening relapsing-remitting or secondary progressive multiple sclerosis were assigned placebo or mitoxantrone(5 mg/m(2) [exploratory group] or 12 mg/m(2) intravenously) every 3 months for 24 months. Clinical assessments were made every 3 months for 24 months. The primary endpoint was a multivariate analysis of five clinical measures. Analyses of mitoxantrone 12 mg/m(2) versus placebo were based on patients who received at least one dose and returned for at least one assessment of efficacy.
FINDINGS: Of 194 patients enrolled, 188 were able to be assessed at 24 months. There were no drug-related serious adverse events or evidence of clinically significant cardiac dysfunction. At 24 months, the mitoxantrone group experienced benefits compared with the placebo group for the primary outcome (difference 0.30 [95% CI 0.17-0.44]; p<0.0001) and the preplanned univariate analyses of those measures: change in expanded disability status scale (0.24 [0.04-0.44]; p=0.0194), change in ambulation index (0.21 [0.02-0.40]; p=0.0306), adjusted total number of treated relapses (0.38 [0.18-0.59]; p=0.0002), time to first treated relapse (0.44 [0.20-0.69]; p=0.0004), and change in standardised neurological status (0.23 [0.03-0.43]; p=0.0268).
INTERPRETATION: Mitoxantrone 12 mg/m(2) was generally well tolerated and reduced progression of disability and clinical exacerbations. Further studies are needed to identify the patients with these forms of multiple sclerosis who are most likely to respond to therapy, the best treatment protocols, and the frequency of long-term drug-related side-effects.