Stroke after initiation of interferon-beta treatment for relapsing-remitting disseminated white matter disease

Evaluating the safety of β-interferons in MS: A series of nested case-control studies

OBJECTIVE

To examine the association between interferon-β (IFN-β) and potential adverse events using population-based health administrative data in British Columbia, Canada.

METHODS

Patients with relapsing-remitting multiple sclerosis (RRMS) who were registered at a British Columbia Multiple Sclerosis Clinic (1995-2004) were eligible for inclusion and were followed up until death, absence from British Columbia, exposure to a non-IFN-β disease-modifying drug, or December 31, 2008. Incidence rates were estimated for each potential adverse event (selected a priori and defined with ICD-9/10 diagnosis codes from physician and hospital claims). A nested case-control study was conducted to assess the odds of previous IFN-β exposure for each potential adverse event with at least 30 cases. Cases were matched by age (±5 years), sex, and year of cohort entry, with up to 20 randomly selected (by incidence density sampling) controls. Odds ratios (ORs) with 95% confidence intervals (95% CIs) were estimated with conditional logistic regression adjusted for age at cohort entry.

RESULTS

Of the 2,485 eligible patients, 77.9% were women, and 1,031 were treated with IFN-β during follow-up. From the incidence analyses, 27 of the 47 potential adverse events had at least 30 cases. Patients with incident stroke (ORadj 1.83, 95% CI 1.16-2.89), migraine (ORadj 1.55, 95% CI 1.18-2.04), depression (ORadj 1.33, 95% CI 1.13-1.56), and hematologic abnormalities (ORadj 1.32, 95% CI 1.01-1.72) were more likely to have previous exposure to IFN-β than controls.

CONCLUSIONS

Among patients with RRMS, IFN-β was associated with a 1.8- and 1.6-fold increase in the risk of stroke and migraine and 1.3-fold increases in depression and hematologic abnormalities.

Adverse events of interferon beta-1a: a prospective multi-centre international ICH-GCP-based CRO-supported external validation study in daily practice

Background

Due to methodological shortcomings the available post-registration data on the adverse events (AEs) occurring in interferon beta-1a (INFb-1a)-treated patients fail to adequately validate phase III data and only partially inform on safety in daily practice. We assessed AEs in relapsing remitting multiple sclerosis (RRMS) patients treated with intramuscular (IM) INFb-1a in daily practice using data quality assurance measures similar to those in phase III trials.

Methods

A prospective, International Conference on Harmonization (ICH) - Good Clinical Practice (GCP)-based, clinical research organization (CRO)-supported study in 36 practices in the Netherlands, Belgium, the United Kingdom and Luxembourg. During 24 months after start of IM INFb-1a treatment 275 RRMS patients were assessed for AEs' severity (mild, moderate, severe) and relationship to treatment (not, unlikely, likely, definite). Data were compared with those reported in the pivotal phase III trial.

Findings

75.3% of the patients experienced one or more AEs that were likely or definitely related to INFb-1a. Of all AEs 40.5% were likely or definitely treatment-related; 68.5% of these were mild, and 3% severe. 6.6% of the patients discontinued treatment because of an AE. Compared to the pivotal phase III trial, we found statistically significantly lower incidences for most of the common AEs: headache, muscle ache, fatigue, fever, chills, nausea. One patient died following two cerebral vascular events in study month 22, both AEs were assessed as not related to INFb-1a.

Conclusion

Three out of four RRMS patients treated with IM INFb-1a in daily practice experience treatment-related AEs, most of these being mild. Our data externally validate the favorable phase III safety profile of IM INFb-1a and suggest that the real-life incidence of treatment-related AEs is less than reported in the pivotal phase III trial. Larger studies are needed to detect rare, potentially hazardous AEs of IM INFb-1a.

[A 38-year old HIV infected male with neurological focality during treatment of hepatitis]

A 38-year old HIV infected male (with adequate immunologic and virologic control) and HCV who, after starting treatment with interferon, experienced loss of strength in the left hemisphere and parenthesis in 4th and 5th fingers of the left hand along with walking instability. Imaging and microbiological tests were performed, brain biopsy finally being necessary for the diagnosis.

Possible involvement of interferon beta in post-operative vasculitis restricted to the tumour bed: a case report

Cerebral vasculitis is a very rare complication after brain tumour surgery. We herein report a case and discuss the origins of this complication. A 52-year-old female was admitted because of motor aphasia due to a left frontal lobe brain tumour. The magnetic resonance imaging (MRI) study revealed a non-enhanced tumour. A partial resection of the tumour and the placement of an Ommaya's reservoir were performed. The pathological diagnosis was an oligoastrocytoma. The patient recovered well without any neurological deficits. Post-operative radiotherapy and the intravenous injection of interferon beta were performed. During these treatments, the patient showed a continued high fever. An MRI scan revealed multiple enhanced lesions in the residual tumour, thus raising suspicions about a post-operative infection. We therefore performed a tumour biopsy and the removal of the exogenous materials. The histopathological diagnosis was vasculitis in the residual tumour. The patient's consciousness and neurological symptoms recovered quickly with the steroid treatment. Following the radiotherapy (50 Gy total), complete remission of the tumour was rapidly obtained and no recurrence was observed. Cerebral vasculitis confined to the tumour bed is an unusual complication; however, this special condition was of critical importance for a successful tumour regression in this patient.

Central nervous system vasculitis in children

Central nervous system (CNS) vasculitis is an increasingly recognized, often devastating inflammatory brain disease of children and adults. In primary or isolated CNS vasculitis/angiitis of childhood (cPACNS), the vascular inflammation is limited to the brain and spinal cord. Secondary CNS vasculitis occurs in a variety of conditions including infections, collagen vascular diseases, systemic vasculidities, and malignancies. Mimics of CNS vasculitis in children include dissections and noninflammatory vasculopathies. Diagnosis of primary CNS vasculitis in both adults and children is based on the Calabrese criteria. This review summarizes recent data on CNS vasculitis in children; reviews the clinical spectrum at presentation and the role of laboratory tests, neuroimaging, and brain biopsy; and discusses treatment strategies, outcome data, and overlapping conditions of cPACNS.