Subcutaneous Recombinant Interferon-??-1a (Rebif??)

Magnetic resonance imaging reveals therapeutic effects of interferon-beta on cytokine-induced reactivation of rat model of multiple sclerosis

Interferon-β (IFN-β) drugs are considered to derive their beneficial effects on multiple sclerosis (MS) progression via their antiinflammatory properties, but the precise mechanism of action remains unclear. Here, we sought to discover how IFN-β impacts on inflammation-associated aggravation of MS-like lesions in rat. Animals with dormant focal experimental allergic encephalomyelitis (EAE) lesions were challenged intravenously with a replication-deficient adenovirus vector carrying interleukin (IL)-1β cDNA (AdIL-1β). Aggravation of inflammation and demyelination within the focal EAE lesion was observed after AdIL-1β injection with associated changes in tissue structure detected by diffusion and magnetization transfer imaging. Postgadolinium-DTPA T1-weighted images revealed contrast enhancement in the ipsilateral meninges, indicating breakdown of the blood-cerebrospinal fluid barrier, and increased left/right regional cerebral blood volume ratio was also observed after AdIL-1β injection. To determine the role of IFN-β on reactivation of the EAE lesion, rats were treated with therapeutic doses of IFN-β and focal EAE lesions showed significantly reduced reactivation in response to systemic AdIL-1β injection. In conclusion, these findings indicate a central role for peripheral IL-1β expression in the mechanism of MS lesion reactivation and that the therapeutic effects of IFN-β may, at least in part, reflect suppression of the effects of peripheral inflammation on MS lesion pathogenesis.

Cost-effectiveness of multiple sclerosis disease-modifying therapies: a systematic review of the literature

Objective. To provide a current and comprehensive understanding of the cost-effectiveness of DMTs for the treatment of MS by quantitatively evaluating the quality of recent cost-effectiveness studies and exploring how the field has progressed from past recommendations. Methods. We assessed the quality of studies that met our systematic literature search criteria using the Quality of Health Economic Studies validated instrument. Results. Of the 82 studies that met our initial search criteria, we included 22 in this review. Four studies (18%) achieved quality category 2, three studies (14%) achieved quality category 3, and 15 studies (68%) achieved the highest quality category 4. 91% of studies were simulation models. 13 studies (59%) had quality-adjusted life years (QALYs) as the primary outcome measure, included a societal perspective in the analysis, and utilized time horizons of 10 years to lifetime. Conclusions. To continue to improve the cost-effectiveness evidence of DMTs, we recommend: lifetime horizons, societal perspectives, and QALYs; supplemental evidence with shorter horizons, payer perspectives, and clinical outcomes to inform multiple decision makers; development of modeling and input standards for comparability; head-to-head RCTs between DMTs and long-term prospective studies; and comprehensive cost-effectiveness studies that compare all appropriate DMTs.

Subcutaneous recombinant interferon-β-1a (Rebif®): a review of its use in the treatment of relapsing multiple sclerosis

Subcutaneous recombinant interferon-β-1a (SC IFNβ-1a) [Rebif®] is indicated as monotherapy for the prevention of relapses and progression of physical disability in patients with relapsing multiple sclerosis (MS). This article reviews the efficacy and tolerability of SC IFNβ-1a in this indication, with further discussion of its pharmacological properties and pertinent pharmacoeconomic studies. SC IFNβ-1a efficacy and tolerability were evaluated in randomized, double-blind, multinational trials in patients with relapsing-remitting MS (RRMS). Its efficacy was demonstrated in the 2-year PRISMS trial, as SC IFNβ-1a 22 or 44 μg three times weekly (tiw) significantly reduced relapse rates, with an ≈30% relative risk reduction compared with placebo. SC IFNβ-1a was also associated with significantly delayed progression of disability, and lower disease activity according to MRI, relative to placebo. In the 24-week EVIDENCE trial, a significantly higher proportion of SC IFNβ-1a 44 μg tiw than intramuscular IFNβ-1a (Avonex®) 30 μg once weekly recipients remained relapse free. A serum-free formulation of SC IFNβ-1a 44 μg tiw was more efficacious than placebo in preventing the development of brain lesions in the 16-week IMPROVE trial. In the 96-week REGARD trial, the efficacy of SC IFNβ-1a 44 μg tiw was not significantly different to that of glatiramer acetate for clinical endpoints, although it was associated with reduced development of brain lesions compared with glatiramer acetate, according to some MRI endpoints. In the 36-month CAMMS223 trial, alemtuzumab led to significantly lower relapse rates and risk of developing sustained disability than SC IFNβ-1a 44 μg tiw, and was generally more efficacious according to other clinical and MRI endpoints. Across trials, influenza-like symptoms, injection-site reactions, haematological disturbances and hepatic enzyme abnormalities were the most common treatment-emergent adverse events occurring with SC IFNβ-1a. In the PRISMS trial, SC IFNβ-1a 22 and 44 μg tiw recipients had more injection-site reactions than placebo recipients and, at the higher dosage, haematological disturbances and increases in ALT levels were also significantly more frequent than with placebo. Pooled data from clinical trials and postmarketing surveillance indicate that haematological and hepatic adverse events are generally asymptomatic and rarely result in treatment discontinuation. Nevertheless, some cases of serious hepatic complications have been reported. In cost-utility studies, first-line therapies for RRMS, including SC IFNβ-1a, all exceeded commonly accepted US thresholds for incremental cost per quality-adjusted life-years gained relative to symptomatic treatment. However, because of patient need and the difficulty in adequately assessing cost utility in a gradually progressive disease, these agents have been made available to many patients worldwide through special access programmes. Overall, SC IFNβ-1a has a favourable risk-benefit ratio and is a valuable first-line treatment option for patients with relapsing MS.

Production of therapeutic proteins in algae, analysis of expression of seven human proteins in the chloroplast of Chlamydomonas reinhardtii

Recombinant proteins are widely used today in many industries, including the biopharmaceutical industry, and can be expressed in bacteria, yeasts, mammalian and insect cell cultures, or in transgenic plants and animals. In addition, transgenic algae have also been shown to support recombinant protein expression, both from the nuclear and chloroplast genomes. However, to date, there are only a few reports on recombinant proteins expressed in the algal chloroplast. It is unclear whether this is because of few attempts or of limitations of the system that preclude expression of many proteins. Thus, we sought to assess the versatility of transgenic algae as a recombinant protein production platform. To do this, we tested whether the algal chloroplast could support the expression of a diverse set of current or potential human therapeutic proteins. Of the seven proteins chosen, >50% expressed at levels sufficient for commercial production. Three expressed at 2%-3% of total soluble protein, while a forth protein accumulated to similar levels when translationally fused to a well-expressed serum amyloid protein. All of the algal chloroplast-expressed proteins are soluble and showed biological activity comparable to that of the same proteins expressed using traditional production platforms. Thus, the success rate, expression levels, and bioactivity achieved demonstrate the utility of Chlamydomonas reinhardtii as a robust platform for human therapeutic protein production.

Neutralizing and binding antibodies to interferon beta in patients with multiple sclerosis: a comparison of assay results from three italian centres

Interferon (IFN) beta therapy for multiple sclerosis (MS) is associated with the development of binding antibodies (BAbs) and neutralizing antibodies (NAbs) in a percentage of patients. This study investigated the reproducibility of results of two different antibody detection techniques using serum from 100 patients with MS who were receiving IFN beta therapy. Fifty samples were analysed using a commercially available kit-based BAb assay and a further 50 different samples were analysed using a widely used NAb cytopathic effect assay, at three different laboratories. All three centres agreed on the BAb status of all serum samples. However, only 84% agreement was reached on serum NAb status, and there was significant inter-laboratory variation in NAb titre values. Further analysis of these data revealed a correlation between the mean NAb titre and the coefficient of variation of serum samples, indicating greater discordance with higher NAb titres. A significant interlaboratory variation in NAb titres does exist; thus, caution is required when comparing titres from different centres. It is clear that validated detection assays are needed to accurately quantify NAb titres.

Safety and tolerability in relapsing-remitting multiple sclerosis patients treated with high-dose subcutaneous interferon-beta by Rebiject autoinjection over a 1-year period: the CoSa study

OBJECTIVES

Approved multiple sclerosis (MS) treatments include subcutaneous and intramuscular interferon beta (IFN-beta) Patient satisfaction during long-term IFN-beta treatment is crucial. This study investigated the satisfaction of patients with relapsing-remitting MS treated with IFN-beta-1a (Rebif) by the autoinjection system, Rebiject.

MATERIALS AND METHODS

This prospective observational study recruited subjects with relapsing-remitting MS (n = 76) from 19 neurological centers in Italy who were eligible for subcutaneous IFN-beta-1a treatment either as a first immunomodulatory therapy or as a switch from other treatments. Patients received IFN-beta-1a 44 mug 3 times weekly via the Rebiject system. A questionnaire on the use of Rebiject and the most common adverse effects related to IFN-beta-1a administration was completed monthly under the supervision of trained nurses.

RESULTS

Satisfaction with treatment was reported by 80.2% of patients who received at least 1 dose. Advantages reported for the Rebiject system included its convenience (53% of all patients), ease of use (25%), reduced trauma and pain (11% and 6%, respectively), and reduced local skin reactions (5%). No significant changes from baseline were observed regarding the frequency or severity of local reactions.

CONCLUSIONS

During the 1-year observation of this small cohort, most patients considered the Rebiject system to be convenient, with a third of the patients feeling that the system was easier to use than conventional procedures. Rebiject was also associated with less pain and trauma in some patients. Use of Rebiject may facilitate IFN-beta-1a administration and may lead to an increase in compliance and adherence, thus increasing the effectiveness of treatment.

Review of the clinical evidence for interferon beta 1a (Rebif) in the treatment of multiple sclerosis

Interferon (INF) beta 1a 22 or 44 mug (Rebif((R))) administered s.c. 3 times a week (t.i.w) is a well established immunomodulating treatment for relapsing remitting multiple sclerosis (RRMS). This review focuses on its mechanisms of action, evidence of efficacy, safety, and tolerability. Several pharmacodynamic properties explain the immunomodulatory actions of INF beta 1a 22 or 44 mug s.c. t.i.w. Pivotal trials and post-marketing studies proved that the drug is effective in reducing disease activity and likely in slowing disease progression. Head-to-head comparative studies with other marketed INFs beta in RRMS suggested a better therapeutic response associated with higher doses and frequency of administration of Rebif((R)). Additional evidence indicated a beneficial effect of INF beta 1a in patients with clinically isolated syndromes (CIS) suggestive of MS, as treatment reduced time to conversion to clinically definite (CD) disease. Further, although the drug did not prove to slow time to progression there were benefits on relapse- and MRI-related secondary outcome measures in secondary progressive (SP) MS. Pivotal trials, their cross-over extensions, and post-marketing studies consistently showed that INF beta 1a 22 or 44 mug s.c. t.i.w. is safe and well tolerated, as adverse drug reactions are usually mild and manageable.

Subcutaneous interferon-beta-1a : new formulation

The new formulation of subcutaneous interferon-beta-1a was developed without serum-derived components with the aim of improving immunogenicity and injection tolerability in patients with relapsing forms of multiple sclerosis (MS). In a prospectively defined interim analysis at 48 weeks of an ongoing, single-arm, phase IIIb trial, 13.9% of MS patients receiving the new formulation of subcutaneous interferon-beta-1a 44 microg three times weekly had developed neutralising antibodies (NAbs). In the EVIDENCE trial, which served as an historical control, 24.4% of patients receiving the same dosage of the current formulation had developed NAbs at 48 weeks. The new formulation demonstrated similar pharmacokinetic activity to that of the current formulation in a phase I, double-blind, placebo-controlled study in healthy volunteers. About two-thirds of patients with MS who received the new formulation of subcutaneous interferon-beta-1a were relapse free in the interim, 48-week analysis of the single-arm trial; this is similar to results for the current formulation from historical data. A comparison of results from the interim, 48-week analysis with historical-control data from the EVIDENCE trial indicates that the new formulation of interferon-beta-1a may be associated with a lower incidence of injection-site reactions and a higher incidence of influenza-like symptoms than the current formulation. Adverse events associated with the new formulation were mostly mild to moderate in severity

The safety and efficacy of IFN-beta products for the treatment of multiple sclerosis

Multiple sclerosis, a chronic demyelinating disease of the CNS, is now a treatable disease. Phase III clinical trials of three recombinant IFN-beta products conducted in relapsing-remitting multiple sclerosis have shown, albeit modest, significant effects on relapses and short-term progression of disability, and a more substantial effect on MRI parameters. However, these effects do not correlate well with clinical disease activity or long-term disability. Overall, IFN-beta is safe and generally well tolerated, and reported adverse events were comparable between preparations. Systemic side effects can be effectively managed by dose escalation, use of an auto-injector and careful clinical monitoring.

Remediable shortcomings in applying clinical pharmacology to neurological practice

The application of the clinical pharmacological approach to prescribing antiepileptic drugs has enhanced the efficiency of the drug treatment of epilepsy considerably. However, it would be possible to take the approach further in relation to this disorder by applying it to the more recently introduced antiepileptic drugs, to specific epileptic seizure syndromes and to seizure disorders of different degrees of activity. Similarly, the approach could be applied to the drug treatment of migraine attacks, to migraine prophylactic therapy and to the treatments of multiple sclerosis and Parkinsonism, with reasonable expectations that it would enhance the therapy of these disorders.