Subcutaneous interferon-beta-1a : new formulation

Twenty Years of Subcutaneous Interferon-Beta-1a for Multiple Sclerosis: Contemporary Perspectives

Multiple sclerosis (MS) is a chronic, progressive, inflammatory disorder of the central nervous system. Relapsing-remitting MS (RRMS), the most common form of the disease, is characterized by transient neurological dysfunction with concurrent accumulation of disability. Over the past three decades, disease-modifying therapies (DMTs) capable of reducing the frequency of relapses and slowing disability worsening have been studied and approved for use in patients with RRMS. The first DMTs were interferon-betas (IFN-βs), which were approved in the 1990s. Among them was IFN-β-1a for subcutaneous (sc) injection (Rebif®), which was approved for the treatment of MS in Europe and Canada in 1998 and in the USA in 2002. Twenty years of clinical data and experience have supported the efficacy and safety of IFN-β-1a sc in the treatment of RRMS, including pivotal trials, real-world data, and extension studies lasting up to 15 years past initial treatment. Today, IFN-β-1a sc remains an important therapeutic option in clinical use, especially around pregnancy planning and lactation, and may also be considered for aging patients, in which MS activity declines and long-term immunosuppression associated with some alternative therapies is a concern. In addition, IFN-β-1a sc is used as a comparator in many clinical studies and provides a framework for research into the mechanisms by which MS begins and progresses.

Poloxamer 188 as surfactant in biological formulations - An alternative for polysorbate 20/80?

Surfactants are used to stabilize biologics. Particularly, polysorbates (Tween® 20 and Tween® 80) dominate the group of surfactants in protein and especially antibody drug products. Since decades drug developers rely on the ethoxylated sorbitan fatty acid ester mixtures to stabilize sensitive molecules such as proteins. Reasons are (i) excellent stabilizing properties, and (ii) well recognized safety and tolerability profile of these polysorbates in humans, especially for parenteral applications. However, over the past decade concerns regarding the stability of these two polysorbates were raised. The search of alternatives with preferably less reservations concerning degradation and product quality reducing issues leads, among others, to poloxamer 188 (e.g. Kolliphor® P188), a nonionic triblock-copolymer surfactant. This review sums up our current knowledge related to the characterization and physico-chemical properties of poloxamer 188, its analytics and stability properties for biological formulations. Furthermore, the advantages and disadvantages as a suitable polysorbate-alternative for the stabilization of biologics are discussed.

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.

Review of subcutaneous interferon β-1a, delivered via the electronic self-injection device RebiSmart™, for the treatment of multiple sclerosis

Multiple sclerosis is a chronic disease requiring lifelong treatment with disease-modifying drugs that aim to prevent relapses and slow the progression of disability. The established first-line treatments for multiple sclerosis all require regular injections, and real-world observations suggest that long-term adherence to treatment is low. Indeed, poor adherence to disease-modifying drug treatment has been associated with poorer clinical outcomes. Autoinjectors have been developed to improve the success of self-injection, whilst also making injections more comfortable for patients, with the aim of minimizing obstacles to treatment adherence. RebiSmart™ is a new electronic autoinjector for subcutaneous administration of interferon β-1a (Rebif®) that includes several unique features designed to further reduce barriers to adherence, including a dosing log and adjustable comfort settings.

Role of differential expression of interferon receptor isoforms on the response of multiple sclerosis patients to therapy with interferon beta

The cytokine interferon (IFN)-β is successfully used in the treatment of multiple sclerosis. However, some patients fail to respond to therapy, probably due to different biological patterns that are of importance in influencing clinical response. A common mechanism involved in the modulation of responsiveness to cytokine is represented by regulation of their receptor expression through autocrine-ligand-mediated loops. Mechanistically, IFN-β exerts its biological effects through interaction with the IFN-α/-β-receptor (IFNAR), which then activates several transcription factors. IFNAR is composed of 2 chains, IFNAR-1 and IFNAR-2, which associate with IFN-β to form a ternary complex. The major ligand-binding subunit is IFNAR-2 and it exists in 3 mRNA splice variants, resulting in 2 transmembrane (IFNAR-2b and IFNAR-2c) isoforms and a soluble (IFNAR-2a) one. On the contrary, from normal cells only one IFNAR-1 isoform, with transcriptional capacity, was identified. In the past decades, considerable information has accumulated pertaining to the downregulation of the IFNAR complex in IFN-treated patients, but only a few studies have investigated the molecular events involved in this phenomenon. The intent of the present review is to place this receptor downregulation in the context of IFN-β therapy and of its clinical and biological outcomes in IFN-β-treated patients.

Improving compliance with interferon-beta therapy in patients with multiple sclerosis

Multiple sclerosis (MS) is an inflammatory demyelinating disease affecting young adults (with a peak of onset between the ages of 20 and 40 years). In 80-90% of cases, it is characterized by an early relapsing-remitting (RR) inflammatory phase, followed by a secondary progressive course in which disability progressively accumulates. Interferon-beta (IFNbeta) therapies represent the first-line treatment of RRMS. There are three IFNbeta formulations currently licensed for RRMS. Two are formulations of INFbeta-1a, one administered at a dosage of 30 mug intramuscularly weekly (Avonex(R)) and the other administered at a dosage of 22 or 44 microg subcutaneously (SC) three times a week (Rebif(R) 22 and 44). The third is a formulation of IFNbeta-1b, administered at a dosage of 250 microg SC every other day (Betaseron(R)). These treatments reduce the frequency of acute relapses and, to a lesser extent, disability progression. However, when starting an IFNbeta therapy, a treatment discontinuation rate ranging from 14% to 44% has to be expected. In a sizable proportion of patients, treatment suspension is caused by the occurrence of adverse effects (most commonly a flu-like syndrome and injection site reactions) and/or poor compliance. Individualized patient education and support are critical to improve adherence to therapy in the long term. Approaches aimed at reducing the proportion of subjects interrupting IFNbeta encompass both pharmacological and non-pharmacological interventions, and may involve several professional figures, such as the neurologist, the psychologist, the pharmacist, the physical and speech therapist, and the nurse. Recently, the development of new IFNbeta formulations, with reduced immunogenic potential, has offered an additional approach to improving patient adherence. Biferonex(R) is a pH neutral and human serum albumin-free IFNbeta-1a. A phase III, 2-year study of the product involving patients with RRMS has been conducted, but the results were not considered conclusive enough to allow approval in Europe. Rebif(R) New Formulation (RNF) is a formulation of INFbeta-1a that is not produced using fetal bovine serum and that does not have human serum albumin as an excipient. The formulation has been approved in Europe and an application for approval has been filed in the US. On the basis of the final analysis of a phase III trial, RNF showed higher tolerability, particularly in terms of injection site reactions, compared with the older formulation. Further studies assessing its usefulness as an alternative therapy for patients who are intolerant of other IFNbeta formulations are required.

The Rebif new formulation story: it's not trials and error

The rapid evolution of the biopharmaceutical industry and the development of innovative technologies have provided an opportunity to improve recombinant interferon (IFN)-beta formulations. A number of strategies have been developed to improve the stability, tolerability and immunogenicity of IFNbeta formulations that are used in the long-term treatment of patients with multiple sclerosis (MS). This review focuses on the production of recombinant IFNs and discusses the development of one such biopharmaceutical, Rebif New Formulation (RNF).RNF was developed with the aim of further improving the tolerability and immunogenicity of Rebif, an approved IFNbeta-1a formulation administered subcutaneously three times per week (sc tiw). To this end, numerous candidate drug vehicles and formulations were developed. However, unlike other formulations of IFNbeta, the new candidate formulations in this case were free from all serum-derived components. Specifically, each RNF candidate was free from human serum albumin and produced without fetal bovine serum. The physicochemical stability, injection-site tolerability, pharmacokinetic profile and immunogenic potential of each candidate formulation were systematically tested. This involved initial screening of a large pool of formulations for promising candidates. Two candidate formulations were selected and subjected to further, extensive evaluation.Ex vivo T-cell assays were used to compare the immunogenicity of RNF candidates with that of the current (at the time of writing) approved formulation and an IFNbeta standard. A single RNF candidate induced less T-cell activation, in terms of proliferation and proinflammatory cytokine secretion, than the other two formulations. The results provided ex vivo evidence of the improved immunogenic potential of RNF. A murine model was used to compare the relative immunogenicity of RNF in vivo with two approved formulations of IFNbeta-1a. Mice treated with RNF developed neutralising antibodies more slowly and produced lower titres than mice treated with equivalent doses of the current IFNbeta-1a sc tiw formulation or another approved IFNbeta-1a formulation administered intramuscularly once per week (Avonex). RNF also demonstrated better local tolerability than the current IFNbeta-1a sc tiw formulation after single subcutaneous doses in healthy volunteers. One RNF candidate was superior to the others in all preclinical and phase I studies, and was chosen as the final RNF. This formulation is currently undergoing assessment in a 96-week, phase IIIb clinical trial in patients with MS. This single-arm, open-label, multicentre study will compare the immunogenicity and tolerability of RNF with historical data on the current formulation; results of a 48-week, interim analysis indicate that RNF has improved local tolerability and immunogenicity compared with the current formulation. It is anticipated that the benefits of RNF will translate into an improved long-term benefit-to-risk profile. Further assessment of RNF and other MS drugs is ongoing with the aim of enhancing the therapeutic options available for patients with MS.