Pharmacodynamic biomarkers of long-term interferon beta-1a therapy in REFLEX and REFLEXION

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.

Serum RNase L levels in patients with chronic hepatitis B virus infection

BACKGROUND/AIMS

Chronic hepatitis B virus (HBV) infection still poses a major threat to global health. Oligoadenylate synthetase-ribonuclease L (RNase L) antiviral pathway is one of interferon-induced antiviral effectors. The relationship between RNase L and HBV has never been investigated and we aim to examine the serum RNase L levels in patients with different stages of chronic HBV infection.

METHODS

The patients were enrolled from 1985 to 2000, who had been HBsAg positive for longer than 6 months, at the National Taiwan University Hospital. In total, 426 patients with chronic HBV infection were included in this study, including 135 inactive carriers, 148 cirrhosis, and 143 hepatocellular carcinoma (HCC) cases.

RESULTS

The RNase L levels increase as the disease severity increases. Higher RNase L levels were associated with higher HBV viral load, and the HBV-RNase L relationship was replaced by the disease severity status when adding disease status into the model. Compared with inactive carriers, the risk of liver cirrhosis was 60-fold (odds ratio = 60.8, 95% confidence interval = 3.49-1061) with the highest quintile of RNase L levels, after the adjustment of HBV DNA. The dose-response trend was statistically significant with quintiles and one increment of RNase L level in relation to liver cirrhosis. Similar results were found when HCC was compared with inactive carriers, while there was no association when compared between liver cirrhosis and HCC.

CONCLUSIONS

A positive relationship between serum RNase L and HBV viral titers or advanced disease status is uncovered in this study. Further investigation in this area may provide more details of an innate immune response for HBV and opportunity for novel therapeutic strategy.

Interferon beta-1a sc at 25 years: a mainstay in the treatment of multiple sclerosis over the period of one generation

INTRODUCTION

Interferon beta (IFN beta) preparations are an established group of drugs used for immunomodulation in patients with multiple sclerosis (MS). Subcutaneously (sc) applied interferon beta-1a (IFN beta-1a sc) has been in continuous clinical use for 25 years as a disease-modifying treatment.

AREAS COVERED

Based on data published since 2018, we discuss recent insights from analyses of the pivotal trial PRISMS and its long-term extension as well as from newer randomized studies with IFN beta-1a sc as the reference treatment, the use of IFN beta-1a sc across the patient life span and as a bridging therapy, recent data regarding the mechanisms of action, and potential benefits of IFN beta-1a sc regarding vaccine responses.

EXPERT OPINION

IFN beta-1a sc paved the way to effective immunomodulatory treatment of MS, enabled meaningful insights into the disease process, and remains a valid therapeutic option in selected vulnerable MS patient groups.

Evaluating the Utility of Proteomics for the Identification of Circulating Pharmacodynamic Biomarkers of IFNβ-1a Biologics

Proteomics has the potential to identify pharmacodynamic (PD) biomarkers for similarity assessment of proposed biosimilars without relying on clinical efficacy end points. In this study, with 36 healthy participants randomized to therapeutic doses of interferon-beta 1a products (IFNβ-1a) or pegylated-IFNβ-1a (pegIFNβ-1a) approved to treat multiple sclerosis or placebo, we evaluated the utility of a proteomic assay that profiles > 7,000 plasma proteins. IFNβ-1a and pegIFNβ-1a resulted in 248 and 528 differentially expressed protein analytes, respectively, between treatment and placebo groups over the time course. Thirty-one proteins were prioritized based on a maximal fold change ≥ 2 from baseline, baseline adjusted area under the effect curve (AUEC) and overlap between the 2 products. Of these, the majority had a significant AUEC compared with placebo in response to either product; 8 proteins showed > 4-fold maximal change from baseline. We identified previously reported candidates, beta-2microglobulin and interferon-induced GTP-binding protein (Mx1) with ~ 50% coefficient of variation (CV) for AUEC, and many new candidates (including I-TAC, C1QC, and IP-10) with CVs ranging from 26%-129%. Upstream regulator analysis of differentially expressed proteins predicted activation of IFNβ1 signaling as well as other cytokine, enzyme, and transcription signaling networks by both products. Although independent replication is required to confirm present results, our study demonstrates the utility of proteomics for the identification of individual and composite candidate PD biomarkers that may be leveraged to support clinical pharmacology studies for biosimilar approvals, especially when biologics have complex mechanisms of action or do not have previously characterized PD biomarkers.

Pharmacokinetics/pharmacodynamics by race: Analysis of a peginterferon β-1a phase 1 study

BACKGROUND

Black/African American participants are underrepresented in clinical trials for multiple sclerosis but can experience a greater burden of disease than other racial groups in the United States. A phase 1, open-label, crossover study that demonstrated bioequivalence of subcutaneous and intramuscular injection of peginterferon β-1a in healthy volunteers enrolled similar proportions of Black and White participants, enabling a post hoc subgroup analysis comparing these groups.

METHODS

Peginterferon β-1a (125 μg) was administered by subcutaneous or intramuscular injection, followed by a washout period before a second injection using the alternative method. The primary pharmacokinetic and pharmacodynamic endpoints were maximum observed concentration (C_max) and area under the concentration-time curve from hour 0 to infinity (AUC_inf) of study drug and serum concentration of neop-terin, respectively. Safety and tolerability were included as secondary endpoints.

FINDINGS

This analysis included 70 (51.5%) Black and 59 (43.3%) White participants. Peginterferon β-1a C_max was 29.8% higher in Black than in White participants following subcutaneous administration but was similar following intramuscular administration. Mean AUC_inf was 31.0% and 11.8% greater in Black than in White participants with subcutaneous and intramuscular administration, respectively. Pharmacodynamics and safety signals were similar between groups, although Black participants reported numerically fewer adverse events.

CONCLUSIONS

No clinically meaningful differences were identified between Black and White participants related to peginterferon β-1a administration, supporting the approved dose of 125 μg/mL peginterferon β-1a. Future clinical studies should include sufficiently diverse populations to ensure accurate assessments of treatment response.

FUNDING

Funding for medical writing support was provided by Biogen (Cambridge, MA, USA).