The STAR Study: A Real-World, International, Observational Study of the Safety and Tolerability of, and Adherence to, Serum-Free Subcutaneous Interferon β-1a in Patients With Relapsing Multiple Sclerosis

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.

A Prospective, Observational, Multicenter Study Assessing Adherence to Interferon Beta-1b Therapy and Patient Satisfaction Using the BETACONNECT Auto-Injector

Introduction

It is important to achieve good persistence and adherence to disease-modifying therapies (DMTs) to achieve the best outcomes in chronic diseases such as multiple sclerosis (MS). The BETACONNECT device is an electronic auto-injector for the DMT interferon beta-1b (Betaseron), designed to improve patients’ injection experience and to monitor adherence. This observational study aimed to assess patient adherence to and persistence with interferon beta-1b therapy as well as patient-reported satisfaction in a US population.

Methods

A prospective, observational, multicenter study was conducted in 146 adult patients with relapsing–remitting MS or clinically isolated syndrome, newly prescribed or currently established on interferon beta-1b therapy and naïve to the BETACONNECT device, and followed up during a 6-month observation period.

Results

Among the 91 patients who completed the study, the overall mean adherence rate was 82.5%, with 65.9% of patients adherent for at least 80% for the duration of the 6-month period. At 6 months, 98.9% of patients had less than a 60-day gap in therapy. Of the 115 patients who provided satisfaction data, 90.5% of patients were either very satisfied or satisfied with the BETACONNECT device.

Conclusion

This study shows that the BETACONNECT device was associated with high adherence to interferon beta-1b therapy in patients with MS. Patients also reported high degrees of satisfaction with the device. Therefore, this may be a viable delivery option to help with adherence and persistence, potentially leading to improved clinical outcomes.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40120-022-00323-1.

Do clinical trials for new disease modifying treatments include real world patients with multiple sclerosis?

We often see that clinical and demographic characteristics of real-world studies (RWS) do not differ from patients included in randomized controlled trials (RCT).

OBJECTIVE

to compare clinical and demographic aspects of patients included in RCT and RWS that evaluated new disease modifying treatment in multiple sclerosis (MS).

METHODS

a systematic non-language-restricted literature search of RCT and RWS that evaluated new disease modifying treatments (natalizumab, alemtuzumab, ocrelizumab, fingolimod, teriflunomide, dimethyl fumarate and cladribine) from January 2005 to January 2019. Demographic and clinical data were extracted, described and compared.

RESULTS

18 RCT and 73 RWS were included. We found no differences in clinical and demographic aspects between RCT and RWS except in the frequency of naïve patients included in RCT vs. RWS 65.6% (95%CI 52-74) vs. 36.4% (95%CI 21-46), respectively, (p = 0.013) at study entry, as well as for the inclusion of patients that used previous treatment 34.4% (95%CI 22-41) vs. 63.6% (95%CI 53-74) in RCT and RWS, respectively,(p = 0.007) at study entry.

CONCLUSION

We did not observe significant differences in most clinical and demographic aspects of included patients in RCT and RWS. Studies that include the full spectrum of MS patients followed in clinical practice are needed.

Patient needs and preferences in relapsing-remitting multiple sclerosis: A systematic review

BACKGROUND

Considering the multiple treatments approved for multiple sclerosis (MS) by the Food and Drug Administration (FDA) and European Medicines Agency (EMA), determining a treatment strategy for patients with clinically isolated syndrome (CIS) and relapsing-remitting MS (RRMS) can be challenging. To date, an overview of the needs and preferences of patients at each treatment decision-making moment is lacking. Therefore, the aim of this systematic review is to examine the existing literature about the needs and preferences of patients with CIS and RRMS when making treatment decisions.

METHODS

A systematic search was done using Embase, Medline, PsychINFO, Web of Science and Google Scholar. Eligibility criteria included whether the article described a study of adults with CIS/RRMS and reported patient needs or preferences regarding first-line disease modifying treatment (DMT) decisions. Publications were categorized by treatment decision: initiation of first DMT (D1), DMT adherence/discontinuation (D2a/D2b), and switch to a second DMT (D3). A separate category was created for stated preference studies such as discrete choice experiment methods to examine the relative importance of different treatment attributes. Publications were compared to identify key factors.

RESULTS

The search yielded 2789 articles after removal of duplicates and 434 full-text publications were reviewed for eligibility. Twenty-four articles fulfilled all criteria: n = 5 (D1), n = 12 (D2a), n = 13 (D2b), and n = 3 (D3); six articles studied more than one treatment decision. The need for social support is important during D1. The most commonly reported reasons for adherence/discontinuation/switch included forgetfulness, side-effects, and injection-related reasons. Eight articles described preference studies; the most important DMT attributes were efficacy, mode and frequency of administration, and side-effect profile.

CONCLUSIONS

Understanding the needs and preferences of CIS/RRMS patients regarding DMT attributes and non-treatment related attributes are important to improve treatment decision-making and reduce non-adherence. Studies are needed to understand patient preferences upon treatment initiation. Furthermore, preference studies should include attributes based on the patient perspective.

Interferons in the Treatment of Multiple Sclerosis: A Clinical Efficacy, Safety, and Tolerability Update

Interferon beta (IFNβ) was the first disease-modifying therapy available to treat multiple sclerosis (MS), providing patients with a treatment that resulted in reduced relapse rates and delays in the onset of disability. Four IFNβ drugs are currently approved to treat relapsing forms of MS: subcutaneous (SC) IFNβ-1b, SC IFNβ-1a, intramuscular IFNβ-1a, and, most recently, SC peginterferon beta-1a. Peginterferon beta-1a has an extended half-life and requires less frequent administration than other available treatments (once every 2 weeks vs every other day, 3 times per week, or weekly). Large randomized controlled clinical trials have confirmed the efficacy of interferons for the treatment of relapsing MS. The most frequent adverse events in patients receiving IFNs include injection site reactions and flu-like symptoms. Patient education and mitigation strategies are key to managing these adverse events and supporting therapy adherence. With fewer injections needed, peginterferon beta-1a is associated with less frequent discomfort, which may translate to improved adherence, a major factor in treatment efficacy. Because the available interferon therapies differ in administration route and frequency of injection, switching among these therapies may be a viable option for patients who experience issues with tolerability. Although a variety of disease-modifying therapies are now available to treat relapsing MS, the efficacy and long-term safety profile of interferons make them an important first-line option for treatment.

Cost-effectiveness of interferon therapy for multiple sclerosis in Peru: impact of treatment adherence

Objective

To analyse the cost-effectiveness (C-E) of interferon therapy for MS and the impact of adherence associated with a patient support programme (PSP).

Methods

Markov model was structured based on systematic review of the evidence and the opinion of local experts. The model has three health states: (1) Baseline treatment (BT), (2) Interferon-β (IFN) with patient support programme (PSP) and (3) IFN without PSP. Annual cycles were considered, with a time horizon of 30 years. The analysis perspective was based on the Ministry of Health (MoH).

Key findings

Interferon-β + PSP dominates the treatment of IFN without PSP. The incremental C-E rate (ICER) for IFN + PSP was estimated at S/. 26 408 per Quality Adjusted Life Year (QALY) in relation to BT. IFN without PSP was dominated by the IFN + PSP treatment. The cost per QALY of IFN + PSP was below the payment threshold in almost 100% of the model simulations. The acceptability curves show that the treatment with PSP + IFN is probabilistically more cost effective from a payment threshold of 1.25 annual Gross Domestic Product per capita (GDP-pc). The Tornado analysis for the ICER between IFN + PSP and BT shows that the most sensitive variables of the model are the relative risk (RR) for treatment adherence and the cost of IFN + PSP treatment.

Conclusion

The addition of a PSP had a significant effect on adherence and C-E of the intervention. The ICER for IFN + PSP was below 1.5 annual GDP-pc of payment threshold with an incremental cost near to 3 GDP-pc. IFN without PSP was dominated by the IFN + PSP.

Tolerability, treatment satisfaction and quality of life outcomes in stable multiple sclerosis patients switched from injectable therapies to auto injected intramuscular interferon beta 1a: The SFERA study

BACKGROUND

Interferon beta (IFNB) and Glatiramer acetate, long-term first line disease modifying treatments (DMTs) for multiple sclerosis (MS), have different injection frequencies crucial for injection site related side effects. We aimed at investigating whether switching to intramuscular IFNB-1a injected once/week with the Avonex®Pen™ device improves treatment tolerability and quality of life in stable MS patients.

METHODS

Clinically stable MS patients, whom their treating neurologist switched from high frequency injectable DMTs to weekly intramuscular IFNB-1a because of bothersome injection site reactions, were included. Injection site and systemic tolerability were measured by a composite 100 mm visual analogue scale at screening, months 4 and 12. Treatment satisfaction, quality of life, relapses and EDSS progression were also recorded. The primary endpoint was change in injection site tolerability from screening to Month 4. Descriptive statistics and Wilcoxon paired signed-rank tests were applied.

RESULTS

The median injection site tolerability and systemic tolerability were significantly improved at months 4 (n = 36) and 12 (n = 33) [change -51.60 (IQR: -60.13, -39.60) mm (p < 0.0001); -26.00 (-54.00, 2.25) mm (p = 0.002)]. Median treatment satisfaction was significantly improved at month 12 [change of 18.00 (2.00, 47.50) mm (p = 0.0003)]. Physical and mental components of the SF-36 did not change significantly, and 30/33 (90.9%) and 33/33 (100%) patients were free from relapses and EDSS progression at month 12.

CONCLUSIONS

Weekly intramuscular IFNB-1a may represent an alternative treatment option for clinically stable MS patients suffering from intolerable injection-related side effects under treatment with high frequency injectable DMTs.

Oral disease-modifying therapies for multiple sclerosis in the Middle Eastern and North African (MENA) region: an overview

BACKGROUND

The introduction of new disease-modifying therapies (DMTs) for remitting-relapsing multiple sclerosis (RRMS) has considerably transformed the landscape of therapeutic opportunities for this chronic disabling disease. Unlike injectable drugs, oral DMTs promote patient satisfaction and increase therapeutic adherence.

REVIEW

This article reviews the salient features about the mode of action, efficacy, safety, and tolerability profile of approved oral DMTs in RRMS, and reviews their place in clinical algorithms in the Middle East and North Africa (MENA) region. A systematic review was conducted using a comprehensive search of MEDLINE, PubMed, Cochrane Database of Systematic Reviews (period January 1, 1995-January 31, 2018). Additional searches of the American Academy of Neurology and European Committee for Treatment and Research in Multiple Sclerosis abstracts from 2012-2017 were performed, in addition to searches of the Food and Drug Administration and European Medicines Agency websites, to obtain relevant safety information on these DMTs.

CONCLUSIONS

Four oral DMTs: fingolimod, teriflunomide, dimethyl fumarate, and cladribine have been approved by the regulatory agencies. Based on the number needed to treat (NNT), the potential role of these DMTs in the management of active and highly active or rapidly evolving RRMS is assessed. Finally, the place of the oral DMTs in clinical algorithms in the MENA region is reviewed.

Adherence to Subcutaneous IFN β-1a in Multiple Sclerosis: Final Analysis of the Non-Interventional Study READOUTsmart Using the Dosing Log and Readout Function of RebiSmart®

INTRODUCTION

Patient adherence is a key determinant of treatment success in multiple sclerosis (MS). The RebiSmart^® autoinjector facilitates patient self-injection of subcutaneous interferon β-1a (sc IFN β-1a) and allows quantitative measurement of adherence via its automated dosing log. We evaluated patient adherence and patient-reported cognitive and health-economic outcomes over 2 years in patients using RebiSmart^®.

METHODS

In this non-interventional, single-arm study, enrolled patients were 12-65 years of age, had relapsing-remitting MS or a single demyelinating event, and had been prescribed 44 or 22 μg sc IFN β-1a. Quantitative adherence (proportion of scheduled injections administered) and qualitative adherence (proportion of weeks with treatment schedule correctly followed) were monitored over 2 years. Other end points included self-assessed adherence, patient-reported outcomes (fatigue, depression and quality of life), cognitive outcomes and health-economic outcomes.

RESULTS

A total of 368 of 392 (93.9%) enrolled patients were analyzed. Mean quantitative adherence was 85.3% overall (months 1-24), 89.6% for months 1-12 and 83.3% for months 13-24. No major impact on quantitative adherence was observed for sex, age (< 37 years vs. ≥ 37 years), prior medication or participation in the patient support program RebiSTAR^®. Mean qualitative adherence was 67.0% overall (months 1-24). Self-assessed adherence was reported as being higher than RebiSmart^®-monitored adherence. There was a trend toward more MS-related visits to physicians among patients with high adherence.

CONCLUSIONS

Patients using RebiSmart^® demonstrated high adherence to treatment that was associated with a slight improvement in information processing speed and working memory and an overall tendency for more intensive self-management.

FUNDING

Merck Serono GmbH, Germany, an affiliate of Merck KGaA, Darmstadt, Germany.

Real-World Effectiveness of Disease-Modifying Therapies in Korean Patients with Relapsing Multiple Sclerosis

BACKGROUND AND PURPOSE

This study assessed the long-term outcomes of disease-modifying therapies (DMTs) in Korean multiple sclerosis (MS) patients treated in real-world clinical settings in Korea.

METHODS

We retrospectively evaluated the medical records of 160 patients with an initial diagnosis of clinically isolated syndrome or relapsing-remitting MS who were treated for at least 2 years. A status of 3 for no evidence of disease activity (NEDA3) was defined as no relapse, disability progression, or active lesions in annual magnetic resonance imaging (MRI) evaluations.

RESULTS

Patients who were initially treated with interferon β (n=152), glatiramer acetate (n=6), or teriflunomide (n=2) were included. The mean disease duration was 8.2 years. Compared to pretreatment, annualized relapse rates were significantly reduced after treatment [from 1.0±0.8 to 0.2±0.4 (mean±standard deviation), p<0.001]. At the follow-up, 79 patients (49%) had changed their treatment regimen due to lack of efficacy (33%), side effects (14%), or other reasons (2%). Disability progression was observed in 18% of the patients over a mean treatment duration of 5.7 years. After 2 years, NEDA3 was observed in 38% of the patients. Loss of NEDA3 at 2 years was associated with long-term disability progression [odds ratio (OR)=17.975, p=0.003]. Poor response to first-line treatment was independently associated with a delay in treatment from disease onset (OR=1.238, p=0.049) and 10 or more brain lesions in the initial MRI (OR=3.648, p=0.047).

CONCLUSIONS

This study has provided real-world evidence that DMTs are effective in reducing disease activity and disability progression in Korean MS patients.

Real-world persistence with fingolimod for the treatment of multiple sclerosis: A systematic review and meta-analysis

OBJECTIVE

To systematically review reports of fingolimod persistence in the treatment of relapsing-remitting multiple sclerosis (RRMS) across data sources and practice settings, and to develop a consensus estimate of the 1-year real-world persistence rate.

METHODS

A systematic literature review was conducted (MEDLINE, EMBASE, and abstracts from selected conferences [2013-2015]) to identify observational studies reporting 1-year fingolimod persistence among adult patients with RRMS (sample size ≥50). A random-effects meta-analysis was performed to estimate a synthesized 1-year persistence rate and to assess heterogeneity across studies.

RESULTS

Of 527 publications identified, 25 real-world studies reporting 1-year fingolimod persistence rates were included. The studies included patients from different data sources (e.g., administrative claims, electronic medical records, or registries), used different definitions of persistence (e.g., based on prescriptions refills, patient report, or prescription orders), and spanned multiple geographic regions. Reported 1-year persistence rates ranged from 72%-100%, and exhibited statistical evidence of heterogeneity (I² = 93% of the variability due to heterogeneity across studies). The consensus estimate of the 1-year persistence rate was 82% (95% confidence interval: 79%-85%).

CONCLUSIONS

Across heterogeneous study designs and patient populations found in real-world studies, the consensus 1-year fingolimod persistence rate exceeded 80%, consistent with persistence rates identified in the recently-completed trial, PREFERMS.

Reasons for discontinuation of subcutaneous interferon β-1a three times a week among patients with multiple sclerosis: a real-world cohort study

Background

Continuation of interferon (IFN) β-based therapies is important for maximum treatment effectiveness in patients with multiple sclerosis (MS); however, few real-world data are available on discontinuation from IFN β. The aim of this cohort analysis was to estimate real-world discontinuation rates up to 3 years among MS patients in the United States taking subcutaneous (sc) IFN β-1a three times a week (tiw) and to identify whether the factors associated with discontinuation change over time.

Methods

Patient data were pooled from the MarketScan^© Commercial and Medicare Supplemental healthcare claims databases. Patients with ≥1 multiple sclerosis diagnosis who were sc IFN β-1a tiw naïve, had ≥1 year of continuous eligibility before treatment, and ≥1 prescription were followed from first prescription (index date) until date of discontinuation, switch, or end of observation. Treatment status was analysed at exactly 1, 2 or 3 years after index. Multivariable models were used to identify drivers of discontinuation.

Results

Data from 5956 patients were included; 2862 patients (48.1%) discontinued therapy. Discontinuation rates were 36.9% (1 year), 49.5% (2 years) and 55.8% (3 years). A greater proportion of discontinuing patients had poor adherence (<80% [94.0%] versus ≥80% [51.7%]) or were taking additional medication at follow-up versus the overall population. Factors independently associated with discontinuation irrespective of time on therapy were increasing number of magnetic resonance imaging scans (1 year adjusted odds ratio 1.45, 95% confidence interval 1.26–1.67; 2 years 1.18, 1.06–1.32; 3 years 1.20, 1.07–1.34) and adherence <80% versus ≥80% (1 year 180.95, 135.84–241.03; 2 years 135.80, 100.10–184.23; 3 years 174.89, 115.27–265.38). Factors associated only with early discontinuation (at 1 year) were ≥3 sets of laboratory investigations versus none (2.54, 1.20–5.38), and anxiolytic use at follow-up (1.40, 1.06–1.82). Factors associated only with later discontinuation (at 2 years and/or at 3 years) were antidepressant use at follow-up (2 years 1.46, 1.10–1.94) and greater number of relapses (2 years 1.60, 1.11–2.30; 3 years 2.31, 1.27–4.22).

Conclusions

Potential drivers of discontinuation change over time. Improved awareness of the drivers of discontinuation could lead to targeted interventions to improve adherence.

Electronic supplementary material

The online version of this article (doi:10.1186/s12883-017-0831-4) contains supplementary material, which is available to authorized users.

Persistency, medication prescribing patterns, and medical resource use associated with multiple sclerosis patients receiving oral disease-modifying therapies: a retrospective medical record review

Background

In the US, the approved multiple sclerosis (MS) oral disease-modifying therapies (ODMTs) are fingolimod (FTY), teriflunomide (TFN), and dimethyl fumarate (DMF). FTY and TFN are recommended with once-daily doses with no up-titration, whereas DMF treatment is recommended twice-daily (BID) and is initiated with a 7-day starter dose of 120 mg BID before up-titration to the maintenance dose of 240 mg BID. Limited information exists regarding real-world ODMT prescribing patterns to aid physician/patient decision-making.

Methods

Eligible patients for this retrospective medical record review were ≥18 years, had one visit related to ODMT initiation (index visit), and ≥1 visit within 12 months before and after the index visit. Primary objectives were to assess post-index ODMT persistency (i.e., discontinuation), prescribing patterns (medication switching, dose up-titrations, dose reduction, re-starts, and add-ons) and medical resource utilization (office-visits, MRI procedures, and mobility indicators) at distinct time windows of 3, 6, 9, and 12 months. Chi-square or Wilcoxon Rank Sum tests were used for 3-way ODMT group comparisons.

Results

Medical records of 293 MS-diagnosed patients using ODMTs were abstracted from 19 US-based neurology clinics between December 31, 2010 and June 30, 2014 (FTY: 101; DMF: 133; TFN: 59). Persistency rates among ODMT groups were similar. MS-related medication switching, dose reduction, re-starts, and add-ons were infrequently observed and were similar across ODMT groups. Of DMF patients with a confirmed starting dose of 120 mg BID with ≥12 months follow-up (n = 26), the percentage who were prescribed dose up-titrations to the recommended maintenance DMF dose was 23.1 % at 1–3 months, 26.9 % at 4–6 months, 42.3 % at 7–9 months, and 0 % at 10–12 months. There were no significant differences at any time window among the ODMT groups in the number of office visits or percent of patients receiving MRIs. Mobility indicator patterns (proportion of patients with abnormal gait, wheelchair use, etc.) were consistent over time.

Conclusions

There was no difference in persistency, prescribing patterns (medication switching, dose reduction, re-starts, and add-ons) or medical resource utilization (office-visits, MRI procedures, and mobility indicators) among the ODMTs. However, in a small sub-group of patients, delays of up to 9 months in DMF dose-up titration to the recommended maintenance dose were observed.

Electronic supplementary material

The online version of this article (doi:10.1186/s12883-016-0698-9) contains supplementary material, which is available to authorized users.

The importance of collecting structured clinical information on multiple sclerosis

BACKGROUND

Randomized controlled trials (RCTs) are the 'gold standard' in the generation of drug efficacy and safety evidence. However, enrolment criteria, timelines and atypical comparators of RCTs limit their relevance to standard clinical practice.

DISCUSSION

Real-world data (RWD) provide longitudinal information on the comparative effectiveness and tolerability of drugs, as well as their impact on resource use, medical costs, and pharmacoeconomic and patient-reported outcomes. This is particularly important in multiple sclerosis (MS), where economic treatment benefits of long-term disability reduction are a cornerstone of payer drug approvals - these are typically not examined in the RCT itself but modelled using real-world datasets. Importantly, surrogate markers used in RCTs to predict the prevention of long-term disability progression can only truly be assessed through RWD methodologies. We discuss the differences between RCTs and RWD studies, describe how RWD complements the evidence base from RCTs in MS, summarize the different methods of RWD collection, and explain the importance of structuring data analysis to avoid bias. Guidance on performing and identifying high-quality real-world evidence studies is also provided.

How many injections did you miss last month? A simple question to predict interferon β-1a adherence in multiple sclerosis

OBJECTIVES

Adherence to treatment is of utmost importance in multiple sclerosis (MS) to achieve full benefits from disease-modifying treatments. Thus, we investigated predictors of adherence to interferon β-1a.

METHODS

114 relapsing-remitting MS subjects were recruited and followed-up during 1.536 ± 0.961 years. RebiSmart® (Ares Trading SA, Coinsins, Switzerland), an electronic auto-injector, allows real-time recording of adherence which was retrospectively evaluated, and subjects were categorized accordingly: fully adherent (if no doses were missed), early or late missing (if missing the first dose during the first month of observation or later). The occurrence of clinical relapses and the annualized relapse rate (ARR) were prospectively recorded.

RESULTS

Adherence was 95.0 ± 9.0%. Early missing (n = 17, 14.9%) was more likely to be associated with the occurrence of a clinical relapse (OR = 4.155; p = 0.018), but not late missing (n = 54, 47.4%) (OR = 1.454; p = 0.408), as compared to fully adherent (n = 43, 37.7%). Adherence was lower in early missing, as compared to late missing (p < 0.001). The ARR was higher in early missing, as compared to late missing and to fully adherent (p < 0.001).

CONCLUSION

MS subjects missing an injection early presented lower adherence, and a fourfold chance of having a relapse, suggesting a simple way to assess and categorize adherence in a clinical, real-life setting, where lack of time often prevents more thorough evaluations.

Postmarketing Safety Profile of Subcutaneous Interferon Beta-1a Given 3 Times Weekly: A Retrospective Administrative Claims Analysis

BACKGROUND

Health insurance administrative claims databases represent a valuable source of information regarding the safety profile of marketed products as used in actual clinical practice in a broader range of patients than that assessed in clinical trials. Interferon beta-1a administered subcutaneously 3 times weekly (IFN β-1a SC tiw), which was approved in 2002 by the FDA for the treatment of relapsing-remitting multiple sclerosis (MS), has over a decade of postmarketing experience. To date, however, its postmarketing safety profile has not been described using a real-world evidence source such as administrative claims data.

OBJECTIVE

To describe the safety profile of IFN β-1a SC tiw as presented in its U.S. prescribing information (PI) for patients with MS initiating IFN β-1a SC tiw therapy using data from U.S. health care administrative claims databases.

METHODS

This study featured an observational and retrospective "new start" cohort design using data from the Truven MarketScan Commercial and Medicare Supplemental health care administrative claims databases. Patients were eligible for inclusion if they were aged ≥ 18 years; had ≥ 1 diagnosis for MS recorded between January 1, 2006, and December 31, 2012; had ≥ 2 prescriptions for IFN β-1a SC tiw; and had ≥ 90 days of continuous eligibility pre-index date and ≥ 180 days of continuous eligibility post-index date. Patients with a prescription for IFN β-1a SC tiw without a MS diagnosis were excluded. Patients were followed from first prescription for IFN β-1a SC tiw (index date) until date of therapy switch or discontinuation, end of insurance eligibility, or end of observation period. Adverse events (AEs) examined were those listed in the Warnings and Precautions, Adverse Reactions, and Postmarketing Experience sections of the 2014 U.S. PI. Outcomes of interest were identified at the Medical Dictionary for Regulatory Activities (version 17.1) Preferred Term level and then coded to the corresponding ICD-9-CM criteria. Descriptive analyses of patient demographic, health status, health care utilization, and adherence status were performed, and incidence rates (IRs) per 100 person-years of labeled AEs with corresponding 95% CIs were calculated. The IR calculation was based on events that presented after therapy initiation and that were not present in the 90-day pre-index period.

RESULTS

The top 6 AEs included influenza-like symptoms (IR = 15.65, 95% CI = 14.96-16.36); malaise (IR = 15.33, 95% CI = 14.65-16.04; fatigue (IR = 15.02, 95% CI = 14.35-15.72); abdominal pain (IR = 10.18, 95% CI = 9.67-10.70); chest pain (IR = 8.48, 95% CI = 8.03-8.95); and depression (IR = 7.75, 95% CI = 7.32-8.20). In contrast, the 6 lowest IRs were for maculo-papular rash (IR = 0.01, 95% CI = 0.00-0.04; injection-site necrosis (IR = 0.01, 95% CI = 0.00-0.03); erythema multiforme (IR = 0.01, 95% CI = 0.00-0.04); hypoesthesia (IR = 0.00, 95% CI = 0.00-0.02); Stevens-Johnson Syndrome (IR = 0.00, 95% CI = 0.00-0.02); and xerophthalmia (IR = 0.00, 95% CI = 0.00-0.02).

CONCLUSIONS

Study results show strong convergence between the real-world safety profile of IFN β-1a SC tiw and its U.S. label. Our findings demonstrate the value of using real-world evidence obtained from administrative claims to complement clinical trial and postmarketing surveillance data in order to characterize the safety profile of established products, such as IFN β-1a SC tiw, in the postmarketing context.