A 8-year retrospective cohort study comparing Interferon-β formulations for relapsing-remitting multiple sclerosis

Interferon beta for the treatment of multiple sclerosis in the Campania Region of Italy: Merging the real-life to routinely collected healthcare data

Background

We aim to overcome limitations of previous clinical and population-based studies by merging a clinical registry to routinely-collected healthcare data, and to specifically describe differences in clinical outcomes, healthcare resource utilization and costs between interferon beta formulations for multiple sclerosis (MS).

Methods

We included 850 patients with MS treated with interferon beta formulations, from 2015 to 2019, seen at the MS Clinical Care and Research Centre (Federico II University of Naples, Italy) and with linkage to routinely-collected healthcare data (prescription data, hospital admissions, outpatient services). We extracted and computed clinical outcomes (relapses, 6-month EDSS progression using a roving EDSS as reference), persistence (time spent on a specific interferon beta formulation), adherence (medication possession ratio (MPR)), healthcare resource utilization and costs (annualized hospitalization rate (AHR), costs for hospital admissions and DMTs). To evaluate differences between interferon beta formulations, we used linear regression (adherence), Poisson regression (AHR), mixed-effect regression (costs), and Cox-regression models (time varying variables); covariates were age, sex, treatment duration, baseline EDSS and adherence.

Results

Looking at clinical outcomes, rates of relapses and EDSS progression were lower than studies run on previous cohorts; there was no differences in relapse risk between interferon beta formulations. Risk of discontinuation was higher for Betaferon®/Extavia® (HR = 3.28; 95%CI = 2.11, 5.12; p<0.01). Adherence was lower for Betaferon®/Extavia® (Coeff = -0.05; 95%CI = -0.10, -0.01; p = 0.02), and Avonex® (Coeff = -0.06; 95%CI = -0.11, -0.02; p<0.01), when compared with Rebif® and Plegridy® (Coeff = 0.08; 95%CI = 0.01, 0.16; p = 0.02). AHR and costs for MS hospital admissions were higher for Betaferon®/Extavia® (IRR = 2.38; 95%CI = 1.01, 5.55; p = 0.04; Coeff = 14.95; 95%CI = 1.39, 28.51; p = 0.03).

Conclusions

We have showed the feasibility of merging routinely-collected healthcare data to a clinical registry for future MS research, and have confirmed interferon beta formulations play an important role in the management of MS, with positive clinical outcomes. Differences between interferon beta formulations are mostly driven by adherence and healthcare resource utilization.

Persistence, adherence, healthcare resource utilisation and costs for interferon Beta in multiple sclerosis: a population-based study in the Campania region (southern Italy)

Background

To differentiate five formulations of Interferon Beta for the treatment of multiple sclerosis (MS) in clinical practice, by analysing persistence, adherence, healthcare resource utilisation and costs at population level.

Methods

In this population-based study, we included individuals with MS living in the Campania Region of Italy from 2015 to 2017, on treatment with intramuscular Interferon Beta-1a (Avonex® = 618), subcutaneous pegylated Interferon Beta-1a (Plegridy® = 259), subcutaneous Interferon Beta-1a (Rebif® = 1220), and subcutaneous Interferon Beta-1b (Betaferon® = 348; and Extavia® = 69). We recorded healthcare resource utilisation from administrative databases (hospital discharges, drug prescriptions, MS-related outpatients), and derived costs from the Regional formulary. We classified hospital admissions into MS-related and non-MS-related. Persistence (time to switch to other disease modifying treatments (DMTs)), and adherence (medication possession ratio (MPR) = medication supply obtained/medication supply expected during follow-up period) were calculated.

Results

Patients treated with Rebif® were younger, when compared with other Interferon Beta formulations (p < 0.01). The probability of switching to other DMTs was 60% higher for Betaferon®, 90% higher for Extavia®, and 110% higher for Plegridy®, when compared with Rebif® (p < 0.01). Plegridy® presented with 7% higher adherence (p < 0.01), and Betaferon® with 3% lower adherence (p = 0.03), when compared with Rebif®. The probability of MS-related hospital admissions was 40% higher in Avonex® (p = 0.03), 400% higher in Betaferon® (p < 0.01), and 60% higher in Plegridy® (p = 0.04), resulting into higher non-DMT-related costs, when compared with Rebif®.

Discussion

Interferon Beta formulations presented with different prescription patterns, persistence, adherence, healthcare resource utilisation and costs, with Rebif® being used in younger patients and with less MS-related hospital admissions.

Multiple Sclerosis in the Campania Region (South Italy): Algorithm Validation and 2015-2017 Prevalence

We aim to validate a case-finding algorithm to detect individuals with multiple sclerosis (MS) using routinely collected healthcare data, and to assess the prevalence of MS in the Campania Region (South Italy). To identify individuals with MS living in the Campania Region, we employed an algorithm using different routinely collected healthcare administrative databases (hospital discharges, drug prescriptions, outpatient consultations with payment exemptions), from 1 January 2015 to 31 December 2017. The algorithm was validated towards the clinical registry from the largest regional MS centre (n = 1460). We used the direct method to standardise the prevalence rate and the capture-recapture method to estimate the proportion of undetected cases. The case-finding algorithm including individuals with at least one MS record during the study period captured 5362 MS patients (females = 64.4%; age = 44.6 ± 12.9 years), with 99.0% sensitivity (95% CI = 98.3%, 99.4%). Standardised prevalence rate per 100,000 people was 89.8 (95% CI = 87.4, 92.2) (111.8 for females [95% CI = 108.1, 115.6] and 66.2 for males [95% CI = 63.2, 69.2]). The number of expected MS cases was 2.7% higher than cases we detected. We developed a case-finding algorithm for MS using routinely collected healthcare data from the Campania Region, which was validated towards a clinical dataset, with high sensitivity and low proportion of undetected cases. Our prevalence estimates are in line with those reported by international studies conducted using similar methods. In the future, this cohort could be used for studies with high granularity of clinical, environmental, healthcare resource utilisation, and pharmacoeconomic variables.

Sample Size for Oxidative Stress and Inflammation When Treating Multiple Sclerosis with Interferon-β1a and Coenzyme Q10

Studying multiple sclerosis (MS) and its treatments requires the use of biomarkers for underlying pathological mechanisms. We aim to estimate the required sample size for detecting variations of biomarkers of inflammation and oxidative stress. This is a post-hoc analysis on 60 relapsing-remitting MS patients treated with Interferon-β1a and Coenzyme Q10 for 3 months in an open-label crossover design over 6 months. At baseline and at the 3 and 6-month visits, we measured markers of scavenging activity, oxidative damage, and inflammation in the peripheral blood (180 measurements). Variations of laboratory measures (treatment effect) were estimated using mixed-effect linear regression models (including age, gender, disease duration, baseline expanded disability status scale (EDSS), and the duration of Interferon-β1a treatment as covariates; creatinine was also included for uric acid analyses), and were used for sample size calculations. Hypothesizing a clinical trial aiming to detect a 70% effect in 3 months (power = 80% alpha-error = 5%), the sample size per treatment arm would be 1 for interleukin (IL)-3 and IL-5, 4 for IL-7 and IL-2R, 6 for IL-13, 14 for IL-6, 22 for IL-8, 23 for IL-4, 25 for activation-normal T cell expressed and secreted (RANTES), 26 for tumor necrosis factor (TNF)-α, 27 for IL-1β, and 29 for uric acid. Peripheral biomarkers of oxidative stress and inflammation could be used in proof-of-concept studies to quickly screen the mechanisms of action of MS treatments.

The long-term effects of disease modifying therapies on disability in people living with multiple sclerosis: A systematic review and meta-analysis

BACKGROUND

Disease modifying therapies (DMT) are a common medication class for treating people living with MS. However, although treatment with DMT can extend over more than a decade, little is known about their long-term effects. Here, we systematically review long-term (≥4 years) studies on the effect of DMT on disability progression and relapse in people living with MS.

METHODS

We searched the EMBASE and Medline databases in January 2018, using search terms that included DMT and relevant outcome measures. Two authors screened all resulting studies and evaluated the risk of bias of included studies using the ROBINS-I tool for non-randomized studies. Where there was sufficient data, we performed meta-analyses using RevMan 5. Studies that could not be included in a meta-analysis were included in data synthesis.

RESULTS

Our search returned 7,766 unique articles for review. After screening, 18 articles were included. Follow-up in these studies ranged from a mean of 3.9 years to a median of 17.8 years. Fifteen (83.3%) of the included studies had a moderate risk of bias and three (16.7%) had a serious risk of bias. Meta-analysis showed that DMT significantly reduced the risk of EDSS 6.0 and SPMS compared to no treatment.

CONCLUSION

There is some evidence that long-term treatment with interferon beta reduces the risk of EDSS 6.0 and SPMS compared to no treatment or placebo. More work is needed on the effect of second generation DMT and the relative effect of DMT on health outcomes.

An Overview of Therapeutic Options in Relapsing-remitting Multiple Sclerosis

Multiple sclerosis (MS) is a chronic disorder of the central nervous system (CNS). MS affects 2.1 million individuals every year and is also considered a major cause of economic health burden around the world. Genetics and environmental factors both play a role in the pathogenesis of MS by activating the immune response and causing inflammation. Patients with MS can have various clinical courses, but the most common pattern seen is relapsing-remitting multiple sclerosis (RRMS). Multiple therapeutic options have been studied to prevent RRMS patients from frequent relapses. The oldest and most frequently used medication for MS is interferon beta, either used alone or as add-on therapy with other drugs. Newer treatment options that have been recently approved to control MS symptoms and suppress the inflammation are glatiramer acetate and siponimod. Infusion therapies consisting of monoclonal antibodies and immunosuppressive drugs have also been studied in the recent past. Some trials have been conducted on the use of stem cells for RRMS patients. We have briefly discussed all treatment options and the response of RRMS patients in multiple trials.

COST-UTILITY ANALYSIS OF MULTIPLE SCLEROSIS TREATMENT IN THAILAND

OBJECTIVES

Although interferon beta-1a (IFNß-1a), 1b (IFNß-1b), and fingolimod have been approved as multiple sclerosis (MS) treatments, they have not yet been included on the National List of Essential Medicines (NLEM) formulary in Thailand. This study aimed to evaluate the cost-utility of MS treatments compared with best supportive care (BSC) based on a societal perspective in Thailand.

METHODS

A Markov model with cost and health outcomes over a lifetime horizon with a 1-month cycle length was conducted for relapsing-remitting MS (RRMS) patients. Cost and outcome data were obtained from published studies, collected from major MS clinics in Thailand and a discount rate of 3 percent was applied. The incremental cost-effectiveness ratio (ICER) was calculated and univariate and probabilistic sensitivity analyses were performed.

RESULTS

When compared with BSC, the ICERs for patients with RRMS aged 35 years receiving fingolimod, IFNβ-1b, and IFNβ-1a were 33,000, 12,000, and 42,000 US dollars (USD) per quality-adjusted life-year (QALY) gained, respectively. At the Thai societal willingness to pay (WTP) threshold of USD 4,500 per QALY gained, BSC had the highest probability of being cost-effective (49 percent), whereas IFNβ-1b and fingolimod treatments showed lower chance being cost-effective at 25 percent and 18 percent, respectively.

CONCLUSIONS

Compared with fingolimod and interferon treatments, BSC remains to be the most cost-effective treatment for RRMS in Thailand based on a WTP threshold of USD 4,500 per QALY gained. The results do not support the inclusion of fingolimod or interferon in the NLEM for the treatment of RRMS unless their prices are decreased or special schema arranged.