Identification of Substandard Medicines via Disproportionality Analysis of Individual Case Safety Reports.

INTRODUCTION: The distribution and use of substandard medicines (SSMs) is a public health concern worldwide. The detection of SSMs is currently limited to expensive large-scale assay techniques such as high-performance liquid chromatography (HPLC). Since 2013, the Pharmacovigilance Department at Novartis Pharma AG has been analyzing drug-associated adverse events related to 'product quality issues' with the aim of detecting defective medicines using spontaneous reporting. The method of identifying SSMs with spontaneous reporting was pioneered by the Monitoring Medicines project in 2011. METHODS: This retrospective review was based on data from the World Health Organization (WHO) Global individual case safety report (ICSR) database VigiBase® collected from January 2001 to December 2014. We conducted three different stratification analyses using the Multi-item Gamma Poisson Shrinker (MGPS) algorithm through the Oracle Empirica data-mining software. In total, 24 preferred terms (PTs) from the Medical Dictionary for Regulatory Activities (MedDRA®) were used to identify poor-quality medicines. To identify potential SSMs for further evaluation, a cutoff of 2.0 for EB05, the lower 95% interval of the empirical Bayes geometric mean (EBGM) was applied. We carried out a literature search for advisory letters related to defective medicinal products to validate our findings. Furthermore, we aimed to assess whether we could confirm two SSMs first identified by the Uppsala Monitoring Centre (UMC) with our stratification method. RESULTS: The analysis of ICSRs based on the specified selection criteria and threshold yielded 2506 hits including medicinal products with an excess of reports of product quality defects relative to other medicines in the database. Further investigations and a pilot study in five authorized medicinal products (proprietary and generic) licensed by a single marketing authorization holder, containing valsartan, methylphenidate, rivastigmine, clozapine, or carbamazepine, were performed. This resulted in an output of 23 potential SSMs. The literature search identified two communications issued to health professionals concerning a substandard rivastigmine patch, which validated our initial findings. Furthermore, we identified excess reporting of product quality issues with an ethinyl estradiol/norgestrel combination and with salbutamol. These were categorized as confirmed clusters of substandard/spurious/falsely labelled/falsified/counterfeit (SSFFC) medical products by the UMC in 2014. CONCLUSION: This study illustrates the value of data mining of spontaneous adverse event reports and the applicability of disproportionality analysis to identify potential SSMs.

Cardiac Effects of Siponimod (BAF312) Re-initiation After Variable Periods of Drug Discontinuation in Healthy Subjects.

PURPOSE: The goal of this study was to investigate the effect of siponimod treatment re-initiation on the initial negative chronotropic effects and cardiac rhythm after variable drug discontinuation periods. METHODS: This partially double-blind, randomized, placebo-controlled study was conducted in healthy subjects. Siponimod doses (0.5-4.0 mg) and placebo were evaluated in combination with drug discontinuation periods ranging from 48 to 192 hours. Twelve-lead Holter ECGs were performed from 1.5 hours before until 24 hours after single-dose re-initiation. Atrioventricular blocks (AVBs) and sinus pauses (RR >2 seconds) were categorized according to dose level, discontinuation period, and resting and nonresting hours. FINDINGS: Of the enrolled 138 subjects, 117 were evaluated. Demographic and baseline characteristics were comparable between the treatment groups. Subjects rechallenged at the combination of 4 mg/192 hours (highest investigated dose and longest discontinuation period [7 missed doses]) exhibited the highest decrease in pooled, placebo-adjusted heart rate (HR) of 14.53 beats/min. The magnitude of the negative chronotropic effect of siponimod re-initiation was dependent on both dose and duration of treatment discontinuation. Regardless of the dose, the placebo-adjusted HR reduction at re-initiation of drug treatment after up to 96 hours of drug discontinuation remained <10 beats/min. Except for 1 outlier for HR decrease under the 96-hour/placebo combination, no outliers were observed for any combination up to and including the 96-hour discontinuation periods. Most of the AVBs and sinus pauses were observed during nocturnal hours concurrent with increased vagal tone. All detected AVBs and sinus pauses were asymptomatic and not considered clinically relevant. IMPLICATIONS: Siponimod could be safely re-initiated without retitration after drug discontinuation periods up to 96 hours. Retitration is required if patients miss ≥ 4 consecutive doses.

Effects of Therapeutic and Supratherapeutic Doses of Siponimod (BAF312) on Cardiac Repolarization in Healthy Subjects.

PURPOSE: The International Conference on Harmonisation E14 guideline mandates an intensive cardiac safety evaluation in a clinical thorough QT study, typically in healthy subjects, for all new non-antiarrhythmic drugs with systemic bioavailability. This thorough QT study investigated the effects of therapeutic (2 mg) and supratherapeutic (10 mg) doses of siponimod (BAF312) on cardiac repolarization in healthy subjects. METHODS: The study was a randomized, double-blind, parallel-group, placebo- and moxifloxacin-controlled, multiple oral dose study. Eligible subjects were randomly assigned to 3 groups to receive siponimod (up-titration to 2 and 10 mg over 18 days), placebo (Days -1 to 18), or moxifloxacin 400 mg Days 10 and 18). Triplicate ECGs were extracted at prespecified time points from Holter ECGs recorded from 1 hour predose until 24 hours postdose at baseline and on-treatment assessment Days 10 and 18. The primary pharmacodynamic variable was the time-matched, placebo-corrected, baseline-adjusted mean QTcF (ΔΔQTcF) at steady-state conditions. In addition, the pharmacokinetic parameters of siponimod and its main circulating metabolite M3 and its metabolite M5 were evaluated. FINDINGS: Of the 304 enrolled subjects, 281 (92.4%) were included in the pharmacodynamic analysis and 270 (88.8%) completed the study. The upper bounds of the 2-sided 90% confidence intervals (CIs) for ΔΔQTcF at both siponimod doses were within the regulatory threshold of 10 milliseconds (ms) at all predefined on-treatment time points, with the absence of any dose-related effects. The highest observed upper limits of the 2-sided 90% CIs of 9.8 and 9.6 ms for therapeutic and supratherapeutic doses, respectively, were both observed at 3 hours postdose. No treatment-emergent QTc values >480 ms and no QTc increases of >60 ms from baseline were observed. Similar results were obtained with individualized heart rate correction of cardiac repolarization (QTcI). Assay validity was demonstrated by maximum ΔΔQTcF of >5 ms after 400 mg moxifloxacin on both on-treatment assessment days. The selected supratherapeutic dose produced approximately 5-fold higher exposures (Cmax and AUC) than the therapeutic dose, and was considered appropriate to investigate the effects of siponimod on QT/QTc at substantial multiples of the anticipated maximum therapeutic exposure. IMPLICATIONS: The findings provide evidence that siponimod is not associated with a significant arrhythmogenic potential related to QT prolongation.