| Literature DB >> 25564333 |
Deborah Layton1, Saad A W Shakir.
Abstract
The evolving regulatory landscape has heightened the need for innovative, proactive, efficient and more meaningful solutions for 'real-world' post-authorization safety studies (PASS) that not only align with risk management objectives to gather additional safety monitoring information or assess a pattern of drug utilization, but also satisfy key regulatory requirements for marketing authorization holder risk management planning and execution needs. There is a need for data capture across the primary care and secondary care interface, or for exploring use of new medicines in secondary care to support conducting PASS. To fulfil this need, event monitoring has evolved. The Specialist Cohort Event Monitoring (SCEM) study is a new application that enables a cohort of patients prescribed a medicine in the hospital and secondary care settings to be monitored. The method also permits the inclusion of a comparator cohort of patients receiving standard care, or another counterfactual comparator group, to be monitored concurrently, depending on the study question. The approach has been developed in parallel with the new legislative requirement for pharmaceutical companies to undertake a risk management plan as part of post-authorization safety monitoring. SCEM studies recognize that the study population comprises those patients who may have treatment initiated under the care of specialist health care professionals and who are more complex in terms of underlying disease, co-morbidities and concomitant medications than the general disease population treated in primary care. The aims of this paper are to discuss the SCEM new-user study design, rationale and features that aim to address possible bias (such as selection bias) and current applications.Entities:
Mesh:
Year: 2015 PMID: 25564333 PMCID: PMC4328122 DOI: 10.1007/s40264-014-0260-x
Source DB: PubMed Journal: Drug Saf ISSN: 0114-5916 Impact factor: 5.606
Fig. 1Aims of post-authorization safety studies (PASS) [1]. Within non-interventional PASS conducted in a ‘real-world’ setting, usual clinical course of care applies and receipt of treatment by a patient is not a condition of participation within a PASS. A PASS must address at least one of the aims listed in the figure
Characteristics of Specialist Cohort Event Monitoring (SCEM) design
| Study characteristic | SCEM |
|---|---|
| Setting | Secondary care |
| HCPs | Specialists |
| Design | Observational |
| Treatment | Naturalistic |
| Period of observation | Immediately post-start of treatment; the duration depends on the study question(s) |
| Ethics | Patient consent required |
| Risk level of patient | More likely to capture high-risk patients with more severe disease |
| Data source | Secondary use of data from existing medical records |
| Comparator | Standard care, other or none; the choice depends on the study question |
HCP health care professional
Fig. 2Possible immortal time in observational studies using primary care medical records data. Immortal time bias is introduced in cohort studies using primary care medical records when the period of immortal time is excluded from the analysis because the start of follow-up for new users whose treatment is initiated in secondary care is defined by the start of treatment in primary care, not by the start of treatment in secondary care. GP primary care physician
Fig. 3Process flow of a Specialist Cohort Event Monitoring (SCEM) study. GP primary care physician
Examples of applications of Specialist Cohort Event Monitoring (SCEM) methodology
| ENCEPP e-register of PASS | Rationale and background | Research question | Study design | Setting, timeframe and size | Subject sampling | Data analysis applications |
|---|---|---|---|---|---|---|
| Observational Assessment of Safety in Seroquel (OASIS) [ | Post-approval RMP commitment for further understanding of safety during titration and at higher doses (>600 mg/day) of the XL formulation of quetiapine fumarate (Seroquel XLTM) | To examine short-term (up to 12-week) safety and use of Seroquel XL™ newly initiated in patients with a clinical diagnosis of schizophrenia or manic episodes associated with bipolar disorder in the mental health care trust setting | Observational, population-based cohort design Two waves of data collection (at baseline and 12 weeks post-index date) Quetiapine IR used in referent cohort | Mental health trust setting in secondary care; patients recruited from February 2010 to December 2012; evaluable patients with baseline data ( | Accessible target patient population was treated by specialist HCPs in psychiatry Sampling supported by MHRN CRN | Univariate analysis to explore impact of formulation and dose on identified risks and for general surveillance Time-to-event analysis to characterize pattern of hazard over time for important identified risks |
| Observational Safety Evaluation of Asenapine (OBSERVA) [ | Post-authorization commitment requested by the CHMP to further investigate the safety profile of asenapine (Sycrest™) in clinical practice | To monitor short-term (12-week) use and safety of asenapine prescribed to asenapine-naïve (new-user) patients for treatment of moderate to severe manic episodes associated with bipolar I disorder and other psychiatric disorders | Observational, population-based, single-exposure cohort design Two waves of data collection (at baseline and 12 weeks post-index date) | Mental health trust setting in secondary care; patients recruited over 3 years from December 2012 Per-protocol sample size ( | Accessible target patient population was treated by specialist HCPs in psychiatry Sampling supported by MHRN CRN | Association between oral events (oral and pharyngeal hypoaesthesia, oropharyngeal swelling) and starting treatment will be examined using the self-controlled case series method [ |
| Rivaroxaban Observational Safety Evaluation (ROSE) study [ | Post-authorization commitment requested by the CHMP to further investigate the safety profile of rivaroxaban (Xarelto™) in clinical practice | To monitor the short-term (12-week) use and safety profile of rivaroxaban prescribed to new-user (rivaroxaban-naïve) adult patients (who may or may not be antithrombotic therapy naïve) for prevention of stroke and systemic embolism in adult patients with non-valvular AF, treatment of DVT and PE, and prevention of recurrent DVT and PE in adult patients requiring anticoagulationa | Observational, population-based, single-exposure cohort design Two waves of data collection (at baseline and 12 weeks post-index date) Additional follow-up with GP for patients discharged within the 12-week observation period Warfarin standard care used in referent cohort | All clinical practice specialities requiring anticoagulation in secondary care; patients recruited over 2 years from September 2013 Per-protocol sample size ( | Accessible target patient population was treated by specialist HCPs in anticoagulation Sampling supported by CRN specialist groups | Contextual cohort of patients receiving alternative anticoagulant therapy will inform on the adoption of rivaroxaban into clinical practice and variation in determinants of treatment choices; case definition of haemorrhagic outcomes is according to ISTH criteria [ |
AF atrial fibrillation, CHMP Committee for Medicinal Products for Human Use, CRN Clinical Research Network, DVT deep vein thrombosis, ENCEPP European Network of Centres for Pharmacoepidemiology and Pharmacovigilance, HCP health care professional, IR immediate release, ISTH International Society on Thrombosis and Haemostasis, MHRN Mental Health Research Network, PASS post-authorization safety studies, PE pulmonary embolism, RMP risk management plan, XL prolonged-release
aRivaroxaban is now also indicated for secondary prevention following an acute coronary syndrome in combination with aspirin alone or with aspirin plus clopidogrel or ticlopidine
Evaluation of the Specialist Cohort Event Monitoring (SCEM) design: strengths and limitations
| Limitations | PASS requirement affected | SCEM design features | Strengths | Distinguishing attributes for PASS |
|---|---|---|---|---|
| Selection bias from incomplete coverage, sampling process and non-response | Representativeness | Open label in secondary care setting Minimal exclusion criteria | Study off-label use Identify at-risk groups | Unique system that systematically collects good-quality information at a national scale on hospital initiation, as well as early complications and cessation, of treatment Responsive design; study fieldwork activities maintain and enhance engagement of specialist HCPs |
| Depletion of susceptibles—loss of sub-groups of high risk patients during follow-up | New-user/inception cohort | Targeted data collection to characterize the new-user study population Exposure data collected from dispensed prescription charts | Mitigates confounding by disease severity and immortal time bias, which can result in underestimation of risk of early-onset events | Indication for use reported from medical records and exposure from prescription chart; no assumptions made on surrogate markers Consent obtained to contact the GP for censored patients |
| Misclassification and underreporting | Safety outcomes | Use of well-defined case definitions based on acceptable agreed clinical standards | Expertise of the specialist provides more accurate information (through original medical records review) than that provided from hospital episode/ discharge statistics or free-text review of hospital letters sent to GPs | Can address specific regulatory questions in the context of the RMP for the product |
| Confounding and effect modification | Adjustment for measured confounders in statistical analysis | Relevant data on prognostic and potential confounding factors can be collected as recorded in medical charts before treatment was started Rigorous data quality review of returned questionnaires | Deeper level of granularity of relevant variables from secondary care medical records | Improved quality of information on important confounding variables relevant to the targeted outcomes and population of the study GP records may suffer from significant proportions of missing data that may be relevant for the study but not of clinical relevance |
GP primary care physician, HCP health care professional, PASS post-authorization safety studies, RMP risk management plan
| Specialist Cohort Event Monitoring (SCEM) addresses an existing need for safety surveillance of new medicines initiated in the hospital (secondary care) setting. |
| The method can provide insight into the adoption of a new product into clinical practice with inclusion of comparator cohorts receiving standard care, if desired. |
| SCEM can be applied to study medicines irrespective of therapeutic class and has already been incorporated into the risk management plans of some recently marketed products. |