Adverse Event Reporting
The activity that is most commonly associated with Pharmacovigilance (PV), and which consumes a significant amount of resources for drug regulatory authorities (or similar government agencies) and drug safety departments in pharmaceutical companies, is that of adverse event reporting. Adverse event (AE) reporting involves the receipt, triage, data entering, assessment, distribution, reporting (if appropriate), and archiving of AE data and documentation. The source of AE reports may include: spontaneous reports from healthcare professionals or patients (or other intermediaries); solicited reports from patient support programs; reports from clinical or post-marketing studies; reports from literature sources; reports from the media (including social media and websites); and reports reported to drug regulatory authorities themselves. For pharmaceutical companies, AE reporting is a regulatory requirement in most countries. AE reporting also provides data to these companies and drug regulatory authorities that play a key role in assessing the risk-benefit profile of a given drug. The following are several facets of AE reporting:
The “4 Elements” of an AE case
One of the fundamental principles of adverse event reporting is the determination of what constitutes an adverse event case. During the triage phase of a potential adverse event report, the triager must determine if the “four elements” of an AE case are present:
(1) an identifiable patient,
(2) an identifiable reporter,
(3) a suspect drug, and
(4) an adverse event.
If one or more of these four elements is missing, the case is not a valid AE report. Although there are no exceptions to this rule there may be circumstances that may require a judgment call. For example, the term “identifiable” may not always be clear-cut. If a physician reports that he/she has a patient X taking drug Y who experienced Z (an AE), but refuses to provide any specifics about patient X, the report is still a valid case even though the patient is not specifically identified. This is because the reporter has first-hand information about the patient and is identifiable (i.e. a real person) to the physician. Identifiability is important so as not only to prevent duplicate reporting of the same case, but also to permit follow-up for additional information.
The concept of identifiability also applies to the other three elements. Although uncommon, it is not unheard of for fictitious adverse event “cases” to be reported to a company by an anonymous individual (or on behalf of an anonymous patient, disgruntled employee, or former employee) trying to damage the company’s reputation or a company’s product. In these and all other situations, the source of the report should be ascertained (if possible). But anonymous reporting is also important, as whistle blower protection is not granted in all countries. In general, the drug must also be specifically named. Note that in different countries and regions of the world, drugs are sold under various tradenames. In addition, there are a large number of generics which may be mistaken for the tradeproduct. Finally, there is the problem of counterfeit drugs producing adverse events. If at all possible, it is best to try to obtain the sample which induced the adverse event, and send it to either the EMA, FDA or other government agency responsible for investigating AE reports.
If a reporter can’t recall the name of the drug they were taking when they experienced an adverse event, this would not be a valid case. This concept also applies to adverse events. If a patient states that they experienced “symptoms”, but cannot be more specific, such a report might technically be considered valid, but will be of very limited value to the pharmacovigilance department of the company or to drug regulatory authorities.
Coding of Adverse Events
Adverse event coding is the process by which information from an AE reporter, called the “verbatim”, is coded using standardized terminology from a medical coding dictionary, such as MedDRA (the most commonly used medical coding dictionary). The purpose of medical coding is to convert adverse event information into terminology that can be readily identified and analyzed. For instance, Patient 1 may report that they had experienced “a very bad headache that felt like their head was being hit by a hammer” [Verbatim 1] when taking Drug X. Or, Patient 2 may report that they had experienced a “slight, throbbing headache that occurred daily at about two in the afternoon” [Verbatim 2] while taking Drug Y. Neither Verbatim 1 nor Verbatim 2 will exactly match a code in the MedDRA coding dictionary. However, both quotes describe different manifestations of a headache. As a result, in this example both quotes would be coded as PT Headache (PT = Preferred Term in MedDRA).
Although somewhat intuitive, there are a set of criteria within pharmacovigilance that are used to distinguish a serious adverse event from a non-serious one. An adverse event is considered serious if it meets one or more of the following criteria:
results in death, or is life-threatening;
requires inpatient hospitalization or prolongation of existing hospitalization;
results in persistent or significant disability or incapacity;
results in a congenital anomaly (birth defect); or is otherwise
“medically significant” —i.e., that it does not meet preceding criteria, but is considered serious because treatment/intervention would be required to prevent one of the preceding criteria.
Aside from death, each of these categories is subject to some interpretation. Life-threatening, as it used in the drug safety world, specifically refers to an adverse event that places the patient at an immediate risk of death, such as cardiac or respiratory arrest. By this definition, events such as myocardial infarction, which would be hypothetically life-threatening, would not be considered life-threatening unless the patient went into cardiac arrest following the MI. Defining what constitutes hospitalization can be problematic as well. Although typically straightforward, it’s possible for a hospitalization to occur even if the events being treated are not serious. By the same token, serious events may be treated without hospitalization, such as the treatment of anaphylaxis may be successfully performed with epinephrine. Significant disability and incapacity, as a concept, is also subject to debate. Whereas permanent disability following a stroke, would no doubt be serious, would “complete blindness for 30 seconds” be considered “significant disability”? For birth defects, the seriousness of the event is usually not in dispute so much as the attribution of the event to the drug. And, finally, medically significant events is a category that includes events that may be always serious, or sometimes serious, but will not fulfill any of the other criteria. Events such as cancer might always be considered serious, whereas liver disease, depending on its CTCAE (Common Terminology Criteria for Adverse Events) grade—Grades 1 or 2 are generally considered non-serious and Grades 3-5 serious—may be considered non-serious.
This refers to ICSRs that involve a serious and unlabelled event (an event not described in the drug’s labeling) that is considered related to the use of the drug. (Spontaneous reports are typically considered to have a positive causality, whereas a clinical trial case will typically be assessed for causality by the clinical trial investigator and/or the license holder.) In most countries, the timeframe for reporting expedited cases from the time a drug company receives notification (referred to as “Day 0”) of such a case is 15 calendar days. Within clinical trials such a cases is referred to as a SUSAR (a Suspected Unexpected Serious Adverse Reaction). If the SUSAR involves an event that is life-threatening or fatal, it may be subject to a 7-day “clock”. Cases that do not involve a serious, unlabelled event may be subject to non-expedited or periodic reporting.
Clinical Trial Reporting
Also known as SAE (Serious Adverse Event) Reporting from clinical trials, safety information from clinical studies is used to establish a drug’s safety profile in humans and is a key component that drug regulatory authorities consider in the decision-making as to whether to grant or deny market authorization (market approval) for a drug. SAE reporting occurs as a result of study patients (subjects) who experience serious adverse events during the conducting of clinical trials. (Non-serious adverse events are also captured separately.) SAE information, which may also include relevant information from the patient’s medical background, are reviewed and assessed for causality by the study investigator. This information is forwarded to a sponsoring entity (typically a pharmaceutical company) that is responsible for the reporting of this information, as appropriate, to drug regulatory authorities.
Spontaneous reporting is the core data-generating system of international pharmacovigilance, relying on healthcare professionals (and in some countries consumers) to identify and report any adverse events to their national pharmacovigilance center, health authority (such as EMA or FDA), or to the drug manufacturer itself. Spontaneous reports are, by definition, submitted voluntarily although under certain circumstances these reports may be encouraged, or “stimulated”, by media reports or articles published in medical or scientific publications, or by product lawsuits. In many parts of the world adverse event reports are submitted electronically using a defined message standard.
One of the major weaknesses of spontaneous reporting is that of under-reporting, where, unlike in clinical trials, less than 100% of those adverse events occurring are reported. Further complicating the assessment of adverse events, AE reporting behavior varies greatly between countries and in relation to the seriousness of the events, but in general probably less than 10% (some studies suggest less than 5%) of all adverse events that occur are actually reported. The rule-of-thumb is that on a scale of 0 to 10, with 0 being least likely to be reported and 10 being the most likely to be reported, an uncomplicated non-serious event such as a mild headache will be closer to a “0” on this scale, whereas a life-threatening or fatal event will be closer to a “10” in terms of its likelihood of being reported. In view of this, medical personnel may not always see AE reporting as a priority, especially if the symptoms are not serious. And even if the symptoms are serious, the symptoms may not be recognized as a possible side effect of a particular drug or combination thereof. In addition, medical personnel may not feel compelled to report events that are viewed as expected. This is why reports from patients themselves are of high value. The confirmation of these events by a healthcare professional is typically considered to increase the value of these reports. Hence it is important not only for the patient to report the AE to his health care provider (who may neglect to report the AE), but also report the AE to both the biopharmaceutical company and the FDA, EMA, … This is especially important when one has obtained one’s pharmaceutical from a compounding pharmacy.
As such, spontaneous reports are a crucial element in the worldwide enterprise of pharmacovigilance and form the core of the World Health Organization Database, which includes around 4.6 million reports (January 2009), growing annually by about 250,000.
Aggregate, or periodic reporting plays a key role in the safety assessment of drugs. Aggregate reporting involves the compilation of safety data for a drug over a prolonged period of time (months or years), as opposed to single-case reporting which, by definition, involves only individual AE reports. The advantage of aggregate reporting is that it provides a broader view of the safety profile of a drug. Worldwide, the most important aggregate report is the Periodic Safety Update Report (PSUR). This is a document that is submitted to drug regulatory agencies in Europe, the US and Japan (ICH countries), as well as other countries around the world. The PSUR was updated in 2012 and is now referred to in many countries as the Periodic Benefit Risk Evaluation report (PBRER). As the title suggests, the PBRER’s focus is on the benefit-risk profile of the drug, which includes a review of relevant safety data compiled for a drug product since its development.
Other reporting methods
Some countries legally oblige spontaneous reporting by physicians. In most countries, manufacturers are required to submit, through its Qualified Person for Pharmacovigilance (QPPV), all of the reports they receive from healthcare providers to the national authority. Others have intensive, focused programmes concentrating on new drugs, or on controversial drugs, or on the prescribing habits of groups of doctors, or involving pharmacists in reporting. All of these generate potentially useful information. Such intensive schemes, however, tend to be the exception.