Monitoring the manufacturing and quality of medicines: a fundamental task of pharmacovigilance.

The collection and assessment of individual case safety reports (ICSRs) is important to detect unknown adverse drug reactions particularly in the first decade after approval of new chemical entities. However, regulations require that these activities are routinely undertaken for all medicinal products, including older medicines such as generic medicinal products with a well-established safety profile. For the latter, the risk management plans no longer contain important risks, considered important safety concerns, on the basis that routine pharmacovigilance activity would not allow their further characterisation. Society assumes that unexpected adverse reactions causally related to pharmacological activity are very unlikely to be detected for such well-established medicines, but important risks can still occur. For these products, a change in the safety profile which is brand or source specific and usually local in nature, associated with failures with the adequate control of quality of manufacturing or distribution are important safety issues. These may be the consequence of manufacturing and pharmacovigilance quality systems that are not fully integrated over the product life cycle (e.g. inadequate control of quality defects affecting one or multiple batches; inadequate impact assessment of change/variation of manufacturing, quality control testing, storage and distribution processes; inadequate control over the distribution channels including the introduction of counterfeit or falsified products into the supply chain). Drug safety hazards caused by the above-mentioned issues have been identified with different products and formulations, from small molecules to complex molecules such as biological products extracted from animal sources, biosimilars and advanced therapy medicinal products. The various phases of the drug manufacturing and distribution of pharmaceutical products require inputs from pharmacovigilance to assess any effects of quality-related issues and to identify proportionate risk minimisation measures that often have design implications for a medicine which requires a close link between proactive vigilance and good manufacturing practice. To illustrate our argument for closer organisational integration, some examples of drug safety hazards originating from quality, manufacturing and distribution issues are discussed. PLAIN LANGUAGE SUMMARY: Monitoring the manufacturing and quality of medicines: the fundamental task of pharmacovigilance Pharmacovigilance is the science relating to the collection, detection, assessment, monitoring, and prevention of adverse reactions with pharmaceutical products. The collection and assessment of adverse reactions are particularly important in the first decade after marketing authorisation of a drug as the information gathered in this period could help, for example, to identify complications from its use which were unknown before its commercialization. However, when it comes to medicines that have been on the market for a long time there is general acceptance that their safety profile is already well-established and unknown adverse reactions unlikely to occur. Nevertheless, even older medicines, such as generic drugs, can generate new risks. For these drugs a change in the safety profile could be the result of inadequate control of their quality, manufacturing and distribution systems. To overcome such an obstacle, it is necessary to fully integrate manufacturing and pharmacovigilance quality systems in the medicine life-cycle. This could help detect safety hazards and prevent the development of new complications which may arise due to the poor quality of a drug. Pharmacovigilance activities should indeed be included in all phases of the drugs' manufacturing and distribution process, regardless of their chemical complexity to detect quality-related matters in good time and reduce the risk of safety concerns to a minimum.

Evaluation of quantitative signal detection in EudraVigilance for orphan drugs: possible risk of false negatives.

Different strategies have been studied to allow a better characterization of the safety profile of orphan drugs soon after their approval. At the end of the development phases only few data are available because of the small number of subjects exposed to an orphan medicine for the treatment of rare or ultra-rare conditions. As a consequence, the evaluation of the safety profile is limited at the time of the first approval. In the post-marketing period, all available sources should be combined for a better understanding of the safety of orphan drugs. These sources, include outputs from large databases such as the European Medicines Agency's EudraVigilance database. Analyses of data from this source are required to be performed by marketing authorization holders (MAHs) as part of their signal management activities. In 2018, the Pharmacovigilance Risk Assessment Committee (PRAC) assessed 114 confirmed signals, 79% of which included data from EudraVigilance. MAHs have access to statistical calculations for drug-event combinations (DECs) from EudraVigilance, provided in the form of measures of disproportionality of ratios of the observed proportion of spontaneous cases for a DEC in relation to the proportion of cases that would be expected if no association existed between the drug and the event. However, such statistical summaries for orphan drugs could be misleading because of the very limited safety data available for orphan drugs (under-reporting together with low numbers of exposed patients). In addition, the applied statistical methodology in most instances is constrained by different confounding factors such as indications of specific medicines and the wide spectrum of medical conditions/diseases of patients from whom reporting of disproportionality ratios are derived (i.e. proportions of DECs for orphan drugs (ODECs) from a small patient population suffering the rare disease and the proportion of DECs in the rest of the population represented in the whole database who have been treated with other medicines for a wide range of indications, and prescribed to treat completely different medical conditions). As expected, these statistical calculations produced not only signals of disproportionate reporting (SDRs) that are false positives, but also not sensitive enough to detect certain SDRs, thus resulting in false negatives. In the context of rare/ultra-rare life-threatening diseases where new molecules have been made available on the market on the basis of their proven efficacy, but with only limited safety data at the time of approval, false negatives could be a special concern since unlikely converted in positives or becoming positives with notable delay. Subgroup analyses (using a limited dataset comprising ADRs within specific individual case safety reports (ICSRs), sorted by indication/disease relevant to the drug of interest could, at least in part, possibly reduce some of the weaknesses resulting from the abovementioned confounding factors. On the other hand it could also cause the loss of some identification of SDRs that would be captured if no database restrictions had been undertaken. Therefore, data subgroup analysis should not be selected as a preferred approach to quantitative signal detection for orphan drugs but rather evaluated as complementary possibly to confirm negatives or to further characterize detected SDRs. Some examples of false negatives originating from quantitative signal detection in EudraVigilance applied to orphan drugs are discussed in this article.

Pharmacovigilance of medicines for rare and ultrarare diseases.

The assessment of the safety of medicines for rare diseases during the development phase is often limited by the few data available from small numbers of patients. This also applies to a lesser extent during the postmarketing phase of the lifecycle of a medicine. By using all available sources of data for rare diseases drugs, and by carefully assessing these data, the most informed safety profile can be obtained. This should also allow a clear view of data that are not available at any given time point and facilitates planning of strategies to obtain data through appropriate postmarketing risk management. Although it is not always easy, there are possibilities to increase the speed by which data in the postmarketing period can be generated by better use of data from ongoing formal clinical trials, by early planning of drug or disease registries and leveraging the power of both disease patient support groups, which are often well established, and networks to facilitate international research, specifically in rare diseases. The future may offer approaches using personal medical monitoring data tools and 'big data' to further facilitate the availability of information and to determine the effectiveness and safety profiles of drugs used for rare diseases and thus allow the benefit/risk of these drugs to be optimized. These issues will be discussed here.

Drug safety evaluation of defibrotide.

INTRODUCTION: Hepatic veno-occlusive disease (VOD), also known as sinusoidal obstruction syndrome (SOS), is a potentially life-threatening complication of chemotherapeutic conditioning used in preparation for hematopoietic stem-cell transplantation (SCT). Defibrotide (DF) has been shown in Phase II and III trials to improve complete response in patients with severe VOD (sVOD). None of the articles, to date, provide a comprehensive review of the safety of DF in VOD and/or a range of other conditions. AREAS COVERED: This article reviews current clinical findings on DF, primarily in terms of safety for use in treatment and prophylaxis of VOD, and relevant safety data for its use in other diseases. The literature review was conducted using a PubMed search with the fixed term 'defibrotide' in combination with ≥ 1 of 'safety', 'veno-occlusive disease' (with and without 'treatment', 'prevention'), 'oncology', 'myeloma', 'microangiopathy', 'anti-thrombotic' and 'peripheral vascular disorder'. Related articles from the EBMT and ASH conference websites were also included. EXPERT OPINION: DF was well tolerated in majority of the studies. The safety profile of DF is largely favourable with toxicities comparable to control populations in the setting of SCT complicated by sVOD.

Dopamine is involved in the antidepressant-like effect of allopregnanolone in the forced swimming test in female rats.

Evidence from both animal and human studies suggests a role for dopamine in the therapeutic effect of antidepressant drugs. Consistently, dopamine receptor antagonists antagonize the effect of antidepressant drugs in different experimental models of depression. Neurosteroids, and in particular allopregnanolone, seem to be involved both in the pathophysiology of depression and in the mechanism of action of antidepressant drugs, and their role seems to be particularly important in the understanding of mood disturbances related to the different phases of the reproductive life in women. The aim of this study was to investigate the possible role of dopamine on the antidepressant-like effect of allopregnanolone in a model of depression. Thus, we examined (i) the behaviour of female Sprague-Dawley rats in the forced swimming test during estrus and diestrus and their response to allopregnanolone treatment (0.5, 1 and 2 mg/kg), and (ii) the effect of the dopamine D1-like and D2-like receptor antagonists SCH 23390 (0.01 and 0.025 mg/kg) and raclopride (0.05 and 0.2 mg/kg) on the antidepressant-like effect of allopregnanolone (2 mg/kg) in the same experimental model. We failed to observe differences in depressive-like behaviour between estrous phases, and allopregnanolone administration in both estrus and diestrus resulted in an antidepressant-like effect consisting in an increase of swimming behaviour. The allopregnanolone effect was unaffected by a dose of the dopamine D1-like receptor antagonist SCH 23390 displaying a marked inhibitory effect on basal activity, while it was turned into a potentiation of the depressive-like behaviour of the forced swimming condition by treatment with the higher dose of raclopride. The present results indicate an involvement of dopamine transmission in the allopregnanolone antidepressant-like effect in the forced swimming model of depression, and suggest that this effect depends mainly on stimulation of dopamine D2-like receptors.