Browsing by Subject "Pharmacovigilance"

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    Adverse drug reactions in South African patients receiving bedaquiline-containing tuberculosis treatment: an evaluation of spontaneously reported cases
    (2019-06-20) Jones, Jackie; Mudaly, Vanessa; Voget, Jacqueline; Naledi, Tracey; Maartens, Gary; Cohen, Karen
    Background Bedaquiline was recently introduced into World Health Organization (WHO)-recommended regimens for treatment of drug resistant tuberculosis. There is limited data on the long-term safety of bedaquiline. Because bedaquiline prolongs the QT interval, there are concerns regarding cardiovascular safety. The Western Cape Province in South Africa has an established pharmacovigilance programme: a targeted spontaneous reporting system which solicits reports of suspected adverse drug reactions (ADRs) in patients with HIV-1 and/or tuberculosis infection. Since 2015, bedaquiline has been included in the treatment regimens recommended for resistant tuberculosis in South Africa. We describe ADRs in patients on bedaquiline-containing tuberculosis treatment that were reported to the Western Cape Pharmacovigilance programme. Methods We reviewed reports of suspected ADRs and deaths received between March 2015 and June 2016 involving patients receiving bedaquiline-containing tuberculosis treatment. A multidisciplinary panel assessed causality, and categorised suspected ADRs using World Health Organisation-Uppsala Monitoring Centre system categories. “Confirmed ADRs” included all ADRs categorised as definite, probable or possible. Preventability was assessed using Schumock and Thornton criteria. Where a confirmed ADR occurred in a patient who died, the panel categorised the extent to which the ADR contributed to the patient’s death as follows: major contributor, contributor or non-contributor. Results Thirty-five suspected ADRs were reported in 32 patients, including 13 deaths. There were 30 confirmed ADRs, of which 23 were classified as “possible” and seven as “probable”. Bedaquiline was implicated in 22 confirmed ADRs in 22 patients. The most common confirmed ADR in patients receiving bedaquiline was QT prolongation (8 cases, 7 of which were severe). A fatal arrhythmia was suspected in 4 sudden deaths. These 4 patients were all taking bedaquiline together with other QT-prolonging drugs. There were 8 non-bedaquiline-associated ADRs, of which 7 contributed to deaths. Conclusions Confirmed ADRs in patients receiving bedaquiline reflect the known safety profile of bedaquiline. Quantifying the incidence and clinical consequences of severe QT-prolongation in patients receiving bedaquiline-containing regimens is a research priority to inform recommendations for patient monitoring in treatment programmes for drug resistant tuberculosis. Pharmacovigilance systems within tuberculosis treatment programmes should be supported and encouraged, to provide ongoing monitoring of treatment-limiting drug toxicity.
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    Determining antenatal medicine exposures in South African women: a comparison of three methods of ascertainment
    (2022-06-03) van der Hoven, Jani; Allen, Elizabeth; Cois, Annibale; de Waal, Renee; Maartens, Gary; Myer, Landon; Malaba, Thokozile; Madlala, Hlengiwe; Nyemba, Dorothy; Phelanyane, Florence; Boulle, Andrew; Mehta, Ushma; Kalk, Emma
    Background In the absence of clinical trials, data on the safety of medicine exposures in pregnancy are dependent on observational studies conducted after the agent has been licensed for use. This requires an accurate history of antenatal medicine use to determine potential risks. Medication use is commonly determined by self-report, clinician records, and electronic pharmacy data; different data sources may be more informative for different types of medication and resources may differ by setting. We compared three methods to determine antenatal medicine use (self-report, clinician records and electronic pharmacy dispensing records [EDR]) in women attending antenatal care at a primary care facility in Cape Town, South Africa in a setting with high HIV prevalence. Methods Structured, interview-administered questionnaires recorded self-reported medicine use. Data were collected from clinician records and EDR on the same participants. We determined agreement between these data sources using Cohen’s kappa and, lacking a gold standard, used Latent Class Analysis to estimate sensitivity, specificity and positive predictive value (PPV) for each data source. Results Between 55% and 89% of 967 women had any medicine use documented depending on the data source (median number of medicines/participant = 5 [IQR 3–6]). Agreement between the datasets was poor regardless of class except for antiretroviral therapy (ART; kappa 0.6–0.71). Overall, agreement was better between the EDR and self-report than with either dataset and the clinician records. Sensitivity and PPV were higher for self-report and the EDR and were similar for the two. Self-report was the best source for over-the-counter, traditional and complementary medicines; clinician records for vaccines and supplements; and EDR for chronic medicines. Conclusions Medicine use in pregnancy was common and no single data source included all the medicines used. ART was the most consistently reported across all three datasets but otherwise agreement between them was poor and dependent on class. Using a single data collection method will under-estimate medicine use in pregnancy and the choice of data source should be guided by the class of the agents being investigated.
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    How experiences become data: the process of eliciting adverse event, medical history and concomitant medication reports in antimalarial and antiretroviral interaction trials
    (BioMed Central Ltd, 2013) Allen, Elizabeth; Mushi, Adiel; Massawe, Isolide; Vestergaard, Lasse; Lemnge, Martha; Staedke, Sarah; Mehta, Ushma; Barnes, Karen; Chandler, Clare
    BACKGROUND:Accurately characterizing a drug's safety profile is essential. Trial harm and tolerability assessments rely, in part, on participants' reports of medical histories, adverse events (AEs), and concomitant medications. Optimal methods for questioning participants are unclear, but different methods giving different results can undermine meta-analyses. This study compared methods for eliciting such data and explored reasons for dissimilar participant responses. METHODS: Participants from open-label antimalarial and antiretroviral interaction trials in two distinct sites (South Africa, n=18 [all HIV positive]; Tanzania, n=80 [86% HIV positive]) were asked about ill health and treatment use by sequential use of (1) general enquiries without reference to particular conditions, body systems or treatments, (2) checklists of potential health issues and treatments, (3) in-depth interviews. Participants' experiences of illness and treatment and their reporting behaviour were explored qualitatively, as were trial clinicians' experiences with obtaining participant reports. Outcomes were the number and nature of data by questioning method, themes from qualitative analyses and a theoretical interpretation of participants' experiences. RESULTS: There was an overall cumulative increase in the number of reports from general enquiry through checklists to in-depth interview; in South Africa, an additional 12 medical histories, 21 AEs and 27 medications; in Tanzania an additional 260 medical histories, 1 AE and 11 medications. Checklists and interviews facilitated recognition of health issues and treatments, and consideration of what to report. Information was sometimes not reported because participants forgot, it was considered irrelevant or insignificant, or they feared reporting. Some medicine names were not known and answers to questions were considered inferior to blood tests for detecting ill health. South African inpatient volunteers exhibited a "trial citizenship", working to achieve researchers' goals, while Tanzanian outpatients sometimes deferred responsibility for identifying items to report to trial clinicians. CONCLUSIONS: Questioning methods and trial contexts influence the detection of adverse events, medical histories and concomitant medications. There should be further methodological work to investigate these influences and find appropriate questioning methods.
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    Protocol for a drugs exposure pregnancy registry for implementation in resource-limited settings
    (BioMed Central Ltd, 2012) Mehta, Ushma; Clerk, Christine; Allen, Elizabeth; Yore, Mackensie; Sevene, Esperanca; Singlovic, Jan; Petzold, Max; Mangiaterra, Viviana; Elefant, Elizabeth; Sullivan, Frank; Holmes, Lewis; Gomes, Melba
    BACKGROUND: The absence of robust evidence of safety of medicines in pregnancy, particularly those for major diseases provided by public health programmes in developing countries, has resulted in cautious recommendations on their use. We describe a protocol for a Pregnancy Registry adapted to resource-limited settings aimed at providing evidence on the safety of medicines in pregnancy.METHODS/DESIGN:Sentinel health facilities are chosen where women come for prenatal care and are likely to come for delivery. Staff capacity is improved to provide better care during the pregnancy, to identify visible birth defects at delivery and refer infants with major anomalies for surgical or clinical evaluation and treatment. Consenting women are enrolled at their first antenatal visit and careful medical, obstetric and drug-exposure histories taken; medical record linkage is encouraged. Enrolled women are followed up prospectively and their histories are updated at each subsequent visit. The enrolled woman is encouraged to deliver at the facility, where she and her baby can be assessed.DISCUSSION:In addition to data pooling into a common WHO database, the WHO Pregnancy Registry has three important features: First is the inclusion of pregnant women coming for antenatal care, enabling comparison of birth outcomes of women who have been exposed to a medicine with those who have not. Second is its applicability to resource-poor settings regardless of drug or disease. Third is improvement of reproductive health care during pregnancies and at delivery. Facility delivery enables better health outcomes, timely evaluation and management of the newborn, and the collection of reliable clinical data. The Registry aims to improve maternal and neonatal care and also provide much needed information on the safety of medicines in pregnancy.