Karen MacDonald
University of Pennsylvania
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Featured researches published by Karen MacDonald.
Blood | 2009
Lucien Noens; Marie Anne Van Lierde; Robrecht De Bock; Gregor Verhoef; Pierre Zachee; Zwi N. Berneman; Philippe Martiat; Philippe Mineur; Koen Van Eygen; Karen MacDonald; Sabina De Geest; Tara Albrecht; Ivo Abraham
Imatinib mesylate (imatinib) has been shown to be highly efficacious in the treatment of chronic myeloid leukemia (CML). Continuous and adequate dosing is essential for optimal outcomes and with imatinib treatment possibly being lifelong, patient adherence is critical. The ADAGIO (Adherence Assessment with Glivec: Indicators and Outcomes) study aimed to assess prospectively over a 90-day period the prevalence of imatinib nonadherence in patients with CML; to develop a multivariate canonical correlation model of how various determinants may be associated with various measures of nonadherence; and to examine whether treatment response is associated with adherence levels. A total of 202 patients were recruited from 34 centers in Belgium, of whom 169 were evaluable. One-third of patients were considered to be nonadherent. Only 14.2% of patients were perfectly adherent with 100% of prescribed imatinib taken. On average, patients with suboptimal response had significantly higher mean percentages of imatinib not taken (23.2%, standard deviation [SD] = 23.8) than did those with optimal response (7.3%, SD = 19.3, P = .005; percentages calculated as proportions x 100). Nonadherence is more prevalent than patients, physicians, and family members believe it is, and therefore should be assessed routinely. It is associated with poorer response to imatinib. Several determinants may serve as alert signals, many of which are clinically modifiable.
Respiratory Medicine | 2009
Guy Brusselle; Alain Michils; Renaud Louis; Lieven Dupont; B. Van de Maele; A. Delobbe; C. Pilette; Christopher S. Lee; Sandra Gurdain; Stefaan Vancayzeele; P. Lecomte; Christine Hermans; Karen MacDonald; MinKyoung Song; Ivo Abraham
OBJECTIVE To evaluate the 16- and 52-week effectiveness of add-on omalizumab treatment under real-life heterogeneity in patients, settings, and physicians in an open-label, multicenter, pharmaco-epidemiologic study of patients with severe persistent allergic asthma in Belgium. METHODS Effectiveness outcomes included improvement in 2005 global initiative for asthma (GINA) classification, physician-rated global evaluation of treatment effectiveness (GETE), quality of life (Juniper asthma-related quality of life (AQLQ) and European quality of life questionnaire 5 dimensions (EQ-5D)), and severe asthma exacerbations. Patients studied included both intent-to-treat and per-protocol populations. RESULTS The sample (n=158) had a mean age of 48.17+/-17.18 years, and a slight majority were female (53.8%). Despite being treated with high-dose inhaled corticosteroids and long-acting beta2-agonists, all patients experienced frequent symptoms and had exacerbations in the past year. At 16 weeks, >82% had good/excellent GETE (P values <0.001), >82% had an improvement in total AQLQ scores of > or =0.5 points (P<0.001), and >91% were severe exacerbation-free (P<0.001). At 52 weeks, >72% had a good/excellent GETE rating (P<0.001), >84% had improvements in total AQLQ score of > or =0.5 points (P<0.001), >56% had minimally important improvements in EQ-5D utility scores (P=0.012), and >65% were severe exacerbation-free (P<0.001). Significant reductions in healthcare utilization compared to the one year prior to treatment were noted. CONCLUSION The PERSIST study shows better physician-rated effectiveness, greater improvements in quality of life, greater reductions in exacerbation rates, and greater reductions in healthcare utilization than previously reported in efficacy studies. Under real-life conditions, omalizumab is effective as add-on therapy in the treatment of patients with persistent severe allergic asthma.
European Journal of Cancer | 2009
Heinz Ludwig; Matti Aapro; Carsten Bokemeyer; Karen MacDonald; Pierre Soubeyran; Matthew Turner; Tara Albrecht; Ivo Abraham
OBJECTIVES To examine anaemia management in cancer patients treated with erythropoiesis-stimulating agents (ESAs) in Europe. METHODS Retrospective pharmacoepidemiologic study of 2192 patients from 307 centres. Minimum of 3 visits over 8-10 weeks with ESA treatment initiated at visit 1. RESULTS Most patients were treated per guidelines, except for low iron supplementation rates. Mean Hb rose from 9.54+/-0.95 g/dl to 10.88+/-1.49 g/dl at visit 3, without concomitant rise in WHO/ECOG score. Response rates were 65.0% (Hb increase (upward arrow) > or = 1 g/dl); 54.3% (Hb increase (upward arrow) > or = 1 g/dl in 8 weeks); 38.9% (haematopoietic response); 33.7% (Hb increase (upward arrow) > or = 2 g/dl) and 18.8% (Hb between 12.0 and 12.9 g/dl) CONCLUSIONS Treatment patterns were guideline congruent, except for (intravenous) iron supplementation. Hb increased by 1.34 g/dl. A net erythropoiesis boost of Hb > or =1 g/dl is attainable in two-thirds of patients and should be condensed to 8 weeks on an individual patient basis. Anaemia management in Europe has improved significantly. The general effectiveness and relative safety of judicious ESA treatment are evident.
Allergy | 2016
Ivo Abraham; A. Alhossan; Christopher S. Lee; H. Kutbi; Karen MacDonald
We reviewed 24 ‘real‐life’ effectiveness studies of omalizumab in the treatment of severe allergic asthma that included 4117 unique patients from 32 countries with significant heterogeneity in patients, clinicians and settings. The evidence underscores the short‐ and long‐term benefit of anti‐IgE therapy in terms of the following: improving lung function; achieving asthma control and reducing symptomatology, severe exacerbations and associated work/school days lost; reducing healthcare resource utilizations, in particular hospitalizations, hospital lengths of stay and accident specialist or emergency department visits; reducing or discontinuing other asthma medications; and improving quality of life – thus confirming, complementing and extending evidence from randomized trials. Thus, omalizumab therapy is associated with signal improvements across the full objective and subjective burden of illness chain of severe allergic asthma. Benefits of omalizumab may extend up to 2–4 years, and the majority of omalizumab‐treated patients may benefit for many years. Omalizumab has positive short‐ and long‐term safety profiles similar to what is known from randomized clinical trials. Initiated patients should be monitored for treatment response at 16 weeks. Those showing positive response at that time are highly likely to show sustained treatment response and benefit in terms of clinical, quality of life and health resource utilization outcomes.
Leukemia Research | 2014
Michel Delforge; Dominik Selleslag; Yves Beguin; Agnès Triffet; Philippe Mineur; Koen Theunissen; Carlos Graux; Fabienne Trullemans; Dominique Boulet; Koen Van Eygen; Lucien Noens; Jan Lemmens; Pascal Pierre; Randal D'hondt; Augustin Ferrant; Dries Deeren; Ann Van de Velde; Wim Wynendaele; Marc André; Robrecht De Bock; André Efira; Dimitri A. Breems; Anne Deweweire; Kurt Geldhof; Wim Pluymers; Amanda R. Harrington; Karen MacDonald; Ivo Abraham; Christophe Ravoet
BACKGROUND Most patients with myelodysplastic syndromes (MDS) require transfusions at the risk of iron overload and associated organ damage, and death. Emerging evidence indicates that iron chelation therapy (ICT) could reduce mortality and improve survival in transfusion-dependent MDS patients, especially those classified as International Prognostic Scoring System (IPSS) Low or Intermediate-1 (Low/Int-1). METHODS Follow-up of a retrospective study. Sample included 127 Low/Int-1 MDS patients from 28 centers in Belgium. Statistical analysis stratified by duration (≥6 versus <6 months) and quality of chelation (adequate versus weak). RESULTS Crude chelation rate was 63% but 88% among patients with serum ferritin ≥1000 μg/L. Of the 80 chelated patients, 70% were chelated adequately mainly with deferasirox (26%) or deferasirox following deferoxamine (39%). Mortality was 70% among non-chelated, 40% among chelated, 32% among patients chelated ≥6 m, and 30% among patients chelated adequately; with a trend toward reduced cardiac mortality in chelated patients. Overall, median overall survival (OS) was 10.2 years for chelated and 3.1 years for non-chelated patients (p<0.001). For patients chelated ≥6 m or patients classified as adequately chelated, median OS was 10.5 years. Mortality increased as a function of average monthly transfusion intensity (HR=1.08, p=0.04) but was lower in patients receiving adequate chelation or chelation ≥6 m (HR=0.24, p<0.001). CONCLUSION Six or more months of adequate ICT is associated with markedly better overall survival. This suggests a possible survival benefit of ICT in transfusion-dependent patients with lower-risk MDS.
Clinical Ophthalmology | 2013
Jean-Marie Rakic; Anita Leys; Heidi Brié; Kris Denhaerynck; Christy Pacheco; Stefaan Vancayzeele; Christine Hermans; Karen MacDonald; Ivo Abraham
Introduction The aim of this study was to examine ranibizumab treatment patterns in “real-world” practice and clinical settings, as well as to assess quality of life outcomes over a 24-month period. Materials and methods This was a prospective, observational, multicenter, open-label study of 0.5 mg of ranibizumab administered intravitreally. Patients were followed over 24 ± 3 months with intermediate data points at 6 ± 2 months and 12 ± 2 months, and a limited data point at 2.5 ± 1 month that coincided with the end of the loading phase. Outcomes included visual acuity (Early Treatment Diabetic Retinopathy Study), visual function (National Eye Institute Visual Function Questionnaire-25 [NEI VFQ-25]), quality of life (Health Utilities Index Mark III [HUI3]), and safety. Results A total of 267 patients with wet age-related macular degeneration (mean ± standard deviation [SD] age = 78.5 ± 7.3 years; 62.4% were female; 34.5% with dual eye involvement; 74.9% were treatment-naïve) were treated (309 eyes were treated). The mean ± SD Early Treatment Diabetic Retinopathy Study score at baseline was 56.3 ± 14.3 letters. The mean ± SD number of injections over 24 months was 7.6 ± 4.1, including 2.5 ± 0.7 and 5.9 ± 3.6 during the loading and maintenance phases, respectively, with corresponding treatment intervals of 4.8 ± 1.4 weeks and 11.5 ± 9.5 weeks, respectively. Improvements in visual acuity over baseline were reached at 2.5 months and maintained at 6 months (both P < 0.0001). The mean visual acuity increase over baseline at 12 months was not significant (P = 0.08); the decline over baseline at 24 months statistically significant (P = 0.02). Overall, 94.3% of patients showed stable or improved disease at 6 months and 81.5% of patients showed stable or improved disease at 24 months. At 6 months, improvements over baseline were significant for VFQ-25 (P = 0.03) and HUI3 (P = 0.02), but not at 12 months and 24 months. Improvements in VFQ-25 and HUI3 were maintained at 24 months in 38% and 34% of patients, respectively. In total 78 serious adverse events were reported in 40 patients and 77 nonserious adverse events in 34 patients. Nine serious adverse events and nine nonserious adverse events in 14 patients were suspected to be related to ranibizumab treatment. Conclusion The “real-world” clinical effectiveness of ranibizumab was evidenced by the initial improvements over baseline in visual acuity and quality of life, as well as the maintenance of these outcomes at baseline levels at 24 months, and this was observed under variable treatment conditions. The findings underscore the need for individualized treatment with regular monitoring to achieve optimal vision and quality of life outcomes.
Expert Opinion on Drug Safety | 2012
Ivo Abraham; Karen MacDonald
Introduction: A “biosimilar” or “similar biological medicinal product” is a biological agent that is similar in terms of quality, safety, and efficacy to an authorized reference biological medicine. Since the expiration of the epoetin alfa patent in Europe, three agents have received marketing authorization from the European Medicines Agency: Binocrit (epoetin alfa; aka Abseamed and Epoetin Alfa Hexal), Retacrit (epoetin zeta; aka Silapo), and Eporatio (epoetin theta; aka Biopoin and Ratioepo). Areas covered: Using the EMA dossiers and journal publications, this article reviews clinical safety data for these products, with emphasis on serious/severe adverse events and a special consideration of immunogenicity, venous thromboembolism, and mortality. Expert opinion: A review of the available safety evidence shows that all three agents discussed have similar safety profiles. None were statistically higher on safety parameters to what is known about ESA as a class, when stratified by population. As with ESAs in general, immunogenicity, venous thromboembolism, and mortality are all concerns. What is known about ESAs regarding safety can be extended to biosimilar erythropoietins. Since biosimilars are unique, complex biological molecules, safety profiles may evolve from common to differentiated, once long-term product-specific safety data are available. Large-sample, long-term, observational studies of real-world practice will provide the heterogeneity and statistical power to demonstrate product-specific effectiveness and safety profiles. Statistically, out of the commercially available formulations of the three products reviewed, no single product is less or more safe.
Future Oncology | 2014
Ivo Abraham; Lucy Han; Diana Sun; Karen MacDonald; Matti Aapro
AIM We simulated the budget impact of biosimilar erythropoiesis-stimulating agent (ESA) in EU G5 countries. MATERIALS & METHODS Three models were built to estimate the number of patients who could be provided with antineoplastic therapy with rituximab, bevacizumab or trastuzumab from cost savings of biosimilar erythropoietin use in a hypothetical panel of 100,000 patients. The associated number of patients needed to convert to biosimilar ESA to provide such treatments was also calculated. RESULTS Under fixed dosing, the savings from 100% conversion were €110,592,159, translating into an additional 9770 rituximab, 3912 bevacizumab, or 3713 trastuzumab treatments. Under weight-based dosing, the savings from 100% conversion were €146,170,333, corresponding to an additional 12,913 rituximab, 5171 bevacizumab or 4908 trastuzumab treatments. The number of patients needed to convert ranged from four to 51. CONCLUSION Using biosimilar ESA for supportive cancer care yields significant savings and increases accessibility to primary antineoplastic therapy in a budget neutral way.
Critical Reviews in Oncology Hematology | 2011
Pere Gascón; Matti Aapro; Heinz Ludwig; Nadia Rosencher; Matthew Turner; MinKyoung Song; Karen MacDonald; Christopher Lee; Michael Muenzberg; Ivo Abraham
The MONITOR-GCSF study is an international, prospective, observational, pharmaco-epidemiological study to evaluate the multi-level factors and outcomes associated with the use of Zarzio(®) in the prophylaxis of febrile neutropenia in chemotherapy-treated cancer patients. Driven by a novel, integrated, multi-focal framework for post-approval observational studies, it examines determinants of response at both the patient and the physician level; integrates statistical methodologies from the social and behavioral sciences; assesses factors predictive of poor treatment response; and evaluates the congruence of treatment with EORTC guidelines and the approved label. This pan-European study will recruit at least 1000 patients from a minimum of 75 centers and follow them for maximum 6 cycles of chemotherapy. Apart from descriptive and associative procedures, statistical analysis will include variance attribution methods; hierarchical linear, logistic, and Poisson modeling; Kaplan-Meier time-to-event analysis, Mantel-Cox log-rank or generalized Wilcoxon-Breslow tests, and Cox proportional hazards modeling; and clustering and related data mining techniques.
European Journal of Cancer | 2009
Matti Aapro; Joanna Van Erps; Karen MacDonald; Pierre Soubeyran; Michael Muenzberg; Matthew Turner; Hans Warrinnier; Tara Albrecht; Ivo Abraham
PURPOSE To model the relationship between scores for practicing in congruence (CSs; 0-10) with EORTC guidelines for erythropoietic proteins (EPs) and haemoglobin (Hb) outcomes observed in the validation study of the RESPOND system. METHODS Thirty four patient pairs matched on cancer type and chemotherapy in pre- (retrospective; clinicians not using RESPOND) and post-cohorts (prospective; clinicians using RESPOND) followed over 4 months following EP treatment initiation. CSs quantify the extent that care was guideline-adherent. Linear and logistic regressions controlling for cohort examined Hb outcomes as a function of CSs. RESULTS A one-point increase in CS was associated with 0.60g/dL increase in Hb at month 4 (R(2)=0.40) and 0.56g/dL increase in Hb change from month 1-4 (R(2)=0.33). Each one-point increase in CS increased the odds of reaching Hb>or=11g/dL by 3.14 (R(2)=0.42) and Hb>or=12g/dL by 2.77 (R(2)=0.45). CONCLUSION Guideline-adherent EP treatment may improve Hb outcomes but specifically designed outcomes studies are necessary.