Prospective Clinical, Virologic, and Immunologic Assessment of COVID-19 in Transplant Recipients.

BACKGROUND: Several studies have described the clinical features of COVID-19 in solid-organ transplant recipients. However, many have been retrospective or limited to more severe cases (hospitalized) and have not routinely included serial virological sampling (especially in outpatients) and immunologic assessment. METHODS: Transplant patients diagnosed with COVID-19 based on a respiratory sample PCR were prospectively followed up to 90 d. Patients provided consent for convalescent serum samples and serial nasopharyngeal swabs for SARS-CoV-2 antibody (antinucleoprotein and anti-RBD) and viral load, respectively. RESULTS: In the 161 SOT recipients diagnosed with COVID-19, the spectrum of disease ranged from asymptomatic infection (4.3%) to hospitalization (60.6%), supplemental oxygen requirement (43.1%), mechanical ventilation (22.7%), and death (15.6%). Increasing age (OR, 1.031; 95% CI, 1.001-1.062; P = 0.046) and ≥2 comorbid conditions (OR, 3.690; 95% CI, 1.418-9.615; P = 0.007) were associated with the need for supplemental oxygen. Allograft rejection was uncommon (3.7%) despite immunosuppression modification. Antibody response at ≥14 d postsymptoms onset was present in 90% (anti-RBD) and 76.7% (anti-NP) with waning of anti-NP titers and stability of anti-RBD over time. Median duration of nasopharyngeal positivity was 10.0 d (IQR, 5.5-18.0) and shedding beyond 30 d was observed in 6.7% of patients. The development of antibody did not have an impact on viral shedding. CONCLUSIONS: This study demonstrates the spectrum of COVID-19 illness in transplant patients. Risk factors for severe disease are identified. The majority form antibody by 2 wk with differential stability over time. Prolonged viral shedding was observed in a minority of patients. Reduction of immunosuppression was a safe strategy.

The economic impact of increased length of stay associated with surgical site infections in liver transplantation on Canadian healthcare costs.

BACKGROUND: Complications after liver transplantation cause additional healthcare costs. The objective of this study was to contrast the length of stay (LOS) costs for recipients with and without surgical site infections (SSIs). METHODS: This retrospective observational cohort study was conducted at a transplant center in Canada, between February 2011 and August 2014. The difference in the LOS costs was assessed by the Mann-Whitney U test, while multiple linear regression analysis was used to identify the variables that may have impacted on the costs. RESULTS: Two hundred and twenty-nine liver transplant recipients were enrolled. Thirty-six recipients developed SSIs (36/229, 15.7%). The median LOS costs in recipients with and without SSIs were $39,456 Canadian dollars (interquartile range $25,696- 59,722) and $31,084 Canadian dollars (interquartile range $22,712-49 610), respectively (p = .072). There was a trend that the costs were higher for those recipients with versus those without SSIs (p = .088). Transfusion of ≥ 5 units of red cells and dialysis before transplantation impacted on cost. CONCLUSION: There was a trend for higher healthcare facility costs for recipients with SSIs. Red cell transfusions and greater dialysis use before transplant were factors associated with the cost. Implementation of cost reduction strategies targeting high-cost recipients is necessary.

Therapeutic drug monitoring for triazoles: A needs assessment review and recommendations from a Canadian perspective.

Invasive fungal infections cause significant morbidity and mortality in patients with concomitant underlying immunosuppressive diseases. The recent addition of new triazoles to the antifungal armamentarium has allowed for extended-spectrum activity and flexibility of administration. Over the years, clinical use has raised concerns about the degree of drug exposure following standard approved drug dosing, questioning the need for therapeutic drug monitoring (TDM). Accordingly, the present guidelines focus on TDM of triazole antifungal agents. A review of the rationale for triazole TDM, the targeted patient populations and available laboratory methods, as well as practical recommendations based on current evidence from an extended literature review are provided in the present document.

Les infections fongiques invasives sont responsables d'une morbidité et d'une mortalité importantes chez les patients atteints d'une maladie immunodépressive. L'ajout des nouveaux triazoles aux traitements antifongiques a élargi le spectre d'activité et la flexibilité d'administration. Au fil des ans, leur utilisation clinique a suscité des inquiétudes quant au degré d'exposition au médicament selon une posologie approuvée standard, ce qui soulève la nécessité de la pharmacovigilance thérapeutique (PVT). Les présentes lignes directrices portent donc sur la PVT des antifongiques triazolés. Dans le présent document sont exposées une analyse de la raison d'être de la PVT des triazoles, les populations de patients ciblées et les méthodes de laboratoire offertes, de même que des recommandations pratiques fondées sur des données probantes à jour tirées d'une analyse bibliographique approfondie.

Pharmacoeconomic assessment of therapy for invasive aspergillosis.

Invasive aspergillosis (IA) is a major cause of morbidity and mortality in immunocompromised hosts. Economic expenditures prompted by this invasive fungal infection (IFI) are significant. Although, the duration and associated costs of hospitalization comprise the largest proportion of costs in large surveillance studies, the newer oral antifungal agents may impact significantly on these costs. A review of the pharmacoeconomic (PE) studies is provided focussing on primary therapy, salvage therapy, empiric therapy and prophylaxis for IA. PE evaluations have demonstrated the cost effectiveness and dominance of voriconazole for targeted primary treatment of IA compared with other available agents. Differences in the drug choice and analytic methodology of the PE analyses of empiric antifungal strategy hamper definitive conclusions about the agents employed as empiric antifungal that may be directed at suspected IA although both caspofungin and voriconazole appear to be cost effective and dominant over liposomal amphotericin B (LAmB), whereas LAmB is more costly than conventional amphotericin B. Posaconazole is the most cost-effective agent for antifungal prophylaxis against IFI and IA.

Economic evaluation of posaconazole versus standard azole therapy as prophylaxis against invasive fungal infections in patients with prolonged neutropenia in Canada.

INTRODUCTION: Posaconazole prophylaxis in high-risk neutropenic patients prevents invasive fungal infection (IFI). An economic model was used to assess the cost effectiveness of posaconazole from a Canadian health care system perspective. METHODS: A decision-analytic model was developed based on data from a randomized trial comparing posaconazole with standard azole (fluconazole or itraconazole) therapy. The model was extrapolated to a lifetime horizon using one-month Markov cycles; lifetime survival was specific to the underlying disease. Drug and treatment costs associated with IFI were estimated using published literature. The model was used to estimate total costs, IFIs avoided, life-years gained and the incremental cost-effectiveness ratio of posaconazole versus standard azole therapy, in 2007 Canadian dollars. RESULTS: Based on the clinical trial data, posaconazole was associated with fewer cases of IFI (0.05 versus 0.11; P=0.003), increased life-years (2.52 years versus 2.43 years) and slightly lower costs ($6,601 versus $7,045) per patient relative to standard azole therapy over a lifetime horizon. Higher acquisition costs for posaconazole were offset by IFI-associated inpatient costs for those prophylaxed with standard azoles. Probabilistic sensitivity analysis indicated a 59% probability that posaconazole was cost-saving versus standard azole therapy and a 96% probability that the incremental cost-effectiveness ratio for posaconazole was at or below the $50,000 per life-year saved threshold. DISCUSSION: In Canada, posaconazole appears to be cost-saving relative to standard azole therapy in IFI prevention among high-risk neutropenic patients.

INTRODUCTION: La prophylaxie au posaconazole chez les patients neutropéniques à haut risque prévient l'infection fongique invasive (IFI). Les chercheurs ont utilisé un modèle économique pour évaluer le rapport coût-efficacité du posaconazole dans un système de santé canadien. MÉTHODOLOGIE: Les chercheurs ont mis au point un modèle de décision analytique fondé sur des données tirées d'un essai aléatoire comparant le posaconazole à un traitement standard à l'azole (fluconazole ou itraconazole). Ils ont extrapolé le modèle à l'horizon d'une vie au moyen de modèles de Markov sur un mois. La survie longitudinale dépendait de la maladie sous-jacente. Ils ont estimé les coûts des médicaments et des traitements associés à l'IFI d'après des publications scientifiques et utilisé le modèle pour estimer les coûts totaux, les IFI évitées, les années de vie gagnées et le rapport coût-efficacité incrémentiel (RCEI) du posaconazole par rapport à une thérapie standard à l'azole, en dollars canadiens de 2007. RÉSULTATS: D'après les données d'essai clinique, le posaconazole s'associait à un moins grand nombre de cas d'IFI (0,05 par rapport à 0,11; P=0,003), à l'augmentation des années de vie (2,52 ans par rapport à 2,43 ans) et à des coûts légèrement moins élevés (6 601 $ par rapport à 7 045 $) par patient par rapport à la thérapie standard à l'azole sur l'horizon d'une vie. Les coûts d'acquisition plus élevés du posaconazole étaient contrebalancés par les coûts d'hospitalisation des patients en raison d'une IFI qui recevaient une prophylaxie standard aux azoles. D'après l'analyse de sensibilité probabiliste, il y avait 59 % de probabilité que le posaconazole soit plus économique que la thérapie standard à l'azole et 96 % de probabilité que le RCEI du posaconazole corresponde ou soit inférieur au seuil de 50 000 $ par année de vie épargnée. EXPOSÉ: Au Canada, le posaconazole semble être économique par rapport à la thérapie standard à l'azole pour prévenir l'IFI chez les patients neutropéniques à haut risque.

Resource utilization and cost of treatment with anidulafungin or fluconazole for candidaemia and other forms of invasive candidiasis: focus on critically ill patients.

BACKGROUND: Candidaemia and other forms of invasive candidiasis (C/IC) are serious and costly events for hospitalized patients, particularly those in the ICU. Both fluconazole and the echinocandins are recommended as first-line therapy for C/IC. Resource use and cost considerations are important in selecting appropriate treatment but little information is available on the economic implications of using echinocandins in this setting. OBJECTIVE: To compare resource utilization and treatment costs (in $US) associated with the echinocandin anidulafungin (200 mg intravenously on day 1, then 100 mg intravenously daily) versus those of fluconazole (800 mg intravenously on day 1, then 400 mg intravenously daily) as first-line treatment for C/IC. METHODS: Available charts from patients enrolled in a recent clinical trial comparing anidulafungin and fluconazole for C/IC were reviewed. Patients who were in the ICU at study entry were identified, and the following data, collected during the 13-week study period, were compared between treatment groups: global response at end of study treatment, number of days patients survived after hospital discharge ('hospital-free' days), hospital resource use, and C/IC-related costs (year 2008 values) to a US hospital payer. These comparisons were also conducted for all non-ICU hospitalized patients, and for survivors in both study populations. Sensitivity analyses explored the cost impact of variability in the hospitalization costs between ICUs and non-ICU wards and of reduced duration intravenous therapy. Statistical comparisons between the two treatment groups were conducted for clinical outcomes, resource use and cost measures, using regression models. All statistical comparisons were adjusted for baseline co-variates (Acute Physiology and Chronic Health Evaluation [APACHE] II score, absolute neutrophil count and catheter removal status). RESULTS: For ICU patients with C/IC (n = 63), global response was significantly higher for anidulafungin than fluconazole (68.6% vs 42.9%; p = 0.03). ICU patients treated with anidulafungin had an average of 13.9 more hospital-free days (18.2 vs 4.3 days; p = 0.04) than those treated with fluconazole. After adjustment for co-variates, although lower costs were observed for anidulafungin vs fluconazole in ICU patients and in ICU patients who survived, no statistical differences were found. For all hospitalized patients (n = 159), global response was also higher for anidulafungin (78.3% vs 60.5%; p < 0.01). There was no difference in average length of hospitalization (29.6 days) or hospital-free days. After adjustment for co-variates, anidulafungin treatment resulted in an incremental C/IC-related cost of $US2680 (p = 0.73). For hospitalized patients who survived (anidulafungin 81.9%, fluconazole 69.7%), anidulafungin treatment was associated with an incremental cost of $US231 (p = 0.98). CONCLUSION: Anidulafungin as first-line treatment of C/IC appears to be of particular benefit to ICU patients, improving clinical outcomes and possibly decreasing costs, driven by reduced ICU and hospital stay, when compared with fluconazole. Anidulafungin also yielded significantly improved treatment outcomes in the general inpatient population, with total costs similar to fluconazole.

Management of invasive candidiasis and candidemia in adult non-neutropenic intensive care unit patients: Part I. Epidemiology and diagnosis.

BACKGROUND: Invasive candidiasis and candidemia are frequently encountered in the nosocomial setting, particularly in the intensive care unit (ICU). OBJECTIVES AND METHODS: To review the current management of invasive candidiasis and candidemia in non-neutropenic adult ICU patients based on a review of the literature and a European expert panel discussion. RESULTS AND CONCLUSIONS: Candida albicans remains the most frequently isolated fungal species followed by C. glabrata. The diagnosis of invasive candidiasis involves both clinical and laboratory parameters, but neither of these are specific. One of the main features in diagnosis is the evaluation of risk factor for infection which will identify patients in need of pre-emptive or empiric treatment. Clinical scores were built from those risk factors. Among laboratory diagnosis, a positive blood culture from a normally sterile site provides positive evidence. Surrogate markers have also been proposed like 1,3 beta-D: glucan level, mannans, or PCR testing. Invasive candidiasis and candidemia is a growing concern in the ICU, apart from cases with positive blood cultures or fluid/tissue biopsy, diagnosis is neither sensitive nor specific. The diagnosis remains difficult and is usually based on the evaluation of risk factors.

Economic evaluation of voriconazole for the treatment of candidemia in Canadian adults.

BACKGROUND: Candidemia is a common cause of nosocomial bloodstream infection. When selecting therapeutic treatments for candidemia, cost-effectiveness is an important consideration. The present study assessed the cost-effectiveness of voriconazole for the treatment of candidemia. METHODS: A decision-analytical model was used for evaluating the cost-effectiveness of voriconazole compared with a regimen of conventional amphotericin B (CAB) followed by fluconazole (FLU) in the treatment of non-neutropenic patients diagnosed with candidemia in the Canadian setting, based on the Global Candidemia Study. The time frame of the model was 98 days (14 weeks). Model parameters were based primarily on clinical outcome, and resource use data collected from the clinical trial were used. Supplemental data were obtained from an independent panel of 12 Canadian experts for parameters not available from the clinical trial. Unit costs were collected from Canadian sources. The outcome variables selected in the study were the number of patients cured within 98 days, the number of patients surviving at 98 days and the number of patients avoiding toxicity. Incremental costs per outcome were calculated to compare the cost-effectiveness analyses (both probabilistic and one-way sensitivity analyses were performed). RESULTS: The cost-effectiveness analysis demonstrated a difference of $1,121 in the total average cost of treatment with voriconazole ($70,489) versus CAB/FLU ($69,368). While the costs of voriconazole exceeded the costs of CAB/FLU, these costs were almost completely offset by lower hospitalization costs. While patients in both treatment arms experienced cure rates of 41%, both the percentage of patients surviving at day 98 (64.5% versus 58.2%) and the percentage of patients avoiding toxicity (64.5% versus 52.5%) were higher in the voriconazole arm. Accounting for differences in total costs and clinical outcomes, this analysis estimated an incremental cost per patient surviving at day 98 of $17,739, and an incremental cost per patient avoiding toxicity of $9,298. In the case of cost per patient cured, voriconazole had a higher cost ($1,121) than CAB/FLU. The results of the deterministic and probabilistic sensitivity analyses indicated that the model was robust. CONCLUSIONS: Results of the decision-analytical model provided evidence to support the cost-effectiveness of voriconazole relative to a regimen of CAB/FLU in the treatment of non-neutropenic patients diagnosed with candidemia in the Canadian setting.

An economic evaluation of voriconazole versus amphotericin B for the treatment of invasive aspergillosis in Canada.

BACKGROUND: Invasive aspergillosis (IA) is a serious fungal infection that affects immunocompromised patients. The Global Comparative Aspergillosis study demonstrated that voriconazole, a new broad-spectrum triazole, had better responses and improved survival compared with conventional amphotericin B deoxycholate (CAB) and other licensed antifungal therapy (OLAT) for the treatment of definite or probable aspergillosis. OBJECTIVES: To compare costs and outcomes of voriconazole and CAB for the treatment of definite or probable aspergillosis in Canada. METHODS: A cost-consequence decision tree model was designed to reflect the treatment pathways used in clinical practice when using voriconazole or CAB as primary therapy for IA. Therapy included initial treatment with either voriconazole or CAB and then switched to an OLAT in the event of an inadequate response, severe toxicity or intolerance. The principal data source used was the Global Comparative Aspergillosis study. RESULTS: The total cost of voriconazole when compared with CAB as initial therapy for IA was $38,319 versus $42,495 per patient, respectively, representing a 9.8% cost reduction for each patient treated with voriconazole. The higher mean cost in the CAB arm was primarily due to the high proportion of patients (73.7%) who were switched to an OLAT due to severe side effects or an inadequate response. Treating with voriconazole was a dominant strategy. The number of patients that had to be treated with voriconazole instead of CAB to save one additional life was eight. CONCLUSIONS: Voriconazole as primary treatment for IA increased the chances of successful treatment, improved survival and may represent a potential cost saving strategy in Canada.