Multicentre study of posaconazole delayed-release tablet serum level and association with hepatotoxicity and QTc prolongation.

Objectives: The association of posaconazole serum concentrations and toxicity is unclear. An assessment of whether levels obtained with the delayed-release tablet (DRT) formulation are correlated with abnormal liver function test (LFT) results and/or QTc prolongation was undertaken. Methods: This was a multicentre, retrospective, observational study of adult patients with cancer between 26 November 2013 and 14 November 2014. Patients were included if they received posaconazole DRT with a posaconazole level obtained between days 5 and 14. Clinical data, including demographics, hepatotoxic medications, posaconazole levels, LFTs and QTc intervals, were obtained. Association of factors with changes in LFTs and QTc prolongation was assessed using linear and logistic regression. Results: One hundred and sixty-six study patients were included. The median posaconazole level was 1250 (range 110-4220) ng/mL and the median time until level was 6 (range 5-14) days. There was a statistically significant increase in AST ( P < 0.001), ALT ( P < 0.001), alkaline phosphatase (ALK) ( P < 0.001), total bilirubin (TBILI) ( P < 0.001) and QTc ( P = 0.05) from baseline. Posaconazole levels were not associated with increases in AST [ß (SE) = -0.33 (2.2), P = 0.88], log ALT [ß (SE) = -0.02 (0.03), P = 0.63], ALK [ß (SE) = 2.2 (2.9), P = 0.46] and TBILI [ß (SE) = -0.01 (0.04), P = 0.88]. For each additional hepatotoxic medication, there was a mean change in TBILI of 0.13 mg/dL ( P = 0.02) and ALK of 7.1 U/L ( P = 0.09). No statistically significant association between posaconazole level and QTc interval prolongation was found. Conclusions: We did not identify an association between posaconazole serum concentrations and LFT elevations or QTc prolongation. However, some LFTs were found to increase with more hepatotoxic medications administered.

Effect of antifungal therapy timing on mortality in cancer patients with candidemia.

Prior studies have shown that delays in treatment are associated with increased mortality in patients with candidemia. The purpose of this study was to measure three separate time periods comprising the diagnosis and treatment of candidemia and to determine which one(s) is associated with hospital mortality. Patients with blood cultures positive for Candida spp. were identified. Subjects were excluded if no antifungal therapy was given or if there was preexisting antifungal therapy. Collected data included the time from blood culture collection to positivity (incubation period), the time from blood culture positivity to provider notification (provider notification period), and the time from provider notification to the first dose of antifungal given (antifungal initiation period). These times were assessed as predictors of inpatient mortality. A repeat analysis was done with adjustments for age, sex, race, underlying cancer, catheter removal, APACHE III score, acute renal failure, neutropenia, and non-Candida albicans species. A total of 106 episodes of candidemia were analyzed. The median incubation time was 32.1 h and was associated with mortality (univariate hazard ratio per hour, 1.025; P = 0.001). The median provider notification and antifungal initiation periods were 0.3 and 7.5 h, respectively, and were not associated with mortality. Adjusted analysis yielded similar results. For cancer patients with candidemia, the incubation period accounts for a significant amount of time, compared with the provider notification and antifungal initiation times, and is associated with in-hospital mortality. Strategies to shorten the incubation time, such as utilizing rapid molecularly based diagnostic methods, may help reduce in-hospital mortality.