Efficacy and safety of deferasirox at low and high iron burdens: results from the EPIC magnetic resonance imaging substudy

The effect of deferasirox dosing tailored for iron burden and iron loading based on liver iron concentration (LIC) was assessed over 1 year in less versus more heavily iron-overloaded patients in a substudy of the Evaluation of Patients' Iron Chelation with ExjadeA (R). Deferasirox starting dose was 10-30 mg/kg/day, depending on blood transfusion frequency, with recommended dose adjustments every 3 months. Therapeutic goals were LIC maintenance or reduction in patients with baseline LIC < 7 or a parts per thousand yen7 mg Fe/g dry weight (dw), respectively. Changes in LIC (R2-magnetic resonance imaging) and serum ferritin after 1 year were assessed. Adverse events (AEs) and laboratory parameters were monitored throughout. Of 374 patients, 71 and 303 had baseline LIC < 7 and a parts per thousand yen7 mg Fe/g dw, respectively; mean deferasirox doses were 20.7 and 27.1 mg/kg/day (overall average time to dose increase, 24 weeks). At 1 year, mean LIC and median serum ferritin levels were maintained in the low-iron cohort (-0.02 A +/- 2.4 mg Fe/g dw, -57 ng/mL; P = not significant) and significantly decreased in the high-iron cohort (-6.1 A +/- 9.1 mg Fe/g dw, -830 ng/mL; P < 0.0001). Drug-related gastrointestinal AEs, mostly mild to moderate, were more frequently reported in the < 7 versus a parts per thousand yen7 mg Fe/g dw cohort (39.4 versus 20.8 %; P = 0.001) and were not confounded by diagnosis, dosing, ethnicity, or hepatitis B and/or C history. Reported serum creatinine increases did not increase in low- versus high-iron cohort patients. Deferasirox doses of 20 mg/kg/day maintained LIC < 7 mg Fe/g dw and doses of 30 mg/kg/day were required for net iron reduction in the high-iron cohort, with clinically manageable safety profiles. The higher incidence of gastrointestinal AEs at lower iron burdens requires further investigation

Role of the factor VIII-binding capacity of endogenous von Willebrand factor on the development of factor VIII inhibitors in patients with severe hemophilia A

International audienc

PET/CT Imaging of c-Myc Transgenic Mice Identifies the Genotoxic N-Nitroso-Diethylamine as Carcinogen in a Short-Term Cancer Bioassay

Background: More than 100,000 chemicals are in use but have not been tested for their safety. To overcome limitations in the cancer bioassay several alternative testing strategies are explored. The inability to monitor non-invasively onset and progression of disease limits, however, the value of current testing strategies. Here, we report the application of in vivo imaging to a c-Myc transgenic mouse model of liver cancer for the development of a short-term cancer bioassay. Methodology/Principal Findings: mCT and 18 F-FDG mPET were used to detect and quantify tumor lesions after treatment with the genotoxic carcinogen NDEA, the tumor promoting agent BHT or the hepatotoxin paracetamol. Tumor growth was investigated between the ages of 4 to 8.5 months and contrast-enhanced mCT imaging detected liver lesions as well as metastatic spread with high sensitivity and accuracy as confirmed by histopathology. Significant differences in the onset of tumor growth, tumor load and glucose metabolism were observed when the NDEA treatment group was compared with any of the other treatment groups. NDEA treatment of c-Myc transgenic mice significantly accelerated tumor growth and caused metastatic spread of HCC in to lung but this treatment also induced primary lung cancer growth. In contrast, BHT and paracetamol did not promote hepatocarcinogenesis. Conclusions/Significance: The present study evidences the accuracy of in vivo imaging in defining tumor growth, tumor load, lesion number and metastatic spread. Consequently, the application of in vivo imaging techniques to transgeni

Timing and severity of inhibitor development in recombinant versus plasma-derived factor VIII concentrates: a SIPPET analysis

Essentials Recombinant factor VIII (rFVIII) was contrasted with plasma-derived FVIII (pdFVIII). In previously untreated patients with hemophilia A, rFVIII led to more inhibitors than pdFVIII. Inhibitors with rFVIII developed earlier, and the peak rate was higher than with pdFVIII. Inhibitors with rFVIII were more severe (higher titre) than with pdFVIII. Summary: Background The development of neutralizing antibodies (inhibitors) against factor VIII (FVIII) is the most severe complication in the early phases of treatment of severe hemophilia A. Recently, a randomized trial, the Survey of Inhibitors in Plasma-Product Exposed Toddlers (SIPPET) demonstrated a 2-fold higher risk of inhibitor development in children treated with recombinant FVIII (rFVIII) products than with plasma-derived FVIII (pdFVIII) during the first 50 exposure days (EDs). Objective/Methods In this post-hoc SIPPET analysis we evaluated the rate of inhibitor incidence over time by every 5 EDs (from 0 to 50 EDs) in patients treated with different classes of FVIII product, made possible by a frequent testing regime. Results The highest rate of inhibitor development occurred in the first 10 EDs, with a large contrast between rFVIII and pdFVIII during the first 5 EDs: hazard ratio 3.14 (95% confidence interval [CI], 1.01\ue2\u80\u939.74) for all inhibitors and 4.19 (95% CI, 1.18\ue2\u80\u9314.8) for high-titer inhibitors. For patients treated with pdFVIII, the peak of inhibitor development occurred later (6\ue2\u80\u9310 EDs) and lasted for a shorter time. Conclusion These results emphasize the high immunologic vulnerability of patients during the earliest exposure to FVIII concentrates, with the strongest response to recombinant FVIII products

Deviating from safety guidelines during deferiprone therapy in clinical practice may not be associated with higher risk of agranulocytosis

PubMedID: 24376176Background: A risk associated with the iron chelator deferiprone is the development of neutropenia or agranulocytosis. Accordingly, the product label recommends weekly blood monitoring and immediate interruption of treatment upon detection of an absolute neutrophil count (ANC) &lt;1.5×109/L, out of concern that continued therapy might lead to a more severe drop. However, it is uncertain how these recommendations are followed under real-life conditions and, if they are not followed, whether continuation of therapy results in increased incidence of agranulocytosis. Procedure: This non-interventional surveillance program assessed the monitoring of deferiprone therapy in clinical practice. A total of 294 patients with transfusion-dependent anemias received deferiprone, as monotherapy or with another chelator, for up to 1 year. The participating physicians were not given any instructions about treatment and monitoring beyond being referred to the information in the package insert. Results: ANC monitoring was conducted at an average interval of 5±4 weeks, and deferiprone was not always interrupted upon detection of neutropenia. One patient (0.3%) experienced agranulocytosis, and nine others (3%) experienced a total of 11 episodes of neutropenia. All neutropenia episodes resolved; median time to resolution was similar whether or not treatment was interrupted; and no case of neutropenia progressed to agranulocytosis. Conclusions: These data indicate that less frequent ANC monitoring and continuation of deferiprone therapy during neutropenia are not associated with prolonged neutropenia or with progression to agranulocytosis. © 2014 Wiley Periodicals, Inc