Decreased warfarin sensitivity among patients treated with elbasvir and grazoprevir for hepatitis C infection.

PURPOSE: We previously reported an interaction with warfarin anticoagulation when initiating treatment with direct-acting antiviral agents for hepatitis C infection. A decreased warfarin sensitivity led to subtherapeutic anticoagulation. To study this interaction further, we expanded our research to include patients treated with the combination of elbasvir and grazoprevir concurrent with warfarin anticoagulation and investigated changes in warfarin sensitivity during and after treatment. METHODS: Using electronic health records of the Veterans Health Administration, patients starting treatment with elbasvir-grazoprevir for hepatitis C infection concurrent with warfarin anticoagulation were identified. Inclusion required stable warfarin anticoagulation prior to 12 weeks of treatment with elbasvir-grazoprevir. A warfarin sensitivity index (WSI) was calculated at the start of treatment, after 12 weeks after treatment, and at the end of treatment. The primary endpoint was the difference in WSI from pre- to end-treatment. The secondary endpoint was the WSI difference from before treatment to Changes in International Normalized Ratio, warfarin doses, and time in therapeutic range were measured. RESULTS: In the final sample of 43 patients, the mean WSI decreased during treatment from 0.53 to 0.40, or 25.2%. After treatment, the mean WSI rose to 0.51. Although the mean weekly warfarin dose increased from 40.3 to 44.6 mg during treatment, the mean International Normalized Ratio decreased from 2.40 to 1.96, recovering to 2.59 after treatment. The time spent in therapeutic range decreased from 74.1% before treatment to 39.8% during treatment and back to 64.9% 12 weeks posttreatment. CONCLUSION: When elbasvir-grazoprevir was added to stable warfarin anticoagulation, warfarin sensitivity decreased significantly during treatment and returned to baseline after treatment.

H-ferritin ferroxidase induces cytoprotective pathways and inhibits microvascular stasis in transgenic sickle mice.

Hemolysis, oxidative stress, inflammation, vaso-occlusion, and organ infarction are hallmarks of sickle cell disease (SCD). We have previously shown that increases in heme oxygenase-1 (HO-1) activity detoxify heme and inhibit vaso-occlusion in transgenic mouse models of SCD. HO-1 releases Fe(2+) from heme, and the ferritin heavy chain (FHC) ferroxidase oxidizes Fe(2+) to catalytically inactive Fe(3+) inside ferritin. FHC overexpression has been shown to be cytoprotective. In this study, we hypothesized that overexpression of FHC and its ferroxidase activity will inhibit inflammation and microvascular stasis in transgenic SCD mice in response to plasma hemoglobin. We utilized a Sleeping Beauty (SB) transposase plasmid to deliver a human wild-type-ferritin heavy chain (wt-hFHC) transposable element by hydrodynamic tail vein injections into NY1DD SCD mice. Control SCD mice were infused with the same volume of lactated Ringer's solution (LRS) or a human triple missense FHC (ms-hFHC) plasmid with no ferroxidase activity. 8 weeks later, LRS-injected mice had ~40% microvascular stasis (% non-flowing venules) 1 h after infusion of stroma-free hemoglobin, while mice overexpressing wt-hFHC had only 5% stasis (p < 0.05), and ms-hFHC mice had 33% stasis suggesting vascular protection by ferroxidase active wt-hFHC. The wt-hFHC SCD mice had marked increases in splenic hFHC mRNA and hepatic hFHC protein, ferritin light chain (FLC), 5-aminolevulinic acid synthase (ALAS), heme content, ferroportin, nuclear factor erythroid 2-related factor 2 (Nrf2), and HO-1 activity and protein. There was also a decrease in hepatic activated nuclear factor-kappa B (NF-κB) phospho-p65 and vascular cell adhesion molecule-1 (VCAM-1). Inhibition of HO-1 activity with tin protoporphyrin demonstrated HO-1 was not essential for the protection by wt-hFHC. We conclude that wt-hFHC ferroxidase activity enhances cytoprotective Nrf2-regulated proteins including HO-1, thereby resulting in decreased NF-κB-activation, adhesion molecules, and microvascular stasis in transgenic SCD mice.

Arsenic trioxide with ascorbic acid and high-dose melphalan: results of a phase II randomized trial.

Arsenic trioxide (ATO) is synergistic with ascorbic acid (AA) and melphalan against myeloma both in vitro and in vivo. The aim of this randomized phase II trial was to determine the safety and efficacy of a combination of ATO, melphalan, and AA as preparative regimen in 48 patients undergoing autologous hematopoietic stem cell transplantation (ASCT) for multiple myeloma (MM). Forty-eight patients received melphalan 200 mg/m2 i.v. over 2 days and AA 1000 mg i.v. over 7 days in 3 treatment arms: no ATO (arm 1), ATO 0.15 mg/kg i.v. x 7 days (arm 2), and ATO 0.25 mg/kg i.v. x 7 days (arm 3). No dose-limiting toxicity, engraftment failure, or nonrelapse mortality (NRM) was seen in the first 100 days post-ASCT. Complete responses (CR) were seen in 12 of 48 patients (25%), with an overall response rate (ORR = CR + PR) of 85%. Median progression-free survival (PFS) was 25 months; median overall survival (OS) has not yet been reached. There was no significant difference in CR, PFS, or OS among the 3 treatment arms, and no adverse effect of ATO on melphalan pharmacokinetics. Addition of ATO + AA to high-dose melphalan is safe and well tolerated as a preparative regimen for MM.