Stephen Harnicar

Safe and effective use of rivaroxaban for treatment of cancer-associated venous thromboembolic disease: a prospective cohort study

Low-molecular weight heparin (LMWH) has been the standard of care for treatment of venous thromboembolism (VTE) in patients with cancer. Rivaroxaban was approved in 2012 for the treatment of pulmonary embolism (PE) and deep vein thrombosis (DVT), but no prior studies have been reported specifically evaluating the efficacy and safety of rivaroxaban for cancer-associated thrombosis (CAT). Under a Quality Assessment Initiative (QAI), we established a Clinical Pathway to guide rivaroxaban use for CAT and now report a validation analysis of our first 200 patients. A 200 patient cohort with CAT (PE or symptomatic, proximal DVT), whose full course of anticoagulation was with rivaroxaban, were accrued. In competing risk analysis, primary endpoints at 6 months included new or recurrent PE or symptomatic proximal lower extremity DVT, major bleeding, clinically-relevant non-major bleeding leading to discontinuation of rivaroxaban, or death. In competing risk analysis, the 6 months cumulative incidence of new or recurrent VTE was 4.4 % (95 % CI = 1.4–7.4 %), major bleeding was 2.2 % (95 % CI = 0−4.2 %) and all-cause mortality 17.6 % (95 % CI = 11.7–23.0 %). In this cohort of 200 patients with active cancer and CAT the rates of new or recurrent VTE and major bleeding were comparable to the cancer subgroup analysis from the EINSTEIN studies. The results of our Clinical Pathway provide guidance on Rivaroxaban use for treatment of CAT, and suggest that safety and efficacy is preserved, compared with past-published experience with LMWH.

Modification of vincristine dosing during concomitant azole therapy in adult acute lymphoblastic leukemia patients

Objective. Vincristine is an important component in the treatment of acute lymphoblastic leukemia (ALL) and is now the backbone of therapy in the induction and consolidation phases of this disease. Proper dosing of vincristine is required to maximize disease control while avoiding toxicity. The gastrointestinal toxicity of vincristine such as decreased peristalsis can potentially be increased if the CYP 3A4 enzyme is inhibited. This interaction may become more prevalent with increasing use of CYP 3A4 inhibitors such as the azole antifungals. Since azoles are increasingly being used for prophylaxis and treatment of fungal infections in this patient population, an assessment of vincristine dosing and toxicity is the first step to constructing guidelines for the coadministration of these agents. Methods. ALL patients !18 years of age receiving vincristine-based therapy from August 2003 through December 2007 with or without azole therapy were included. Data was collected using electronic patient medical records and the pharmacy system (RxTFC). Information was entered into a database for this retrospective study. Patients were separated into two arms; vincristine with azoles and vincristine only. Patient demographic information, chemotherapy regimen, vincristine-induced symptoms, and concurrent strong CYP 3A4 inhibitors and inducers were collected. Results. A total of 50 patients received vincristine of which 29 (58%) had concurrent azole therapy. No patients received concurrent major CYP 3A4 inhibitors and the baseline characteristics were similar between groups. Vincristine dosing modifications were more common in the azole group (58.6 vs. 23.8%; p = 0.02). The mean dose reduction of vincristine when combined with an azole was 46.5%. Symptoms of decreased peristalsis were more common in patients receiving azoles (65.5 vs. 28.6%; p = 0.019) and on average occurred after the second vincristine dose. Symptoms occurred in 50, 75, and 66.6% of patients receiving fluconazole, voriconazole, and posaconazole, respectively. Patients were more likely to have an incomplete course of vincristine when receiving azole therapy (48.3 vs. 9.5%; p = 0.004). Conclusion. Caution should be used with the coadministration of vincristine and azoles. It is recommended that institutional guidelines be developed to standardize care for patients receiving vincristine with azole therapy. Potential measures to avoid this interaction include revisiting azole prophylaxis in this patient group and being judicious in azole selection.

Intensified Mycophenolate Mofetil Dosing and Higher Mycophenolic Acid Trough Levels Reduce Severe Acute Graft-versus-Host Disease after Double-Unit Cord Blood Transplantation.

Although mycophenolate mofetil (MMF) has replaced corticosteroids as immunosuppression in cord blood transplantation (CBT), optimal MMF dosing has yet to be established. We intensified MMF dosing from every 12 to every 8 hours to augment graft-versus-host disease (GVHD) prophylaxis in double-unit cord blood transplantation (dCBT) and evaluated outcomes according to the total daily MMF dose/kg in 174 dCBT recipients (median age, 39 years; range, 1 to 71) who underwent transplantation for hematologic malignancies. Recipients of an MMF dose ≤ the median (36 mg/kg/day) had an increased day 100 grade III and IV acute GVHD (aGVHD) incidence compared with patients who received >36 mg/kg/day (24% versus 8%, P = .008). Recipients of ≤ the median dose who had highly HLA allele (1 to 3 of 6) mismatched dominant units had the highest day 100 grade III and IV aGVHD incidence of 37% (P = .009). This finding was confirmed in multivariate analysis (P = .053). In 83 patients evaluated for mycophenolic acid (MPA) troughs, those with a mean week 1 and 2 trough < .5 μg/mL had an increased day 100 grade III and IV aGVHD of 26% versus 9% (P = .063), and those who received a low total daily MMF dose and had a low mean week 1 and 2 MPA trough had a 40% incidence (P = .008). Higher MMF dosing or MPA troughs had no impact on engraftment after myeloablation. This analysis supports intensified MMF dosing in milligram per kilogram per day and MPA trough level monitoring early after transplantation in dCBT recipients.

Treatment of Central Venous Catheter‐Associated Deep Venous Thrombosis in Cancer Patients with Rivaroxaban

patients treated with conventional ABO identical, leukoreduced, irradiated transfusions. Long-term mortality in recipients of washed transfusions (20–40%) was half to two-thirds of that in the comparable historical comparison group and the current literature (60%) (Supporting Information Table 5). A limitation of these data, in addition to the lack of randomization, is that we did not collect detailed information on treatment regimens (e.g., choice and dose of anthracycline in AML). The striking differences we observed in long-term survival are unlikely solely due to progress in treatment regimens or supportive care. Identical differences were observed when we restricted the comparison to the years 2003–2005 and 2006–2008. For lower risk patients (favorable or intermediate cytogenetics; <46 years of age or younger) in New York State treated between 2006 and 2011 long-term mortality rate was 2.5-fold higher (50% versus 20%) in conventionally treated patients compared with recipients of washed transfusions. This approach has the potential to substantially improve outcomes for many patients with AML. This may be limited, at present, to younger patients with favorable or intermediate cytogenetics. Larger randomized trials will be required to determine whether our promising results are generalizable and reproducible, and whether they might be applicable to older patients (who often receive less intensive therapy), and to patients with other hematologic malignancies or solid tumors.

Spotlight on nilotinib in the treatment of chronic myelogenous leukemia

Nowhere has targeted therapy been more successful in the hematologic malignancy arena than chronic myelogenous leukemia (CML). By targeting the BCR-ABL fusion oncogene, the introduction of tyrosine-kinase inhibitors (TKIs) has dramatically improved the outcomes of this disease. Nilotinib is a second-generation TKI that initially gained approval for the treat- ment of imatinib-resistant or -intolerant disease for patients with chronic or accelerated-phase CML. Investigation in the first-line setting also demonstrated efficacy, and expanded nilotinibs approval to include therapy for patients with treatment-naive chronic-phase CML. Data also exist for blast-phase disease, which allows nilotinib to be an option for all phases. Nilotinibs place in therapy is continuously being expanded by research in novel areas, such as post-hematopoietic stem cell transplants for prevention of relapse and in the pediatric arena. With multiple TKIs now approved for the treatment of CML, delineating the pharmacologic distinctions of nilotinib is an asset when determining therapy. By understanding the pharmacokinetics and dependence on hepatic metabolism of nilotinib, the clinician can manage the potential toxicities, interactions, and unique dosing of this drug. The recognition of mechanisms of resistance, patient adherence, and cost-effectiveness are similarly significant considerations. Actively integrating these various specifics will allow clinicians to optimize nilotinib therapy for the CML patient.