Characterization of direct oral anticoagulants use in adult hematopoietic stem cell transplant recipients

Direct oral anticoagulants (DOACs) for venous thromboembolism (VTE) treatment are of interest in oncology due to ease of administration and lack of need for therapeutic monitoring compared to other anticoagulants. Data supporting their use in patients with hematologic malignancies post-hematopoietic stem cell transplant (HCT) are limited. The purpose of the study is to characterize DOAC use in HCT patients. This multicenter, retrospective cohort analysis included allogeneic and autologous HCT recipients. The primary outcome was major bleeding. Secondary outcomes included clinically relevant non-major bleeding (CRNMB)/minor bleeding and VTE recurrence. Of 126 patients, 91 (72.2%) patients received an autologous HCT, and 35 (27.8%) patients received an allo-HCT. No major bleeding occurred in either transplant recipient groups. In autologous HCT recipients, CRNMB/minor bleeding occurred in four (4.4%) patients and VTE recurrence occurred in one (1.1%) patient. For allogeneic HCT recipients, CRNMB/minor bleeding occurred in five (14.3%) patients and VTE recurrence occurred in two (5.7%) patients. For patients that experienced a CRNMB, five (100%) of the allogeneic HCT and two (50%) of the autologous HCT recipients were thrombocytopenic at the time of bleeding. Only 38.5% of patients who experienced a drug-drug interaction requiring DOAC dose adjustment received the appropriate dose adjustment. DOACs were associated with low rates of recurrent VTE and no major bleeding events, similar to published data on DOAC use in the general cancer patient population. This suggests that DOACs may be safe therapeutic options with proactive management of drug interactions and careful monitoring for bleeding events, especially in the allogeneic HCT population where minor bleeding rates were slightly higher.

Predictors of lenalidomide maintenance duration after autologous stem cell transplant in patients with multiple myeloma

BACKGROUND

For patients with multiple myeloma (MM) who have undergone autologous stem cell transplant (auto-SCT), the immunomodulatory agent lenalidomide is a first-line option for maintenance therapy. Because longer durations of lenalidomide maintenance are associated with improved survival, identifying strategies to avoid premature cessation of maintenance is an important priority in the post-transplant setting.

OBJECTIVES

The primary objective of this analysis was to identify specific clinical predictors of lenalidomide treatment duration that could guide optimal medication management. Key secondary objectives included predictors of intolerable toxicity, rationale for lenalidomide dose reduction/discontinuation, and characterization of dose adjustments.

STUDY DESIGN

This retrospective, multi-center cohort study included adults with MM who underwent auto-SCT and initiated maintenance lenalidomide between 01/01/2012 and 02/28/2021. Variables assessed as potential predictors of maintenance duration or intolerable toxicity included age, body mass index (BMI), Eastern Cooperative Oncology Group (ECOG) performance status at time of auto-SCT, renal function, initial lenalidomide dose, use of combination maintenance therapy, and cytogenetic risk category.

RESULTS

Among 299 patients included, the median age at time of auto-SCT was 62 years (range 30-77). The majority of patients had standard-risk cytogenetics (64%) and an ECOG performance status of 0 or 1 (72%). In the overall population, the median duration of maintenance was 1.3 years (range 0.3-8.6 years). The median initial dose of lenalidomide was 10 mg daily (range 2.5-25 mg). During the study period, 35% of patients had a dose reduction due to toxicity, 21% stopped lenalidomide due to disease progression, and 19% stopped due to toxicity. Multivariate linear regression analyses did not identify any significant predictors of lenalidomide duration or discontinuation due to intolerable toxicity. The most frequently reported toxicities leading to discontinuation were cytopenias, rash, and fatigue.

CONCLUSION

This analysis did not identify any significant risk factors to predict the duration of lenalidomide maintenance or discontinuation for toxicity following auto-SCT in patients with MM. While limited by the retrospective design and relatively small sample size, our findings suggest that a priori lenalidomide dose reductions based on patient co-morbidities or performance status may not substantially affect the duration of lenalidomide maintenance.

Characterization of a multidisciplinary team's role in hospital discharge for patients receiving hypomethylating agents with venetoclax as induction therapy for acute myeloid leukemia

PURPOSE

Venetoclax combined with a hypomethylating agent (HMA) has become the standard of care for elderly/unfit patients with newly diagnosed acute myeloid leukemia (AML). This study is aimed at characterizing the impact of an interdisciplinary team on the length of stay (LOS) of patients with newly diagnosed AML receiving venetoclax with an HMA.

METHODS

This retrospective observational study included patients with AML who received HMA with venetoclax as an initial treatment between December 2015 and July 2021. The primary outcome was the median LOS during induction stratified by HMA. Secondary outcomes included barriers to hospital discharge, incidence of tumor lysis syndrome (TLS), response rates, and utilization of the institution's prescription assistance program (PAP).

RESULTS

Seventy-eight patients were included in our analysis: 51 received azacitidine/venetoclax, and 27 received decitabine/venetoclax. The median LOS from therapy initiation was eight days (range 7-38) for the azacitidine group and six days (range 5-26) for the decitabine group. The most common barriers to discharge were transfusion dependence (33 patients, 42.3%) and insurance coverage (12 patients, 15.4%). Twelve patients (15.3%) had tumor lysis syndrome during hospital admission, and 20 (25.6%) were readmitted during induction. Twenty-three patients (29.5%) required financial assistance for AML care, and a pharmacy-led PAP generated approximately $342,646 in cost savings.

CONCLUSION

The utilization of an interdisciplinary AML team to target early hospital discharge proved to be safe and effective and led to a reduction in costs for the health system. Future research may identify select patients who may be suitable for earlier discharge or outpatient induction.

Effects of antibiotic therapy on Pseudomonas aeruginosa-induced lung injury in a rat model

The effect of antibiotics on the acute lung injury induced by virulent Pseudomonas aeruginosa PA103 was quantitatively analyzed in a rat model. Lung injury was induced by the instillation of PA103 directly into the right lower lobes of the lungs of anesthetized rats. The alveolar epithelial injury, extravascular lung water, and total plasma equivalents were measured as separate, independent parameters of acute lung injury. Four hours after the instillation of PA103, all the parameters were increased linearly depending on the dose of P. aeruginosa. Next, we examined the effects of intravenously administered antibiotics on the parameters of acute lung injury in D-galactosamine-sensitized rats. One hour after the rats received 10(7) CFU of PA103, an intravenous bolus injection of aztreonam (60 mg/kg) or imipenem-cilastatin (30 mg/kg) was administered. Despite an MIC indicating resistance, imipenem-cilastatin improved all the measurements of lung injury; in contrast, aztreonam, which had an MIC indicating sensitivity, did not improve any of the lung injury parameters. The antibiotics did not generate different quantities of plasma endotoxin; therefore, endotoxin did not appear to explain the differences in lung injury. This in vivo model is useful to quantitatively compare the efficacies of parenteral antibiotic administration on Pseudomonas airspace infections.

Thermal mechanical analysis of frozen solutions of mannitol and some related stereoisomers: evidence of expansion during warming and correlation with vial breakage during lyophilization

The mechanical properties of frozen mannitol, L-iditol, dulcitol, and sorbitol solutions were measured as a function of temperature during warming (after freezing) using a thermal mechanical analyzer (TMA). The mannitol sample first underwent a contractive phase starting at 30 degrees C and ending at -25 degrees C. This was followed by an initially rapid, then less rapid expansive phase which continued until melting occurred. These events provide direct evidence that mannitol solutions undergo an expansion during warming after "fast" freezing and also corroborate the vial breakage observed when mannitol solutions are frozen and thawed or freeze-dried in glass vials. Of the other stereoisomers studied, only dulcitol had an expansive phase although at a slower rate than mannitol. Its solution was found to cause vial breakage also but only at fill volumes higher than mannitol fill volumes. TMA is a useful technique for studying dimensional changes in the frozen state, with important implications for solving vial breakage problems in freeze-drying.