Cost-effectiveness of prophylaxis with recombinant vs plasma-derived VWF in severe von Willebrand disease in the United States.

ABSTRACT: We evaluated the cost-effectiveness of prophylaxis with recombinant von Willebrand factor (rVWF) vs with plasma-derived von Willebrand factor (pdVWF) for patients with severe Von Willebrand disease. We found that rVWF is a cost-saving factor replacement compared with pdVWF across all willingness-to-pay thresholds in the United States.

Cost-effectiveness of rapid vs in-house vs send-out ADAMTS13 testing for immune thrombotic thrombocytopenic purpura.

ABSTRACT: While awaiting confirmatory results, empiric therapy for patients suspected to have immune thrombotic thrombocytopenic purpura (iTTP) provides benefits and also accrues risks and costs. Rapid assays for ADAMTS13 may be able to avoid the cost and risk exposure associated with empiric treatment. We conducted, to our knowledge, the first cost-effectiveness evaluation of testing strategies with rapid vs traditional ADAMTS13 assays in patients with intermediate- to high-risk PLASMIC scores, with and without caplacizumab use. We built a Markov cohort simulation with 4 clinical base-case analyses: (1) intermediate-risk PLASMIC score with caplacizumab; (2) intermediate-risk PLASMIC score without caplacizumab; (3) high-risk PLASMIC score with caplacizumab; and (4) high-risk PLASMIC score without caplacizumab. Each of these evaluated 3 testing strategies: (1) rapid assay (<1-hour turnaround); (2) in-house fluorescence resonance energy transfer (FRET)-based assay (24-hour turnaround); and (3) send-out FRET-based assay (72-hour turnaround). The primary outcome was the incremental net monetary benefit reported over a 3-day time horizon and across accepted willingness-to-pay thresholds in US dollars per quality-adjusted life-year (QALY). While accruing the same amount of QALYs, the rapid assay strategy saved up to $46 820 (95% CI, $41 961-$52 486) per patient tested. No parameter variation changed the outcome. In probabilistic sensitivity analyses, the rapid assay strategy was favored in 100% (3 base cases and scenario analyses) and 99% (1 base-case and scenario analysis) across 100 000 Monte Carlo iterations within each. Rapid ADAMTS13 testing for patients with intermediate- or high-risk PLASMIC scores yields significant per patient cost savings, achieved by reducing the costs associated with unnecessary therapeutic plasma exchange and caplacizumab therapy in patients without iTTP.

Global Health Resource Utilization and Cost-Effectiveness of Therapeutics and Diagnostics in Immune Thrombotic Thrombocytopenic Purpura (TTP).

In this review, we examine the current landscape of health resource utilization and cost-effectiveness data in the care of patient populations with immune thrombotic thrombocytopenic purpura. We focus on the therapeutic (therapeutic plasma exchange, glucocorticoids, rituximab, caplacizumab) and diagnostic (ADAMTS13 assay) health technologies employed in the care of patients with this rare disease. Health resource utilization and cost-effectiveness data are limited to the high-income country context. Measurement of TTP-specific utility weights in the high-income country context and collection of health resource utilization data in the low- and middle-income country settings would enable an evaluation of country-specific quality-adjusted life expectancy and cost-effectiveness of these therapeutic and diagnostic health technologies. This quantification of value is one way to mitigate cost concerns where they exist.

Impact of Prophylactic Antibacterials on Coagulation Profiles and Bleeding in Patients with Acute Myeloid Leukemia/Myelodysplastic Syndrome.

Patients with acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS) often receive antibacterial prophylaxis. Antibacterial agents can cause elevations in the prothrombin time and international normalized ratio (INR). The impact of prophylactic antibacterials on the coagulation profiles and bleeding risk in patients with AML/MDS is unknown. We evaluated patients with AML or MDS who were being admitted to the hospital. The cohort was divided into two groups of patients: (1) those receiving and (2) those not receiving prophylactic antibacterials, at the time of admission. We conducted a retrospective cohort study of adult patients with AML/MDS admitted to Yale-New Haven Hospital between 2015-2019. The study was approved by the Yale Institutional Review Board. Inclusion criteria included patients >18 years old with a diagnosis of AML or MDS admitted to the hospital. We identified 150 individual patient encounters with active AML/MDS admitted to Yale-New Haven of which 32 occurred while on and 118 while off antibacterial prophylaxis. Median duration of pre-admission antibacterial exposure was 2 (range: 0.07-24) months. Patients on antibacterial prophylaxis had higher INR (median 1.14 vs. 1.03, p = 0.0002), and higher partial thromboplastin time prolongation (median 26.5 vs. 24.3, p < 0.0014), than patients without antibacterial prophylaxis. Patients without antibacterial prophylaxis had higher rates of bleeding using the ISTH-defined criteria (24.6% vs. 6.3%, p = 0.043), including higher rates of ISTH major (2 vs. 0) and clinically relevant bleeding (9 vs. 0). Patients with AML/MDS on antibacterial prophylaxis were more likely to have an abnormal coagulation profile when compared with their counterparts not on prophylaxis. Conversely, rates of bleeding were higher in patients not on prophylaxis. These data suggest that prophylactic antibacterials do not increase bleeding risk in patients with AML/MDS.

Hypomethylating Agents and FLT3 Inhibitors As Maintenance Treatment for Acute Myeloid Leukemia and Myelodysplastic Syndrome After Allogeneic Hematopoietic Stem Cell Transplantation-A Systematic Review and Meta-Analysis.

BACKGROUND: Disease relapse remains the major cause of death among patients with acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS) who receive an allogeneic hematopoietic cell transplant (allo-HCT). Maintenance treatment with FLT3 inhibitors and hypomethylating agents (HMA) has been studied in various clinical trials with mixed results. OBJECTIVE: To synthesize the current evidence on the efficacy and safety of FLT3 inhibitors and HMA for maintenance therapy after allo-HCT in AML and MDS. METHODS: For this systematic review and meta-analysis Cochrane Library, Google Scholar, Ovid Medline, Ovid Embase, PubMed, Scopus, and Web of Science Core Collection were searched from inception to March 2021 for studies on maintenance therapies after allo-HCT in AML and MDS. Studies were excluded if they were reviews, commentaries, case series with <5 patients, or basic research articles, not published in English, not on post-allo-HCT maintenance with FLT3 inhibitors or HMA in AML or MDS, or if they were clinical trials without published results or duplicate publications from the same patient cohort. Studies with insufficient reporting of the primary endpoint (2-year overall survival [OS]) and studies using FLT3 inhibitors or HMA for pre-emptive treatment of imminent relapse based on positive measurable residual disease testing were excluded. Random-effects models were used to pool response rates for the primary outcome of 2-year OS. Hazard ratios (HR) for death and relapse were calculated for studies that included a control group. Rates of relapse-free survival (RFS), non-relapse mortality, and acute and chronic graft-versus-host-disease (GVHD) were studied as secondary endpoints. Downs and Black checklist and risk of bias assessments were used to gauge the quality of individual studies. The study protocol has been registered on PROSPERO (CRD42020187298). RESULTS: Our search strategy identified 5559 studies. Twenty-one studies with a total of 809 patients were included in the meta-analysis. The 2-year OS rates were 81.7% (95% confidence interval [CI], 73.8%-87.7%) and 65.7% (95% CI, 55.1%-74.9%) among patients treated with FLT3 inhibitors and HMA, respectively. In sensitivity analyses restricted to studies that included a control group, maintenance therapy with FLT3 inhibitors (HR for death = 0.41; 95% CI, 0.26-0.62) or HMA (HR = 0.45; 95% CI, 0.31-0.66) appeared superior to no maintenance therapy. The 2-year RFS rates were 79.8% (95% CI, 75.0%-83.9%) and 62.4% (95% CI, 50.6%-72.9%) among patients treated with FLT3 inhibitors and HMA, respectively. Rates of any grade acute and chronic GVHD were 33.1% (95% CI, 25.4%-41.8%; grade 3/4: 16.5%) and 42.5% (95% CI, 26.3%-60.4%) among FLT3 inhibitor and 42.7% (95% CI, 33.5%-52.4%; grade 3/4: 8.1%) and 41.5% (95% CI, 32.0%-51.6%) among HMA-treated patients, respectively. CONCLUSION: Maintenance therapy with either FLT3 inhibitors or HMA after allo-HCT can lead to prolonged and improved OS and RFS with a favorable safety profile. Additional studies are needed to define the optimal duration of treatment, the role of measurable residual disease status, and transplant characteristics in patient selection.

BiTEs, DARTS, BiKEs and TriKEs-Are Antibody Based Therapies Changing the Future Treatment of AML?

Nearly four decades after their conceptualization, antibody-based therapies are slowly being added to the treatment landscape of acute myeloid leukemia (AML). While the antibody-drug conjugate gemtuzumab ozogamicin is the only antibody-based therapy that has been approved for AML treatment thus far, several bispecific antibodies have been developed and shown early encouraging results. Bispecific antibodies comprise a wide variety of constructs that share the common concept of simultaneous binding of a surface target on malignant cells and most commonly CD3 on T cells leading to an endogenous, HLA-independent, immune response against malignant cells. However, the use of bispecific antibodies in AML has been limited by the absence of highly specific leukemia-associated antigens leading to on-target, off-leukemia side effects as well as reduced efficacy due to antigen escape. Herein, we discuss the history and evolution of bispecific T cell engagers as well as various adaptations such as dual affinity retargeting antibodies, bi- and tri-specific killer engager antibodies. Common side effects including cytokine release syndrome and management thereof are highlighted. Lastly, we expound on the future direction and integration of such antibody-based therapies with other immunotherapies (programmed cell death-1 inhibitors and chimeric antigen receptor T cells).

Integrating Cultural Awareness into Medical Gross Anatomy Instruction.

Medical students need to understand how culture and patient management relate in order to provide optimal care to a diverse society. Multiple studies call for more cultural training in medical education. Some studies show that well-intentioned cultural competency curriculum can reinforce stereotypes, yet it is essential for educators to discuss varying identities with our students in their training in order to avoid the implication that white is the default patient identity. Our study evaluates a pilot, novel approach for integrating cultural content into the biomedical sciences, specifically gross anatomy. Clinical vignette practice questions were developed as tools to help students expand their anatomical knowledge and cultural and socioeconomic awareness, taking special consideration to avoid stereotypical presentations. We evaluated class of 2021 students' self-reported cultural awareness and ability to utilize culturally relevant information through completion of a survey in fall 2017 (pre) and winter 2017 (post). The students were surveyed on their ability to recognize and/or integrate culturally relevant information. Twenty-one students (n = 21) participated. There was significant improvement in the overall cultural awareness score between the pre- and post-surveys (pre mean = 3.54, while post mean = 3.81; p = 0.016). The most dramatic domains that students became aware of included incorporating culturally relevant information into a treatment plan and communicating with sensitivity and respect when caring for patients. Culturally informed curriculum does not need to be limited to the humanities courses in medical education. Direct integration into biomedical sciences is a novel approach to help students gain exposure to biomedical and cultural content simultaneously.

N-Acetyltransferase 2 Genotype-Dependent N-Acetylation of Hydralazine in Human Hepatocytes.

Hydralazine is used in the treatment of essential hypertension and is under investigation for epigenetic therapy in the treatment of neoplastic and renal diseases. N-acetyltransferase (NAT) 2 exhibits a common genetic polymorphism in human populations. After recombinant expression in yeast, human NAT2 exhibited an apparent Lineweaver-Burk constant (K-m) value (20.1 ± 8.8 µM) for hydralazine over 20-fold lower than the apparent K-m value (456 ± 57 µM) for recombinant human NAT1 (P = 0.0016). The apparent Vmax value for recombinant human NAT1 (72.2 ± 17.9 nmol acetylated/min/mg protein) was significantly (P = 0.0245) lower than recombinant human NAT2 (153 ± 15 nmol acetylated/min/mg protein), reflecting 50-fold higher clearance for recombinant human NAT2. Hydralazine NAT activities exhibited a robust acetylator gene dose response in cryopreserved human hepatocytes both in vitro and in situ. Hydralazine NAT activities in vitro differed significantly with respect to NAT2 genotype at 1000 (P = 0.0319), 100 (P = 0.002), and 10 µM hydralazine (P = 0.0029). Hydralazine NAT activities differed significantly (P < 0.001) among slow acetylator hepatocytes, (NAT2*5B/*5B > NAT2*5B/*6A > NAT2*6A/*6A). The in situ hydralazine N-acetylation rates differed significantly with respect to NAT2 genotype after incubation with 10 (P = 0.002) or 100 µM (P = 0.0015) hydralazine and were higher after incubation with 100 µM (10-fold) than with 10 µM (4.5-fold) hydralazine. Our results clearly document NAT2 genotype-dependent N-acetylation of hydralazine in human hepatocytes, suggesting that hydralazine efficacy and safety could be improved by NAT2 genotype-dependent dosing strategies.