Costs and Healthcare Resource Utilization for Obstructive Hypertrophic Cardiomyopathy With Septal Reduction Therapy.

BACKGROUND: Patients with obstructive hypertrophic cardiomyopathy (oHCM) and severe refractory symptoms may require invasive septal reduction therapies (SRTs), either surgical septal myectomy (SM) or transcatheter alcohol septal ablation (ASA). The main objective of this study was to quantify all-cause and oHCM-related healthcare resource utilization (HCRU) and costs for patients receiving SM or ASA. METHODS: This retrospective study utilized medical and pharmacy claims submitted during 2012-2020. HCRU and costs for 119 adults with oHCM who had at least 1 SM (n = 95) or ASA (n = 24) were compared for baseline and follow-up periods. RESULTS: The mean inpatient hospitalization stay was longer for SM (8.3 days) than ASA (6.0 days). Postprocedure HCM-related medication usage was greater following SM (98%) than ASA (88%). The mean number of HCM-related outpatient visits increased from pre- to post procedure (12.2 vs 15.9 in the SM group; 7.2 vs 9.5 in the ASA group), with most patients having at least 1 cardiology visit post procedure (86% of the SM group; 83% of the ASA group). Total mean HCM-related costs (reported in United States currency) increased with both procedures ($27,045 vs $119,772 in the SM group; $11,278 vs $54,351 in the ASA group), driven by increased inpatient hospitalization ($10,325 vs $112,923 in the SM group; $5509 vs $47,450 in the ASA group) and surgical costs ($6665 vs $92,031 in the SM group; $52 vs $44,815 in the ASA group). CONCLUSIONS: Our results indicate increasing costs for patients undergoing SRT, driven by inpatient hospitalizations and surgical costs. Commercially insured and Medicare Advantage patients with oHCM experience high healthcare costs and economic burden attributable to SRT.

A Phase 1 Dose-Escalation Study of the Cardiac Myosin Inhibitor Aficamten in Healthy Participants.

This phase 1, randomized, double-blind, placebo-controlled study of aficamten (formerly CK-3773274) in healthy adults identified a pharmacologically active range of doses and exposures. At doses that were pharmacologically active (single doses of ≤50 mg or daily dosing of ≤10 mg for 14 or 17 days), aficamten appeared to be safe and well tolerated. Adverse events were generally mild and no more frequent than with placebo. Pharmacokinetic assessments showed dose proportionality over the range of single doses administered, and pharmacokinetics were not affected by administration with food or in otherwise healthy individuals with a cytochrome P450 2D6 poor metabolizer phenotype. (A Single and Multiple Ascending Dose Study of CK-3773274 in Health Adult Subjects; NCT03767855).

Clinical Characteristics and Healthcare Resource Utilization among Patients with Obstructive Hypertrophic Cardiomyopathy Treated in a Range of Settings in the United States.

Obstructive hypertrophic cardiomyopathy (oHCM) has been studied primarily in comprehensive centers of excellence. Broadening the understanding of patients with oHCM in the general population may improve identification and treatment in other settings. This retrospective cohort study identified adults with oHCM from a large electronic medical record database comprising data from 39 integrated delivery networks (IBM Explorys; observational period: January 2009-July 2019). Clinical characteristics, healthcare resource utilization (HCRU), and outcomes were reported. Of 8791 patients, 53.0% were female and the mean index age was 61.8 years. Cardiovascular drugs prescribed included beta-blockers (80.5%), calcium channel blockers (46.0%), and disopyramide (2.4%). Over time, heart failure, atrial fibrillation, and ventricular arrhythmias increased. Surgical procedures included septal myectomy (22.0%), alcohol septal ablation (0.6%), and heart transplantation (0.3%). Implantable cardioverter defibrillators were present in 11.2% of patients. After initial septal reduction therapy (SRT), HCRU increased and 550 patients (27.7%) required a reintervention. Of the overall group, 2.7% experienced sudden cardiac arrest by end of study. In conclusion, this cohort of patients with oHCM had guideline-recommended drug therapy and procedures. Despite this, heart failure, atrial fibrillation, and ventricular arrhythmias increased, and more than a quarter of patients undergoing SRT required reintervention. These unresolved issues emphasize the unmet need for new, effective therapies for patients with oHCM.

Characteristics of Patients With Obstructive Hypertrophic Cardiomyopathy in Real-World Community-Based Cardiovascular Practices.

The clinical profile of patients with obstructive hypertrophic cardiomyopathy (oHC) is not well characterized, with little evidence outside selected referral populations. Using longitudinal medical claims data from a United States nationwide database, we retrospectively identified adults who were newly diagnosed with oHC. Clinical characteristics were compared from 1 year before diagnosis and at the 2-year follow-up. Patients (N = 1,841) with oHC (age 63 ± 15 years; 52% were male) with geographic representation across the United States were identified. Most patients received care within community-based cardiovascular practices and 7% at referral hypertrophic cardiomyopathy (HC) centers. Baseline diagnostic procedures included electrocardiogram (66%), echocardiogram (51%), magnetic resonance imaging (4%), and HC genetic testing (0.7%). Baseline co-morbidities were hypertension (59%), coronary artery disease (30%), diabetes (19%), and atrial fibrillation (19%). For all HC-related medications, use significantly increased after diagnosis. During follow-up, 144 patients (8%) received an implantable cardioverter-defibrillator for sudden death prevention, 99 underwent septal myectomy (5%), and 24 underwent alcohol septal ablation (1%). By the 1-year follow-up, 2% of patients had sudden cardiac arrest and 26% had atrial fibrillation, and heart failure increased from 16% to 27%. In conclusion, in a community-based population of patients with oHC, patients' age at diagnosis of oHC was older than reported for referral populations and patients had a significant co-morbidity burden. Cardiovascular medication use was appropriate, but the rate of guideline-supported surgical procedures was low.

Discovery of Aficamten (CK-274), a Next-Generation Cardiac Myosin Inhibitor for the Treatment of Hypertrophic Cardiomyopathy.

Hypercontractility of the cardiac sarcomere may be essential for the underlying pathological hypertrophy and fibrosis in genetic hypertrophic cardiomyopathies. Aficamten (CK-274) is a novel cardiac myosin inhibitor that was discovered from the optimization of indoline compound 1. The important advancement of the optimization was discovery of an Indane analogue (12) with a less restrictive structure-activity relationship that allowed for the rapid improvement of drug-like properties. Aficamten was designed to provide a predicted human half-life (t1/2) appropriate for once a day (qd) dosing, to reach steady state within two weeks, to have no substantial cytochrome P450 induction or inhibition, and to have a wide therapeutic window in vivo with a clear pharmacokinetic/pharmacodynamic relationship. In a phase I clinical trial, aficamten demonstrated a human t1/2 similar to predictions and was able to reach steady state concentration within the desired two-week window.

Effects of cash transfers on Children's health and social protection in Sub-Saharan Africa: differences in outcomes based on orphan status and household assets.

BACKGROUND: Unconditional and conditional cash transfer programmes (UCT and CCT) show potential to improve the well-being of orphans and other children made vulnerable by HIV/AIDS (OVC). We address the gap in current understanding about the extent to which household-based cash transfers differentially impact individual children's outcomes, according to risk or protective factors such as orphan status and household assets. METHODS: Data were obtained from a cluster-randomised controlled trial in eastern Zimbabwe, with random assignment to three study arms - UCT, CCT or control. The sample included 5,331 children ages 6-17 from 1,697 households. Generalized linear mixed models were specified to predict OVC health vulnerability (child chronic illness and disability) and social protection (birth registration and 90% school attendance). Models included child-level risk factors (age, orphan status); household risk factors (adults with chronic illnesses and disabilities, greater household size); and household protective factors (including asset-holding). Interactions were systematically tested. RESULTS: Orphan status was associated with decreased likelihood for birth registration, and paternal orphans and children for whom both parents' survival status was unknown were less likely to attend school. In the UCT arm, paternal orphans fared better in likelihood of birth registration compared with non-paternal orphans. Effects of study arms on outcomes were not moderated by any other risk or protective factors. High household asset-holding was associated with decreased likelihood of child's chronic illness and increased birth registration and school attendance, but household assets did not moderate the effects of cash transfers on risk or protective factors. CONCLUSION: Orphaned children are at higher risk for poor social protection outcomes even when cared for in family-based settings. UCT and CCT each produced direct effects on children's social protection which are not moderated by other child- and household-level risk factors, but orphans are less likely to attend school or obtain birth registration. The effects of UCT and CCT are not moderated by asset-holding, but greater household assets predict greater social protection outcomes. Intervention efforts need to focus on ameliorating the additional risk burden carried by orphaned children. These efforts might include caregiver education, and additional incentives based on efforts made specifically for orphaned children.

Asset ownership among households caring for orphans and vulnerable children in rural Zimbabwe: the influence of ownership on children's health and social vulnerabilities.

The high prevalence of human immunodeficiency virus/acquired immune deficiency syndrome in sub-Saharan Africa has resulted in a dramatic increase in orphans and vulnerable children (OVC) over the past decade. These children typically rely on extended family networks for support, but the magnitude of the crisis has resulted in traditional familial networks becoming overwhelmed and more economically and socially vulnerable. Previous research consistently demonstrates the positive influence of household asset ownership on children's well-being. Using data from impoverished households caring for OVC in rural Manicaland Province, Zimbabwe, this study explores the influence of household asset ownership on OVC health vulnerability (HV) and social vulnerability (SV). Findings indicate that asset ownership is associated with significantly lower SV, in terms of school attendance and birth registration. Yet, assets do not emerge as a direct influence of OVC HV as measured by disease and chronic illness, although having a chronically ill adult in the household increases HV. These findings suggest that asset ownership, specifically a combination of fixed and movable assets, may offset the influence of other risk factors for children's SV.

GSK-3 phosphorylation of the Alzheimer epitope within collapsin response mediator proteins regulates axon elongation in primary neurons.

Elevated glycogen synthase kinase-3 (GSK-3) activity is associated with Alzheimer disease. We have found that collapsin response mediator proteins (CRMP) 2 and 4 are physiological substrates of GSK-3. The amino acids targeted by GSK-3 comprise a hyperphosphorylated epitope first identified in plaques isolated from Alzheimer brain. Expression of wild type CRMP2 in primary hippocampal neurons or SH-SY5Y neuroblastoma cells promotes axon elongation. However, a GSK-3-insensitive CRMP2 mutant has dramatically reduced ability to promote axon elongation, a similar effect to pharmacological inhibition of GSK-3. Hence, we propose that phosphorylation of CRMP proteins by GSK-3 regulates axon elongation. This work provides a direct connection between hyperphosphorylation of these residues and elevated GSK-3 activity, both of which are observed in Alzheimer brain.

The potential role of tau protein O-glycosylation in Alzheimer's disease.

Single O-linked N-acetylglucosamine (O-GlcNAc) sugar residues can compete with phosphate groups to occupy specific sites on certain nuclear and cytosolic proteins. Here we show that inhibiting cellular kinase activities resulted in changes in protein O-glycosylation levels in heat-stable cytoskeletal protein fractions derived from primary neuronal cells. As increased phosphorylation of the microtubule-associated protein tau is one of the pathological hallmarks of Alzheimer's disease and glycosylation may play an influential role in this process. We observed a significant decrease in the protein O-GlcNAc glycosylation of a tau-enriched cytoskeletal fraction generated from AD post-mortem brain samples as compared with control, suggesting an inverse relationship between the two post-translational modifications. Finally, cells transfected with the cDNA coding for O-GlcNAc transferase (OGT) displayed altered tau phosphorylation patterns as compared with control cells, suggesting that changes in tau glycosylation may influence its phosphorylation state. The specificity of the changes in the phosphorylation of individual amino acid residues provides evidence for a targeted O-glycosylation of tau.

GABA(A) receptor composition is determined by distinct assembly signals within alpha and beta subunits.

Key to understanding how receptor diversity is achieved and controlled is the identification of selective assembly signals capable of distinguishing between other subunit partners. We have identified that the beta1-3 subunits exhibit distinct assembly capabilities with the gamma2L subunit. Similarly, analysis of an assembly box in alpha1-(57-68) has revealed an absolute requirement for this region in the assembly of alphabeta receptors. Furthermore, a selective requirement for a single amino acid (Arg-66), previously shown to be essential for the formation of the low affinity GABA binding site, is observed. This residue is critical for the assembly of alpha1beta2 but not alpha1beta1 or alpha1beta3 receptors. We have confirmed the ability of the previously identified GKER signal in beta3 to direct the assembly of betagamma receptors. The GKER signal is also involved in driving assembly with the alpha1 subunit, conferring the ability to assemble with alpha1(R66A) on the beta2 subunit. Although this signal is sufficient to permit the formation of beta2gamma2 receptors, it is not necessary for beta3gamma2 receptor formation, suggesting the existence of alternative assembly signals. These findings support the belief that GABA(A) receptor assembly occurs via defined pathways to limit the receptor diversity.

Assembly and cell surface expression of homomeric and heteromeric 5-HT3 receptors: the role of oligomerization and chaperone proteins.

The ability of differing subunit combinations of 5-HT3 receptors to form functional cell surface receptors was analyzed by a variety of approaches. The results revealed that 5-HT3 receptor assembly occurred within the endoplasmic reticulum (ER) and involved the interaction with chaperone proteins. The 5-HT3A subunit could assemble into functional homomeric receptors that were expressed on the cell surface. In contrast, the 5-HT3B subunit did not exhibit 5-hydroxytryptamine binding or function, could not assemble, and was efficiently retained and degraded within the ER. However, upon the coexpression of the 5-HT3A subunit, 5-HT3B could be "rescued" from the ER and transported to the cell surface to form functional heteromeric receptors with distinct functional characteristics. In support of the existence of homomeric 5-HT3 receptors in vivo, recombinantly expressed 5-HT3A receptors were capable of clustered cell surface expression in cortical neurons.