Dynamics of magnetization at infinite temperature in a Heisenberg spin chain

Understanding universal aspects of quantum dynamics is an unresolved problem in statistical mechanics. In particular, the spin dynamics of the one-dimensional Heisenberg model were conjectured as to belong to the Kardar-Parisi-Zhang (KPZ) universality class based on the scaling of the infinite-temperature spin-spin correlation function. In a chain of 46 superconducting qubits, we studied the probability distribution of the magnetization transferred across the chain's center, [Formula: see text]. The first two moments of [Formula: see text] show superdiffusive behavior, a hallmark of KPZ universality. However, the third and fourth moments ruled out the KPZ conjecture and allow for evaluating other theories. Our results highlight the importance of studying higher moments in determining dynamic universality classes and provide insights into universal behavior in quantum systems.

Stable quantum-correlated many-body states through engineered dissipation

Engineered dissipative reservoirs have the potential to steer many-body quantum systems toward correlated steady states useful for quantum simulation of high-temperature superconductivity or quantum magnetism. Using up to 49 superconducting qubits, we prepared low-energy states of the transverse-field Ising model through coupling to dissipative auxiliary qubits. In one dimension, we observed long-range quantum correlations and a ground-state fidelity of 0.86 for 18 qubits at the critical point. In two dimensions, we found mutual information that extends beyond nearest neighbors. Lastly, by coupling the system to auxiliaries emulating reservoirs with different chemical potentials, we explored transport in the quantum Heisenberg model. Our results establish engineered dissipation as a scalable alternative to unitary evolution for preparing entangled many-body states on noisy quantum processors.

Measurement-induced entanglement and teleportation on a noisy quantum processor

Measurement has a special role in quantum theory1: by collapsing the wavefunction, it can enable phenomena such as teleportation2 and thereby alter the 'arrow of time' that constrains unitary evolution. When integrated in many-body dynamics, measurements can lead to emergent patterns of quantum information in space-time3-10 that go beyond the established paradigms for characterizing phases, either in or out of equilibrium11-13. For present-day noisy intermediate-scale quantum (NISQ) processors14, the experimental realization of such physics can be problematic because of hardware limitations and the stochastic nature of quantum measurement. Here we address these experimental challenges and study measurement-induced quantum information phases on up to 70 superconducting qubits. By leveraging the interchangeability of space and time, we use a duality mapping9,15-17 to avoid mid-circuit measurement and access different manifestations of the underlying phases, from entanglement scaling3,4 to measurement-induced teleportation18. We obtain finite-sized signatures of a phase transition with a decoding protocol that correlates the experimental measurement with classical simulation data. The phases display remarkably different sensitivity to noise, and we use this disparity to turn an inherent hardware limitation into a useful diagnostic. Our work demonstrates an approach to realizing measurement-induced physics at scales that are at the limits of current NISQ processors.

Non-Abelian braiding of graph vertices in a superconducting processor

Indistinguishability of particles is a fundamental principle of quantum mechanics¹. For all elementary and quasiparticles observed to date-including fermions, bosons and Abelian anyons-this principle guarantees that the braiding of identical particles leaves the system unchanged^2,3. However, in two spatial dimensions, an intriguing possibility exists: braiding of non-Abelian anyons causes rotations in a space of topologically degenerate wavefunctions^4-8. Hence, it can change the observables of the system without violating the principle of indistinguishability. Despite the well-developed mathematical description of non-Abelian anyons and numerous theoretical proposals^9-22, the experimental observation of their exchange statistics has remained elusive for decades. Controllable many-body quantum states generated on quantum processors offer another path for exploring these fundamental phenomena. Whereas efforts on conventional solid-state platforms typically involve Hamiltonian dynamics of quasiparticles, superconducting quantum processors allow for directly manipulating the many-body wavefunction by means of unitary gates. Building on predictions that stabilizer codes can host projective non-Abelian Ising anyons^9,10, we implement a generalized stabilizer code and unitary protocol²³ to create and braid them. This allows us to experimentally verify the fusion rules of the anyons and braid them to realize their statistics. We then study the prospect of using the anyons for quantum computation and use braiding to create an entangled state of anyons encoding three logical qubits. Our work provides new insights about non-Abelian braiding and, through the future inclusion of error correction to achieve topological protection, could open a path towards fault-tolerant quantum computing.

Impact of clinical trial enrollment on episode costs in the Oncology Care Model (OCM)

6513

Background: Clinical trials are critical for improving outcomes for patients with cancer. However, there is some concern from health insurers that clinical trial participation can increase total cost of care for cancer patients. We investigated the impact of clinical trial participation on total costs paid by Medicare during the OCM program in a large community-based practice. Methods: Tennessee Oncology (TO) is a community oncology practice comprising over 90 oncologists across 30 sites of care. We linked TO trial data and electronic medical record data with OCM data for episodes of care from 2016-2018. To assess the impact of trial participation on total cost relative to routine care, we created matched comparator groups for each OCM episode based on cancer type, metastatic status, number of comorbidities, performance status, and age. Patients with breast cancer receiving hormone therapy only were excluded. Absolute and percent cost differences between groups were calculated for episodes that had a comparator group size of five or greater. Differences in total cost for trial episodes were compared to non-trial episodes, and significance was assessed using the Mann–Whitney U test. We also studied the impact of trial participation on receipt of active treatment in the last 14 days of life (TxEOL), hospice use, and hospitalizations. Results: During the study period, 8,026 completed OCM episodes met study criteria. Patients were enrolled in a clinical trial for 459 of these episodes. On average, episodes during which patients were on trial cost $5,973 less than matched non-trial episodes (Table), independent of early versus late-phase trial. Most savings resulted from decreased drug costs. There were no differences in rates of TxEOL (15% vs. 14% p=1.0), rates of hospitalizations (31% vs. 30% p=0.54), or hospice use (52% vs. 62% p=0.08) between trial and non-trial episodes. Median difference from comparator group average cost was significantly lower for clinical trial episodes (-18% vs. -6%, p<0.01). Conclusions: In the community setting, total costs paid by Medicare for patients participating in clinical trials during OCM episodes were lower than costs for similar patients receiving routine care. Clinical trial participation did not adversely impact end-of-life care or likelihood of hospitalization. These findings suggest that patient participation in clinical trials does not increase total cost of care nor enhance financial risk to payers.[Table: see text]

Concentrations, distribution, and risk assessment of heavy metals in the iron tailings of Yeshan National Mine Park in Nanjing, China

For the first time, a field survey was conducted to investigate the present situation, vertical distribution and ecological risks of heavy metals (Cu, Zn, Mn, Cr, Pb and As) from 21 in-situ samples drilled out from Yeshan iron mine tailings in the Jiangsu Province of China. The heavy metal contents obtained for the tailing wastes in decreasing order were as follows: Mn > Cu > Zn > As > Cr > Pb. The contents of heavy metals varied with depth, and the variation trends were not completely consistent. Vertical distribution profiles showed that heavy metals accumulated in certain strata. Both the monomial potential ecological risk factor (E) and the risk quotient (RQ) showed a high ecological risk for Cu, Mn and As. The comprehensive ecological risk index (RI) also indicated that the wastes presented a high ecological risk level, to which Cu, Mn and As were the key contributors. Our study showed that the health of individuals, especially children, living in the mining-impacted areas could be affected by the potential noncarcinogenic risk of copper, manganese and the carcinogenic risk of arsenic.

Use of antiemetic prophylaxis and oral breakthrough medication for highly emetogenic chemotherapy (HEC) in a large community oncology network

253

Background: Prophylaxis for highly emetogenic chemotherapy (HEC) is well established in clinical guidelines, but real-world treatment patterns are unclear. Today, consistent use of prophylaxis is more easily accomplished due to the incorporation of ordering premeds into the workflow prior to administration of intravenous chemotherapy. However, prescription of oral agents for treatment of breakthrough chemotherapy induced nausea and vomiting (CINV) is less consistent and standardized and has a scant evidence base. In an effort to standardize utilization, we evaluated the use of prophylaxis and oral breakthrough medications in a large national community oncology network. Methods: Data from electronic medical records at five practices comprising over 100 clinic sites was analyzed to examine the frequency of guideline-recommended triplet 5-HT3 receptor antagonist, NK-1 receptor antagonist, and corticosteroid use for prophylaxis prior to the administration of HEC agents. Oral breakthrough medication use and preference was also analyzed. Data was collected and analyzed at the practice level. Results: We identified 2645 patients that received HEC between 1/1/2019 and 5/8/2020. We found consistently high utilization of guideline-concordant triplet prophylaxis regimens for patients receiving HEC, ranging from 90-100% at each of the five practices. In addition, most patients (mean 83%, range 67% - 94%) received a prescription for at least one oral breakthrough medication, but the agent(s) utilized varied widely across practices (Table). Ondansetron was the most commonly prescribed oral breakthrough medication (mean 68%, range 53% - 88%), while olanzapine use for either prophylaxis or breakthrough CINV across practices ranged from 1% - 4%. Conclusions: In this national community oncology network, standard recommended triplet agent prophylaxis for HEC was delivered successfully. However, opportunity exists to increase appropriate use of olanzapine and reduce variation of oral breakthrough antiemetic medications in order to optimize clinical care. [Table: see text]

Real-world patterns of chemotherapy and immunotherapy utilization at end of life in a large community oncology network

22

Background: End-of-life anti-neoplastic treatment does not improve quality of life nor prolong survival of advanced cancer patients. It is also not cost-effective. To-date, there has been little data examining real-world patterns of chemotherapy and immunotherapy treatment at end of life. We investigated use of chemotherapy and/or immunotherapy in the last 14 days of life across a community oncology network of 5 practices, 100 sites of care, and 160 oncology providers. Methods: Using a real-time, network-wide database, we identified patients with solid tumor malignancies who died during an episode of active treatment, defined as having received intravenous (IV) chemotherapy and/or immunotherapy within 90 days of death. We then identified patients in this cohort who received IV chemotherapy and/or IV immunotherapy within 14 days of death (TxEoL). We studied TxEoL patterns by cancer type, treatment type, line of therapy, patient age, patient race, and oncology provider years in practice. Statistical significance was assessed using Pearson’s Chi-squared test. Results: 2,858 qualifying solid tumor cancer patients with dates of death between 1/1/2019 and 5/31/2020 were identified. Observed rates of TxEoL were 16.7% for immunotherapy alone vs. 19.6% for chemotherapy +/- immunotherapy (p = 0.09). We found high variation in TxEoL across 132 oncologists that had 5 or more deceased patients (range: 0% to 50%, mean: 19.2%, median: 19.6%). We found no association of TxEOL with physician years in practice, patient age or race. Rates of TxEoL in the first-line setting were significantly higher than in second-line setting or later (23.3% versus 16.4%, p < 0.01). Patients with head and neck, pancreatic, and hepatobiliary malignancies were the most likely to receive TxEoL, while patients with prostate, brain, and ovarian malignancies were the least likely to receive TxEoL. Conclusions: Our data and method identified wide variation in TxEoL patterns across a large community oncology network, suggesting room for provider-level interventions to improve treatment decisions in patients at high risk of death. Studies within our group, such as examining the impact of palliative care referrals on IV anti-cancer treatment in patients potentially facing end of life, are ongoing.

Feasibility of and associated cost savings from transitioning to therapeutic biosimilar use in a large community oncology network

9

Background: The use of biosimilar drugs in the treatment of cancer offer an opportunity for oncology providers to decrease total cost of care while preserving quality. However, it remains unclear whether providers and patients may resist biosimilar use due to concerns over safety and efficacy. Our national network of 5 practices with over 100 clinics committed to a conversion to therapeutic biosimilars for trastuzumab and bevacizumab after their introduction in July 2019. Methods: Common steps to foster therapeutic biosimilar conversion included frequent communication from medical directors to providers and staff, incorporation of biosimilars into default treatment regimen orders, providing clinical teams lists identifying candidates for conversion, and tracking reasons why biosimilar switch did not occur. Most practices prioritized converting patients initiating new treatments, then later transitioning patients receiving maintenance therapy. This phased approach was taken to ensure that prior authorization and patient consent could be obtained prior to conversion. Rates of biosimilar use were calculated by comparing the number of administrations for which a biosimilar was given to the total number of administrations for which a biosimilar could have been given. Cost savings were calculated by comparing the difference in Medicare allowed rates for each originator and biosimilar drug pair at the time of administration. Results: Biosimilar use increased over time at all practices, from 0% to an average of 67% for trastuzumab and 78% for bevacizumab. The decrease in cost attributed to the use of biosimilars in the study period totaled over $4.4 million. Challenges to biosimilar use included physician preference for the originator drug, difference in preferred agents across payers, and challenges with biosimilar drug storage. Patients rarely had concerns over efficacy and safety. Conclusions: Therapeutic biosimilar adoption in a large oncology network is feasible and can lead to significant cost savings. [Table: see text]

Impact of a built-in electronic medical record prompt on guideline-recommended prophylactic antiviral usage in patients with multiple myeloma receiving proteasome inhibitors

248

Background: Guidelines support the use of prophylactic antivirals to prevent reactivation of herpes varicella in patients with multiple myeloma (MM) on proteasome inhibitors (PI). In our network of five oncology practices spanning over 100 clinic sites, one practice has a built-in prompt for acyclovir use in patients receiving a PI, while the other four practices do not. We used this natural experiment to determine the impact of this prompt on appropriate prophylactic antiviral usage in this patient population. Methods: We retrospectively identified all patients in our network with MM beginning a regimen containing a PI between 1/1/19 and 5/28/20. Of these patients, we identified those with documentation of a prescription for acyclovir or valacyclovir before or within 2 days of the first PI dose. We compared prophylactic usage across five practices. Practice 1 had built a prompt for the prescription of acyclovir in regimens containing bortezomib or carfilzomib within the electronic medical record (EMR) which both reminded physicians and nurses and simplified the prescribing process. No other practices had similar EMR prompts. Results: We identified 583 patients with MM who received a PI during the study period. Wide variation in rates of prophylactic antiviral usage existed across the five practices (range 21%-94%). The highest rate of prophylactic antiviral usage was practice 1 (94%). This was the only practice with a built-in EMR prompt for acyclovir usage in PI regimens. We found no association between use of prophylactic antivirals and individual provider-level volume of patients with MM. Conclusions: Use of prophylactic therapy is heterogeneous across practices. A comprehensive treatment plan containing a prompt in the EMR can markedly increase appropriate utilization. We plan to add an EMR prompt and analytics-driven reminders across our network to improve utilization of all guideline-recommend, orally administered prophylactic medications. [Table: see text]

Impact of embedded palliative care providers compared to externally available palliative care services on the number of patients receiving palliative care referrals in a large community oncology practice

12103

Background: Palliative care improves quality of life and may increase overall survival in patients with solid tumor malignancies. Despite having the ability to refer patients to in-home and external palliative care services, we observed low palliative care referral rates in our practice of 90 oncologists across 30 clinics. We tested whether embedding palliative care providers directly in clinic would improve palliative care referral rates for solid tumor patients. Methods: Between 2017 and 2020, we embedded an independent palliative care provider into five clinics across middle Tennessee. Access to external palliative care services was present both before and after the intervention. Using data from our EHR and billing systems, we performed a pre-post analysis measuring palliative care referrals in the six-month periods immediately before (pre-intervention period) and after (post-intervention period) a palliative care provider was embedded in each clinic. Statistical significance was assessed using Welch’s two sample t-test. Results: 8,636 unique solid tumor patients were seen in the five clinics during the study periods (Table). Despite having the ability to refer patients to external palliative care services in the pre-intervention period, the placement of a palliative care provider into clinic increased the number of solid tumor patients that received a palliative care referral per month at all clinics (min.: 200%; max.: 990%; median: 600%). Four of the five increases were statistically significant (p-values < 0.05). Conclusions: Even when external palliative care services are available, embedding palliative care providers into community oncology clinics significantly increases the rate of palliative care referrals for solid tumor patients. [Table: see text]

Deep Transfer Learning and Radiomics Feature Prediction of Survival of Patients with High-Grade Gliomas

BACKGROUND AND PURPOSE

Patient survival in high-grade glioma remains poor, despite the recent developments in cancer treatment. As new chemo-, targeted molecular, and immune therapies emerge and show promising results in clinical trials, image-based methods for early prediction of treatment response are needed. Deep learning models that incorporate radiomics features promise to extract information from brain MR imaging that correlates with response and prognosis. We report initial production of a combined deep learning and radiomics model to predict overall survival in a clinically heterogeneous cohort of patients with high-grade gliomas.

MATERIALS AND METHODS

Fifty patients with high-grade gliomas from our hospital and 128 patients with high-grade glioma from The Cancer Genome Atlas were included. For each patient, we calculated 348 hand-crafted radiomics features and 8192 deep features generated by a pretrained convolutional neural network. We then applied feature selection and Elastic Net-Cox modeling to differentiate patients into long- and short-term survivors.

RESULTS

In the 50 patients with high-grade gliomas from our institution, the combined feature analysis framework classified the patients into long- and short-term survivor groups with a log-rank test P value < .001. In the 128 patients from The Cancer Genome Atlas, the framework classified patients into long- and short-term survivors with a log-rank test P value of .014. For the mixed cohort of 50 patients from our institution and 58 patients from The Cancer Genome Atlas, it yielded a log-rank test P value of .035.

CONCLUSIONS

A deep learning model combining deep and radiomics features can dichotomize patients with high-grade gliomas into long- and short-term survivors.

Adjuvant bevacizumab for melanoma patients at high risk of recurrence: survival analysis of the AVAST-M trial

Background

Bevacizumab is a recombinant humanised monoclonal antibody to vascular endothelial growth factor shown to improve survival in advanced solid cancers. We evaluated the role of adjuvant bevacizumab in melanoma patients at high risk of recurrence.

Patients and methods

Patients with resected AJCC stage IIB, IIC and III cutaneous melanoma were randomised to receive either adjuvant bevacizumab (7.5 mg/kg i.v. 3 weekly for 1 year) or standard observation. The primary end point was detection of an 8% difference in 5-year overall survival (OS) rate; secondary end points included disease-free interval (DFI) and distant metastasis-free interval (DMFI). Tumour and blood were analysed for prognostic and predictive markers.

Results

Patients (n=1343) recruited between 2007 and 2012 were predominantly stage III (73%), with median age 56 years (range 18–88 years). With 6.4-year median follow-up, 515 (38%) patients had died [254 (38%) bevacizumab; 261 (39%) observation]; 707 (53%) patients had disease recurrence [336 (50%) bevacizumab, 371 (55%) observation]. OS at 5 years was 64% for both groups [hazard ratio (HR) 0.98; 95% confidence interval (CI) 0.82–1.16, P = 0.78). At 5 years, 51% were disease free on bevacizumab versus 45% on observation (HR 0.85; 95% CI 0.74–0.99, P = 0.03), 58% were distant metastasis free on bevacizumab versus 54% on observation (HR 0.91; 95% CI 0.78–1.07, P = 0.25). Forty four percent of 682 melanomas assessed had a BRAF^V600 mutation. In the observation arm, BRAF mutant patients had a trend towards poorer OS compared with BRAF wild-type patients (P = 0.06). BRAF mutation positivity trended towards better OS with bevacizumab (P = 0.21).

Conclusions

Adjuvant bevacizumab after resection of high-risk melanoma improves DFI, but not OS. BRAF mutation status may predict for poorer OS untreated and potential benefit from bevacizumab.

Clinical Trial Information

ISRCTN 81261306; EudraCT Number: 2006-005505-64

Predictive impact of rare genomic copy number variations in siblings of individuals with autism spectrum disorders

Identification of genetic biomarkers associated with autism spectrum disorders (ASDs) could improve recurrence prediction for families with a child with ASD. Here, we describe clinical microarray findings for 253 longitudinally phenotyped ASD families from the Baby Siblings Research Consortium (BSRC), encompassing 288 infant siblings. By age 3, 103 siblings (35.8%) were diagnosed with ASD and 54 (18.8%) were developing atypically. Thirteen siblings have copy number variants (CNVs) involving ASD-relevant genes: 6 with ASD, 5 atypically developing, and 2 typically developing. Within these families, an ASD-related CNV in a sibling has a positive predictive value (PPV) for ASD or atypical development of 0.83; the Simons Simplex Collection of ASD families shows similar PPVs. Polygenic risk analyses suggest that common genetic variants may also contribute to ASD. CNV findings would have been pre-symptomatically predictive of ASD or atypical development in 11 (7%) of the 157 BSRC siblings who were eventually diagnosed clinically.

Multiscale analyses reveal native-like lamellar bone repair and near perfect bone-contact with porous strontium-loaded bioactive glass

The efficient healing of critical-sized bone defects using synthetic biomaterial-based strategies is promising but remains challenging as it requires the development of biomaterials that combine a 3D porous architecture and a robust biological activity. Bioactive glasses (BGs) are attractive candidates as they stimulate a biological response that favors osteogenesis and vascularization, but amorphous 3D porous BGs are difficult to produce because conventional compositions crystallize during processing. Here, we rationally designed a porous, strontium-releasing, bioactive glass-based scaffold (pSrBG) whose composition was tailored to deliver strontium and whose properties were optimized to retain an amorphous phase, induce tissue infiltration and encourage bone formation. The hypothesis was that it would allow the repair of a critical-sized defect in an ovine model with newly-formed bone exhibiting physiological matrix composition and structural architecture. Histological and histomorphometric analyses combined with indentation testing showed pSrBG encouraged near perfect bone-to-material contact and the formation of well-organized lamellar bone. Analysis of bone quality by a combination of Raman spectral imaging, small-angle X-ray scattering, X-ray fluorescence and focused ion beam-scanning electron microscopy demonstrated that the repaired tissue was akin to that of normal, healthy bone, and incorporated small amounts of strontium in the newly formed bone mineral. These data show the potential of pSrBG to induce an efficient repair of critical-sized bone defects and establish the importance of thorough multi-scale characterization in assessing biomaterial outcomes in large animal models.

Design and implementation of a predictive risk model to improve oncology patient management

154

Background: Methods to identify cancer patients that are likely to seek inpatient care for conditions that can be treated in the outpatient setting are not well defined. In light of the rise in value-based care programs, there is increased pressure on oncology providers to decrease costs of care while continuing to achieve high-quality outcomes. One way this can be achieved is by decreasing avoidable, high-cost utilization through population management. We sought to investigate the feasibility of creating a model to predict which patients were more likely to utilize emergency department (ED) and inpatient hospital (IP) services as well as the impact such a model may have on patient management. Methods: For a sample of 1093 patients, historical information was gathered across four domains: Cancer-specific Attributes, Comorbidity Burden, Social Factors, and Utilization History. This data set was then used to design a predictive model which assigned a numerical “acuity” score to each patient. Patients were ranked by numerical score, and their subsequent ED and IP utilization was measured. The developed model was then tested on an independent set of 591 patients to assess broader validity. After development, the predictive model was built into a tool for use in patient management by a team of nurse care managers. Results: Of the 100 highest-ranking patients in the training sample, 29% had at least one future hospitalization and 33% had at least one future ED visit, compared to 13% and 19% in the entire sample, respectively. In the validation sample, 11% of the 100 highest-ranking patients had at least one future hospitalization and 20% had at least one future ED visit, compared to 5% and 13% in the entire sample, respectively. Before model deployment, an average of 39 follow-up touchpoints were completed for high-risk patients per month. In the 6 months after deployment, the average rose to 171 touchpoints per month, an increase of 335%. Conclusions: Models can be developed to proactively identify cancer patients at higher risk of utilizing ED and inpatient hospital services. Implementation of such a model can also increase targeted outreach and communication with patients at greater risk of utilizing high-cost services.

Pharmacokinetic modelling and validation of the half-life extension needed to reduce the burden of infusions compared with standard factor VIII

INTRODUCTION

Currently, no universally accepted definition of extended half-life (EHL) recombinant FVIII (rFVIII) exists. Identifying the minimum half-life extension ratio required for a reduction in dosing frequency compared with standard rFVIII could enable a more practical approach to decisions around prophylaxis with EHL rFVIII.

AIM

To identify the half-life extension ratio required to decrease rFVIII dosing frequency by at least 1 day while maintaining the proportion of patients with plasma rFVIII levels above 1 IU/dL and without increasing the total weekly dose.

METHODS

A previously published population pharmacokinetic model for standard rFVIII was used to estimate the percentage of patients with factor VIII (FVIII) levels always >1 IU/dL using various benchmark regimens. Using modelling, dosing frequency was reduced while rFVIII half-life was extended until the percentage of patients with FVIII >1 IU/dL equalled that of the benchmark regimen.

RESULTS

Benchmark 3×/wk dosing totalling 100 IU/kg/wk of rFVIII resulted in 56.6% of patients with FVIII levels always >1 IU/dL. With 2×/wk dosing, totalling 80 or 90 IU/kg/wk, half-life extensions required to maintain 56.6% of patients at FVIII levels >1 IU/dL were 1.30 and 1.26, respectively. A half-life extension ratio of 1.33 was required to change dosing from every 48 hours to every 72 hours (both at 105 IU/kg/wk) while maintaining 92.8% of patients with FVIII >1 IU/dL.

CONCLUSION

Based on this investigation, EHL rFVIII products should have a minimum half-life extension ratio of 1.3 to provide a reduction in dosing frequency from 3× to 2×/wk compared with standard rFVIII products while maintaining the same minimum FVIII trough level.

Abstract P6-12-02: Racial/ethnic differences in sleep quality and duration among breast cancer survivors: Results from the women's health initiative (WHI)

BACKGROUND: Sleep is a crucial factor for optimal health, but breast cancer survivors often report poor sleep quality. It is estimated 20-70% of survivors have at least one sleep problem, which contribute to quality of life and health differences among survivors. Minority groups tend to have poorer sleep quality and shorter sleep duration than Non-Hispanic Whites (NHW). African-Americans (AA) with breast cancer have a poorer prognosis than NHW for each stage-specific diagnosis and are twice as likely as NHW to report short sleep duration, yet survivor studies are still lacking in AA participants. The purpose of this study was to examine sleep quality and duration patterns before and after cancer diagnosis by race/ethnicity among WHI breast cancer survivors.

METHODS: There were 12,098 postmenopausal women diagnosed with invasive breast cancer after WHI enrollment who were eligible for this secondary analysis. Baseline demographic and clinical characteristics were described. The WHI Insomnia Rating Scale (WHIIRS) was measured at multiple time points pre- and post-diagnosis. A higher WHIIRS scores (0-20 points) indicates greater sleep disturbance and ≥9 points identifies clinical insomnia. A linear mixed model was fit to the WHIIRS sleep quality data to examine if the trend in sleep quality with time changed following a cancer diagnosis. For short (&lt;6hrs) and long (≥9hrs) sleep duration, we fit a logistic regression model with multilevel mixed effects.

RESULTS: The majority of participants were NHW (87.4%), mean age at diagnosis was 70.3 years, and 75% had localized breast cancer at diagnosis. At baseline, 30% of women had insomnia. The lowest average WHIIRS score was 5.6 among Asians, and the highest was 6.6 among American-Indians and NHWs (p=0.02). AAs had the most women sleeping ≤5 hrs/night and NHW had the least (19.6% vs 5.7%, p&lt;0.01). At diagnosis, the average WHIIRS score was 7.2. After diagnosis, sleep quality improved in the overall study population (p=0.03). Short sleep duration ranged from 6% before diagnosis, 9% at diagnosis and 11% after diagnosis (p=0.29). Long sleep duration ranged from 3% before diagnosis, 6% at diagnosis and 15% after diagnosis (p=0.43). There was no difference in sleep quality across race after diagnosis (p=0.53). The probability of short sleep and long sleep after diagnosis did not differ significantly across race (p=0.12, p=0.90), however racial minorities tended to have higher probabilities of short sleep at diagnosis compared to NHWs.

DISCUSSION: Sleep is an appealing area to target for improvement due to the multiple ways it can be treated. With increasing survival rates, there is an emphasis on improving quality of life in survivors. Our results span 20 years pre-diagnosis to 15 years post-diagnosis and are similar to shorter follow-up studies which found most women's sleep problems resolve within a few years of treatment completion. The lack of difference by race was an unexpected finding in another similar longitudinal study, which suggested most differences are seen in cross-sectional sleep studies. This study adds to the literature on longitudinal sleep data, especially to the little data on sleep trajectories in minority breast cancer survivors.

Citation Format: Beverly CM, Naughton M, Foraker R, Pennell M, Young G, Hale L, Crane T, Pan K, Danhauer S, Feliciano E, Paskett E. Racial/ethnic differences in sleep quality and duration among breast cancer survivors: Results from the women's health initiative (WHI) [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P6-12-02.

A Database Built Upon the Medical Event Vector

PHAMIS is an automated medical information system designed to provide long-term storage and retrieval of clinical information about Public Health Service patients. The patient database is composed of clinical events stored in compact format as multidimensional vectors in a write-once, read-only file to minimize file maintenance. Clinical observations are recorded as pointers to a large and expandable dictionary, rather than as text, to reduce storage requirements. The database design includes both within-patient-record and between-patient-recorcl indexes to speed data retrieval and facilitate report generation.

Clinical use of recombinant factor VIII Fc and recombinant factor IX Fc in patients with haemophilia A and B

INTRODUCTION

Although clinical trials have demonstrated extended half-life (EHL) VIII and IX fusion proteins to be safe and efficacious in patients with haemophilia A and B, studies on real-world clinical application have not been performed.

AIM

To retrospectively examine the real-world experience of rFVIII Fc and rFIX Fc in patients.

METHODS

A retrospective review of existing medical records of patients with haemophilia A or haemophilia B who had been prescribed rFVIII Fc or rFIX Fc was conducted from the Children's Hospital Los Angeles Haemostasis and Thrombosis Centre database.

RESULTS

A total of 36 male subjects enroled in the study (17 patients with haemophilia A and 19 patients with haemophilia B; 0-18 years of age, N = 27; >18 years of age, N = 9). Patients had a reduction of their ABR and AJBR following initiation of EHL factors. For patients with haemophilia A, the ABR and ABJR fell from 2.3 and 1.8 to 1.3 and 0.71, respectively. For patients with haemophilia B, the ABR and ABJR fell from 2.5 and 2.1 to 0.82 and 0.37, respectively. Five of 36 patients reverted from EHL back to standard half-life (SHL) factor treatment. Overall, treatment with EHL factors reduced factor consumption by nearly half compared to treatment with SHL factors in patients with haemophilia B.

CONCLUSION

This study demonstrates the largely successful transition of 36 patients from SHL to EHL factor products.

Target plasma factor levels for personalized treatment in haemophilia: a Delphi consensus statement

BACKGROUND

Prophylactic replacement with factor concentrate is the optimal treatment for persons with severe haemophilia to avoid or minimize bleeding. This ultimately prevents or reduces joint disease and improves life expectancy and quality of life towards values matching those in the normal population. However, uncertainty still exists around the optimal regimens to be prescribed for prophylaxis. An increasing number of treating physicians and patients are showing interest in patient-tailored approaches to prophylaxis, which aim to harmonize the prophylaxis regimen with the patients' bleeding phenotype, levels of physical activity and a variety of other variables.

METHODS

A modified Delphi technique was adopted to generate consensus. The expert panel met in person to set the objectives, be trained on the Delphi technique and agree on the desired level of consensus. Three iterations were used to identify the targets, the scenarios and their combinations.

RESULTS

Twenty-eight scenarios and eight target levels were identified and used to issue recommendations. The panel reached the desired level of consensus on positive or negative recommendations. Areas where consensus was not reached were identified and proposed as areas for future research. Prospective assessment of the validity of most of the proposed targets is recommended.

CONCLUSIONS

We have generated, by expert consensus, target plasma levels of factor concentrate to be used to tailor treatment for persons with haemophilia.