Model-based meta-analysis using latent variable modeling to set benchmarks for new treatments of systemic lupus erythematosus

Several investigational agents are under evaluation in systemic lupus erythematosus (SLE) clinical trials but quantitative frameworks to enable comparison of their efficacy to reference benchmark treatments are lacking. To benchmark SLE treatment effects and identify clinically important covariates, we developed a model-based meta-analysis (MBMA) within a latent variable model framework for efficacy end points and SLE composite end point scores (BILAG-based Composite Lupus Assessment and Systemic Lupus Erythematosus Responder Index) using aggregate-level data on approved and investigational therapeutics. SLE trials were searched using PubMed and www.clinicaltrials.gov for treatment name, SLE and clinical trial as search criteria that resulted in four data structures: (1) study and investigational agent, (2) dose and regimen, (3) baseline descriptors, and (4) outcomes. The final dataset consisted of 25 studies and 81 treatment arms evaluating 16 different agents. A previously developed (K Goteti et al. 2022) SLE latent variable model of data from placebo arms (placebo + standard of care treatments) was used to describe aggregate SLE end points over time for the various SLE placebo and treatment arms in a Bayesian MBMA framework. Continuous dose-effect relationships using a maximum effect model were included for anifrolumab, belimumab, CC-220 (iberdomide), epratuzumab, lulizumab pegol, and sifalimumab, whereas the remaining treatments were modeled as discrete dose effects. The final MBMA model was then used to benchmark these compounds with respect to the maximal efficacy on the latent variable compared to the placebo. This MBMA illustrates the application of latent variable models in understanding the trajectories of composite end points in chronic diseases and should enable model-informed development of new investigational agents in SLE.

Bayesian estimation in NONMEM

Bayesian estimation is a powerful but underutilized tool for answering drug development questions. In this tutorial, the principles of Bayesian model development, assessment, and prior selection will be outlined. An example pharmacokinetic (PK) model will be used to demonstrate the implementation of Bayesian modeling using the nonlinear mixed-effects modeling software NONMEM.

Harmonization of criteria and terminology in fetal rat skeletal evaluations

BACKGROUND

A survey of laboratories in North American and Europe that routinely conduct fetal skeletal examinations was performed with the purpose of (1) understanding current terminology used for classifying skeletal findings in developmental toxicity (DT) studies and (2) understanding the criteria used to identify relatively common findings that sufficiently deviate from normal. The goal was to promote terminology harmonization and improve interlaboratory consistency in the criteria used to identify developmental anomalies.

METHODS

The survey, designed based on terminology for developmental anomalies recommended by an international collaboration (Makris et al., Congenital Anomalies, 2009;49(3):123-246), was conducted by a subgroup (authors of this publication) of the Royal Society of Biology's International Register of Fetal Morphologists (IRFM).

RESULTS

Individual and summarized anonymized responses are provided here. The authors, who are expert fetal morphologists with experience performing fetal examinations, reviewed the responses and generated recommendations on preferred terminology and criteria for determining when morphological variations deviate from normal and warrant recording of the findings for skeletal observations in Sprague Dawley (SD) fetal rats. The objective of these recommendations is to complement Makris et al. (Congenital Anomalies, 2009;49(3):123-246).

CONCLUSION

The broad application will improve interlaboratory harmonization of recording fetal skeleton findings in developmental toxicity studies intended for regulatory submissions, including SEND (Standard for Exchange of Nonclinical Data).

Work-related injuries and attendance at a Canadian regional emergency department

BACKGROUND

Monitoring trends in the burden of illness and injury attributable to work is key in assessing occupational health hazards; however, New Brunswick does not participate in the Canadian National Ambulatory Care Reporting System which itself does not collect details of occupation and industry.

AIMS

We set out to determine the proportion of emergency department attendances that were attributable to a work-related cause. We also wanted to evaluate the recording of occupation in the electronic health record system, and to describe the characteristics of patients with a work-related presentation.

METHODS

A retrospective observational study over a 1-year period was conducted using an administrative database obtained from Canadian Emergency Department Information System. Descriptive statistics are used to present the analysis of categorical and continuous data.

RESULTS

A total of 49 365 patients were included for analysis. Two per cent of patients presented with a self-reported work-related condition. Health care and social assistance, construction, retail trade and manufacturing were the most common industries reported by patients.

CONCLUSIONS

This study found the rate of work-related medical conditions to be substantially less than expected, and that occupation was not captured for any patients presenting to the emergency department with a work-related condition, despite a field being available in the electronic health record registration system. We were able to analyse the industry sectors for work-related presentations. The recording and coding of occupation and industry would significantly benefit occupational epidemiology in emergency medicine as well as potentially improving patient outcomes and health system efficiencies.

Impact of Drug Exposure on Resistance Selection Following Artemether-Lumefantrine Treatment for Malaria in Children With and Without HIV in Uganda

Artemisinin-based combination therapies (ACTs) are the primary treatment for malaria. It is essential to characterize the pharmacokinetics (PKs) and pharmacodynamics (PDs) of ACTs in vulnerable populations at risk of suboptimal dosing. We developed a population PK/PD model using data from our previous study of artemether-lumefantrine in HIV-uninfected and HIV-infected children living in a high-transmission region of Uganda. HIV-infected children were on efavirenz-, nevirapine-, or lopinavir-ritonavir-based antiretroviral regimens, with daily trimethoprim-sulfamethoxazole prophylaxis. We assessed selection for resistance in two key parasite transporters, pfcrt and pfmdr1, over 42-day follow-up and incorporated genotyping into a time-to-event model to ascertain how resistance genotype in relation to drug exposure impacts recurrence risk. Two hundred seventy-seven children contributed 364 episodes to the model (186 HIV-uninfected and 178 HIV-infected), with recurrent microscopy-detectable parasitemia detected in 176 episodes by day 42. The final model was a two-compartment model with first-order absorption and an estimated age effect on bioavailability. Systemic lumefantrine exposure was highest with lopinavir-ritonavir, lowest with efavirenz, and equivalent with nevirapine and HIV-uninfected children. HIV status and lumefantrine concentration were significant factors associated with recurrence risk. Significant selection was demonstrated for pfmdr1 N86 and pfcrt K76 in recurrent infections, with no evidence of selection for pfmdr1 Y184F. Less sensitive parasites were able to tolerate lumefantrine concentrations ~ 3.5-fold higher than more sensitive parasites. This is the first population PK model of lumefantrine in HIV-infected children and demonstrates selection for reduced lumefantrine susceptibility, a concern as we confront the threat to ACTs posed by emerging artemisinin resistance in Africa.

Variable or variate? A conundrum in pharmacometrics exposure-response models

Key elements of scientific writing-consistency and clarity-can be compromised in case of inaccurate use of methodological terms, especially in complex and multidisciplinary scientific fields. Such is the case in reports of pharmacometrics exposure-response analyses with the use of the terms univariate/multivariate and univariable/multivariable. This perspective outlines the issues in the use of these terms, clarifies their definitions, provides examples, and makes recommendations for authors, reviewers, and journals in the fields of clinical pharmacology and pharmacometrics.

Distal biceps repair through a single incision with the use of a knotless cortical button device: Mid-term results

Background

Distal biceps rupture presents with an increasing incidence and evidence suggests that although a surgical repair is not mandatory, it results in superior functional outcomes when compared to non-operative management. As implant technology has advanced, several devices have been utilised and studied in managing this pathology. We present our single-centre experience with the use of the ToggleLoc Ziploop reattachment device, a knotless cortical button implant, using a single-incision technique.

Methods

Retrospective series of 70 consecutive distal biceps tendon repairs, at a mean follow-up of 45.6 months after surgery, using a standardised single implant, single-incision technique, and post-operative rehabilitation programme.

Results

There was one (1.4%) re-rupture in our patient cohort. The range of motion was complete in all patients except for one patient who had symptomatic heterotopic ossification, causing limitation in pronation. Complications were minor with the commonest being transient neuropraxia of the lateral cutaneous nerve of the forearm. The mean Oxford elbow score was 46.9 out of 48, and the patient global impression of change scale was 7 out of 7 in 77% of cases.

Conclusion

Our data support this technique and implant combination when dealing with acute and chronic distal biceps tendon rupture.

Disease trajectory of SLE clinical endpoints and covariates affecting disease severity and probability of response: Analysis of pooled patient-level placebo (Standard-of-Care) data to enable model-informed drug development

Systemic lupus erythematosus (SLE) is an autoimmune disease affecting multiple organ systems. Many investigational agents have failed or shown only modest effects when added to standard of care (SoC) therapy in placebo-controlled trials, and only two therapies have been approved for SLE in the last 60 years. Clinical trial outcomes have shown discordance in drug effects between clinical endpoints. Herein, we characterized longitudinal disease activity in the SLE population and the sources of variability by developing a latent disease trajectory model for SLE component endpoints (Systemic Lupus Erythematosus Disease Activity Index [SLEDAI], Physician's Global Assessment [PGA], British Isles Lupus Assessment Group Index [BILAG]) and composite endpoints (Systemic Lupus Erythematosus Responder Index [SRI], BILAG-based Composite Lupus Assessment [BICLA], and Lupus Low Disease Activity State [LLDAS]) using patient-level historical SoC data from nine phase II and III studies. Across all endpoints, in predictions up to 52 weeks from the final disease trajectory model, the following baseline covariates were associated with a greater decrease in SLE disease activity and higher response to placebo + SoC: Hispanic ethnicity from Central/South America, absence of hypocomplementemia, recent SLE diagnosis, and high baseline disease activity score using SLEDAI and BILAG separately. No discernible differences were observed in the trajectory of response to placebo + SoC across different SoC medications (antimalarial and immunosuppressant such as mycophenolate, methotrexate, and azathioprine). Across all endpoints, disease trajectory showed no difference in Asian versus non-Asian patients, supporting Asia-inclusive global SLE drug development. These results describe the first population approach to support a model-informed drug development framework in SLE.

A-29 Consistency of Clinical Profiles Across Repeat Concussions

Purpose: To evaluate the association between concussion profiles within individual patients across repeat concussions. Methods: Retrospective chart review of 100 adolescents (57.3% male) aged 10–21 years presenting to a concussion clinic within 30 days of injury for two separate injuries between 2011 and 2021. Clinicians conducted multidomain assessments including vestibular/ocular motor screening, neurocognitive testing, symptoms and medical/injury history to adjudicate the following concussion clinical profiles: vestibular, ocular, post-traumatic migraine, cognitive fatigue, and anxiety/mood. Chi-square tests with odds ratios (OR) and 95% confidence intervals (CI) were conducted to examine the association of each profile from the first to the second concussion. Results: Chi-square analyses supported associations between the first and second concussions (time between injuries = 667.1 ± 529.2 days) for the vestibular (χ2 = 10.08, p < 0.01, OR = 3.75, 95% CI = 1.63–8.62), ocular (χ2 = 6.51, p < 0.05, OR = 3.51, 95% CI = 1.30–9.46), and migraine (χ2 = 11.056, p < 0.001, OR = 4.01, 95% CI = 1.73–9.29) profiles, such that having that profile at first concussion was associated with increased likelihood of having the same profile at second concussion. Chi-square analyses for cognitive fatigue and anxiety/mood were not significant. Conclusions: Vestibular, ocular, and migraine profiles at first injury predicted their presence at second injury, which may reflect consistent underlying risk factors (e.g., sex migraine history) for these profiles. Conversely, no association was supported for anxiety/mood and cognitive fatigue profiles across injuries. The present findings are the first to demonstrate that certain profiles are likely to recur after repeat concussion. This information can be used by clinicians to inform earlier, targeted treatment recommendations for associated profiles.

IMPACT-Global Hip Fracture Audit: Nosocomial infection, risk prediction and prognostication, minimum reporting standards and global collaborative audit. Lessons from an international multicentre study of 7,090 patients conducted in 14 nations during the COVID-19 pandemic

Aims

This international study aimed to assess: 1) the prevalence of preoperative and postoperative COVID-19 among patients with hip fracture, 2) the effect on 30-day mortality, and 3) clinical factors associated with the infection and with mortality in COVID-19-positive patients.

Methods

A multicentre collaboration among 112 centres in 14 countries collected data on all patients presenting with a hip fracture between 1st March-31st May 2020. Demographics, residence, place of injury, presentation blood tests, Nottingham Hip Fracture Score, time to surgery, management, ASA grade, length of stay, COVID-19 and 30-day mortality status were recorded.

Results

A total of 7090 patients were included, with a mean age of 82.2 (range 50–104) years and 4959 (69.9%) being female. Of 651 (9.2%) patients diagnosed with COVID-19, 225 (34.6%) were positive at presentation and 426 (65.4%) were positive postoperatively. Positive COVID-19 status was independently associated with male sex (odds ratio (OR) 1.38, p = 0.001), residential care (OR 2.15, p < 0.001), inpatient fall (OR 2.23, p = 0.003), cancer (OR 0.63, p = 0.009), ASA grades 4 (OR 1.59, p = 0.008) or 5 (OR 8.28, p < 0.001), and longer admission (OR 1.06 for each increasing day, p < 0.001). Patients with COVID-19 at any time had a significantly lower chance of 30-day survival versus those without COVID-19 (72.7% versus 92.6%, p < 0.001). COVID-19 was independently associated with an increased 30-day mortality risk (hazard ratio (HR) 2.83, p < 0.001). Increasing age (HR 1.03, p = 0.028), male sex (HR 2.35, p < 0.001), renal disease (HR 1.53, p = 0.017), and pulmonary disease (HR 1.45, p = 0.039) were independently associated with a higher 30-day mortality risk in patients with COVID-19 when adjusting for confounders.

Conclusion

The prevalence of COVID-19 in hip fracture patients during the first wave of the pandemic was 9%, and was independently associated with a three-fold increased 30-day mortality risk. Among COVID-19-positive patients, those who were older, male, with renal or pulmonary disease had a significantly higher 30-day mortality risk.

Pharmacometric modeling and machine learning analyses of prognostic and predictive factors in the JAVELIN Gastric 100 phase III trial of avelumab

Avelumab (anti–PD‐L1) is an approved anticancer treatment for several indications. The JAVELIN Gastric 100 phase III trial did not meet its primary objective of demonstrating superior overall survival (OS) with avelumab maintenance versus continued chemotherapy in patients with advanced gastric cancer/gastroesophageal junction cancer; however, the OS rate was numerically higher with avelumab at timepoints after 12 months. Machine learning (random forests, SIDEScreen, and variable‐importance assessments) was used to build models to identify prognostic/predictive factors associated with long‐term OS and tumor growth dynamics (TGDs). Baseline, re‐baseline, and longitudinal variables were evaluated as covariates in a parametric time‐to‐event model for OS and Gompertzian population model for TGD. The final OS model incorporated a treatment effect on the log‐logistic shape parameter but did not identify a treatment effect on OS or TGD. Variables identified as prognostic for longer OS included older age; higher gamma‐glutamyl transferase (GGT) or albumin; absence of peritoneal carcinomatosis; lower neutrophil‐lymphocyte ratio, lactate dehydrogenase, or C‐reactive protein (CRP); response to induction chemotherapy; and Eastern Cooperative Oncology Group performance status of 0. Among baseline and time‐varying covariates, the largest effects were found for GGT and CRP, respectively. Liver metastasis at re‐baseline predicted higher tumor growth. Tumor size after induction chemotherapy was associated with number of metastatic sites and stable disease (vs. response). Asian region did not impact OS or TGD. Overall, an innovative workflow supporting pharmacometric modeling of OS and TGD was established. Consistent with the primary trial analysis, no treatment effect was identified. However, potential prognostic factors were identified.

Intravascular lithotripsy during percutaneous coronary intervention for calcified coronary lesions: analysis of patient and procedural characteristics and clinical outcomes

Funding Acknowledgements

Type of funding sources: None.

Background/Introduction

Coronary artery calcification is frequently encountered during percutaneous coronary intervention (PCI). It can reduce PCI success and increase intra-procedural and post-procedural complications, including stent embolization, under-expansion and mal-apposition. Intravascular lithotripsy (IVL) is a new tool developed to treat calcified coronary lesions.

Purpose

Retrospective analysis of all cases of intravascular lithotripsy performed within our local health district to examine patient and procedural characteristics and clinical outcomes.

Methods

All patients undergoing PCI with intravascular lithotripsy between September 2019-August 2021 within our local health district were analysed. Patient and procedural characteristics and clinical outcomes were recorded.

Results

67 patients (50 men) were included with mean age 71.4 ± 8.7years. Risk factors prevalence included smoking (34%), hypertension (82%), dyslipidaemia (69%) and diabetes (46%). Trans-radial artery access was used in 38 patients (57%). IVL was performed most commonly in the left anterior descending artery (52%),[Figure 1]. IVL was utilised in 9 chronic total occlusions and 12 bifurcation lesions. Intracoronary (IC) imaging was performed in 59 patients (88%), intravascular ultrasound in 41(61%) and optical coherence tomography in 18 (27%). 41 (69%) patients had imaging performed pre and post IVL and post PCI.  IC imaging identified 14 cases with 270º calcification arc and 45 cases with 360º arc. Nine cases (13.4%) required rotational atherectomy prior to IVL (most commonly 1.75mm burr). Mean reference vessel diameter was 3.2 ± 0.3mm. Mean lesion length was 36.3 ± 16.5mm. Mean pre-PCI stenosis was 85.5 ± 10.8%. Drug eluting stents were successfully deployed in 57 cases (85%), 10 had balloon angioplasty alone. Mean stent length was 39.2 ± 17.8mm. Mean post-PCI stenosis was 4.5 ± 13.3% (median 0%). Figure 2 shows a statistically significant increase in minimum lumen diameter and minimum lumen area post-IVL and minimal-stent-area (MSA) post-PCI. Mean stent expansion was 83%. Mean screening time 35.8 ± 17.8 minutes with mean contrast used 207.3 ± 78.7mL. No sustained arrhythmias or side-branch loss occurred. Vessel rupture was recorded in one patient necessitating urgent cardiac surgery (due to oversized balloon) and in 4 cases the IVL balloon could not cross the lesion.

Conclusion

Our experience shows that IVL is safe and effective and facilitates stent delivery and expansion. Intracoronary imaging is important to determine the need for calcium modification and evaluate its success prior to stent delivery and to confirm optimised stent expansion. Abstract Figure. Breakdown of PCI Artery  Abstract Figure. IC Dimensions Pre/Post IVL/Post PCI

A model-based analysis to guide gonadotropin-releasing hormone receptor antagonist use for management of endometriosis

Aims

To identify linzagolix doses, an oral GnRH receptor antagonist, that effectively lower oestradiol (E2) to relieve endometriosis‐related pelvic pain without compromising bone health.

Methods

Integrated statistical, pharmacokinetic–pharmacodynamic and systems pharmacology models were developed from Phase 1 and 2 clinical trial data in healthy volunteers and patients, receiving linzagolix 25–200 mg daily or placebo, and analysed simultaneously. The main outcome measures were pelvic pain scores for dysmenorrhoea, nonmenstrual pelvic pain (NMPP), uterine bleeding and lumbar spine bone mineral density (BMD).

Results

Linzagolix pharmacokinetics were described by a 2‐compartment model with sequential zero/first‐order absorption process (CL/F: 0.422 L/h). E2 changes over time were well described as a function of linzagolix 24‐hour AUC (AUC₅₀: 1.68 × 10⁵ ng h/mL). For a Caucasian reference patient, a change in E2 from 50–20 pg/mL at 24 weeks increased the odds of relief of dysmenorrhoea 1.33‐fold and NMPP 1.07‐fold (95% CI: 1.22–1.47 and 1.02–1.12, respectively) and decreased bleeding days by 1.55 (95% CI: 1.39–1.72). A previously validated quantitative systems pharmacology BMD model was adjusted to the clinical data. The mean week 24 lumbar spine BMD change from baseline ranged from −0.092% in the 50 mg dose, −1.30% in the 100 mg dose group and −2.67% in the 200 mg dose group.

Discussion

The previously‐reported E2 target range (20–50 pg/mL) to balance efficacy and safety endpoints was confirmed. Linzagolix once daily doses between 75–125 mg daily were expected to meet endometriosis‐associated pain, efficacy, and BMD loss targets in Caucasian patients.

Exposure-response analysis of efficacy and safety for pexidartinib in patients with tenosynovial giant cell tumor

This analysis was conducted to assess exposure–response relationships for efficacy and safety of pexidartinib in patients with tenosynovial giant cell tumor. Efficacy was assessed categorically by overall response rate (ORR) with Response Evaluation Criteria in Solid Tumors version 1.1 and longitudinally (changes in tumor size and volume). Safety included hepatic parameters (i.e., alanine aminotransferase [ALT], aspartate aminotransferase [AST], and total bilirubin). Average pexidartinib concentration (C_avg) was identified as the primary exposure parameter correlated with response. In categorical and longitudinal analyses, higher C_avg coincided with greater ORR and tumor size reduction, respectively, with smaller joint size having a greater impact. For safety, a significant relationship was observed between C_avg and incidence of ALT‐related and AST‐related adverse events (AEs). With increased exposure, an increase in efficacy was predicted with near maximum effect at 800 mg/day. Higher initial dose (1000 mg/day) during the first 2 weeks did not improve efficacy. Higher doses were associated with an increased risk of ALT‐related and AST‐related AEs. These results support the US Food and Drug Administration–approved dose (400 mg two times/day without initial loading dose).

Impact of cardiac rehabilitation on 3 year outcomes amongst patients after acute coronary syndrome: (ACS) SNAPSHOT ACS follow-up study

Background

Cardiovascular disease is the leading cause of disease burden globally. With advancements in medical and surgical care more people are surviving initial acute coronary syndrome (ACS) and are in need of secondary prevention and cardiac rehabilitation (CR). Increasing availability of high quality individual-level data linkage provides robust estimates of outcomes long-term.

Purpose

To compare 3 year outcomes amongst ACS survivors who did and did not participate in Australian CR programs.

Methods

SNAPSHOT ACS follow-up study included 1806 patients admitted to 232 hospitals who were followed-up by data linkage (cross-jurisdictional morbidity, national death index, Pharmaceutical Benefit Schedule) at 6 and 36 months to compare those who did/not attend CR.

Results

In total, the cohort had a mean age of 65.8 (13.4) years, 60% were male, only 25% (461/1806) attended CR. During index admission, attendees were more likely to have had PCI (39% v 14%, p&lt;0.001), CABG (11% v 2%, p&lt;0.001) and a diagnosis of STEMI (21% v 5%, p&lt;0.001) than those who did not attend. However, there was no significant difference between CR attendees/non-attendees for risk factors (LDL-cholesterol, smoking, obesity). Only 19% of eligible women attended CR compared to 30% of men (p&lt;0.001). At 36 months, there were fewer deaths amongst CR attendees (19/461, 4.1%) than non-attendees (116/1345, 8.6%) (p=0.001). CR attendees were more likely to have repeat ACS, PCI, CABG at both 6 and 36 months (Table). At 36 months, CR attendees were more likely to have been prescribed antiplatelets (78% v 53%, p&lt;0.001), statins (91% 73%, p&lt;0.001), beta-blockers (11% v 13%, p=0.002) and ACEI/ARBs (72% v 61%, p&lt;0.001) than non-attendees.

Conclusions

Amongst Australian ACS survivors, participation in CR was associated with less likelihood of death and increased prescription of pharmacotherapy. However, attendance at CR was associated with higher rates of repeat ACS and revascularisation.

Funding Acknowledgement

Type of funding source: Foundation. Main funding source(s): New South Wales Cardiovascular Research Network, National Heart Foundation

The impact of socioeconomic status on secondary prevention of the acute coronary syndrome

Background

Although socioeconomic status (SES) has been reported to be associated with health inequities, there are limited studies exploring the association between SES and secondary prevention of acute coronary syndrome (ACS) in countries with universal health cover.

Purpose

The aim is to examine whether SES has an impact on the secondary prevention of ACS in Australia.

Methods

Australian SNAPSHOT ACS data (2012) and its 18-month follow-up data were linked to admissions data from 6 jurisdictions covering all states and territories, national death index and Medicare Pharmaceutical Benefits Scheme data covering up to 3 years post-discharge. The five SES groups (lowest in Group 1 and highest in Group 5) were derived from the Australian Bureau of Statistics Socio-Economic Indexes for Areas (SEIFA) using the residential postcode at baseline. Outcomes were cardiac rehabilitation (CR) participation and smoking rate at 18 months post discharge as well as the use of ≥3 of the 4 indicated medications, all-cause death and cardiovascular disease (CVD) rates by 36 months of discharge. Outcomes were compared between the groups using the multilevel logistic regression with covariates of SES (5 groups), sex, GRACE risk score (4 groups), ACS diagnosis (STEMI/NSTEMI/UA) and the jurisdictions where the admissions data were linked.

Results

Of 1655 patients with ACS (mean age 68±13.5 yrs, 65% were male), who were discharged from hospital alive and had linked data available, 353 (21%) were in SES Group 1 (lowest SES), 369 (22%) in Group 2, 382 (23%) in Group 3, 296 (18%) in Group 4 and 255 (15%) in Group 5 (highest SES). Baseline clinical characteristics were comparable across the five SES groups. At 18-month after discharge, 1014 (61%) patients were followed-up with comparable loss to follow-up in each group. After adjustment, fewer patients in the lower SES groups (Groups 1 and 2) had participated in CR than those in the highest SES group (Group 5) (OR (95% CI): 0.60 (0.36, 0.99) and 0.56 (0.35, 0.91), respectively). Moreover, the odds of smoking was greater in Group 3 than Group 5 (2.60 (1.15, 5.89)) but no trend was found across the groups. By 36 months of discharge after adjustment, there was no difference in the odds of using ≥3 out of 4 medications between the SES groups. Despite this, patients in Groups 1 and 2 were significantly more likely to die than those in the highest SES group (1.96 (1.19, 3.21) and 1.91 (1.19, 3.07), respectively). The odds of CVD readmission did not differ across SES groups.

Conclusion

This study suggests that patients with low SES were less likely to participate in CR programs and more likely to die than those with high SES. Smoking rates varied between patients with intermediate and high SES but no trend was found across the groups. Despite the universal health cover available, inequity between the SES groups still exist. Future research is needed to further explore strategies to help close the evidence-practice gaps.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): Australian National Heart Foundation Postdoctoral Fellowship

A-40 Predictors of Failed Effort Testing at Initial Clinic Visit for Concussion Rehabilitation and Outcomes

Objective

Neuropsychological evaluation of concussion typically includes performance validity testing to assess effort. The aim of this study was to explore the usefulness of effort testing as part of initial screening for concussion rehabilitation, including determining the factors that predict effort testing and evaluate outcomes between “good effort” and “failed effort” groups.

Method

Records of 76 patients aged 16–66 years old (M = 40.58 years, SD = 14.18) seen for rehabilitation of non-sport concussion from 2018–2019 were reviewed. Patients completed clinical interview, neurocognitive screening (ImPACT), effort testing (Word Memory Test), vestibular/oculomotor screening (VOMS), and the post-concussion symptom scale (PCSS). A logistic regression (LR) was conducted to predict effort, with predictors including mental health history, secondary gain, work injury, days post-injury, and PCSS. A series of one-way ANOVAs evaluated outcomes from concussion rehabilitation between the good and failed effort groups.

Results

Failed effort occurred in 42% of cases. The LR accurately classified 81.8% of individuals, with mental health history (p = .01) and PCSS (p = .02) as the only significant predictors of effort. There were no differences in recovery time (p = .56) between effort groups, but the failed effort group took longer to return to work (p = .03). Half of individuals who failed effort were seen until discharge, and 69% of them reported no symptoms/mild symptoms at discharge.

Conclusions

Failure of effort testing was predicted by a history of mental health and high symptom burden. Individuals who fail effort testing at initial visit for concussion rehabilitation take longer to return to functional activity but are capable of achieving recovery with compliance and appropriate rehabilitation.

Association of Time Since Injury to the First Clinic Visit With Recovery Following Concussion

Importance

Recovery after concussion varies, with adolescents taking longer (approximately 30 days) than adults. Many factors have been reported to influence recovery, including preinjury factors, perceptions about recovery, comorbid conditions, and sex. However, 1 factor that may play a role in recovery but has received little attention from researchers is the timeliness of clinical evaluation and care.

Objective

To investigate the association of time since injury with initiation of clinical care on recovery time following concussion.

Design, Setting, and Participants

This retrospective, cross-sectional study was conducted in a sports medicine clinic between August 2016 and March 2018. Eligible participants were aged 12 to 22 years and had a diagnosed, symptomatic concussion; patients were excluded if recovery data were incomplete. Participants were divided into 2 groups: those seen within 7 days of the injury (early) vs between 8 and 20 days of the injury (late). Data were analyzed between June 2019 and August 2019.

Exposures

Time from injury (concussion) to initiation of clinical care.

Main Outcomes and Measures

Recovery time; testing with the Post-Concussion Symptom Scale, Immediate Post-Concussion Assessment and Cognitive Testing, and Vestibular/Ocular Motor Screening instruments; demographic factors, medical history, and injury information.

Results

A total of 416 individuals were eligible, and 254 (61.1%) were excluded, leaving 162 (38.9%) in analyses. The early group (98 patients) and late group (64 patients) did not differ in age (mean [SD] age, early, 15.3 [1.6] years; late, 15.4 [1.6] years), number of female patients (early, 51 of 98 [52.0%]; late, 40 of 64 [62.5%]), or other demographic, medical history, or injury information. The groups also were similar on symptom severity, cognitive, ocular, and vestibular outcomes at the first clinic visit. Results from a logistical regression supported being in the late group (adjusted odds ratio, 5.8 [95% CI, 1.9-17.6]; P = .001) and visual motion sensitivity symptoms greater than 2 (adjusted odds ratio, 4.5 [95% CI, 1.1-18.0]; P = .04) as factors significantly associated with recovery time.

Conclusions and Relevance

Findings suggest that earlier initiation of clinical care is associated with faster recovery after concussion. Other factors may also influence recovery time. Further research is needed to determine the role of active rehabilitation and treatment strategies, as well as demographic factors, medical history, and injury characteristics on the current findings.

Managing the multiply injured patient: the impact of multidisciplinary teams

Management of trauma has been tackled at a national level to improve patient care and mortality. Decision making through a multidisciplinary team approach has resulted in improved patient outcomes through a complex combination of changes. While the focus of trauma care delivery has been towards establishing an effective multidisciplinary trauma service, there are still improvements which can be made. This article reviews the history of trauma care in the UK, and the impact that multidisciplinary teams have had on the management of the multiply injured patient.

Concussion Clinical Profiles Screening (CP Screen) Tool: Preliminary Evidence to Inform a Multidisciplinary Approach

BACKGROUND

Current concussion symptom inventories emphasize total number or symptoms and severity and overlap with other conditions, such as mental health disorders, which may limit their specificity and clinical utility.

OBJECTIVE

To develop and test the reliability and validity of a new Concussion Clinical Profiles Screening tool (CP Screen) in both healthy controls and concussed.

METHODS

CP Screen is a 29-item self-report, clinical profile-based symptom inventory that measures the following 5 concussion clinical profiles: 1) anxiety/mood, 2) cognitive/fatigue, 3) migraine, 4) ocular, and 5) vestibular; and the following 2 modifying factors: 1) sleep and 2) neck. Post-Concussion Symptom Scale (PCSS), vestibular/ocular motor screening (VOMS) tool, and Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) were conducted. CP Screen was administered in community a concussion surveillance program and 2 sports medicine concussion clinics. Responses include 248 athletes, 121 concussed, and 127 controls, enrolled between 2018 and 2019.

RESULTS

Internal consistency of the CP Screen in the control (Cronbach's alpha = .87) and concussed (Cronbach's alpha = .93) samples was high. Moderate to high correlations among the CP Screen factors and PCSS factors and VOMS items, supporting concurrent validity. ROC curve analysis for identifying concussed from controls was significant (P &lt; .001) for all CP Screen factor and modifier scores with excellent AUCs for migraine (.93), ocular (.88), vestibular (.85), and cognitive (.81) factors, demonstrating predictive validity.

CONCLUSION

The CP Screen demonstrated strong reliability, concurrent validity with commonly used concussion assessment (ie, PCSS, VOMS, and ImPACT), and predictive validity for identifying concussion. The CP Screen extends current symptom inventories by evaluating more specific symptoms that may reflect clinical profiles and inform better clinical care.

Influence of Test Environment, Age, Sex, and Sport on Baseline Computerized Neurocognitive Test Performance

BACKGROUND

Baseline computerized testing is a common component of concussion assessments, and the testing environment has been suggested to influence test performance and validity.

PURPOSE

To compare concussion baseline computerized neurocognitive test performance and validity among adolescent athletes based on testing environment (group, individual), age group (10-12, 13-15, 16-18 years), sex (male, female), and sport type (collision/combat, contact, noncontact).

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Through a concussion community outreach program, participants completed baseline computerized neurocognitive testing using Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT). A total of 2845 athletes aged 10 to 18 years completed the baseline assessment. A total of 2241 (79%) athletes completed baseline testing in a group environment, and 604 (21%) completed testing in an individual environment. A random subsample of 500 athletes from each group was selected for statistical comparison.

RESULTS

No significant differences were supported in baseline computerized neurocognitive test performance between the group and individual administration environments. Test validity was statistically similar across testing environment, age group, and sex. However, patients of older age (16-18 years), female sex, and collision/combat and contact sports performed better on ImPACT. There were differences in total symptom severity scores (t = 2.19, df = 998, P = .03), with participants in the group testing environment reporting lower total symptom severity scores than those in the individual testing environment. The rates of invalid tests were low across all age groups, averaging from 4.0% in the 10- to 12-year age group to 4.8% in the 13- to 15-year age group.

CONCLUSION

The findings indicated that concussion baseline neurocognitive test performance is similar when administered in group and individual testing environments. However, differences based on age group, sex, and sport type should be considered when interpreting baseline computerized neurocognitive test scores. The finding of higher symptom scores in older adolescents in the individual testing environment suggests that they may be less forthcoming about symptoms in a group setting.

4938Left ventricular global longitudinal strain recovery predicts scar size reduction and systolic remodelling post ST-elevation myocardial infarction

Background

Left ventricular (LV) strain has prognostic utility following ST-elevation myocardial infarction (STEMI); however, serial changes in LV strain has not been evaluated post-infarct. We sought to determine the relationship between post-STEMI transthoracic echocardiographic (TTE) LV global longitudinal strain (GLS) and cardiac magnetic resonance (CMR) imaging derived scar size and LV systolic remodelling.

Methods

Following revascularisation, 172 first STEMI patients (85% male, 56.9±10.7 years) had paired TTE for GLS, and CMR to evaluate scar size and LV systolic function at baseline (2–7 days) and follow-up (8–10 weeks). Patients were divided into 3 groups according to absolute baseline GLS: group 1 (GLS ≥16%), group 2 (12%< GLS <16%), group 3 (GLS ≤12%). GLS recovery was defined as ≥10% increase in GLS at follow-up, excluding patients with normal baseline GLS. LV systolic adverse remodelling was defined as ≥15% increase in LVESV. LV systolic reverse remodelling was defined as ≥15% decrease in LVESV. Scar reduction was defined as ≥30% decrease in scar size.

Results

Group 1 and 2 had smaller follow-up scar size and higher LVEF compared to group 3 (p<0.0001 for both, see table). There was no difference in scar size reduction or systolic reverse remodeling among the baseline GLS groups (p>0.05 for both). Importantly, no patients from group 1 demonstrated systolic adverse remodelling. Relative change in GLS is significantly correlated with changes in LVEF (r=0.354, p<0.0001) and scar size (r=−0.262, p<0.0001), see figure. On multivariate binary logistic analysis, patients who demonstrated GLS recovery had greater reduction in scar size (OR=2.77 (1.09–7.01), p=0.032) and LV systolic reverse remodelling (OR=9.63 (1.21–76.41), p=0.032).

Follow-up parameters within GLS groups All patients (n=172) Group 1 (n=47) Group 2 (n=72) Group 3 (n=53) Follow-up GLS, % 16.02±3.44 19.38±1.90 16.36±2.09 12.57±2.69 GLS recovery, n 110 (64%) 19 (40%) 53 (74%) 38 (72%) Follow-up scar size, % 7.67±5.40 5.01±3.38 6.27±3.73 12.02±6.24 Follow-up LVEF, % 51.80±10.20 57.83±6.95 54.14±8.02 43.26±9.83 Data presented as mean ± SD or n (%).

Correlation graphs for change in GLS

Conclusion

Stratification of STEMI patients by baseline GLS was a determinant of CMR scar size as well as LV systolic function. However, the evaluation of GLS recovery could provide additional insights into reduction in scar size and LV systolic remodelling, both important prognostic markers. Thus, echocardiographic serial GLS evaluation may be a relevant non-invasive parameter, that is cheaper and more widely available for monitoring STEMI patients and guiding therapy.

P4343Reconciling acute coronary syndrome diagnoses between linked administrative data and hospital medical records in medical research

Background/Introduction

Administrative data incorporating the International Classification of Diseases 10th Revision (ICD-10) is commonly used in cardiac research. Using patient records, diagnoses are systematically coded by trained coders who have limited/no clinical experience. Therefore, it is important to understand how systematically coded cardiac diagnoses compare with clinically assessed diagnoses to better analyse and interpret studies that have used linked administrative data to adjudicate patient's diagnosis.

Purpose

To assess the agreement between the acute coronary syndrome (ACS) diagnoses according to linked data compared to those extracted from hospital medical records by clinicians participating in a national registry and determine the factors associated with diagnoses disagreement.

Methods

The rate of ST-elevation myocardial infarction (STEMI), non-STEMI (NSTEMI) and unstable angina (UA) obtained from the medical records, from admission to discharge, for the nationwide SNAPSHOT ACS audit in 2012 were compared to the corresponding ICD-10 Australian Modification (ICD-10-AM) codes using linked data from 6 jurisdictions covering all Australian states (6) and territories (2). The proportions of the overall agreement (OA), the positive agreement (PA) and the Cohen's weighted kappa and the 95% confidence interval (CI) were derived using both data sources for STEMI, NSTEMI and UA individually, where kappa≥0.8 confers strong agreement and 0.6≤kappa<0.8 moderate agreement. The factors associated with the diagnostic disagreement were explored using multilevel multivariable logistic regression model (backward selection method), accounting for the hospital clustering effect.

Results

Overall, 3130 patients had both medical records and linked data available for comparison. The degree of agreement was greatest for STEMI and lowest for UA (STEMI: OA=97%, PA=85%, kappa (95% CI)=0.84 (0.81, 0.87); NSTEMI: OA=91%, PA=81%, kappa (95% CI)=0.76 (0.73,0.79); UA: OA = 81%, PA=53%, kappa (95% CI)=0.41 (0.38, 0.45)). Further, the independent factors associated with the disagreement between the medical records and the linked data were the diagnosis of UA (UA vs. STEMI (odds ratio (95% CI)): 6.85 (4.12, 11.40)), not receiving revascularisation (2.27 (1.69, 3.03)), and the state where the ICD-10-AM was coded (p=0.007) (see Figure).

Figure 1

Conclusion

This study suggests that the agreement between the systematically coded diagnoses from linked administrative data and the diagnosis from the clinical assessment is greater in patients who received revascularisation and worse in those with UA. Also, the degree of agreement varies between states. As the linked data and the ICD codes are being used more often in research to support the evidence-based policies and practice, more attention is needed in testing and improving the accuracy of the ICD-10 codes as well as the ICD-11 codes that are soon to be introduced.

Acknowledgement/Funding

KH is funded by Heart Foundation Postdoctoral Fellowship. SNAPSHOT data linkage project was funded by the NSW Heart Foundation CVRN Project Grant

P2708Clopidogrel versus ticagrelor on coronary microvascular and peripheral endothelial function after non-ST elevation acute coronary syndrome: a randomised trial

Background

Ticagrelor has been shown to reduce microvascular injury and improve peripheral endothelial function compared to clopidogrel in ST-elevation myocardial infarction and stable patients. However, comparable data is lacking in non-ST elevation acute coronary syndromes (NSTE-ACS).

Purpose

To investigate the effects of clopidogrel versus ticagrelor on coronary microvascular function and peripheral endothelial function in NSTE-ACS patients.

Methods

Patients hospitalised for NSTE-ACS were prospectively randomised 1:1 to clopidogrel (300mg loading then 75mg daily) or ticagrelor (180mg loading then 90mg twice-daily). Coronary microvascular function was assessed with index of microcirculatory resistance (IMR) in the infarct related artery (IRA) and non-IRA before and after percutaneous coronary intervention (PCI) using a standard pressure-temperature coronary wire. Peripheral endothelial function was assessed with flow-mediated vasodilation (FMD) of the brachial artery, performed on admission prior to antiplatelet loading and again before discharge, using a pneumatic cuff and 10MHz linear ultrasound transducer.

Results

A total of 40 patients were included for analysis (Figure 1). Median age was 53.5 (IQR 49.0–61.5) years, 35 (87.5%) were male, 11 (27.5%) had diabetes, 19 (47.5%) were smokers. Median peak troponin T was 527 (175–1006.5) ng/L, median GRACE score 91.5 (78.3–103.3) and median SYNTAX score 13 (6–20). Baseline characteristics were similar between both groups. There was no significant difference in the median baseline IMR between the 2 groups in both the IRA (clopidogrel 14.4 [IQR 12.2–18.6] vs ticagrelor 20.8 [11.3–27.4], p=0.22) and non-IRA (14.0 [11.0–22.0] vs 14.0 [10.0–29.5] respectively, p=0.74). 28 patients underwent PCI to the IRA (12 clopidogrel, 16 ticagrelor). There was no significant difference in the median post-PCI IMR between the 2 groups (19.5 [14.5–24.5] vs 29.0 [19.0–35.6] respectively, p=0.11). However, there was significant worsening of post-PCI compared with pre-PCI IMR (19.5 vs 15.0, p=0.049) in the clopidogrel group but not in the ticagrelor group (29.0 vs 25.4, p=0.47). FMD was performed in 23 patients (9 clopidogrel, 14 ticagrelor). Admission median %FMD (change in post-stimulus diameter as a percentage of the baseline diameter) was similar between the 2 groups (13.2% [10.1–17.6] vs 12.2% [10.2–15.8] respectively, p=0.41). There was a trend towards higher median pre-discharge %FMD in the ticagrelor group (12.8% [12.2–18.0]) compared to the clopidogrel group (10.4% [9.5–11.2], p=0.09). There was a trend towards lower pre-discharge %FMD compared to admission in the clopidogrel group (10.4% vs 13.2%, p=0.05) but not the ticagrelor group (12.8% vs 12.2%, p=0.43).

Figure 1

Conclusions

In our NSTE-ACS patients undergoing PCI, ticagrelor resulted in less disruption of coronary microvascular function and may also have beneficial effects on peripheral endothelial function compared to clopidogrel.

Acknowledgement/Funding

Dr. James Xu is funded by a post-graduate scholarship from the Australian Government Research Training Program (RTP)

P1483Serial changes in peak left atrial strain predicts diastolic remodelling following percutaneous revascularisation for ST-segment elevation myocardial infarction

Background

Echocardiographic 2D speckle tracking peak left atrial (LA) strain reflects LA reservoir function. Limited studies have reported the relationship between peak LA strain and diastolic dysfunction. In addition, adverse diastolic remodeling (ADR) has been reported, to have better prognostic value than single diastolic function assessment following ST-elevation myocardial infarction (STEMI).

Purpose

We examined the relationship between serial changes in echocardiographic peak LA strain and diastolic function in STEMI patients.

Methods

186 percutaneously revascularized first presentation STEMI patients (87% male, 56.9±10.6 years) underwent serial TTE at baseline (2–7 days) and at follow-up (8–10 weeks) post-STEMI. Peak LA reservoir strain measurements were analysed from apical 2-, 3- and 4- chamber views. Diastolic function was graded as per 2016 guidelines: normal, grade 1, grade 2 and grade 3. ADR was defined as worsening of diastolic function grade (≥1) from baseline to follow-up, or persistent grade 3.

Results

Lower baseline peak LA strain was associated with grade 2 and grade 3 diastolic dysfunction compared to normal and grade 1 function at follow-up (p<0.05, see figure and table). Change in LA strain was less with worsening grades of diastolic function (see table). ADR was seen in 33 patients. Lower baseline peak LA strain predicted ADR (B=0.86 (0.80–0.92), p<0.0001). In addition, a reduction in peak LA strain at follow up was independently associated with ADR (B=0.91 (0.84–0.97), p=0.007) (see figure).

Diastolic function grades with LA strain Follow-up diastolic function Baseline peak LA strain (%) Follow-up peak LA strain (%) Change in peak LA strain (%) Normal (n=91) 35.70±6.38 40.97±8.10 5.26±6.07 Grade 1 (n=61) 30.70±6.97 34.54±8.77 3.84±6.32 Grade 2 (n=17) 23.95±6.11 25.49±5.93 1.54±4.70 Grade 3 (n=17) 23.66±8.07 23.49±10.64 −0.17±7.44 Data presented as mean ± SD.

Peak LA strain vs diastolic function

Conclusion

Peak LA strain is associated with diastolic function following STEMI and differentiates normal diastolic function from diastolic dysfunction. Serial changes in peak LA strain correlated with diastolic remodelling. Longer-term follow-up is required to determine the prognostic value of changes in peak LA strain, and diastolic remodelling.

Comparison of Clinical Outcomes Following Patients' First and Second Concussions

Purpose

The objective of this study was to examine differences in self-reported symptoms, neurocognitive performance, and vestibular-ocular insufficiencies between patients’ first and second concussions. A secondary purpose was to explore the role of risk factors on recovery.

Methods

We conducted a retrospective medical chart review of 73 (32-M/41-F) patients aged 15.69 (SD=1.67) years from a concussion specialty clinic with two separate concussions (84.9% of 1st and 79.5% of 2nd sport-related) that occurred between August 2010 and April 2018. Clinical outcomes included the PCSS, ImPACT, and the Vestibular/Ocular Motor Screening (VOMS). A series of paired samples t-tests were used to compare clinical outcomes along with chi-square analyses for risk factor associations.

Results

Verbal memory scores were higher following the second (M=80.67, SD=15.3) (M=76.32, SD=15.65) (t[73]=–2.18, p=.03) concussion. Visual motor processing speed was faster following the second concussion (M=35.04, SD= 7.90) (M=31.35, SD=7.63) (t[73]=–5.72, p<.001). There were no other significant differences observed. Recovery time was similar for the first (61.07, SD=58.41.5) and second (67.91 SD=70.10) respectively, t(70)=–.91, p=.37. There was no relationship between any risk factors, and recovery time for either injury with the exception a significant association between gender and recovery time (>21 days) with the 1st injury for females (χ2, N=73)=10.58, p=.001.

Conclusion

Findings suggest that a second concussion does not result in more pronounced symptoms, worse neurocognitive performance, or increased deficits on vestibular/ocular performance and/or longer recovery time. The only significant risk factor to a recovery over 21 days included gender.

Pharmacokinetics of trastuzumab emtansine (T-DM1) as a single agent or in combination with pertuzumab in HER2-positive breast cancer patients with recurrent or locally advanced metastatic breast cancer

PURPOSE

The phase III MARIANNE study investigated single-agent trastuzumab emtansine (T-DM1) and combination T-DM1 plus pertuzumab as the first-line treatment for human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer (MBC). Pharmacokinetic properties of T-DM1 and pertuzumab in these patients and the potential for drug-drug interactions (DDIs) were assessed.

METHODS

Pharmacokinetic samples of T-DM1-related analytes (T-DM1 conjugate, total trastuzumab, DM1) and pertuzumab were analyzed. Observed pharmacokinetic data were summarized for all analytes. Historical population pharmacokinetic models for T-DM1 conjugate and pertuzumab in HER2-positive MBC were used to derive empirical Bayes estimates of pharmacokinetic parameters.

RESULTS

In MARIANNE (N = 375), mean ± standard deviation population pharmacokinetic model-predicted Cycle 1 C_max for T-DM1 conjugate was 74.4 ± 10.1 µg/mL, Cycle 1 C_trough was 1.34 ± 0.802 µg/mL, and area under the concentration-time curve from time zero to infinity after first dose (AUC_inf) was 338 ± 69.5 µg*day/mL. These values were similar to other T-DM1 studies. Pharmacokinetics of T-DM1 conjugate and other analytes (total trastuzumab, DM1) were similar with or without pertuzumab. In the pertuzumab plus T-DM1 arm, mean model-predicted Cycle 1 pertuzumab C_max, C_trough, and AUC_inf were 276 ± 50.0 µg/mL, 64.8 ± 17.9 μg/mL, and 4470 ± 1360 µg*day/mL, respectively. These values were similar to other pertuzumab studies.

CONCLUSIONS

Based on the population pharmacokinetic analysis of T-DM1 conjugate and pertuzumab, pharmacokinetics are similar across different lines of treatment and stages of disease including previously untreated MBC patients, and no DDIs were identified for combined use of T-DM1 and pertuzumab.

Abstract P2-14-26: Withdrawn

This abstract was withdrawn by the authors.

Citation Format: Meybodi F, Sedaghat N, French J, Elder E. Withdrawn [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P2-14-26.