Co-delivery of HIV pre-exposure prophylaxis (PrEP) and HIV testing among publicly insured adolescents and young adults (AYA) receiving medication for opioid use disorder (MOUD)

BACKGROUND

Low rates of HIV pre-exposure prophylaxis (PrEP) prescribing contribute to the disproportionate burden of HIV in the United States. Among adolescent and young adults (AYA) with opioid use disorder, HIV testing and PrEP co-prescription rates are poorly characterized.

METHODS

We performed a retrospective analysis involving deidentified data from Philadelphia's Medicaid beneficiaries ages 16-29 years who were prescribed medication for opioid use disorder (MOUD) from 2015 to 2020 and continuously Medicaid-enrolled for ≥6 months prior to that prescription. After identifying the presence of a qualifying diagnosis signifying a PrEP indication, we examined the outcome of appropriate PrEP co-prescriptions and HIV testing using generalized estimating equations (GEE) modeling.

RESULTS

We identified 795 AYA Medicaid beneficiaries with 1269 qualified treatment episodes. We calculated a PrEP prescribing rate of 29.47 per 1000 person-years among AYA receiving MOUD. The HIV testing rate was 63.47 per 1000 person-years among AYA receiving MOUD. GEE modeling revealed that individuals receiving methadone were more likely (aOR=2.62, 95% CI=1.06-6.49) to receive HIV testing within 6 months after a PrEP-qualifying diagnosis compared to those receiving other MOUD medications. Those who only saw outpatient behavioral health providers were less likely (aOR=0.48, 95% CI=0.24-0.99) to have received an HIV test within 6 months after the PrEP-qualifying diagnosis compared to those receiving inpatient behavioral health services.

CONCLUSIONS

Co-prescription of PrEP and HIV testing among AYA receiving MOUD was rare in this large urban publicly insured population. Interventions are needed to increase HIV prevention services for this key population of AYA at risk for HIV infection.

Variational quantum eigensolver for closed-shell molecules with non-bosonic corrections

The realization of quantum advantage with noisy-intermediate-scale quantum (NISQ) machines has become one of the major challenges in computational sciences. Maintaining coherence of a physical system with more than ten qubits is a critical challenge that motivates research on compact system representations to reduce algorithm complexity. Toward this end, the variational quantum eigensolver (VQE) used to perform quantum simulations is considered to be one of the most promising algorithms for quantum chemistry in the NISQ era. We investigate reduced mapping of one spatial orbital to a single qubit to analyze the ground state energy in a way that the Pauli operators of qubits are mapped to the creation/annihilation of singlet pairs of electrons. To include the effect of non-bosonic (or non-paired) excitations, we introduce a simple correction scheme in the electron correlation model approximated by the geometrical mean of the bosonic (or paired) terms. Employing it in a VQE algorithm, we assess ground state energies of H2O, N2, and Li2O in good agreement with full configuration interaction (FCI) models respectively, using only 6, 8, and 12 qubits with quantum gate depths proportional to the squares of the qubit counts. With the adopted seniority-zero approximation that uses only one half of the qubit counts of a conventional VQE algorithm, we find that our non-bosonic correction method reaches reliable quantum chemistry simulations at least for the tested systems.

Fixed-Bearing Unicompartmental Knee Arthroplasty in Tibia Vara Knees Results in Joint Surface Malalignment and Varus Joint Line Obliquity, but Does Not Affect Functional Outcomes at Greater Than 5 Years Follow-Up

BACKGROUND

This study aimed to investigate the clinical outcomes of fixed-bearing medial unicompartmental knee arthroplasty (UKA) for tibia vara knees and the associated changes in joint space malalignment (JSM) and joint line obliquity (JLO).

METHODS

We retrospectively analyzed a consecutive group of 100 patients who underwent fixed-bearing medial UKA with a preoperative medial proximal tibia angle (MPTA) ≥86° (n = 50) and MPTA <86° (n = 50) and who had a minimum 5-year follow-up. Radiological parameters, including the hip-knee-ankle angle, MPTA, and the postoperative JSM and JLO, were measured. Functional evaluation was performed using the range of motion, visual analog scale, Knee Society Knee Score, Knee Society Function Score, and Western Ontario and McMaster Universities Osteoarthritis Index score.

RESULTS

The MPTA <86° group showed significantly higher postoperative JLO (91.8 versus 90.4°, respectively; P = .002) and JSM (6.1 versus 4.2°, respectively; P = .026) compared to the MPTA ≥86° group. Functional outcomes, including range of motion, visual analog scale, Knee Society Knee Score, Knee Society Function Score, and Western Ontario and McMaster Universities Osteoarthritis Index scores, were not significantly different between the 2 groups.

CONCLUSIONS

Fixed-bearing medial UKA is a safe and effective surgical option for patients who have tibia vara knees, as an increase in JLO and JSM postoperatively does not have a clinically relevant impact, even after a minimum 5-year follow-up.

Controlled posterior condylar milling technique for unicompartmental knee arthroplasty minimises tibia resection during gap balancing: Short-term clinical results

PURPOSE

The purpose of this study was to demonstrate the clinical utility of controlled posterior condylar milling (CPCM) in gap balancing while minimally resecting the tibia during fixed-bearing unicompartmental knee arthroplasty (UKA).

METHODS

This study is a retrospective cohort study. Patients who underwent medial UKA for isolated medial compartment osteoarthritis with a minimum follow-up of 2 years were included. The patients were divided into two groups: the conventional group (n = 56) and the CPCM group (n = 66). In the CPCM group, the proximal tibia was resected at the level of the distal end of the subchondral bone. If the flexion gap was tighter than extension, the posterior condyle was additionally milled to adjust gap tightness. Standing knee X-ray and scanogram were used to evaluate alignment and tibia resection amount. Range of motion (ROM) and Western Ontario McMaster Universities Osteoarthritis Index (WOMAC) scores were used to evaluate clinical outcomes.

RESULTS

The CPCM group showed significantly smaller tibia resection (3.6 ± 1.9 mm) compared to the conventional group (5.2 ± 2.7 mm) (p < 0.001). Postoperative ROM (133.0 ± 8.3°, 135.2 ± 7.2°, n.s.) and WOMAC (19.3 ± 13.6, 23.6 ± 17.7, n.s.) were not significantly different between the two groups. Postoperative periprosthetic fractures occurred in two patients in conventional group, while the CPCM group had no periprosthetic fractures.

CONCLUSION

The CPCM technique may be a simple and useful intraoperative technique that can achieve minimal tibia resection and promising clinical outcomes while easily adjusting gap tightness between flexion and extension during medial fixed-bearing UKA.

LEVEL OF EVIDENCE

Level III.

Suprapatellar intramedullary nail combined with screw fixation has comparable surgical outcomes to minimally invasive locking plate fixation in ipsilateral tibial plateau and shaft fractures

PURPOSE

To compare union rate, union time, alignment, and complication rate in ipsilateral tibia plateau and shaft fractures treated via suprapatellar intramedullary nailing with screw fixation and minimally invasive locking plate fixation.

MATERIALS AND METHODS

A retrospective study was conducted on 48 patients who underwent minimally invasive plate fixation (n = 35) or suprapatellar intramedullary nailing with screw fixation (n = 13), for the treatment of ipsilateral tibial plateau and shaft fractures with at least 1-year follow-up. Union rate, union time, radiologic alignment, and complication rate such as malalignment, nonunion, and fracture-related infection (FRI) were investigated.

RESULTS

Demographic data were not different between the two groups. Coronal plane alignment was 0.17 ± 4.23 in the plate group and -0.48 ± 4.17 in the intramedullary nail group (p = 0.637). Sagittal plane alignment was -0.13 ± 5.20 in the plate group and -1.50 ± 4.01 in the suprapatellar intramedullary nail group (p = 0.313). Coronal and sagittal malalignment recorded equal results: (p > 0.99), FRI (p = 0.602), nonunion and union times recorded (p = 0.656) and (p = 0.683, 0.829), respectively, and showed no significant difference between the two groups.

CONCLUSION

Suprapatellar intramedullary nailing with screw fixation had similar surgical outcomes with minimally invasive locking plate fixation in ipsilateral tibial plateau and shaft fractures in terms of union rate, union time, alignment, and complication rate. Thus, frequent use of intramedullary nailing combined with screw fixation is anticipated in patients with ipsilateral tibial plateau and shaft fractures when the soft tissue condition is not desirable.

LEVEL OF EVIDENCE

Level III.

Comparison of suprapatellar intramedullary nailing versus minimal invasive locked plating for proximal tibia fractures

PURPOSE

To compare the radiological alignment, union time, union rate, and complication rate between suprapatellar intramedullary nails and minimally invasive locking plate fixation in the treatment of proximal tibial fractures.

MATERIALS AND METHODS

We retrospectively analyzed 103 patients who underwent plate fixation (n = 50) or suprapatellar intramedullary nailing (n = 53) for proximal tibial fractures involving the meta-diaphyseal junction between November 2015 and October 2020 at our institution. The union rate, union time, radiologic alignments, and complications, such as malalignment, nonunion, and deep infection, were investigated.

RESULTS

The demographic data did not differ between the plate and suprapatellar intramedullary nail groups. The alignment of the coronal plane was 0.24 ± 3.19 in the plate group and - 0.49 ± 2.22 in the intramedullary nail group (p = 0.196). Sagittal plane alignment was - 0.29 ± 4.97 in the plate group and 0.24 ± 4.12 in the intramedullary nail group (p = 0.571), and coronal malalignment (p = 0.196), sagittal malalignment (p = 0.57), deep infection (p = 0.264), nonunion (p = 0.695), union time (p = 0.329), and final union rate (p = 0.699) were not significantly different between groups.

CONCLUSION

Compared with the minimally invasive locking compression plate group, the suprapatellar intramedullary nail group yielded comparable results in terms of radiological alignment and complications. Considering that proximal tibial fractures are associated with high-energy trauma and severe soft tissue damage, we believe that a suprapatellar intramedullary nail may be a good alternative.

LEVEL OF EVIDENCE

Level III.

Can bone scintigraphy reflect the progression of osteoarthritis after unicompartmental knee arthroplasty?

BACKGROUND

Bone scintigraphy (BS) has been reported to be a useful predictor of osteoarthritis (OA) progression in primary knee OA. However, no previous studies have explored the relationship between BS and OA progression in the retained compartments after unicompartmental knee arthroplasty (UKA). Thus, we evaluated whether OA progresses to other compartments in patients who undergo UKA and if increased uptake on BS is associated with OA progression in other compartments after UKA.

METHODS

A total of 41 patients with knee BS at least five years after UKA were included. Radiographic OA progression in other compartments was assessed by grading and comparing OA severity in each patient using the Kellgren-Lawrence grading system (K-L grade) and Osteoarthritis Research Society International (OARSI) atlas score. After UKA, the correlation between BS uptake and radiographic OA progression was analyzed in each retained compartment. A correlation analysis was also performed to evaluate the association between BS uptake and OA progression grades.

RESULTS

A significant progression of OA was observed in both contralateral tibiofemoral and patellofemoral compartments after UKA at 98.5 ± 26.0 months of follow-up (all p<0.001). No correlation was found between BS uptake and radiographic OA progression nor between BS uptake and radiographic OA progression grade in the contralateral and patellofemoral compartments.

CONCLUSIONS

Following UKA, OA progresses in the retained contralateral tibiofemoral and patellofemoral compartments over a minimum five-year follow-up period. Thus, BS is ineffective in assessing the progression of OA in these compartments.

Lateral Retinacular Release During Medial Unicompartmental Knee Arthroplasty in the Presence of Patello-Femoral Joint Arthritis Relieves Patello-Femoral Joint Pressure and Improves Associated Symptoms

BACKGROUND

This study evaluated the effects of concomitant lateral patellar retinacular release (LPRR) during medial unicompartmental knee arthroplasty (UKA).

METHODS

We retrospectively analyzed 100 patients who had patello-femoral joint (PFJ) arthritis who underwent medial UKA with (n = 50) and without (n = 50) LPRR who had ≥2 years follow-up. Radiological parameters associated with lateral retinacular tightness, including patellar tilt angle (PTA), lateral patello-femoral angle (LPFA), and congruence angle, were measured. Functional evaluation was performed using the Knee Society Pain Score, Knee Society Function Score (KSFS), Kujala Score, and the Western Ontario McMaster Universities Osteoarthritis Index score. Intraoperative patello-femoral pressure evaluation was performed on 10 knees to evaluate the pressure changes before and after LPRR. Mann-Whitney U-tests were used for statistical analyses.

RESULTS

Demographic data did not differ between the LPRR(+) and LPRR(-) groups. A decrease in PTA and an increase in LPFA were observed in the LPRR(+) group compared to those in the LPRR(-) group (PTA; -0.54 versus -1.74, P = .002, LPFA; 0.51 versus 2.01, P = .010). The LPRR(+) group showed significantly better KSFS and Kujala scores than the LPRR(-) group (KSFS: 90 versus 80, P = .017; Kujala score: 86 versus 79, P = .009). Intraoperative patello-femoral pressure analysis showed a 22.6% reduction in the PFJ contact pressure and an 18.7% reduction in PFJ peak pressure after LPRR. (P = .0015, P < .0001, respectively) CONCLUSION: A LPRR during UKA may be a simple and useful adjunct procedure to relieve PFJ symptoms with concomitant PFJOA.

Electron Temperature Measurements Using a Two-Filter Soft X-ray Array in VEST

A multichannel soft X-ray (SXR) array has been developed to measure the electron temperature in the Versatile Experiment Spherical Torus (VEST). To estimate electron temperature using the two-filter method applied to SXR intensity, we designed a pinhole camera that has two photodiode arrays with different metallic filters. We also adopted a filter wheel and tested various filter parameters to find the optimal filter set. Through tests, the combination of aluminum and beryllium was found to be the most suitable for the current experimental conditions in VEST. The filtered SXR signals were acquired with a low-noise preamplifier, exhibiting sufficient signal-to-noise ratios for electron temperature estimation based on the intensity ratio of two signals obtained with different filters. The estimated electron temperature from the developed two-filter SXR array showed reasonably matched levels and consistent trends with Thomson scattering measurements. Error contribution from impurity line emission is also discussed.

Impact of Workflow and Educational Interventions on MR Safety in Radiation Oncology

PURPOSE/OBJECTIVE(S)

Magnetic resonance imaging (MRI) is becoming increasingly integrated into radiation oncology (RO) departments with the use of MRI-Linacs and MRI simulation. Due to the number of implants in patients with cancer, adoption of comprehensive patient screening and MR safety workflows in RO is critical. Identifying MR unsafe implants only at the time of MRI simulation leads to same-day cancellations, potentially delaying treatment, and can risk MR safety events (SEs). This quality improvement study evaluated the impact of workflow and educational interventions on MR safety in RO at a single institution.

MATERIALS/METHODS

In an effort to decrease same-day cancellations and improve safety surrounding use of a 3 Tesla MRI simulator at an academic center, three plan-see-do-act (PDSA) cycles were implemented from 4/18/22 - 1/19/23. MR safety oversight for the simulator was provided by a multidisciplinary team, with input from both radiology and RO. PDSA cycle 1 implemented a two-screen functional workflow, adapted from radiology at the same institution. The first screen is completed by the practice coordinator (PC) at the time of scheduling to triage high-risk patients into a work queue (WQ) for further evaluation by the MR safety team. The second screen is performed by the MR technologist (MRT) at the point of care. PDSA cycle 2 involved education for PCs. PDSA cycle 3 was a second PC educational intervention including a visual aide to assist with WQ use. Efficacy was determined by the number of same-day cancellations, patients in the WQ (a measure of the number of patients identified at the initial screen as having an implant), and SEs in each PDSA cycle.

RESULTS

PDSA cycle 1 spanned 56 workdays during which 91 MR simulations were scheduled with 6 cancellations (6.5%). PDSA cycle 2 spanned 84 days during which 173 MR simulations were scheduled with 18 cancellations (10.4%). PDSA cycle 3 spanned 39 workdays and had 94 MR simulations, with 7 cancellations (7.4%). The cancellation rate during each PDSA cycle was 0.11, 0.21, and 0.17 cancellations/day, respectively. The number of patients in the WQ during each PDSA cycle, representing successfully screened high-risk patients, was 0, 0, and 3, respectively. There were no SEs during the study.

CONCLUSION

In this study, an MR safety workflow from radiology was successfully implemented in RO. There were no SEs during the study, but the number of patients successfully screened as high-risk and placed in the WQ increased after repeat PC education. Further increases in WQ use would decrease the demand for implant assessment at point of care, which could decrease burden on the MRT, same day cancellations, and potentially SEs. This will be especially important if case load increases. Future work could expand educational efforts to additional staff.

Rotational stability can be enhanced in revision anterior cruciate ligament reconstruction using the over-the-top augmentation technique compared to single bundle technique

PURPOSE

Revision anterior cruciate ligament (ACL) reconstruction is technically challenging due to mispositioned tunnels, bone loss, and tunnel enlargement, which may compromise graft fixation and result in failure. To obtain firm graft fixation and strength in one stage, we utilized an over-the-top augmentation technique using an Achilles tendon allograft in revision ACL reconstruction (OA-ACLR). This study compared OA-ACLR with single-bundle ACL reconstruction (SB-ACLR). We hypothesized that OA-ACLR would enhance the postoperative knee joint rotational stability.

METHODS

We retrospectively analyzed 47 patients who underwent revisional OA-ACLR and 48 who underwent primary SB-ACLR with minimum follow-up of 6 months. Knee instability was evaluated with the anterior drawer, Lachman, and pivot shift tests preoperatively and at the final follow-up. Side-to-side differences were compared with the non-affected side at the final follow-up. Function was evaluated using the IKDC subjective and Lysholm knee scores preoperatively and at the final follow-up.

RESULTS

The groups did not differ in terms of sex, age, BMI, and etiology. There were no significant differences in concomitant surgical procedures, such as meniscectomy and meniscus repair, between the two groups (p = 0.335, > 0.99). Both groups significantly improved in the anterior drawer, Lachman, pivot shift tests, and IKDC and Lysholm knee scores after surgery (all p < 0.001). The OA-ACLR group showed significantly higher rotational stability in the pivot shift test than the SB-ACLR group (p = 0.017). The postoperative side-to-side difference, the IKDC and Lysholm scores showed no significant differences between the groups (p = 0.34, 0.301, 0.438).

CONCLUSIONS

OA-ACLR showed enhanced rotational stability with pivot shift test compared to SB-ACLR. It may be considered a useful alternative for revision ACL reconstruction.

Fibrocartilage extracellular matrix augmented demineralized bone matrix graft repairs tendon-to-bone interface in a rabbit tendon reconstruction model

Current tendon/ligament reconstructions integrate via scar tissue rather than proper bone-tendon interface regeneration, which affects graft longevity, changes in bone tunnel size, and functional outcomes. The purpose of this study was to develop a functional demineralized bone matrix (DBM) + fibrocartilage extracellular matrix (FCECM) composite scaffold, characterize its physicochemical properties, and evaluate its efficacy in repairing tendon-bone interface in a rabbit tendon reconstruction model. Solubilized FCECM was loaded and crosslinked on to DBM scaffolds via gamma-irradiation to create DBM + FCECM scaffolds. The resulting scaffold showed interconnected pores coated with FCECM and protein cargo similar to FCECM. The addition of FCECM modified the physicochemical properties of the DBM scaffold, including microstructure, biochemical composition, mechanical strength, thermodynamic properties, and degradation period. The DBM + FCECM scaffold was biocompatible for mesenchymal stem cells (MSCs) and resulted in elevation of fibrochondrogenic gene markers compared to DBM scaffolds in vitro. In vivo implantation of DBM + FCECM scaffold resulted in neofibrocartilage formation, better pullout strength, and less bone tunnel widening compared to DBM only group in a rabbit tendon reconstruction model. In conclusion, the FCECM augmented DBM scaffold repairs the tendon-bone interface with osseous-fibrocartilage tissue, which may be utilized to improve current tendon reconstruction surgeries.

Abstract 4006: TRX-221, a novel 4th-generation EGFR inhibitor for overcoming C797S mutation-mediated acquired resistance in NSCLC

Targeting mutated EGFR is a clinically validated approach for tackling non-small cell lung cancer (NSCLC). Approximately 20% of patients with advanced NSCLC harbor an EGFR mutation. Osimertinib is a 3rd-generation oral EGFR-TKI targeting the EGFR sensitizing mutations Del19 and L858R, as well as an acquired mutation, T790M. Despite osimertinib's efficacy in NSCLC, resistance develops and the mechanisms of resistance to osimertinib are complex. Development of another mutation, C797S is the most common mechanism of acquired resistance following osimertinib treatment. This mutation occurs with about 12% frequency after a 1L therapy of osimertinib, and with approximately 17% frequency after a 2L therapy. Here, we report TRX-221 as a novel 4th-generation EGFR-TKI that can overcome C797S-mediated acquired resistance in NSCLC models in vitro and in vivo. TRX-221 exhibited potent inhibitory activity against multiple EGFR mutant kinases, including Del19/T790M/C797S, L858R/T790M/C797S, Del19/C797S, L858R/C797S, Del19/T790M, L858R/T790M, Del19, and L858R. Likewise, TRX-221 potently inhibited the proliferation of Ba/F3 cells stably overexpressing these eight EGFR mutants. TRX-221 however showed sparing activity against EGFR wild-type kinase and cell lines. TRX-221 also demonstrated marked anti-proliferative activity against osimertinib-resistant patient-derived cancer cell lines (PDCs). With favorable DMPK profiles, once-daily oral dosing of TRX-221 induced strong anti-tumor effects in a dose-dependent manner in a variety of osimertinib-resistant CDX and PDX models. As a reversible, selective, and broad-spectrum 4th-generation EGFR-TKI, TRX-221 is currently undergoing IND-enabling studies and shows strong potential as a therapeutic solution to treat advanced NSCLC patients harboring EGFR mutations.

Citation Format: Sumin Lim, Seulgi Choi, Ju-Kyung Lee, Eunhyun Choi, Sungwon Lee, Kwangwoo Chun, Myoungki Baek, Jiyeon Park, Jihyun Kim, Areum Kang, Younghoon Kim, Namkyoung Kim, Byoungchul Cho, Taebo Sim, Koo Lee. TRX-221, a novel 4th-generation EGFR inhibitor for overcoming C797S mutation-mediated acquired resistance in NSCLC. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 4006.

A36 INVESTIGATING TYPE 1 REGULATORY T CELLS AS A THERAPY FOR INFLAMMATORY BOWEL DISEASE USING A MOUSE MODEL OF ACUTE INTESTINAL EPITHELIAL DAMAGE

Background

Inflammatory bowel disease (IBD) affects an estimated 270,000 people in Canada and is rapidly increasing in prevalence. All patients have relapsing disease, and a subset of individuals do not respond to current treatments. Further, there are no approved treatment options in Canada that reverse IBD-induced intestinal fibrosis. We have previously shown type 1 regulatory cells (Tr1s) are capable of suppressing inflammatory macrophages, promote barrier function of human intestinal epithelial cells, and induce differentiation of mucin-producing goblet cells. We hypothesize that Tr1 cells can prevent inflammatory damage and fibrosis in an mouse model of acute gut damage.

Purpose

We hypothesize that Tr1 cells can prevent inflammatory damage and fibrosis in an mouse model of gut damage. Here we evalute the therapeutic potential of Tr1 cells in an model of acute intestinal epithelial damage.

Method

Tr1 cells were isolated and expanded from CD4⁺ CD44^high FOXP3^- cells. Their phenotype was characterized by flow cytometry and cytokine secretion was measured via ELISA. WT B6 mice were given 2% DSS in H₂O for 7 days, followed by H₂O alone for 7 days. Prior to DSS treatment, mice were sub-lethally irradiated to facilitate engraftment, and given I.P. injections of PBS or 0.5 – 2 x 10⁶ Tr1 cells. Mice weights and health scores were recorded daily. At the endpoint, blood, spleen, and mesenteric lymph nodes were analyzed for Tr1 cell engraftment (or lack thereof) for each mouse. Complete white blood counts were performed for each mouse. Additionally, proximal, medial, and distal portions of the ileum were processed for histologic scoring.

Result(s)

Tr1 cells isolated from CD4⁺ CD44^high FOXP3^- cells produce high levels of IL-10 following stimulation (>35,000 pg/ml/1 x 10⁵ cells). Additionally, these cells express high levels of Tr1 markers CD49b and Lag-3. Optimization experiments indicated no significant differences between mice irradiated and given DSS and mice only given DSS (no irradiation). Our results suggest no significant differences in inflammatory cell infiltrate scores between control and Tr1 treated mice. However, gut architecture scores appeared to improve with increasing Tr1 doses. Further, weight change improved with Tr1 treatment, as compared to PBS controls. Interestingly, Tr1 treatment appeared to decrease total eosinophil and neutrophil counts from peripheral blood.

Conclusion(s)

Our initial findings indicate Tr1 adoptive transfer prior to acute damage via DSS improves gut damage and weight loss.

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CIHR

Disclosure of Interest

None Declared

1323 VOLUNTEER-LED ONLINE GROUP EXERCISE FOR OLDER ADULTS: A FEASIBILITY AND ACCEPTABILITY STUDY

Introduction

The health benefits of physical activity for older people are well recognised and include reduction in falls, improvement in frailty status and physical function. Nonetheless, physical inactivity remains a significant problem among older adults. This study aimed to determine the feasibility and acceptability of implementing online volunteer-led group exercise for community-dwelling older adults.

Methods

This pre-post mixed methods study was conducted among older adults attending community social clubs. Eligible participants were aged ≥ 65 years, able to walk independently, and able to provide written consent. The intervention consisted of a once weekly volunteer-led online group chair-based exercise. The primary outcomes were the feasibility and acceptability of the intervention. Secondary outcomes included physical activity levels measured using the Community Health Model Activities Program for Seniors (CHAMPS) questionnaire, functional status (Barthel Index), and health-related quality of life (EQ-5D-5L). Outcomes were measured at baseline and at 6 months. Trials registration: NCT04672200.

Results

Nineteen volunteers were recruited, 15 completed training and 9 were retained (mean age 68 years, 7 female). Thirty participants (mean age 77 years, 27 female) received the intervention and attended 54% (IQR 37-67) of exercise sessions. One minor adverse event was reported. Participants had no significant changes in secondary outcome measures, with a trend towards improvement in physical activity levels. The intervention was acceptable to volunteers, participants, and staff. The seated exercises were perceived as safe, manageable and enjoyable. Volunteers were relatable role models providing positive vicarious experiences that improved participants confidence to exercise within a friendly, non-judgmental environment. Technological issues, or reluctance to learn how to use technology were barriers to the intervention. The social interactions and sense of belonging motivated participation.

Conclusions

Trained volunteers can safely deliver online group exercise for community-dwelling older adults and the intervention was feasible and acceptable to older adults, volunteers and club staff.

Levels of physical activity and sitting time in women with infants, toddlers and preschoolers: a population-based cross-sectional study

OBJECTIVES

Insufficient physical activity (PA) and prolonged sitting time (ST) increase the risk of chronic disease and mortality. Caring for young children can potentially impact maternal PA and sedentary behaviours. The aims of this study were to explore the levels of PA and ST in women with young children (infants, toddlers and preschoolers) and sociodemographic and behavioural factors associated with these.

STUDY DESIGN

This was a population-based cross-sectional study.

METHODS

Survey 5 data collected in 2009 (n = 4290) of the 1973-1978 birth cohort of the Australian Longitudinal Study on Women's Health were used. Multiple linear and logistic regression models were used to examine associations.

RESULTS

In adjusted models, compared with women with preschoolers, women whose youngest child was an infant aged 0-6 months, aged >6-12 months or toddler had lower PA (-321.3 MET.min/week [95% confidence interval (CI) -416.2, -226.4], -147.9 MET.min/week [95% CI -237.6, -58.1] and -106.4 MET.min/week [95% CI -172.3, -40.5]). ST was higher in women whose youngest child was an infant aged 0-6 months (0.48 h/day; 95% CI 0.19, 0.77) but lower with infants aged >6-12 months (-0.33 h/day; 95% CI -0.60, -0.05) and toddlers (-0.40 h/day; 95% CI -0.60, -0.20) than in those with preschoolers. The findings were similar in the logistic model. Sociodemographic and behavioural factors such as occupation and marital status also influenced PA and ST.

CONCLUSIONS

Women with infants and toddlers have lower PA than women with preschoolers. Women are more likely to sit more in the first 6 months after childbirth. These findings can inform resources and intervention development to improve activity levels in women with young children through consideration of the age of the youngest child, sociodemographic and behavioural factors.

The long-term cardiac events after coronary bifurcation stenting with second-generation drug-eluting stents in elderly patients are comparable to those of younger patients

Background

Elderly patients undergoing percutaneous coronary intervention (PCI) generally have a high risk of adverse clinical outcomes. We investigated the long-term clinical impact of PCI on coronary bifurcation disease in elderly patients in Korea and Italy.

Methods

From the BIFURCAT (comBined Insights from the Unified RAIN and COBIS bifurcAtion regisTries) data, we evaluated 5,537 patients who underwent PCI for coronary bifurcation disease. The primary outcome was major adverse cardiac events (MACEs), defined as the composite of target vessel myocardial infarction, target lesion revascularisation, and stent thrombosis. Kaplan–Meier estimates and Cox proportional hazard models were used to compare elderly patients (aged ≥75 years) and younger patients (aged &lt;75 years).

Results

A total of 1,415 patients (26%) were aged ≥75 years. Elderly patients were more frequently female, had higher rates of hypertension and chronic kidney disease (CKD), and presented more frequently with left main (LM) disease. After a median follow-up of 2.1 years, MACEs were comparable between elderly and younger patients. In multivariable analysis, old age was not an independent predictor of MACEs (p=0.977). In elderly patients, CKD and LM disease were independent predictors of MACEs, whereas in younger patients, hypertension, diabetes, CKD, reduced left ventricular ejection fraction, LM disease, and two-stent strategy usage were independent predictors.

Conclusions

Elderly patients who underwent coronary bifurcation PCI with second-generation drug-eluting stents demonstrated similar clinical outcomes to those of younger patients. Both CKD and LM disease were independent predictors of MACEs, regardless of age after coronary bifurcation PCI.

Funding Acknowledgement

Type of funding sources: None.

The differential effects of antihypertensive drugs on central blood pressure: nebivolol versus telmisartan (ATD-CBP)

Background

Central blood pressure and central pulse pressure have a better correlation with the risk of cardiovascular disease compared to those of peripheral measurement. In a previous study, a second-generation beta-blocker showed poor CBP-lowering effects. However, the effect on CBP by third-generation beta-blockers is not fully elucidated. Thus, this randomised study investigated whether nebivolol-based hypertension treatment may confer advantages over telmisartan, an angiotensin II receptor-blocker, in reducing CBP.

Methods

This was a prospective, randomised, multicentre, open-label, controlled trial that evaluated 98 hypertensive patients. Patients received either nebivolol- (N=49) or telmisartan-based (N=49) treatment for hypertension for 12 weeks with a target BP of ≤140/80. The primary outcome was the difference in change from baseline central systolic BP (cSBP) after 12 weeks.

Results

There were no significant differences between the two groups in baseline central and peripheral SBP. The mean change in cSBP from baseline (ΔcSBP) was −17.2±3 mmHg for nebivolol group (P&lt;0.001) and −29.9±3 mmHg for telmisartan group (P&lt;0.001). The difference in ΔcSBP between the two groups was significant (12.7mmHg, 95% confidence interval [CI], 4.13 to 21.2; P=0.004). Peripheral SBP (pSBP) decreased less in nebivolol group compared to telmisartan group (−18.0±3 in nebivolol group vs. −26.3±3 in telmisartan group, P=0.032). After adjusting for reduction in pSBP, reduction in cSBP was higher in telmisartan group compared to nebivolol group, as shown by the ratio of changes in cSBP and pSBP (ΔcSBP/ΔpSBP; 0.67 for nebivolol group vs. 1.11 for telmisartan group, P=0.080), albeit without statistical significance.

Conclusions

Nebivolol-based hypertension treatment may have less potent CBP-lowering effects compared to telmisartan. However, larger-scale studies are warranted to further elaborate our findings.

Funding Acknowledgement

Type of funding sources: None.

Effect of an early invasive strategy based on time of symptom onset in patients with non-ST elevation myocardial infarction

Background

A limitation of the current guidelines of the timing of invasive coronary angiography (ICA) for patients with non-ST-segment elevation (NSTE) acute coronary syndrome is based on randomization time. So far, no study has reported the clinical outcomes of invasive strategy timing based on the time of symptom onset. Herein, we aimed to investigate the effect of invasive strategy timing from the time of symptom onset on the 3-year clinical outcomes of patients with NSTE myocardial infarction (MI).

Methods and results

Among 13,104 patients from the Korea Acute Myocardial Infarction Registry-National Institutes of Health, we evaluated 5,856 patients with NSTEMI. The patients were categorized according to symptom-to-catheter (StC) time (&lt;48 h and ≥48 h). The primary outcome was 3-year all-cause mortality, and the secondary outcome was a 3-year composite of all-cause mortality, recurrent MI, and hospitalization for heart failure. Overall, 3,919 (66.9%) patients were classified into the StC time &lt;48 h group. This group had lower all-cause mortality than the StC time ≥48 h group (7.3% vs. 13.4%, p&lt;0.001). The continuous association of StC time and risk of primary and secondary endpoints showed shorter StC time (reference: 48 h), and lower adjusted hazard ratio reduction was observed. In multivariable analysis, independent predictors of delayed ICA were older age, non-specific symptoms, no use of emergency medical services, no ST-segment deviation, chronic kidney disease, and Global Registry of Acute Coronary Events score &gt;140.

Conclusion

Early invasive strategy based on the StC time improves all-cause mortality in patients with NSTEMI.

Funding Acknowledgement

Type of funding sources: None.

Examining the effect of COVID-19 pandemic on exercise behavior and perceived academic stress among U.S. college students

Objective: The aim of this study was to capture the impact of COVID-19 on exercise behavior in U.S. college students. Exercise behaviors and perceived academic stress were examined from pre-COVID-19 (January-March 2020) and early-COVID-19 (April-July 2020) to continued-COVID-19 times (August-October 2020). Participants: One hundred and thirty-two participants completed the online questionnaires retrospectively. Methods: Two-way analyses of variance were used to examine exercise behaviors and academic stress perception over time between genders. Results: Participants spent much time in sedentary behavior and an increase in academic stress was evident in learning during the early-COVID-19 period. The time spent in sedentary behavior was reduced, but the stress involving coursework remained during the continued-COVID period. The impact of the COVID pandemic was observed to be universal across sex groups. Conclusions: Universities should consider how to support physical and mental health during lockdown and extended closure due to a pandemic.

Group B Streptococcus (GBS) colonisation is dynamic over time, whilst GBS capsular polysaccharides-specific antibody remains stable

Group B Streptococcus (GBS) is a leading cause of adverse pregnancy outcomes due to invasive infection. This study investigated longitudinal variation in GBS rectovaginal colonization, serum and vaginal GBS capsular polysaccharide (CPS)-specific antibody levels. Non-pregnant women were recruited in the UK and were sampled every 2 weeks over a 12-week period. GBS isolates were taken from recto-vaginal swabs and serotyped by polymerase chain reaction. Serum and vaginal immunoglobulin G (IgG) and nasal immunoglobulin A (IgA) specific to CPS were measured by Luminex, and total IgG/A by ELISA. Seventy women were enrolled, of median age 26. Out of the 66 participants who completed at least three visits: 14/47 (29.8%) women that were GBS negative at screening became positive in follow-up visits and 16/19 (84.2%) women who were GBS positive at screening became negative. There was 50% probability of becoming negative 36 days after the first positive swab. The rate of detectable GBS carriage fluctuated over time, although serum, vaginal, and nasal CPS-specific antibody levels remained constant. Levels of CPS-specific antibodies were higher in the serum of individuals colonized with GBS than in non-colonized, but similar in the vaginal and nasal mucosa. We found correlations between antibody levels in serum and the vaginal and nasal mucosa. Our study demonstrates the feasibility of elution methods to retrieve vaginal and nasal antibodies, and the optimization of immunoassays to measure GBS-CPS-specific antibodies. The difference between the dynamics of colonization and antibody response is interesting and further investigation is required for vaccine development.

957 THE USE OF IPADS AS PART OF PERSON CENTERED CARE IN A TEACHING HOSPITAL IN SINGAPORE

The elderly patients are currently the main occupants of acute hospital beds and this trend will likely increase as the world ages. The elderly patients with cognitive issues frequently have behavioural symptoms which may be challenging for the care staff to manage, especially the staff who have not been formally trained in Gerontology. The use of restraints for this group of vulnerable patients should be discouraged as restraints can cause harmful effects.

The use of iPads as a non pharmacological strategy for managing the behavioural symptoms among the elderly in-patients with cognitive issues was effective in reducing agitation, with an improvement in mood and sundown symptoms. The patients were actively and meaningfully engaged with their iPads during therapy.

The nursing staff too, benefited from iPads as a novel therapy for their elderly in-patients with cognitive issues in providing cognitive and social stimulations, which they had no time to provide for. While the patients showed improvement in their behavioural symptoms, the nurses’ stress levels reduced with improved self-reported job satisfaction.

Impact of changes in tricuspid regurgitation on clinical outcomes following mitral valve teer compared to guideline-directed medical therapy: a sub-analysis of the COAPT trial

Funding Acknowledgements

Type of funding sources: None.

OnBehalf

Cardiovascular Outcomes Assessment of the MitraClip Percutaneous Therapy for Heart Failure Patients with Functional Mitral Regurgitation (COAPT)

Background

Prior studies suggest tricuspid regurgitation (TR) diminishes/resolves following mitral valve surgery and thus do not require treatment and may not influence outcomes.

Purpose

  We sought to evaluate the change in TR (ΔTR) and its association with outcomes after transcatheter edge-to-edge repair (TEER) compared with guideline-directed medical therapy (GDMT) in the COAPT trial.

Methods

Patients from the COAPT trial with echo core lab TR assessment at baseline and 30-day follow-up (n = 504) were included and divided into 2 groups: those whose TR worsened (ΔTR-INC) and those with no change or improvement in TR (ΔTR-SAME/DEC).  Two-year composite endpoints of death or heart failure hospitalization (HFH) and the individual components were analyzed, after excluding events occurring within the first 30 days.

Results

ΔTR-SAME/DEC occurred in 430 pts (228 TEER, 202 GDMT) while ΔTR-INC was noted in 74 pts (38 TEER, 36 GDMT) (Figure 1A). From 30 days to 2 years, ΔTR-INC pts had a higher rate of the composite outcome of death or HFH compared with ΔTR-SAME/DEC (p = 0.006, Figure 1B). Both 2-year death (HR 1.52, 95% CI 1.01-2.27; p = 0.04) and HFH (HR 1.52, 95% CI 1.04-2.22; p = 0.03) were associated with ΔTR-INC. Assessed by treatment group (Figure 1C and 1D), the relationship between ΔTR-INC and composite death or HFH was significant in GDMT alone pts (HR 1.86, 95% CI 1.21-2.86) but not in TEER pts (HR 1.33, 95% CI 0.79-2.23), although interaction testing demonstrated consistency between the two treatments  (Pint = 0.31). 

Conclusions

Worsening TR at 30 days occurred in ∼15% of pts in the COAPT trial whether they were treated with TEER or GDMT alone. DTRINC was associated with increased death and HFH during 2-year follow-up. Abstract Figure 1

Development of postbiotics by whey bioconversion with Enterococcus faecalis M157 KACC81148BP and Lactococcus lactis CAU2013 KACC81152BP for treating periodontal disease and improving gut health

This study developed postbiotics with whey bioconversion product produced by Enterococcus faecalis M157 KACC 81148BP, and mixed whey bioconversion products produced by E. faecalis M157 KACC 81148BP and Lactococcus lactis ssp. lactis CAU2013 KACC 81152BP to alleviate periodontitis (PD) and to improve gut health. The powdered whey bioconversion product (EF) produced by E. faecalis M157 KACC 81148BP, mixed whey bioconversion products (EF+LL) from E. faecalis M157 KACC 81148BP and L. lactis CAU2013 KACC 81152BP, and phosphate-buffered saline (PBS; control) were administered orally to PD-induced rats for 8 wk. Infiltration of inflammatory cells and epithelial proliferation in periodontal tissue were found in control, but the lesions were reduced in PD+EF group (administration of EF to PD-induced rats), and no lesions were observed in PD+EF+LL group (administration of EF+LL to PD-induced rats). The bone loss volumes in PD+EF and PD+EF+LL groups were lower than in control. Cytokine production levels related to inflammation were lower and antioxidative stress markers were higher in PD+EF and PD+EF+LL groups than in control for both periodontal tissue and gut. The ratios of Lactobacillus spp. in gut microbiome of PD+EF and PD+EF+LL groups were higher than in control. These results indicate that the whey bioconversion product produced by E. faecalis M157 KACC 81148BP, and mixed whey bioconversion products produced by E. faecalis M157 KACC 81148BP and L. lactis CAU2013 KACC 81152BP are effective on relieving periodontitis and improving the gut health.

Slow oxidation of magnetite nanoparticles elucidates the limits of the Verwey transition

Magnetite (Fe3O4) is of fundamental importance for the Verwey transition near TV = 125 K, below which a complex lattice distortion and electron orders occur. The Verwey transition is suppressed by chemical doping effects giving rise to well-documented first and second-order regimes, but the origin of the order change is unclear. Here, we show that slow oxidation of monodisperse Fe3O4 nanoparticles leads to an intriguing variation of the Verwey transition: an initial drop of TV to a minimum at 70 K after 75 days and a followed recovery to 95 K after 160 days. A physical model based on both doping and doping-gradient effects accounts quantitatively for this evolution between inhomogeneous to homogeneous doping regimes. This work demonstrates that slow oxidation of nanoparticles can give exquisite control and separation of homogeneous and inhomogeneous doping effects on the Verwey transition and offers opportunities for similar insights into complex electronic and magnetic phase transitions in other materials.

Using group concept mapping software to develop a conceptual framework of left ventricular assist device recipients' experiences

Background

Advanced Heart failure (AHF) carries a high mortality rate. Heart transplantation is one therapeutic option, but low donation rates limits its availability. A left ventricular assist device (LVAD) is an alternative therapy which helps relieve symptoms, while improving prognosis and quality of life. However, lack of donors also means that the LVAD becomes a destination therapy by default.(1) Living with an LVAD requires significant psychological, social and physical adaptation for the recipients' and their families.(2) Patient reported outcome measures (PROMs) are one way of capturing these concerns and ongoing problems. Discussions with a patient and public involvement group found a range of issues not currently captured by available PROMS.

Aim

To develop a conceptual framework which reflects the experiences of LVAD recipients' and evaluate their importance for inclusion in PROMs using a research web platform.

Method

Participants were recruited from a regional transplant centre which covers a wide geographical area in the UK. Ethical approval was obtained and participants were recruited through routine LVAD clinics. Group concept mapping (GCM) is a semi-quantitative mixed methods approach that can be used to capture and quantify recipients' experiences.(3) Groupwisdom concept mapping software was used as the electronic data collection platform.(4) GCM consists of 3 stages: statement generation, thematic statement sorting, and rating statements for importance, relevance and frequency of impact. Multidimensional scaling and hierarchical cluster analysis produces visual representations of recipients' experiences as a points and cluster map, and scoring of statements produces relative importance of items across the clusters.

Results

18 LVAD recipients consented to take part. 101 items and 9 clusters were generated. Clusters represented: Activities; Partner/family dependency; Travel; Mental well-being; LVAD challenges; Equipment and clothing; Physical and cognitive limitations; Restrictions, and LVAD positives. LVAD Positives and LVAD restrictions were rated high for frequency, relevance and importance. Physical and cognitive limitations was rated high for importance and frequency. Equipment was rated high for relevance and frequency, and Challenges was rated high for relevance.

Conclusion

GCM and the online software is a useful tool for developing a conceptual framework and mapping key areas of importance for LVAD recipients, especially, when prioritising important patient reported outcome domains for use in clinical practice, future research and design evolution. Using an electronic platform allowed us to reach participants dispersed over a wide geographical area.

Funding Acknowledgement

Type of funding sources: Other. Main funding source(s): British Heart FoundationNational Institute for Health Research Cluster Rating Map for Importance

Left ventricular assist device therapy improves severe secondary mitral regurgitation without mitral valve repair

Background

Severe secondary mitral regurgitation (MR) worsens prognosis in patients with medically managed heart failure (HF). In patients treated by left ventricular assist device (LVAD), it is unclear whether severe MR should be corrected at time of LVAD implantation.

Purpose

To evaluate impact of LVAD therapy on severe and non-severe secondary MR over 1 year.

Methods

Retrospective single centre study of consecutive patients who underwent HeartMate (HM)2 or HM3 LVAD implantation between January 2011 and March 2020.

Results

Of 155 patients, 20 were excluded due to LVAD exchange (n=10), mitral valve repair (n=1), or inaccessible pre-LVAD echocardiography (n=9). Based on multiparametric grading, 29/135 patients had severe secondary MR and 106/135 had non-severe secondary MR (including none). Severe MR patients were more often female [10/29 (34%) vs 11/106 (10%); p=0.002] but were of similar age (54±12 vs 55±9 years; p=0.624), size (27±5 vs 27±4 kg/m2; p=1.0), with equivalent renal function (53±22 vs 55±20 ml/min/1.73m2; p=0.641) and median pre-operative NT-proBNP [4076 (IQR 206–5438) vs 4914 (IQR 2706–7518) ng/L; p=0.488]. There were similar proportions of patients with ischaemic aetiology [16/29 (55%) vs 66/106 (62%); p=0.488) and those receiving HM2 [11/29 (38%) vs 32/106 (30%)] and HM3 [18/29 (62%) vs 74/106 (70%); p=0.575] LVAD. Echocardiography before LVAD implantation demonstrated similar left ventricular (LV) size (LV end-diastolic volume: 133±44 vs 118±50ml/m2; p=0.145, end-systolic volume: 107±41 vs 96±59ml/m2; p=0.348) and LV ejection fraction (17±9 vs 17±7%; p=1.0). Severe MR patients had significantly greater (p&lt;0.001) MR by proximal isovolumetric surface area (0.93±0.27 vs 0.60±0.16cm), vena contracta (0.79±0.32 vs 0.57±0.18cm), regurgitant volume (47±25 vs 24±12ml), and fraction (54±15 vs 37±13%). Follow-up (f/u) echocardiography was performed at a median 222 days (range 356 days). Patients who received cardiac transplantation before f/u echocardiography were excluded. Relative severities of MR at f/u were: none = 12 (46%), mild = 8 (31%), moderate = 5 (19%), severe = 1 (4%) amongst patients with severe MR pre-LVAD, and none = 55 (58%), mild = 26 (27%), moderate = 13 (14%), severe = 1 (1%) amongst patients with non-severe MR pre-LVAD. At 1-year, after excluding all patients who underwent cardiac transplantation (severe MR n=4; non-severe MR n=2), rates of HF hospitalisation [5/25 (20%) vs 16/104 (15%); p=0.575] and all-cause mortality [2/25 (18%) vs 22/104 (21%); p=0.129)] were similar, irrespective of pre-LVAD MR severity. No patient who died during follow-up had severe MR prior to death.

Conclusion

LVAD improves severe secondary MR in 96% of cases, resulting in 1-year rates of HF hospitalisation and mortality similar to patients without severe MR pre-LVAD. These data suggest mitral valve surgery at time of LVAD implantation is not warranted.

Funding Acknowledgement

Type of funding sources: None.

Longitudinal evaluation of laboratory-based serological assays for SARS-CoV-2 antibody detection

Serological assays for SARS-CoV-2 infection are now widely available for use in diagnostic laboratories. Limited data are available on the performance characteristics in different settings, and at time periods remote from the initial infection. Validation of the Abbott (Architect SARS-CoV-2 IgG), DiaSorin (Liaison SARS-CoV-2 S1/S2 IgG) and Roche (Cobas Elecsys Anti-SARS-CoV-2) assays was undertaken utilising 217 serum samples from 131 participants up to 7 months following COVID-19 infection. The Abbott and DiaSorin assays were implemented into routine laboratory workflow, with outcomes reported for 2764 clinical specimens. Sensitivity and specificity were concordant with the range reported by the manufacturers for all assays. Sensitivity across the convalescent period was highest for the Roche at 95.2-100% (95% CI 81.0-100%), then the DiaSorin at 88.1-100% (95% CI 76.0-100%), followed by the Abbott 68.2-100% (95% CI 53.4-100%). Sensitivity of the Abbott assay fell from approximately 5 months; on this assay paired serum samples for 45 participants showed a significant drop in the signal-to-cut-off ratio and 10 sero-reversion events. When used in clinical practice, all samples testing positive by both DiaSorin and Abbott assays were confirmed as true positive results. In this low prevalence setting, despite high laboratory specificity, the positive predictive value of a single positive assay was low. Comprehensive validation of serological assays is necessary to determine the optimal assay for each diagnostic setting. In this low prevalence setting we found implementation of two assays with different antibody targets maximised sensitivity and specificity, with confirmatory testing necessary for any sample which was positive in only one assay.

Modeling Clinical Responses to Targeted Therapies by Patient-Derived Organoids of Advanced Lung Adenocarcinoma

PURPOSE

Patient-derived organoids (PDO) of lung cancer has been recently introduced, reflecting the genomic landscape of lung cancer. However, clinical relevance of advanced lung adenocarcinoma organoids remains unknown. Here, we examined the ability of PDOs to predict clinical responses to targeted therapies in individual patients and to identify effective anticancer therapies for novel molecular targets.

EXPERIMENTAL DESIGN

Eighty-four organoids were established from patients with advanced lung adenocarcinoma. Formalin-fixed, paraffin-embedded tumor specimens from corresponding patients were analyzed by whole-exome sequencing (n = 12). Organoids were analyzed by whole-exome sequencing (n = 61) and RNA sequencing (n = 55). Responses to mono or combination targeted therapies were examined in organoids and organoid-derived xenografts.

RESULTS

PDOs largely retained somatic alterations including driver mutations of matching patient tumors. PDOs were able to recapitulate progression-free survival and objective responses of patients with non-small cell lung cancer receiving clinically approved tyrosine kinase inhibitors. PDOs recapitulated activity of therapeutic strategies under clinical investigation. YUO-071 harboring an EGFR exon 19 deletion and a BRAF G464A mutation and the matching patient responded to dabrafenib/trametinib combination therapy. YUO-004 and YUO-050 harboring an EGFR L747P mutation was sensitive to afatinib, consistent with the response in the matching patient of YUO-050. Furthermore, we utilized organoids to identify effective therapies for novel molecular targets by demonstrating the efficacy of poziotinib against ERBB2 exon 20 insertions and pralsetinib against RET fusions.

CONCLUSIONS

We demonstrated translational relevance of PDOs in advanced lung adenocarcinoma. PDOs are an important diagnostic tool, which can assist clinical decision making and accelerate development of therapeutic strategies.