Regulation of Exciton Effects in Functionalized Conjugated Polymers by B-N Lewis Pairs for Visible-Light Photocatalysis.

Strong excitonic effects are common in organic conjugated polymer semiconductors, severely hindering the generation of free charge carriers for conducting photocatalysis. Therefore, exploring new channels to modulate exciton dissociation in polymers is far-reaching in facilitating photocatalysis. A series of B-N Lewis pair functionalized conjugated polymers have been developed to minimize exciton effects by modulating charge transfer pathways. Theoretical studies have shown that introducing B-N Lewis pairs can dramatically increase the distance of charge transfer (D index) and the amount of electron transfer and reduce the Coulomb attraction energy (EC), which contributes to breaking the equilibrium of the coexistence of excitons and charge carriers. Further experimental results show that the singlet excitons are efficiently dissociated into more free-charge carriers under photoexcitation to participate in surface reactions. The optimized polymer PyPBM shows an exponential increase in photocatalytic hydrogen and hydrogen peroxide production performance by visible light illumination.

Multidimensional Coherent Spectroscopy of Molecular Polaritons: Langevin Approach.

We present a microscopic theory for nonlinear optical spectroscopy of N molecules in an optical cavity. Using the Heisenberg-Langevin equation, an analytical expression is derived for the time- and frequency-resolved signals accounting for arbitrary numbers of vibrational excitations. We identify clear signatures of the polariton-polaron interaction from multidimensional projections of the signal, e.g., pathways and timescales. Cooperative dynamics of cavity polaritons against intramolecular vibrations is revealed, along with a crosstalk between long-range coherence and vibronic coupling that may lead to localization effects. Our results further characterize the polaritonic coherence and the population transfer that is slower.

Nitrogen supply alleviates seed yield reduction by improving the morphology and carbon metabolism of pod walls in shaded rapeseed.

Shading significantly affects rapeseed yield, while reasonable nitrogen (N) application has efficiency gains. However, the functions and mechanisms of N are not fully established for shaded rapeseed plants. Therefore, we conducted a 2-year field experiment to study the effect of N on pod wall morphology and carbon metabolism of shaded rapeseed. Two varieties, three N rates (120 [N1], 240 [N2], and 360 [N3] kg hm-2 ) and two light intensities (100 and 70% light transmission) from 10 to 35 days after the end of flowering were set as experimental parameters. Shading decreased the pod wall chlorophyll content, ribulose 1,5-bisphosphate carboxylase (Rubisco) activity and glucose content at 25 and 35 days after flowering (DAF). Decreased sucrose synthase (SuSy) and sucrose phosphate synthase activity caused by shading reduced sucrose and fructose content. They are responsible for the decline in the 1000-seed weight and a 22.1-37.6% decline in seed yield. More N under shading promoted pod elongation and pigment content, improved chloroplast ultrastructure, increased Rubisco and SuSy activity at 35 DAF, thus contributing to pod wall photosynthesis and fructose and glucose levels in shaded rapeseed plants. Similar trends were observed in pod number, pod weight, and seed weight, while the greatest increase in seed/wall ratio was observed under N2 for shaded rapeseed plants. The results indicated that N can reduce the yield difference between different light conditions and balance partitioning and conversion of photoassimilates in pod wall, but avoid applying an excessive amount of nitrogen.

Ghost translation: an end-to-end ghost imaging approach based on the transformer network.

Artificial intelligence has recently been widely used in computational imaging. The deep neural network (DNN) improves the signal-to-noise ratio of the retrieved images, whose quality is otherwise corrupted due to the low sampling ratio or noisy environments. This work proposes a new computational imaging scheme based on the sequence transduction mechanism with the transformer network. The simulation database assists the network in achieving signal translation ability. The experimental single-pixel detector's signal will be 'translated' into a 2D image in an end-to-end manner. High-quality images with no background noise can be retrieved at a sampling ratio as low as 2%. The illumination patterns can be either well-designed speckle patterns for sub-Nyquist imaging or random speckle patterns. Moreover, our method is robust to noise interference. This translation mechanism opens a new direction for DNN-assisted ghost imaging and can be used in various computational imaging scenarios.

Hierarchical functional nanoparticles boost osteoarthritis therapy by utilizing joint-resident mesenchymal stem cells.

Utilization of joint-resident mesenchymal stem cells (MSC) to repair articular cartilage is a promising strategy in osteoarthritis (OA) therapy but remains a considerable research challenge. Here, hierarchical targeting and microenvironment responsive peptide functionalized nanoparticles (NPs) are used to achieve cartilage repair in situ. Ultrasmall copper oxide (CuO) NPs are conjugated with type 2 collagen and MSC dual-targeting peptide (designated WPV) with a matrix metalloproteinase 2 (MMP-2)-sensitive sequence as a spacer to achieve hierarchical targeting. Guided by this peptide, WPV-CuO NPs initially penetrate cartilage and subsequently expose the inner MSC-targeted peptide to attract MSCs through MMP-2 clearance. CuO further promotes chondrogenesis of MSCs. In an anterior cruciate ligament transection rat model, intraarticular injection of WPV-CuO NPs induces significant reduction of cartilage destruction. The therapeutic mechanism involves inhibition of the PI3K/AKT/mTOR pathway, as determined via transcriptome analysis. In conclusion, a novel therapeutic strategy for OA has been successfully developed based on localized MSC recruitment and cartilage repair without transplantation of exogenous cells or growth factors.

Sub-Rayleigh second-order correlation imaging using spatially distributive colored noise speckle patterns.

We present a novel method, to our knowledge, to synthesize non-trivial speckle patterns that can enable sub-Rayleigh second-order correlation imaging. The speckle patterns acquire a unique anti-correlation in the spatial intensity fluctuation by introducing the blue noise distribution on spatial Fourier power spectrum to the input light fields through amplitude modulation. Illuminating objects with the blue noise speckle patterns can lead to a sub-diffraction limit imaging system with a resolution more than three times higher than first-order imaging, which is comparable to the resolving power of ninth order correlation imaging with thermal light. Our method opens a new route towards non-trivial speckle pattern generation by tailoring amplitudes in spatial Fourier power spectrum of the input light fields and provides a versatile scheme for constructing sub-Rayleigh imaging and microscopy systems without invoking complicated higher-order correlations.

Osteoarthritic infrapatellar fat pad aggravates cartilage degradation via activation of p38MAPK and ERK1/2 pathways.

OBJECTIVE: This study aimed to investigate the biochemical effects of osteoarthritic infrapatellar fat pad (IPFP) on cartilage and the underlying mechanisms. METHODS: Human IPFP and articular cartilage were collected from end-stage osteoarthritis (OA) patients during total knee arthroplasty. IPFP-derived fat-conditioned medium (FCM) was used to stimulate human primary chondrocytes and cartilage explants. Functional effect of osteoarthritic IPFP was explored in human primary chondrocytes and articular cartilage in vitro and ex vivo. Activation of relative pathways and its effects on chondrocytes were assessed through immunoblotting and inhibition experiments, respectively. Neutralization test was performed to identify the main factors and their associated pathways responsible for the effects of IPFP. RESULTS: Osteoarthritic IPFP-derived FCM significantly induced extracellular matrix (ECM) degradation in both human primary chondrocytes and cartilage explants. Several pathways, such as NF-κB, mTORC1, p38MAPK, JNK, and ERK1/2 signaling, were significantly activated in human chondrocytes with osteoarthritic IPFP-derived FCM stimulation. Interestingly, inhibition of p38MAPK and ERK1/2 signaling pathway could alleviate the detrimental effects of FCM on chondrocytes, while inhibition of other signaling pathways had no similar results. In addition, IL-1ß and TNF-α instead of IL-6 in osteoarthritic IPFP-derived FCM played key roles in cartilage degradation via activating p38MAPK rather than ERK1/2 signaling pathway. CONCLUSION: Osteoarthritic IPFP induces the degradation and inflammation of cartilage via activation of p38MAPK and ERK1/2 pathways, in which IL-1ß and TNF-α act as the key factors. Our study suggests that modulating the effects of IPFP on cartilage may be a promising strategy for knee OA intervention.

Anesthesia Service Use During Outpatient Gastroenterology Procedures Continued to Increase From 2010 to 2013 and Potentially Discretionary Spending Remained High.

OBJECTIVES: Previous studies have identified an increasing number of gastroenterology (GI) procedures using anesthesia services to provide sedation, with a majority of these services delivered to low-risk patients. The aim of this study was to update these trends with the most recent years of data. METHODS: We used Medicare and commercial claims data from 2010 to 2013 to identify GI procedures and anesthesia services based on CPT codes, which were linked together using patient identifiers and dates of service. We defined low-risk patients as those who were classified as ASA (American Society of Anesthesiologists) physical status class I or II. For those patients without an ASA class listed on the claim, we used a prediction algorithm to impute an ASA physical status. RESULTS: Over 6.6 million patients in our sample had a GI procedure between 2010 and 2013. GI procedures involving anesthesia service accounted for 33.7% in 2010 and 47.6% in 2013 in Medicare patients, and 38.3% in 2010 and 53.0% in 2013 in commercially insured patients. Overall, as more patients used anesthesia services, total anesthesia service use in low-risk patients increased 14%, from 27,191 to 33,181 per million Medicare enrollees. Similarly, we observed a nearly identical uptick in commercially insured patients from 15,871 to 22,247 per million, an increase of almost 15%. During 2010-2013, spending associated with anesthesia services in low-risk patients increased from US$3.14 million to US$3.45 million per million Medicare enrollees and from US$7.69 million to US$10.66 million per million commercially insured patients. CONCLUSIONS: During 2010 to 2013, anesthesia service use in GI procedures continued to increase and the proportion of these services rendered for low-risk patients remained high.

Primary care medical home experience and health-related quality of life among adult medicaid patients with type 2 diabetes.

PURPOSE: To examine whether patient-reported indicators of medical home performance are associated with health-related quality of life (HRQOL) among adults with type 2 diabetes. METHODS: Cross-sectional survey of 540 patients with Medicaid insurance and type 2 diabetes in Los Angeles County. The Primary Care Assessment Tool was used to measure seven features of medical home performance. The EuroQol EQ-5D-3L (EQ-5D) was used to measure HRQOL. RESULTS: Higher total medical home performance was correlated with better overall HRQOL. A one-point change in total medical home score was associated with a 0.06-point higher score on the EQ-5D index [95 % confidence interval (CI): 0.01-0.11], which is a clinically meaningful difference. The total score was also significantly associated with a lower likelihood of problems on one domain of the EQ-5D (pain). Longitudinality was the only medical home feature associated with better general health status (ordered odds ratio = 1.78; 95 % CI: 1.04-3.03). The positive relationship of medical home with the EQ-5D appears to be present predominantly among women. CONCLUSION: Overall medical home experience is favorably associated with HRQOL among vulnerable adult patients with type 2 diabetes. Provider efforts to improve the overall medical home experience for patients may contribute to improvements in HRQOL.

Bionic Design and Adsorption Performance Analysis of Vacuum Suckers.

This study addresses the problem that the traditional method is not effective in improving the adsorption performance of vacuum suckers. From the perspective of bionics, the adsorption performance of bionic suckers based on the excellent adsorption of the abalone abdominal foot was studied. A bionic sucker was designed by extracting the sealing ring structure of the abdominal foot tentacle. The bionic sucker was subjected to tensile experiments using an orthogonal experimental design, and the adsorption of the bionic sucker was simulated and analyzed to explore its adsorption mechanism. The results show that the primary and secondary factors affecting the adsorption of the sucker are the number of sealing rings, the width of sealing rings and the spacing of sealing rings. At 60% vacuum, the bionic sucker with two sealing rings, a 1.5 mm sealing ring width and 3 mm sealing ring spacing has the largest adsorption force, and its maximum adsorption force is 15.8% higher than that of the standard sucker. This study shows that the bionic sucker design can effectively improve the adsorption performance of the sucker. The bionic sucker had a different stress distribution on the sucker bottom, which resulted in greater Mises stress in the sealing ring and the surrounding area, while the Mises stress in the central area of the sucker was smaller.

Machine learning to guide the use of plasma technology for antibiotic degradation.

Antibiotics are misused and discharged into environmental water, posing a constant potential threat to the ecosystem. Utilising plasma's physical and chemical effects to remove antibiotics has emerged as a promising wastewater treatment technology. However, the complexity and high cost of reactor configurations represent significant limitations to the practical application of this technology. Furthermore, evaluating the degradation efficiency of antibiotics necessitates using costly and sophisticated testing instruments, coupled with time-consuming and labour-intensive experiments. The present study developed a generalised model using machine learning algorithms to predict the removal efficiency of antibiotics by a plasma system. Of the eight machine learning algorithms constructed, the ensemble model XGBoost exhibited the highest prediction accuracy, as indicated by a Pearson correlation coefficient of 0.943. This correlation indicates a strong relationship between the predicted removal rates and the experimental values. Moreover, the accuracy of the prediction was enhanced through the utilisation of a multi-model stacking approach. A further quantitative assessment of the key factors affecting the efficiency of the plasma process, and their synergistic effects, is provided by the interpretable analysis of the model's behaviour. It is anticipated that the results will facilitate the design of efficient plasma systems, reduce the need for extensive experimental screening, and improve practical applications in the removal of antibiotic contamination. This provides an informative view of the applications of plasma technology, opening the way for new environmental research questions.

Real-World Patterns and Economic Burden Associated With Treatment Failure With Advanced Therapies in Patients With Moderate-to-Severe Ulcerative Colitis.

Background: Some patients lose response during treatment for moderate-to-severe ulcerative colitis (UC). We aimed to characterize real-world treatment failure patterns and associated economic burdens during use of first-line advanced therapies for UC. Methods: IBM MarketScan Commercial and Medicare Supplemental Databases were used to identify adults initiating ≥ 1 advanced therapy for UC (January 1, 2010-September 30, 2019). Treatment failure was defined as augmentation with non-advanced therapy, discontinuation, dose escalation/interval shortening, failure to taper corticosteroids, UC-related surgery, or UC-related urgent care ≤ 12 months after treatment initiation. The index date was the date of treatment failure (treatment failure cohort) or 12 months after treatment initiation (persistent cohort). Treatment failure rates were assessed using Kaplan-Meier analyses. All-cause and UC-related healthcare resource utilization (HCRU) and costs 12 months post-index were also assessed. Results: Analysis of treatment failure patterns included data from 6745 patients; HCRU and cost analyses included data from 5302 patients (treatment failure cohort, n = 4295; persistent cohort, n = 1007). In the overall population, 75% experienced treatment failure within the first 12 months (median: 5.1 months). Augmentation with non-advanced therapy (39%) was the most common first treatment failure event. The treatment failure cohort had significantly (P < .001) higher mean costs than the persistent cohort (all-cause, $74 995 vs $56 169; UC-related, $57 096 vs $47 347) mainly attributed to inpatient admissions and outpatient visits. Dose escalation/interval shortening accounted for the highest total costs ($101 668) across treatment failure events. Conclusions: Advanced therapies for moderate-to-severe UC are associated with high rates of treatment failure and significant economic burden. More efficacious and durable treatments are needed.

Extracellular Vesicles in Infrapatellar Fat Pad from Osteoarthritis Patients Impair Cartilage Metabolism and Induce Senescence.

Infrapatellar fat pad (IPFP) is closely associated with the development and progression of knee osteoarthritis (OA), but the underlying mechanism remains unclear. Here, it is find that IPFP from OA patients can secret small extracellular vesicles (sEVs) and deliver them into articular chondrocytes. Inhibition the release of endogenous osteoarthritic IPFP-sEVs by GW4869 significantly alleviated IPFP-sEVs-induced cartilage destruction. Functional assays in vitro demonstrated that IPFP-sEVs significantly promoted chondrocyte extracellular matrix (ECM) catabolism and induced cellular senescence. It is further demonstrated that IPFP-sEVs induced ECM degradation in human and mice cartilage explants and aggravated the progression of experimental OA in mice. Mechanistically, highly enriched let-7b-5p and let-7c-5p in IPFP-sEVs are essential to mediate detrimental effects by directly decreasing senescence negative regulator, lamin B receptor (LBR). Notably, intra-articular injection of antagomirs inhibiting let-7b-5p and let-7c-5p in mice increased LBR expression, suppressed chondrocyte senescence and ameliorated the progression of experimental OA model. This study uncovers the function and mechanism of the IPFP-sEVs in the progression of OA. Targeting IPFP-sEVs cargoes of let-7b-5p and let-7c-5p can provide a potential strategy for OA therapy.

Single-cell atlas of human infrapatellar fat pad and synovium implicates APOE signaling in osteoarthritis pathology.

The infrapatellar fat pad (IPFP) and synovium play essential roles in maintaining knee joint homeostasis and in the progression of osteoarthritis (OA). The cellular and transcriptional mechanisms regulating the function of these specialized tissues under healthy and diseased conditions are largely unknown. Here, single-cell and single-nuclei RNA sequencing of human IPFP and synovial tissues were performed to elucidate the cellular composition and transcriptional profile. Computational trajectory analysis revealed that dipeptidyl peptidase 4+ mesenchymal cells function as a common progenitor for IPFP adipocytes and synovial lining layer fibroblasts, suggesting that IPFP and synovium represent an integrated tissue unit. OA induced a profibrotic and inflammatory phenotype in mesenchymal lineage cells with biglycan+ intermediate fibroblasts as a major contributor to OA fibrosis. Apolipoprotein E (APOE) signaling from intermediate fibroblasts and macrophages was identified as a critical regulatory factor. Ex vivo incubation of human cartilage with soluble APOE accelerated proteoglycan degeneration. Inhibition of APOE signaling by intra-articular injection of an anti-APOE neutralizing antibody attenuated the progression of collagenase-induced OA in mice, demonstrating a detrimental effect of APOE on cartilage. Our studies provide a framework for designing further therapeutic strategies for OA by describing the cellular and transcriptional landscape of human IPFP and synovium in healthy versus OA joints.

Race/ethnicity, insurance, income and access to care: the influence of health status.

OBJECTIVES: To examine health care access disparities with regard to health status and presence of functional limitations, a common measure of disability and multimorbidity, after controlling for individual's race/ethnicity, insurance status and income in the U.S. using the latest survey data. METHODS: Using data from the 2009 Family Core component of the National Health Interview Survey (NHIS), we examined six measures of access to care in the twelve months prior to the interview. Covariates included self-perceived health status and the presence of functional limitations, race/ethnicity, insurance status, income, and other socioeconomic characteristics. Multiple logistic regressions were used to examine the associations. RESULTS: People with functional limitations or worse health status experience greater barriers to access. Insurance status was the single factor that was associated with all six measures of access. Disparities among racial/ethnic groups in most access indicators as well as income levels were insignificant after taking into account individuals' health status measures. CONCLUSIONS: Interventions to expand insurance coverage and the Patient Protection and Affordable Care Act are expected to contribute to reducing disparities in access to care. However, to further improve access to care, emphasis must be placed on those with poorer health status and functional limitations.

Chinese primary care providers and motivating factors on performance.

BACKGROUND: China launched its new health care reform in 2009. One of its goals is to improve primary care system and strengthen primary care workforce. Although it has been studied internationally, motivating factors for primary care workforce have not been examined in China. AIM: To provide an overview of major performance motivating factors for primary care providers (PCPs) in China and examine associations between these factors and individual and practice setting characteristics. METHODS: Data for the study were from the 2011 China Primary Care Workforce Survey that provides the most current assessment of community-based PCPs. Outcome measures were scores indicating performance improvement due to 11 factors. Covariates representing personal and practice characteristics included age, gender, education, location, types of providers and specialties. Outcomes were compared by PCP category and urban/rural setting. Associations were assessed using logistic regressions. RESULTS: The most important motivating factors for PCPs to improve performance were professional development, training opportunities, living environment, benefits, working conditions and income. There were greater needs for improvement in rural than urban settings, especially in living environment. Types of PCPs were associated with needs for improvement in different factors. There were more needs from nurses and village doctors. CONCLUSIONS: A new and comprehensive incentive mechanism could be designed and implemented in China, which (i) focuses on more professional development opportunities, enhanced training programs and better compensation and benefits and (ii) targets PCPs practicing in different settings.

Field-programmable-gate-array-based digital frequency stabilization of low-phase-noise diode lasers.

We present the comparison of a field-programmable-gate-array (FPGA) based digital servo module with an analog counterpart for the purpose of laser frequency stabilization to a high-finesse optical cavity. The transfer functions of both the digital and analog modules for proportional-integral-derivative control are measured. For the lasers stabilized to the cavity, we measure the singe-sideband power spectral density of fast phase noise by means of an optical beat with filtered light transmitted through the cavity. The comparison between the digital and analog modules is performed for two low-phase-noise diode lasers at 1120 and 665 nm wavelengths. The performance of the digital servo module compares well to the analog one for the lowest attained levels of 30 mrad for the integrated phase noise and 10-3 for the relative noise power. The laser linewidth is determined to be in the sub-kHz regime, only limited by the high-finesse cavity. Our work exploits the versatility of the FPGA-based servo module (STEMlab) when used with open-source software and hardware modifications. We demonstrated that such modules are suitable candidates for remote-controlled low-phase-noise applications in the fields of laser spectroscopy and atomic, molecular, and optical physics.

Nivolumab Plus Chemotherapy for Advanced Gastric, Gastroesophageal Junction, and Esophageal Adenocarcinoma: Analysis of Number Needed To Treat and Number Needed To Harm.

PURPOSE: Nivolumab, a programmed cell death protein (PD)-1 inhibitor, was approved by the US Food and Drug Administration in 2021 advanced/metastatic gastric cancer, gastroesophageal junction cancer, and esophageal adenocarcinoma, in combination with fluoropyrimidine and platinum-based chemotherapy. In the present study, the number needed to treat (NNT) for overall survival (OS), progression-free survival (PFS), and objective response rate (ORR)-and the number needed to harm (NNH) for tolerability outcomes-with nivolumab + chemotherapy versus chemotherapy alone were determined. METHODS: NNT and NNH were calculated as the reciprocal of the risk difference between the two treatment arms, with the 95% CIs calculated as the reciprocals of the upper and lower bounds of the 95% CI of the risk difference, using data from the CheckMate 649 study. FINDINGS: Among all treated patients, the NNTs for OS over 1 and 2 years were 15.15 and 12.05; for PFS, 10.87 and 19.61; and for ORR over the entire trial period, 8.95. The corresponding NNTs in the subgroup with PD-L1 CPS ≥5 were less. The NNH for grade ≥3 treatment-related adverse events (TEAEs) over 1 year among all treated patients was 7.02. IMPLICATIONS: The small estimated NNT values in this study suggest that patients would benefit from nivolumab + chemotherapy, and while the NNH for grade ≥3 TRAEs was small, the NNH for any individual TRAE were large or negative.

Real-World Treatment Patterns and Outcomes Following First-Line Pertuzumab and Trastuzumab Among Patients with HER2+ Metastatic Breast Cancer.

INTRODUCTION: Many patients with human epidermal growth factor receptor-2-positive metastatic breast cancer (HER2+ mBC) require subsequent lines of therapy (LOTs) after being treated with pertuzumab and trastuzumab-based regimens in the first line (1L). Although the efficacy of the second-line (2L) therapies has been demonstrated in clinical trials, the real-world effectiveness of these treatments is understudied. This retrospective cohort study assessed the real-world treatment patterns and outcomes for patients with HER2+ mBC following 1L therapy with pertuzumab and trastuzumab-based regimens in the United States (US) during 2015-2019. METHODS: Adults with HER2+ mBC in the US who initiated 1L pertuzumab and trastuzumab-based regimens between 01/01/2015 and 09/30/2019 and had ≥ 60 days of follow-up after 1L initiation were identified from the IQVIA Oncology Electronic Medical Records database. The regimens utilized in 2L following 1L pertuzumab and trastuzumab-based regimens were described. Median treatment duration and time to treatment failure were reported for 2L based on Kaplan-Meier analyses. RESULTS: Of the 710 eligible patients who received pertuzumab and trastuzumab-based regimens in 1L (median age: 57.0 years [interquartile range: 48.0-65.0]; median follow-up: 20.3 months; median 1L duration: 15.3 months), 222 (31.3%) initiated 2L. The most common regimens in 2L were ado-trastuzumab emtansine (T-DM1)-based regimens (n = 159 [71.6%]), followed by lapatinib-based (n = 21 [9.5%]) and neratinib-based (n = 18 [8.1%]) regimens. The median treatment duration and time to treatment failure were 5.9 (95% CI: 5.0, 8.7) and 8.6 (7.3, 11.5) months, respectively, among patients initiating 2L, and 5.7 (4.7, 7.8) and 7.9 (6.5, 10.0) months among those receiving 2L T-DM1. CONCLUSIONS: Most patients with HER2+ mBC requiring additional treatments after 1L pertuzumab and trastuzumab-based regimens utilized T-DM1 in 2L during 2015-2019. The short median treatment duration and time to treatment failure highlight an unmet need that can potentially be fulfilled by recently approved treatment options.

Real-World Treatment Patterns and Economic Burden Following First-Line Trastuzumab in Patients with Metastatic Gastric Cancer in the USA.

BACKGROUND: Trastuzumab in combination with chemotherapy is the standard first-line (1L) treatment for HER2+ metastatic gastric cancer (mGC) in the USA. OBJECTIVE: This study characterizes the real-world treatment patterns, healthcare resource use (HRU), and costs in patients with HER2+ mGC post-1L trastuzumab before approval of fam-trastuzumab deruxtecan-nxki. PATIENTS AND METHODS: This retrospective study used the IQVIA PharMetrics® Plus Database (October 2014-September 2019) to identify adults with HER2+ mGC who discontinued trastuzumab-based regimens in 1L. Patient characteristics, second-line (2L) treatment patterns, and treatment duration were summarized. HRU and costs before and after discontinuation of 1L trastuzumab-based regimens as well as during 2L treatment were described. RESULTS: Of the 190 HER2+mGC patients who discontinued 1L trastuzumab-based regimens, 136 (71.58%) initiated 2L treatments. Trastuzumab-based regimens were the most common in 2L (50.74%), followed by ramucirumab + paclitaxel (19.85%). The median time to 2L discontinuation was 2.37 months. During a mean follow-up of 9.8 months, mean per-patient-per-month (PPPM) healthcare costs post-1L trastuzumab-based regimens were higher in patients receiving 2L treatment than those without subsequent treatment (US$25,178 vs. US$14,812). The mean PPPM cost during 2L treatment was US$30,838, primarily driven by outpatient infusion costs (US$22,262). CONCLUSIONS: The short duration of 2L treatment observed in this study is consistent with a lack of effective treatments post-1L trastuzumab prior to 2020. Re-use of trastuzumab treatment was common despite its limited efficacy and high treatment cost. The findings highlight the unmet medical needs and substantial burden faced by patients with HER2 +mGC previously treated with trastuzumab.