Citations

Abstract Purpose Large language models (LLMs) have proven performance for certain diagnostic tasks; however, limited studies have evaluated their consistency in recommending appropriate medication regimens for a given diagnosis. Medication management is a complex task that requires synthesis of drug formulation and complete order instructions for safe use. Here, the performance of GPT-4o, an LLM available with OpenAI’s ChatGPT, was tested on 3 medication management tasks. Methods GPT-4o performance was tested on 3 medication tasks: identifying available formulations for a given generic drug name, identifying drug-drug interactions (DDIs) for a given medication regimen, and preparing a medication order for a given generic drug name. For each experiment, the model’s raw text response was captured exactly as returned and evaluated using clinician evaluation in addition to standard LLM metrics, including Term Frequency-Inverse Document Frequency (TF-IDF) vectors, normalized Levenshtein similarity, and Recall-Oriented Understudy for Gisting Evaluation (ROUGE-1/ROUGE-L) F1 score between each response and its reference string. Results For the first task of drug-formulation matching, GPT-4o had 49% accuracy for generic medications being matched to all available formulations, with an average of 1.23 omissions per medication and 1.14 hallucinations per medication. For the second task of drug-drug interaction identification, the accuracy was 54.7% for identifying the DDI pair. For the third task, GPT-4o generated order sentences containing no medication or abbreviation errors in 65.8% of the cases. Conclusion Model performance for basic medication tasks was consistently poor. This evaluation highlights the need for domain-specific training through clinician-annotated datasets and a comprehensive evaluation framework for benchmarking performance.

Abstract Purpose Bevacizumab is an effective treatment for radiation necrosis; dose dependent radiographic and edema response data are lacking. Methods Multicenter, retrospective cohort study of adult patients with primary central nervous system tumors or brain metastases who received bevacizumab for radiation necrosis between June 2021 and July 2024. Patients were grouped by bevacizumab dose (7.5 mg/kg vs 10 mg/kg administered every three weeks). Primary outcome was edema response, assessed by a blinded neuro-oncologist. Secondary outcomes included contrast enhancing disease response, clinical response, adverse events, treatment discontinuation, and re-dosing for recurrent radiation necrosis. Analyses were performed with and without adjustment for tumor type. Results 104 patients were included (7.5 mg/kg, n = 53; 10 mg/kg, n = 51). Edema response differed between dosing groups in unadjusted analyses (p = 0.032), favoring the 7.5 mg/kg cohort; however, this association was attenuated after adjustment for tumor type. Contrast enhancing disease response did not differ between groups in either unadjusted or adjusted analyses (p = 0.43). Clinical response was higher in the 7.5 mg/kg group (65.2% vs 37.8%, p = 0.013). Tumor type differed significantly between cohorts (p < 0.001), with more primary CNS tumors in the 10 mg/kg group. Rates of adverse events, treatment discontinuation, and re-dosing were similar. Conclusions While lower-dose bevacizumab was associated with greater edema reduction in unadjusted analyses, this effect was attenuated after accounting for tumor type. Importantly, 7.5 mg/kg dosing appeared sufficient for achieving edema control and contrast enhancing disease response. These findings support an individualized approach to bevacizumab dosing in radiation necrosis and highlight the need for prospective, tumor-stratified studies.

Abstract Background Bevacizumab is a treatment for radiation necrosis; the optimal dosing remains inadequately studied. Methods Retrospective review of adult patients with primary central nervous system (CNS) tumors or brain metastasis treated with bevacizumab for radiation necrosis from 6/29/2021 to 7/31/2024. Primary outcome was to compare edema response with two different bevacizumab doses: 7.5 mg/kg and 10 mg/kg. Edema response was classified according to the following groups: (1) increase of edema, &gt;105% of baseline; (2) constant edema, 75%-105% of baseline; (3) slight decrease of edema, 25%-75% of baseline; (4) large decrease of edema, &lt;25% of baseline. Results 104 patients were evaluated (median age 59 years, 56% male); 53 patients in the 7.5 mg/kg group and 51 patients in the 10 mg/kg group. Tumor type varied significantly across dosing groups (p &lt; 0.001). In the 7.5 mg/kg group, tumor type was primary CNS (n = 23, 43%), lung (n = 14, 26%), breast (n = 8, 15%), melanoma (n = 4, 8%) and other (n = 4, 8%). In the 10 mg/kg group, tumor type was primary CNS (n = 43, 84%), lung (n = 2, 4%), melanoma (n = 2, 4%) and other (n = 4, 8%). Median number of bevacizumab doses administered was 4. There was a statistically significant difference in distribution of edema response across all response levels favoring bevacizumab 10 mg/kg (p = 0.032). When edema response was dichotomized (large decrease vs other), the difference remained statistically significant (p = 0.015). Conclusion Bevacizumab 10 mg/kg was more efficacious in terms of edema response; this result is impacted by the significantly higher incidence of primary CNS tumors in the 10 mg/kg dosing group.

ABSTRACT Background Higher time in sedentary behavior and insufficient physical activity are very common in bipolar disorder (BD). Whereas physical activity and exercise offer significant benefits across mental health, brain health, and heart health in BD. The International Society for Bipolar Disorders Nutrition and Exercise Task Force (NExT) synthesized evidence to evaluate the impacts of sedentary behavior, physical activity, and exercise on illness course, physical health, and treatment outcomes. Methods A best‐evidence synthesis was conducted using a question‐and‐answer format. We searched PsycINFO, SPORTDiscus, Embase, PubMed, and Web of Science from inception to March 1st, 2026, supplemented by reference lists and existing guidelines. Search terms included combinations of physical activity, exercise, sedentary behavior, and bipolar disorder‐related terms. Results Observational studies show that individuals with BD exhibit significantly higher sedentary behavior and lower physical activity compared to the general population, with notable discrepancies between self‐reported and objective measurements. Evidence on physical activity's protective role against BD onset is mixed, with some prospective and Mendelian randomization studies suggesting reduced risk, while others report bidirectional or null associations. Preliminary findings from clinical trials indicate that exercise improves overall functioning, reduces mood episode frequency and hospitalizations, and alleviates depressive symptoms, with one pilot study showing an 82% antidepressant response rate. Exercise also shows potential to reduce anxiety and improve sleep, though robust data are limited. Conclusions Despite limited high‐quality evidence, physical activity and exercise demonstrate promising physical and mental health benefits for individuals with BD. Future research should prioritize multicenter randomized controlled trials, enhanced assessment tools, and accessible, tailored programs to integrate physical activity into routine BD management.

Introduction Community-acquired pneumonia (CAP) is common and remains the leading infectious cause of death worldwide. Antibiotics remain the mainstay of treatment, but organisms are often not identified, necessitating empirical treatment. Current treatment guidelines recommend combination therapy with beta-lactams and macrolides or monotherapy with fluoroquinolones for non-severe CAP. However, rising antibiotic resistance and safety concerns have led to increased doxycycline use, despite limited evidence supporting its efficacy. Our goal is to conduct a pragmatic, open-label, randomised clinical trial comparing the effectiveness of azithromycin with that of doxycycline in combination with beta-lactam therapy in adult patients hospitalised for CAP. Methods and analysis Patients presenting to the emergency department or directly referred to the hospital with a clinical presentation concerning for CAP and need for hospitalisation are eligible. We plan to enrol 1120 adults hospitalised at six hospitals across four states, including rural, suburban and urban settings and academic and community hospitals. Randomisation will be 1:1 using an electronic health record (EHR)-embedded screening and randomisation tool triggered by the treating clinician’s orders for azithromycin or doxycycline. Outcomes will be ascertained pragmatically via EHR-based data retrieval and will not require additional study visits. Our primary outcome is days alive and out of the hospital through day 28. Secondary outcomes include oxygen-free days; a composite of a need for advanced respiratory support or in-hospital mortality with analyses of each component separately; an ordinal measure of clinical deterioration defined by a prespecified severity scale; and 60-day and 180-day mortality. Safety outcomes are the incidence of Clostridioides difficile infection and QT prolongation. Analyses will follow an intention-to-treat framework, with per-protocol analyses for sensitivity. The primary endpoint will be compared between groups using a stratified van Elteren test, with supportive analyses using proportional odds regression and analysis of covariance adjusted for key covariates. Ethics and dissemination The Mayo Clinic Institutional Review Board reviewed and approved this protocol with a waiver of written consent, requiring verbal consent to be obtained by the clinician initiating the antibiotics (IRB# 24–0 06 503). Findings will be disseminated through peer-reviewed publications and international conference presentations. Trial registration number NCT07164131 .

Abstract Background Isocitrate dehydrogenase-1 (IDH-1) inhibitor ivosidenib and dual-IDH1/2 inhibitor vorasidenib have demonstrated clinical activity in the treatment of IDH-mutant gliomas. We evaluated the efficacy of vorasidenib in patients with prior exposure to ivosidenib. Methods Retrospective review of patients with IDH-mutant glioma treated with vorasidenib who had prior treatment with ivosidenib. Previous treatments, radiographic response, and adverse events were collected and analyzed descriptively. Results Twenty-nine patients (median age 42, 34% female) were evaluated. Tumor types included IDH-mutant astrocytoma (grade 2 n = 9, 31%; grade 3 n = 3, 10%; grade 4 n = 3, 10%) and oligodendroglioma (grade 2 n = 10, 34%; grade 3 n = 4, 14%). Treatments received prior to ivosidenib included surgical resection (n = 23, 79%), radiation (n = 16, 55%), temozolomide (n = 15, 52%), procarbazine, lomustine, vincristine (PCV, n = 2, 7%), bevacizumab (n = 3, 10%), lomustine (n = 2, 7%), and pembrolizumab (n = 1, 3%). Four patients received additional treatment in between ivosidenib and vorasidenib treatment. Ten of 16 (63%) patients who experienced disease progression on ivosidenib achieved stable disease and remain on vorasidenib, while 6 (37%) had continued progression. Eleven patients with stable disease on ivosidenib transitioned to vorasidenib following FDA approval and remained without progression. Two patients who transitioned to vorasidenib due to ivosidenib-related adverse effects (diarrhea and fatigue) experienced symptom resolution and maintained disease stability. Conclusions Vorasidenib demonstrated clinical efficacy in patients with IDH-mutant gliomas previously treated with ivosidenib. Notably, stable patients who transitioned maintained disease stability, while some of those with progressive disease achieved stabilization with vorasidenib. These findings support vorasidenib as a viable therapeutic option following ivosidenib exposure.

Objectives: Consensus clinical criteria for refractory septic shock were recently developed, but the incidence and outcomes with these criteria are unknown. There were two aims: 1) to describe the incidence of refractory septic shock and 2) to assess outcomes of patients with septic shock meeting refractory septic shock criteria compared with those who did not. Design: Multicohort, retrospective study. For aim 1, a descriptive epidemiologic study was designed to ascertain the cumulative incidence of refractory septic shock in patients with septic shock. For aim 2, a cohort study was conducted to compare hospital mortality between patients meeting refractory septic shock clinical criteria compared with those who did not. Setting: Large U.S. health system from 2012 to 2024. Patients: Adults (age ≥ 18 yr) meeting both Centers for Disease Control and Prevention Adult Sepsis Event and Sepsis-3 clinical criteria for septic shock. Patients with missing hospital discharge disposition and incomplete vasopressor dosage information were excluded. Interventions: None. Measurements and Main Results: Clinical criteria for refractory septic shock were operationalized as concomitant occurrence of norepinephrine (base) equivalent greater than 0.5 µg/kg/min and lactate greater than 2 mmol/L. Risk-adjusted hospital mortality was assessed with a generalized linear mixed-effects model with a random effect for hospital and fixed effects for age, sex, Elixhauser Comorbidity Index, and Sequential Organ Failure Assessment (original description, without cardiovascular component). Of 35,914 patients assessed, 15,732 patients with septic shock were included. Refractory septic shock occurred in 3423 patients (21.8%), with a cumulative incidence of 218 cases (95% CI, 211–224) per 1000 patients with septic shock. Hospital mortality with refractory septic shock was 64.4%, and risk-adjusted hospital mortality odds were 4.87-fold higher (95% CI, 4.46–5.31) compared with patients without refractory septic shock. Conclusions: Clinical criteria for refractory septic shock were fulfilled in about one in five patients with septic shock and associated with substantially higher mortality.

1024 Background: Invasive lobular carcinoma (ILC) is a distinct breast cancer (BC) subtype with dissemination patterns differing from invasive breast carcinoma of no special type (IBC-NST). While genomic differences between ILC and IBC-NST have been described, the extent to which molecular and immune profiles vary by metastatic organ and histology is poorly characterized. Methods: We conducted a retrospective analysis to evaluate organ- and histology-specific molecular features of metastatic BC (mBC). Patients with metastatic IBC-NST or pure ILC underwent NGS (592, NextSeq; WES/WTS, NovaSeq; Caris Life Sciences). Tumor mutational burden (high ≥10 mut/Mb), PD-L1 expression (22C3), and immune cell fractions (RNAseq deconvolution, quanTIseq) were assessed. Analyses were restricted to sites with ≥10 biopsies per histology. Comparisons used chi-square or Mann–Whitney U tests with multiple testing correction (q < 0.05). Results: A total of 2645 mBC biopsies (605 ILC; 2040 IBC-NST) were analyzed (Table). In ILC, ERBB2 mut frequency differed by metastatic site (q<0.01), with higher prevalence in liver (32.7%) and lower in gastrointestinal (GI) lesions (3.7%). In IBC-NST, ESR1 and GATA3 mut and FGFR1 amplification were enriched in liver metastases, whereas PD-L1 expression was highest in skin (20.7%) and lowest in liver (5.0%). No organ-specific differences were observed for PIK3CA, AKT, PTEN, BRCA1/2 or RB1 . Across metastatic sites, both ILC and IBC-NST showed differences in B cells, macrophages (M1/M2), neutrophils, NK cells, dendritic cells, CD8+ T cells, and Tregs (all q < 0.05); CD4+ T-cell differences were observed only in IBC-NST (q = 0.002). In organ-specific ILC vs IBC-NST comparisons, CDH1 mut were more frequent in ILC across sites, along with higher PIK3CA mut in skin (ILC 51.3% vs IBC-NST 34.4%) and higher ERBB2 mut in liver (32.7% vs 3.3%), whereas a higher TP53 mut frequency was observed in IBC-NST in skin (28.5% vs 52.3%) and lymph nodes (LND) (23.5% vs 55.5%) (all q < 0.01). Conclusions: mBC exhibits marked organ-specific molecular and immune heterogeneity that differs by histology. These findings support histology- and site-aware interpretation of metastatic biopsies and may inform biomarker assessment and treatment decisions in advanced disease. BC-NST ILC Skin LND Bone Breast Liver Perit. CNS q-value Skin LND Bone Breast GI Liver GYN Perit. CNS q-value N (specimens) 785 401 109 361 220 15 44 - 172 84 62 56 56 54 43 37 11 - ERBB2 mut (%) 3.2 3.1 3.2 2.3 3.3 7.1 2.5 1.0 7.1 7.4 16.4 15.4 3.7 32.7 2.4 5.7 11.1 <0.01 ESR1 mut (%) 9.4 5.2 8.3 16.0 28.2 7.1 2.4 0.0 7.8 7.2 8.9 9.8 16.7 26.0 4.9 20.0 0.0 0.9 FGFR1 amp (%) 10.1 6.6 5.6 12.8 16.5 0.0 9.7 0.02 4.4 3.4 6.7 6.1 2.4 5.6 7.7 18.5 0.0 1.0 IHC-PD-L1 (%) 20.7 - 5.3 16.0 5.0 11.1 10.3 0.02 8.9 - 5.0 5.7 6.1 0.0 0.0 0.0 14.3 1.0 TMB-High (%) 10.7 10.1 8.8 8.8 8.5 14.3 21.4 0.8 27.6 11.0 19.6 28.0 11.3 19.6 9.8 32.4 22.2 0.8 Perit: peritoneum; CNS: central nervous system; GYN: genital tract.

Abstract We describe early experience with beta-lactam therapeutic drug monitoring (TDM) in a high-volume outpatient parenteral antimicrobial therapy program. In selected patients, TDM informed dose optimization and toxicity mitigation. Illustrative cases highlight feasibility and emerging lessons supporting beta-lactam TDM in outpatient care.

Abstract Rationale Community-acquired pneumonia (CAP) remains a leading cause of morbidity and mortality worldwide; current guidelines recommend either the use of β-lactam therapy with a macrolide (azithromycin; AZM) or monotherapy with a fluoroquinolone for treatment. Limited evidence exists on their comparative effectiveness. To address this gap, we examined the differences in outcomes among CAP patients treated with β-lactam therapy plus AZM or fluoroquinolone monotherapymethods: We emulated a randomized clinical trial that hypothetically assigned patients to β-lactam therapy plus AZM or fluoroquinolone. Eligible patients were all adults hospitalized for nonsevere community-acquired pneumonia (CAP) based on ATS/IDSA criteria; at Mayo Clinic hospitals (3 academic and 16 community) between May 2018 and September 2022 and received one of the two treatments within 12 hours of admission. Ensemble machine learning with augmented inverse probability weighting (AIPW) was used to evaluate “intention to treat” effects on hospital-free days (HFDs), 180-day mortality, use of advanced respiratory support, in-hospital mortality, and the composite of advanced respiratory support and/or in-hospital mortality. We used the E-value and post-discharge systolic blood pressure (SBP) (negative outcome) to evaluate effects of potential unmeasured confounding and alternative “doubly robust” inverse probably weighting with regression adjustment (IPWRA) to evaluate robustness of the findings. Results 2,451 patients (2,142 β-lactam therapy plus AZM and 309 fluoroquinolone) were eligible and included in the analyses: 53.9% were female, 86.8% were White, and mean age was 58.4 years (SD: 17.02). Compared with β-lactam therapy plus AZM, the fluoroquinolone group experienced significantly higher HFD (1.50 days; 95% CI: 1.08, 1.91), lower use of advanced respiratory support (RR: 0.32; 95% CI: 0.09, 0.54), lower in-hospital mortality (RR: 0.14; 95% CI: 0.00, 0.40), and composite of advanced respiratory support and/or in-hospital mortality (RR: 0.29; 95% CI: 0.08, 0.49). Moderate to large e-values (ranging from 3.50 to 4.74) and use of negative outcomes (post-discharge SBP) suggested that unmeasured confounding is unlikely to change the findings. Sensitivity analysis using IPWRA showed very similar results. Conclusion Among hospitalized patients with non-severe CAP, treatment with fluoroquinolone monotherapy was associated with more hospital-free days, lower in-hospital mortality, and reduced need for advanced respiratory support compared with AZM and β-lactam combination. The findings highlight the role of fluoroquinolone as a beneficial alternative CAP patients. However, further studies are needed to explore the underlying mechanisms driving these differences and assess whether specific patient subgroups may benefit most from quinolone-based therapy. This abstract is funded by: none