Identification of Surrogate Outcome Biomarkers in Lung Allograft Recipients With Bronchiolitis Obliterans: Implications for Randomized Controlled Trials
BACKGROUND. We developed a prospective, multicenter “registry” to evaluate the effect of extracorporeal photopheresis for lung transplant recipients who develop chronic lung allograft dysfunction (CLAD) with the bronchiolitis obliterans syndrome (BOS) phenotype (CLAD/BOS) and who are refractory to conventional standard-of-care therapy. METHODS. Data from 258 lung transplant recipients enrolled in the Registry between April 2015 and April 2022 were included in this analysis. All recorded parameters (eg, demographics), including forced expiratory volume in 1 s (FEV1) measurements and indices (FEV1% baseline, FEV1 rate of decline) at several time periods, were included in multivariate linear/logistic and Kaplan-Meier analyses to evaluate potential associations with survival. RESULTS. Mortality at 6 and 12 mo after CLAD/BOS diagnosis was 5% and 14%, whereas mortality at 6 and 12 mo after enrollment was 15% and 26%, respectively. The primary cause of death in the cohort was respiratory failure or graft failure (74%). Rate of FEV1 decline (log) at enrollment was independently associated with survival (log days) from CLAD/BOS diagnosis and enrollment (r = 0.55 and r = 0.3, respectively). The rates of FEV1 decline among survivors were lower (–77 ± 89 mL/mo) compared with nonsurvivors (–148 ± 155 mL/mo) at 6 mo after enrollment (P = 0.0001). CONCLUSIONS. The rate of FEV1 decline quantified using at least 5 FEV1 measurements is a robust surrogate outcome. We plan to use these findings to revise our randomized controlled trial to facilitate risk adjustment using FEV1 rate of decline strata at enrollment and as a scientifically valid surrogate for outcome.
Extended Trochanteric Osteotomy Combined with Medial Reduction Corticotomy to Correct Femoral Deformity at the Time of Revision Total Hip Arthroplasty
Background: An extended trochanteric osteotomy (ETO) is commonly used to improve exposure and facilitate femoral component removal in revision total hip arthroplasty (THA). An additional medial corticotomy may be used in conjunction with an ETO to correct a femoral deformity, particularly varus remodeling in association with a failed femoral component. This study evaluated the outcomes of combining an ETO with a medial corticotomy in revision THA, with emphasis on implant fixation, femoral alignment, bone union, and clinical outcomes. Methods: Of the 612 ETOs performed between 2003 and 2013, 13 patients (9 men and 4 women) underwent ETO combined with a medial corticotomy to correct varus remodeling, representing 2% of all ETOs during that period. The average follow-up was 8 ± 3.5 years. The mean age at surgery was 67 ± 13.5 years. The mean body mass index was 32 ± 7.7 kg/m 2 . Radiographs were reviewed to measure preoperative and postoperative femoral deformity, time to consolidation, and femoral fixation. Clinical outcomes were evaluated using the Harris Hip Score (HHS). Results: All patients had preoperative varus femoral deformity (mean 16.3° ± 5.7°). The mean postoperative alignment was 4.3 ± 1.6° varus achieving an average correction of 12° (95% CI −15.7 to −8.3, p < 0.0001). Both the ETO and the medial corticotomy consolidated in 10 of 11 patients (91%) with available 1-year radiographs at a mean of 11 ± 7.7 months. The mean HHS improved significantly from 42 preoperatively to 82 at 5-year follow-up (p = 0.0002). Complications related to the ETO and corticotomy occurred in 4 patients (30%), including 1 intraoperative fracture, 1 postoperative greater trochanteric fracture, 1 nonunion of the medial corticotomy, and 1 postoperative wound-hematoma. All femoral components remained well fixed at final follow-up. Conclusion: The combination of ETO and medial corticotomy in revision THA effectively corrected femoral alignment in patients with a preoperative varus deformity and was associated with significant functional improvement at the final follow-up. Level of Evidence: Level IV . See Instructions for Authors for a complete description of levels of evidence.
Abstract PR005: Exploiting CTPS1 dependency for the treatment of ovarian cancer
Abstract Despite therapeutic advances, ovarian cancer (OC) recurrence remains common and outcomes for advanced disease are poor, highlighting the need for novel therapeutic targets. To this end, we identified CTPS1 as a highly expressed and essential gene for the survival of many OC cell lines, including models resistant to chemotherapy and PARP inhibitors. CTPS1 is one of two enzymes, alongside CTPS2, responsible for the de novo synthesis of cytidine triphosphate (CTP), a critical nucleotide required for DNA and phospholipid biosynthesis. We discovered that CTPS1 is the predominant isoform expressed in OC cells, with significantly higher levels of expression in advanced and resistant disease compared to normal tissue, benign lesions and treatment naïve cancers. Intriguingly, 25% of all OC samples were found to completely lack CTPS2 protein expression suggesting their near complete reliance on CTPS1 for survival. Using CTPS1 siRNAs and genetically engineered OC cells with a degradation tag (dTAG) fused to the C-terminus of endogenous CTPS1 alleles, we showed that CTPS1 knockdown or proteasomal degradation induces an S-phase cell cycle arrest followed by apoptosis. Leveraging a first-in-class, highly selective, and orally bioavailable CTPS1 inhibitor (STP938) developed by Step Pharma, we identified nanomolar-range IC50 values across a panel of over 20 OC cell lines and validated its anti-neoplastic activity in ex vivo patient-derived xenograft (PDX) models. STP938 synergized with standard-of-care chemotherapy and PARP inhibitors, even in resistant models, further supporting its clinical potential. To elucidate STP938’s mechanism of action, we performed multi-omic profiling (bulk RNAseq, phospho- and total proteomics) on sensitive and isogenic resistant OC lines, as well as single-cell RNAseq of an OC PDX tumor following in vivo treatment with vehicle or STP938, revealed dysregulation of DNA replication, cell cycle, and metabolic pathways. As expected, STP938 rapidly depleted CTP levels, which remain suppressed for 72 hours, suggesting insufficient salvage pathway compensation which ultimately compromised cancer cell viability. As CTP is also a direct precursor for activated intermediates in phospholipid biosynthesis. Mass-spectrometry based lipidomics and metabolomics were employed to interrogate the impact of STP938 in these processes where numerous changes were found. To uncover mechanisms of resistance to STP938 and reveal therapeutic vulnerabilities, we conducted genome-wide CRISPR knockout screens in multiple treatment naïve and STP938 resistant models and analysis of results are ongoing. In collaboration with Step Pharma, a Phase 1a/b clinical trial of STP938 is currently enrolling patients with advanced solid tumors, including an expansion cohort for CTPS2 null OC patients (NCT06297525). These laboratory discoveries and ongoing clinical efforts aim to enable broader uptake of this novel therapeutic approach to improve long-term outcomes in patients with CTPS1-dependent disease. Citation Format: Xiyin Wang, Michael J. Emch, Lauren A. Voll, Rebecca Epp, Esther P. Rodman, Noa Odell, Nicole A. Pearson, Xiaonan Hou, Matthew P. Goetz, Scott H. Kaufmann, S. John Weroha, Philip Beer, John R. Hawse. Exploiting CTPS1 dependency for the treatment of ovarian cancerPR005: Exploiting CTPS1 dependency for the treatment of ovarian cancer [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Ovarian Cancer Research; 2025 Sep 19-21; Denver, CO. Philadelphia (PA): AACR; Cancer Res 2025;85(18_Suppl):Abstract nr PR005.
Development and validation of a gene expression signature to predict early events in patients with follicular lymphoma
Abstract Although follicular lymphoma (FL) typically follows an indolent course, patients with FL who experience early events, such as transformation or progression, have increased risk of death related to lymphoma. The FL24Cx is an algorithm based on a 45-target gene expression profiling (GEP) assay, which was developed and trained using 265 formalin-fixed, paraffin-embedded tissue samples on a reliable platform to predict, at the time of diagnosis, whether a patient will experience an event within 24 months. The modeling also confirmed and relied upon previously reported synergy between immune response (IR) gene expression signatures IR1 and IR2. Once locked, the 5-factor logistic regression FL24Cx model was independently validated in a retrospectively assessed cohort of 232 patients from 2 immunochemotherapy-treated arms of SWOG Cancer Research Network S0016 phase 3 clinical trial, in which it assigned 169 patients to the low-risk group with 29 events before 24 months (17.2%) and 63 patients to the high-risk group with 24 events before 24 months (38.1%). The relative risk of an event within 24 months after registration among patients who were classified into the high-risk group relative to patients who were classified into the low-risk group was 2.2 (95% confidence interval, 1.41 to 3.51). An up-front GEP biomarker, such as the FL24Cx, rigorously validated in a clinical laboratory and with a clinically relevant turnaround time, could identify and steer enrollment of patients at high risk for early events in clinical trials, thus enabling timely interpretation of such trials and increasing the pace of innovation.
Artificial intelligence accelerates the interpretation of measurable residual B lymphoblastic leukemia by flow cytometry
Abstract Measurable residual disease (MRD) assessment by flow cytometry (FC) plays an essential role in prognosis and therapy escalation of B-cell acute lymphoblastic leukemia (B-ALL). However, the high degree of expertise and manual analysis time required limits the availability of this assay. To overcome this limitation, we developed a data-enhancing artificial intelligence (AI) pipeline that accelerates and simplifies MRD analysis. Unaltered FC files from 171 B-ALL MRD-positive and 89 MRD-negative cases were processed through an AI pipeline trained with 31 expert-gated negative controls. Cluster-informed downsampling reduced FC files from 1.2 million to 155 884 cells per case, on average, (87% cellularity reduction), whereas preserving small MRD populations (median, 100% retention for MRD of <1%) and allowing for true percentage MRD estimates using a correction factor. A deep neural network cell classifier automatically identified normal hematopoietic subsets (macro-averaged F1 score of 0.86); and an AI measure of anomaly discriminated B-ALL from benign mononuclear (area under the curve [AUC] of 0.98) or B-lymphoid cells (AUC of 0.94). Manual analysis of AI-enhanced files was completed in only 1.01 minutes per case, on average (standard deviation of ±0.57); with 100% positive agreement with conventional analysis (for MRD of ≥0.01%), 100% negative agreement, and excellent quantitative correlation (R2 = 0.92). Our cloud-based AI-enhancement solution accelerates B-ALL MRD identification without compromising test performance and has the potential of facilitating B-ALL MRD analysis by more clinical laboratories.
Abstract C145: Baseline participant characteristics from PATHFINDER 2, a prospective interventional study of a multi-cancer early detection test in a population setting
Abstract A blood-based multi-cancer early detection (MCED) test has demonstrated feasibility as a screening tool in large-scale clinical trials. The PATHFINDER 2 (PF2) study (NCT05155605) evaluates safety and performance of the MCED test in a diverse intended-use population. To gauge generalizability of study results, we assessed participant (ppt) baseline characteristics vs general US population data from the National Health and Nutrition Examination Survey (NHANES). PF2, a prospective, multicenter, interventional study, enrolled ppts aged ≥50 y from diverse clinical settings in North America. Enrollment targets for sex and race/ethnicity were established from the 2019 American Community Survey (US Census Bureau). Recruitment strategies were implemented to maximize enrollment for groups historically underrepresented in clinical studies. Exclusion criteria included clinical suspicion of cancer or cancer diagnosis/treatment within 3 y. Data on baseline characteristics and key cancer risk factors were collected at enrollment. We compared the PF2 study population to a nationally representative sample of US adults aged ≥50 y from 2017-2020 NHANES data. NHANES data were weighted using complex, multistage probability sampling to generate a nationally representative sample. There were 35,878 ppts enrolled in PF2; 35,307 clinically eligible and evaluable ppts were included in this analysis. Mean age was 64 y for both PF2 and NHANES; 56.2% were females in PF2 vs 53.6% (95% CI 52.0-55.3%) in NHANES. Race/ethnicity distribution for PF2 vs NHANES was 7.4 vs 11.0% (8.9-13.1%) Hispanic, 74.6 vs 69.7% (65.0-74.5%) non-Hispanic (NH) White, 8.6 vs 10.3% (7.6-13.1%) NH Black, and 5.8 vs 5.1% (3.5-6.8%) NH Asian. In terms of lifestyle characteristics for PF2 vs NHANES, 58.9 vs 29.2% (25.8-32.7%) had at least a bachelor’s degree, 74.8 vs 63.8% (60.6-67.0%) were married/living with a partner, 69.3 vs 53.8% (50.9-56.7%) had never smoked, 66.5 vs 70.4% (68.0-72.8%) were overweight/obese, and 24.2 vs 28.4% (26.4-30.3%) reported never using alcohol. PF2 enrolled a diverse ppt population that is reasonably reflective of the demographics of the US population aged ≥50 y. As is typical for clinical trials, a higher percentage of PF2 vs NHANES ppts reported lifestyle characteristics associated with better health. As the study population largely reflects the MCED test intended-use population, safety and performance results from PF2 are expected to reflect real-world clinical experience. Citation Format: Shirish Gadgeel, Nima Nabavizadeh, Dax Kurbegov, Charles McDonnell, III, James W. Lillard, Jr., Marc Matrana, Alan Roth, Andrea Johnston, Sami Tahhan, Rami Owera, Matthew Margolis, Anuraag Kansal, Margarita Lopatin, Margaret McCusker, Karthik V. Giridhar. Baseline participant characteristics from PATHFINDER 2, a prospective interventional study of a multi-cancer early detection test in a population setting [abstract]. In: Proceedings of the 18th AACR Conference on the Science of Cancer Health Disparities; 2025 Sep 18-21; Baltimore, MD. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2025;34(9 Suppl):Abstract nr C145.
Staging Alzheimer’s disease through amyloid and tau PET
Abstract A workgroup assembled by the Alzheimer’s Association recently described a conceptual framework for Alzheimer’s disease biological staging based on amyloid and tau PET imaging. However, specific tau PET cut points were left to be determined, a step necessary prior to clinical application. We sought to operationalize and evaluate Alzheimer’s disease biological staging by identifying meaningful tau PET cut points to define the four biological stages in a well-characterized participant cohort and describe the features of individuals placed into the different biological stages. The primary analysis included 896 participants in the Mayo Clinic Study of Aging or the Mayo Clinic Alzheimer’s Disease Research Center longitudinal cohorts. A validation cohort consisted of 328 participants in the Alzheimer’s Disease Neuroimaging Initiative. Both cognitively normal and impaired individuals with positive amyloid PET and evaluable tau PET imaging were included. Tau PET cut points were identified with Gaussian mixture models to characterize Alzheimer’s disease biological stage in study participants with different clinical diagnoses and objective degrees of cognitive impairment as measured by Mini-Mental State Examination. A tau PET cut point in the medial temporal region and two cut points in the temporoparietal region were identified to produce, collectively, the four Alzheimer’s disease biological stages described in the revised criteria. Increasing stage was associated with greater likelihood of mild cognitive impairment and dementia diagnosis and worsening cognitive performance on Mini-Mental State Examination and Clinical Dementia Rating Sum of Boxes, a result that was reproduced in the independent Alzheimer’s Disease Neuroimaging Initiative cohort. This study provided empirical validation for the concept of using amyloid PET and tau PET to separate subjects with biomarker-proven Alzheimer’s disease into four biological stages with distinct characteristics.
Stratifying lung adenocarcinoma risk with multi-ancestry polygenic risk scores in East Asian never-smokers
Abstract Background Lung adenocarcinoma in never-smokers is a major public health burden, especially among East Asian women. Polygenic risk scores (PRSs) are promising for risk stratification but are primarily developed in European-ancestry populations. We aimed to develop and validate single- and multi-ancestry PRSs for East Asian never-smokers to improve lung adenocarcinoma risk prediction. Methods PRSs were developed using genome-wide association study summary statistics from East Asian (8002 cases; 20 782 controls) and European (2058 cases; 5575 controls) populations. Single-ancestry models included a PRS with 25 single nucleotide variants (PRS-25), PRS clumping and thresholding (CT), and LDpred2; multi-ancestry models included LDpred2 plus European PRS-128, PRS-CSx, and clumping and thresholding, super learning, empirical Bayes (CT-SLEB). Performance was evaluated in independent East Asian data from the Female Lung Cancer Consortium and externally validated in the Nanjing Lung Cancer Cohort. We assessed predictive accuracy via area under the curve operating procedure (AUC), with 10-year and (ages 30-80 years) absolute risks estimates. Results The best multi-ancestry PRS, using East Asian and European data via CT-SLEB, outperformed the best East Asian-only (LDpred2; AUC = 0.629, 95% confidence interval [CI] = 0.618 to 0.641), achieving an AUC of 0.640 (95% CI = 0.629 to 0.653) and odds ratio of 1.71 (95% CI = 1.61 to 1.82) per standard deviation increase. Nanjing Lung Cancer Cohort validation confirmed robust performance (AUC = 0.649, 95% CI = 0.623 to 0.676). The top 20% PRS group had a 3.92-fold higher lung adenocarcinoma risk than the bottom 20%. Further, the top 5% PRS group reached a 6.69% lifetime absolute risk. Notably, this group reached the average population 10-year lung adenocarcinoma risk at age 50 years (0.42%) by age 41 years, 9 years earlier. Conclusions Multi-ancestry PRS approaches enhance lung adenocarcinoma risk stratification in East Asian never-smokers, with consistent external validation, suggesting future clinical utility.
Everolimus and Low-Dose Tacrolimus After Heart Transplant in Children
ImportanceStudies suggest that everolimus may reduce the risk of rejection, cardiac allograft vasculopathy (CAV), chronic kidney disease (CKD), and cytomegalovirus (CMV) after heart transplant. Everolimus use is controversial because of data demonstrating higher infection deaths when everolimus is introduced de novo after transplant. It is unclear whether everolimus is safe and effective when initiated at 6 months posttransplant in children, a population in which median graft survival is limited to 15 years and randomized clinical trials are lacking.ObjectiveTo evaluate the safety and efficacy of everolimus combined with low-dose tacrolimus to prevent major adverse transplant events (MATEs) in children after heart transplant.Design, Setting, and ParticipantsMulticenter, randomized, open-label, clinical trial enrolling 211 patients who were alive 6 months after pediatric heart transplant at 25 US sites from February 2018 to August 2020. The last date of follow-up was April 17, 2023.InterventionsParticipants were randomized to receive everolimus and low-dose tacrolimus (n = 107) or standard-dose tacrolimus and mycophenolate mofetil (n = 104) for 30 months.Main Outcomes and MeasuresThe primary efficacy end point was the MATE-3 score at 30 months, a validated composite ordinal end point including acute cellular rejection, CAV, and CKD. The primary safety end point was the MATE-6 score, encompassing the MATE-3 score plus antibody-mediated rejection, infection, and posttransplant lymphoproliferative disorder.ResultsAmong 211 children randomized, the mean age was 8.2 (SD, 6.3) years, 97 (46%) underwent transplant for congenital heart disease, and 49 (23%) were treated for rejection before 6 months. At 30 months, the mean MATE-3 score did not differ between the 2 treatment groups (mean difference, −0.32; 95% CI, −0.90 to 0.20; P = .16). The mean MATE-6 score was no higher in the everolimus group than in the mycophenolate group (baseline-adjusted mean difference, −0.40; 95% CI, −1.81 to 0.93), meeting the success criterion for safety (noninferiority margin &lt;3). There were no differences in graft survival, MATE-free survival, or freedom from any individual MATE. Everolimus was associated with greater improvement in estimated glomerular filtration rate at 12 months (mean difference, 10.5 mL/min/1.73 m2; 95% CI, 1.09-19.91 mL/min/1.73 m2) and a lower incidence of CMV infection (hazard ratio, 0.50; 95% CI, 0.26-0.93).Conclusions and RelevanceAmong 6-month pediatric heart transplant survivors, everolimus and low-dose tacrolimus did not differ from tacrolimus and mycophenolate in preventing the composite of cellular rejection, CAV, and CKD at 30 months. However, everolimus and low-dose tacrolimus appear to be safe based on the total burden of 6 MATEs and may be associated with improved kidney function and less CMV infection.Trial RegistrationClinicalTrials.gov Identifier: NCT03386539
Stereotactic Radiosurgery Versus Observation in Small- and Medium-Sized Vestibular Schwannoma Patients With Normal Hearing: A Retrospective International Multicenter Study
BACKGROUND AND OBJECTIVES: The therapeutic approach for small- and medium-sized vestibular schwannoma (VS) with normal hearing function remains controversial, with limited comparative data regarding hearing outcomes after stereotactic radiosurgery (SRS) or observation (OBS). We evaluated the serviceable hearing preservation, loss of American Academy of Otolaryngology-Head and Neck Surgery class A hearing, and tumor control (TC) across individuals with Koos grade I and II VSs and normal hearing at presentation who underwent SRS or OBS. METHODS: In this multicenter international study, we retrospectively analyzed the hearing, radiological, and neurological outcomes of patients who underwent SRS (SRS group) or OBS (OBS group). The cohorts were matched using propensity scores based on age, sex, tumor volume, pure-tone average, and speech discrimination score at a 1:1 ratio without replacement. RESULTS: After matching, each group comprised 57 patients. The median follow-up was 49 and 37 months for the SRS and the OBS groups, respectively ( P = .3). The 5- and 9-year serviceable hearing preservation rates in the SRS group were 76.2% and 42.4% vs 56.1% and 16.8% in the OBS group ( P = .17). Class A preservation occurred in 57.9% (33/57) of the SRS and 52.6% (30/57) of the OBS cohorts ( P = .70). Regarding the TC rates, SRS was associated with significantly higher TC rates ( P < .0001). CONCLUSION: We found that SRS is significantly superior regarding TC and provided noninferior hearing outcomes compared with OBS in VS patients with American Academy of Otolaryngology-Head and Neck Surgery class A hearing at presentation. Therefore, we suggest performing SRS in individuals with VS and normal hearing function.