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1936 citation(s) found for "Jacob, J".

Perioperative pembrolizumab in early-stage non-small cell lung cancer (NSCLC): safety, efficacy, and exploratory biomarker analysis
Wood, Cameron , Lyniv, Liliana, Isaacs, James M, Kaufman, Jacob M., Oduah, Eziafa , Clarke, Jeff, Crawford, Jeffrey, Stinchcombe, Thomas E. , Tong, Betty , Wigle, Dennis A. , Dragnev, Konstantin H. , Antonia, Scott , Ready, Neal , Wigle, Dennis, Ready, Neal , Wood, Cameron , Isaacs, James , Wang, Xiaofei , Gu, Lin, Weinhold, Kent J.

Journal for ImmunoTherapy of Cancer | February 4, 2025 | Volume: 13 | Issue: 2 | Pages: e010395

10.1136/jitc-2024-010395 | PMID 39904561 Get It

Background Our study was designed to determine the safety, efficacy, and immunological effects of perioperative pembrolizumab in early-stage NSCLC. Methods This is a single-arm phase II study of perioperative pembrolizumab in patients with untreated, clinical stage IB to IIIA NSCLC. Patients received two doses of 200 mg pembrolizumab, surgery, standard adjuvant chemotherapy, followed by four doses adjuvant pembrolizumab. The primary objective of this study was to determine surgical feasibility rate, and secondary objectives are pathological response rate, treatment adverse events, efficacy data, and exploratory analysis of biomarkers. Results 30 patients initiated perioperative pembrolizumab, and 25 completed tumor resection. At median follow-up of 59 months after surgical resection, seven patients had disease progression, while six had died representing. A 5-year progression-free survival (PFS) from time of surgery was 72.0% (56.4%–91.9%) and overall survival (OS) from time of surgery was 75.8% (60.7%–94.7%). Major pathological response (MPR) was found in seven tumors (28%) including two complete responses (4%). Across all treated patients, four receiving neoadjuvant and four receiving adjuvant pembrolizumab experienced treatment-related adverse events of grade 3 or higher with no grade 5 events. Plasma proprotein convertase subtilisin/kexin type 9 (PCSK9) levels increased across our patient cohort over time from baseline until postsurgery and remained elevated at the end of treatment. There was a significant difference between mean plasma PCSK9 levels for patients with MPR versus all other patients on study when checked postoperatively. Conclusions Perioperative pembrolizumab was safe and effective with promising MPR rate, PFS, and OS.
Shear wave elastography of the deltoid muscle in healthy volunteers – quantifying age-dependent normal values
Ivanov, David , Voelkel, Jacob E., Giambini, Hugo , Sánchez‐Sotelo, Joaquín , Dave, Jaydev K. , Kummer, Tobias , Sanchez-Sotelo, J.

Shoulder & Elbow | February 3, 2025 | Volume: 18 | Issue: 2 | Pages: 257-265

10.1177/17585732251315952 | PMID 39906875 Get It

Introduction Reverse shoulder arthroplasty (RSA) is performed for various shoulder pathologies. Inadequate tensioning of the deltoid muscle can lead to complications, highlighting the need for optimization. Preoperative quantification of deltoid health may improve operative execution and outcomes. Shear wave elastography (SWE) quantifies stiffness as a marker for muscle health and tensioning. This study establishes normal reference values for the deltoid in healthy individuals. Methods 40 participants were enrolled, 10 in each 18–30, 31–40, 41–55, and 55 + age groups. Two operators performed SWE in 3 deltoid regions, and the intra- and inter-operator agreement was assessed. Results Mean values were 23.2 ± 4.6, 26.4 ± 5.6, and 17.9 ± 5.2 kPa for the anterior, lateral, and posterior regions. The posterior region did not show any age dependency. However, there were significant differences between the age groups of 18–30 and 55 + years in the anterior (19.7 ± 3.7 vs. 26.7 ± 5.3 kPa) and lateral (22.0 ± 5.4 vs. 30.2 ± 8.8 kPa). Intra-operator reliability ranged from 0.45 to 0.60, and inter-reader agreement from 0.57 to 0.85. Conclusion This study provides reference values of deltoid stiffness which could serve as a comparison with clinical measurements for RSA operative planning and execution and prediction of surgical outcomes.
694: BLOOD PRESSURE VARIABILITY IN PATIENT RECEIVING BOLUS VERSUS CONTINUOUS INFUSION ANTIHYPERTENSIVES
Wieruszewski, Erin D. , Brown, Caitlin S. , Mattson, Alicia E , Jackson, Gia, Klinger, Jacob A., Cole, Kristin C., Rabinstein, Alejandro, Klinger, Jacob A., Cole, Kristin C., Bellolio, Fernanda , Cabrera, Daniel , Rabinstein, Alejandro A.

Critical Care Medicine | January 31, 2025 | Volume: 53 | Issue: 1 | Pages: No page available

10.1097/01.ccm.0001101440.73637.5d Get It

975: LEVOFLOXACIN DRUG MONITORING IN CONTINUOUS VENOVENOUS HEMODIAFILTRATION FOR LEGIONELLA PNEUMONIA
Whitenack, Kaylee, Robinson, John A. , Schwarz, Jacob B. , Robinson, John, Ilges, Dan , Schwarz, Jacob

Critical Care Medicine | January 31, 2025 | Volume: 53 | Issue: 1 | Pages: No page available

10.1097/01.ccm.0001102564.45586.c3 Get It

P-861. CTX-M-15-producing H30 ST131 Escherichia coli contributes to carbapenem use for E. coli bloodstream infections in the United States
Mackow, Natalie , Shao, Wanying, Ge, Lizhao , Komarow, Lauren , Boutzoukas, Angelique E , Herc, Erica , Arias, César A. , Satlin, Michael J. , Dhar, Sorabh , Shelburne, Samuel A. , Hill, Carol , Greenwood‐Quaintance, Kerryl E. , Schmidt-Malan, Suzannah M., Fowler, Vance G. , Kreiswirth, Barry N. , Jiang, Jianping , Chen, Liang , Doi, Yohei , Arias, César A. , Albin, Owen , Saade, Elie , Miller, Loren G , Jacob, Jesse T. , Kršák, Martin , Huskins, W. Charles , Patel, Robin , Fowler, Vance G. , Tamma, Pranita D. , Kreiswirth, Barry N , van Duin, David

Open Forum Infectious Diseases | January 29, 2025 | Volume: 12 | Issue: Supplement_1 | Pages: No page available

10.1093/ofid/ofae631.1053 Get It

Abstract Background Drug-resistant E. coli is a leading cause of antimicrobial resistance-associated deaths globally. Specifically, resistance to ceftriaxone (CRO-R) is increasing in E. coli. High-risk clonal group ST131 and its pandemic H30 subclone are of high concern yet studies characterizing these infections are limited. We evaluated baseline characteristics and clinical outcomes associated with H30 ST131, non-H30 ST131 and non-ST131 E. coli bloodstream infections (BSI). Methods Patients with monomicrobial carbapenem-susceptible E. coli BSI that were matched 1:1 by study site (CRO-R and CRO-susceptible community-acquired and hospital onset cases) were prospectively enrolled from 14 United States hospitals between November 12, 2020 to April 28, 2021 in the multicenter Study of Highly Resistant E. coli (SHREC). Isolates underwent whole genome sequencing. The primary outcome was a 30-day Desirability of Outcome Ranking (DOOR) after index culture including clinical response to treatment and all-cause mortality. Results There were 92 (33%) H30 ST131, 29 (10%) non-H30 ST131, and 161 (57%) non-ST131 isolates in 282 E. coli BSI (Table 1). Most ceftriaxone resistance was conferred by CTX-M-15 produced by H30 ST131 isolates (Figure 1, Table 1). H30 ST131 BSI patients were older (median age [IQR] 70.5 [63,76] vs. 67 [56,77] vs 65 [51,74] years, p = 0.017), had higher Charlson comorbidity indices (3 [2,5] vs. 2 [1,4] vs. 2 [1,4], p=0.009), and were more often admitted from long-term care facilities (18/92 [20%] vs. 3/29 [10%] vs. 7/161 [4%], p = 0.003) compared to non-H30 ST131 and non-ST131 BSI patients. Among H30 ST131 isolates, high rates of antibiotic resistance were observed to cephalosporins and fluoroquinolones, resulting in significantly more carbapenem use compared with non-H30 ST131 and non-ST131 isolates (75/92 [82%] vs. 14/29 [48%] vs. 50/161 [31%], p < 0.001) (Figure 2). 30-day DOOR and hospital length of stay did not differ between groups (Table 2). Conclusion Compared with non-H30 ST131 and non-ST131 E. coli BSI, H30 ST131 E. coli BSI have a unique epidemiology with more healthcare exposures, comorbidities and antibiotic resistance and are more likely to be treated with carbapenems, though no significant difference in clinical outcomes was observed. Disclosures Yohei Doi, MD, PHD, AbbVie: Honoraria|Entasis: Grant/Research Support|Gilead: Advisor/Consultant|GSK: Advisor/Consultant|Meiji Seika: Advisor/Consultant|Moderna: Advisor/Consultant|Pfizer: Advisor/Consultant|Shionogi: Advisor/Consultant|Shionogi: Honoraria Elie Saade, MD, MPH, FIDSA, Janssen Global Services: Advisor/Consultant|Janssen Global Services: Advisor/Consultant|Janssen Research and Development: Advisor/Consultant|Janssen Research and Development: Advisor/Consultant Loren G. Miller, MD MPH, Armata: Grant/Research Support|Contrafect: Grant/Research Support|GSK: Grant/Research Support|Merck: Grant/Research Support|Paratek: Grant/Research Support Michael J. Satlin, MD, AbbVie: DSMB participant|bioMerieux: Grant/Research Support|Merck: Grant/Research Support|Selux Diagnostics: Grant/Research Support|SNIPRBiome: Grant/Research Support W. Charles Huskins, MD, MSc, ADMA Biologics: Advisor/Consultant|Bristol Myers Squibb: Stocks/Bonds (Public Company)|Pfizer: Advisor/Consultant|Pfizer: Stocks/Bonds (Public Company)|Zimmer Biomet: Stocks/Bonds (Public Company) Carol Hill, PhD, Glaxo SmithKline: Retirement Health, Cash Balance Plan|Glaxo SmithKline: Stocks/Bonds (Public Company) Robin Patel, MD, a patent on Bordetella pertussis/parapertussis PCR issued, a patent on a device/method for sonication with royalties paid by Samsung to Mayo Clinic, a: See above|MicuRx Pharmaceuticals and BIOFIRE: Grant/Research Support|PhAST, Day Zero Diagnostics, Abbott Laboratories, Sysmex, DEEPULL DIAGNOSTICS, S.L., Netflix, Oxford Nanopore Technologies and CARB-X: Advisor/Consultant|Up-to-Date and the Infectious Diseases Board Review Course.: Honoraria Vance G. Fowler, MD, MHS, Affinergy: Advisor/Consultant|ArcBio: Stocks/Bonds (Private Company)|Armata: Advisor/Consultant|Astra Zeneca: Advisor/Consultant|Astra Zeneca: Grant/Research Support|Basilea: Advisor/Consultant|Basilea: Grant/Research Support|ContraFect: Advisor/Consultant|ContraFect: Grant/Research Support|Debiopharm: Advisor/Consultant|Destiny: Advisor/Consultant|EDE: Grant/Research Support|Genentech: Advisor/Consultant|Genentech: Grant/Research Support|GSK: Advisor/Consultant|Janssen: Advisor/Consultant|Karius: Grant/Research Support|MedImmune: Grant/Research Support|Merck: Grant/Research Support|sepsis diagnostics: Patent pending|UptoDate: Royalties|Valanbuio: Stocks/Bonds (Private Company)|Valanbuio: Stocks/Bonds (Private Company) David van Duin, MD, PhD, Merck: Advisor/Consultant|Merck: Grant/Research Support|Pfizer: Advisor/Consultant|Qpex: Advisor/Consultant|Roche: Advisor/Consultant|Shionogi: Advisor/Consultant|Shionogi: Grant/Research Support
Platelet Concentration Explains Variability in Outcomes of Platelet-Rich Plasma for Lateral Epicondylitis: A High Dose Is Critical for a Positive Response: A Systematic Review and Meta-analysis With Meta-regression
Oeding, Jacob F. , Varady, Nathan H. , Messer, Caden J., Williams, Riley J. , Rodeo, Scott A. , Williams, Riley J , Rodeo, Scott A , Oeding, Jacob F , Dines, Joshua S.

The American Journal of Sports Medicine | January 29, 2025 | Volume: 53 | Issue: 10 | Pages: 2489-2496

10.1177/03635465241303716 | PMID 39868742 Get It

Background: Randomized controlled trials (RCTs) evaluating the efficacy of platelet-rich plasma (PRP) for the management of lateral epicondylitis (LE) have been characterized by substantial variability in reported outcomes. The source of this heterogeneity is uncertain. Purpose: To determine the effect of estimated platelet concentration on the efficacy of PRP for the management of LE. Study Design: Systematic review and meta-analysis; Level of evidence, 2. Methods: All RCTs evaluating the efficacy of PRP in managing LE were identified. RCTs were classified according to whether the study documented a platelet concentration factor of PRP representing a greater than 3-fold increase over whole blood or a supraphysiological platelet dose (high-dose vs low-dose PRP). The primary outcome was the mean difference (MD) in the visual analog scale (VAS) score at latest follow-up. Random-effects and mixed-effects meta-analyses were performed, and meta-regression was used to evaluate whether differences in outcomes after treatment with PRP could be explained by differences in the concentration of PRP used. Results: Overall, 13 RCTs with a total of 791 patients were included in this analysis, with 5 that utilized low-dose PRP and 8 that used high-dose PRP. Meta-analysis of VAS scores reported by studies that used high-dose PRP resulted in an MD of −1.31 (95% CI, −1.87 to −0.75) in favor of PRP over all alternative treatment strategies ( P < .001). Meta-analysis of VAS scores reported by studies that used low-dose PRP resulted in an MD of 0.08 (95% CI, −0.51 to 0.68), suggesting no difference in the effect between PRP and all alternative treatment strategies ( P = .79). The platelet concentration factor of PRP used in each RCT was found to be strongly predictive of the VAS score at final follow-up in meta-regression ( P < .001), with 58.5% of the heterogeneity in the outcomes of PRP between studies explained by the platelet concentration factor alone. Conclusion: The platelet concentration of PRP may play a significant role in the outcomes of patients with LE. A direct linear relationship was observed between the platelet concentration factor of PRP used and the magnitude of patient-reported symptom relief after the management of LE with PRP. Clinicians should ensure a supraphysiological platelet concentration when preparing PRP for the management of LE.
Real-world (RW) treatment patterns and clinical outcomes of patients treated with sequential regorafenib and trifluridine/tipiracil ± bevacizumab (BEV) for metastatic colorectal cancer (mCRC) in the United States (US) community oncology setting: The SEQRT2
Cosgrove, David , Sruti, Ila, Shi, Junxin, Patton, Gregory Alan, Appukkuttan, Sreevalsa , Hocum, Brian , Katta, Arvind, Earl, Jacob, Babajanyan, Svetlana , Bekaii‐Saab, Tanios , Dai, Wei, Earl, Jacob, Barzi, Afsaneh

Journal of Clinical Oncology | January 27, 2025 | Volume: 43 | Issue: 4_suppl | Pages: 62-62

10.1200/jco.2025.43.4_suppl.62 Get It

62 Background: Both Regorafenib (R) and Trifluridine/Tipiracil (T) ± BEV are widely used treatments for mCRC in later lines. This RW study evaluated optimal sequencing and associated outcomes among patients who initiated R and T in sequential lines of therapy (LOT) between LOT1-LOT6 within community oncology settings in the US. Methods: A retrospective study utilizing electronic medical record data from The US Oncology Network examined adult patients with mCRC who initiated R and T ± BEV sequentially between 09/01/2015 and 11/30/2022 (index date), with follow-up until 05/31/2023. Treatment patterns, overall survival (OS) and time to next treatment (TTNT) after sequence were assessed overall, R first (R-T) and T first (T-R). Multivariable Cox regression adjusting for age, sex, ECOG, tumor stage, and prior medication, assessed the association of factors with OS and TTNT. Results: In total, 308 mCRC patients initiating R and T (R-T, 156 pts [140 R-T and 16 R-T+BEV]; T-R, 152 pts [136 T-R and 16 T+BEV-R]) met study criteria. Baseline demographic (mean age 63 yrs, males 55%) and clinical characteristics (70% colon cancer, 58% ECOG 0-1) were similar between the cohorts. Most patients initiated index therapies at the third line of therapy (LOT3) (49% R-T, 45% T-R). The median (IQR) sequence duration was 7.4 (5.6), 6.7 (4.4), and 7.0 (4.7) months, respectively in patients with R-T, T-R, and overall. The median (95% CI) OS was 12.8 (11.2, 14.1) months among R-T and 10.2 (8.8, 11.9) months among T-R patients. Compared to R-T, the adjusted HR for the T-R sequence was 1.2 (95% CI 0.9–1.6; p=0.2). The median (95% CI) TTNT was 9.3 (8.4, 10.3) and 8.6 (7.8, 9.4) months, for R-T and T-R, respectively; the adjusted HR was 1.1 (95% CI 0.8–1.4; p=0.62). Conclusions: Patients initiating R first appeared to have a longer duration of treatment and survival, although not statistically significant. The one-year median duration of survival in this real-world setting confirms the importance of access to these treatments in patients with mCRC and can inform physicians regarding the choice of medications while sequencing therapies in mCRC. Clinical outcomes among R-T and T-R mCRC patients. Variable Level R-T (± BEV)[N 1 = 156] T (± BEV) -R[N 1 = 152] Adjusted 3,4 HR 5 (95% CI)[R-T Reference] Effect OverallSurvival Months – median (95% CI) 12.8(11.2, 14.1) 10.2(8.8, 11.9) 1.20 (0.91, 1.58) 0.20 TTNT 2 Months – median (95% CI) 9.3(8.4, 10.3) 8.6(7.8, 9.4) 1.07 (0.83, 1.37) 0.62 1 Entire R-T and T-R cohorts are presented since 16 patients in each cohort initiated T+BEV. 2 Time To Next Treatment. 3 Overall Survival adjusting for age, gender, stage at diagnosis, ECOG, prior anti-VEGF treatment. 4 Time To Next Treatment adjusting for age, gender, stage at diagnosis, and line of therapy. 5 Hazard Ratio.
Evaluation and comparison of infusion reactions related to prophylactic medication timing for taxane administration
Noble, Jacob , Irvine, Clay, Tevaarwerk, AJ, Cole, Kristin , Gander, Kathleen, Soefje, Scott A. , Mara, Kristin C. , Irvine, Clayton , Tevaarwerk, Amy, Soefje, Scott A , Noble, Jacob M. , Mara, Kristin C , Shah, Vishal

Journal of Oncology Pharmacy Practice | January 21, 2025 | Volume: 32 | Issue: 5 | Pages: 787-791

10.1177/10781552241313058 | PMID 39835368 Get It

Introduction Taxane medications, paclitaxel, and docetaxel, are chemotherapy agents that have a higher incidence of reported hypersensitivity and infusion reactions. To help classify these reactions, the National Cancer Institute Common Terminology Criteria for Adverse Events (NCI CTCAE) is utilized. Prophylactic medications have been used to decrease the incidence and severity of these events. At our institution, medications that patients can receive prior to the initiation of a taxane infusion are a histamine 1 receptor antagonist (H1RA), histamine 2 receptor antagonist (H2RA), a steroid or a combination of these medications. The purpose of this retrospective review was to compare the rates and severity of infusion reactions based on the timing of prophylactic medication administration in the first and second doses of taxane infusions. Methods Patients who received paclitaxel or docetaxel from January 30 th , 2022, through January 30 th , 2023, were included in the analysis. To assist in the identification of a reaction, taxane administrations were flagged for review if a rescue medication was administered after the start of a paclitaxel or docetaxel infusion. The rates and severity of infusion reactions were analyzed based on the timing of prophylactic medication administration. A sub-group analysis comparing infusion reaction characteristics between taxanes given, was performed. Results Of the 1486 taxane infusions that were completed within the year, 249 infusion reactions were confirmed and graded utilizing the NCI CTCAE. When examining the first and second doses of a taxane (N = 536), we identified 222 infusions reactions. The odds of a patient having an infusion reaction, during the first and second doses, was found to be less likely for patients given a prophylactic medication 30 min prior to receiving a taxane compared to those who did not receive a pre-medication (p = 0.037). Conclusion This multisite retrospective study showed that administration of prophylactic medications 30 to 80 min prior to the first and second infusion of a taxane was the optimal timing to decrease the likelihood of patients having an infusion reaction. No difference in the severity of the reaction was seen. Most patients were able to complete the entire infusion, regardless of what rescue medications were used following the infusion reaction.
PD-1 prelimits both the cytotoxic and exhaustion potential in thymic CD8+ T cells and impacts the maintenance of peripheral tumor immunity
Mao, Zhiming , Hirdler, Jacob B. , Gicobi, Joanina K. , Maynes, Mark , Hsu, Michelle A. , Teske, Jacob J. , Li, Ying , Zhao, Geoffrey, Lucien-Matteoni, Fabrice, Silva, Henrique Borges da , Billadeau, Daniel D. , da Silva, Henrique Borges, Borges da Silva, Henrique , Teske, Jacob J , Maynes, Mark A , Dellacecca, Emilia R. , Zhang, Wenjing , Zhao, Geoffrey, Dong, Haidong

No container title available | January 18, 2025 | Volume: No volume available | Issue: No issue available | Pages: No page available

10.1101/2025.01.18.631253 | PMID 39868106 Get It

Abstract Durable T cell immunity against cancer depends on the continual replenishment of effector CD8+ T cells. Thymic output has been correlated with favorable prognosis in cancer patients across a range of ages, suggesting that the thymus is an important source for replenishing T cells capable of controlling cancer progression. However, the effector potential of thymic mature CD8+ T cells and their regulation have not been clearly defined. In this study, we identified the ability of thymic single positive CD8+ T cells to gain effector potential after thymic selection, but they are subject to the regulation of PD-1. We found a previously undisclosed role of PD-1 in limiting both the cytotoxic and exhaustion potential of thymic and peripheral CD8+ T cells. Our results show that although PD-1 inhibition facilitates the expansion of effector CD8+ T cells, effector CD8+ cells gradually lose their antitumor activity within tumor tissues due to advanced exhaustion in the absence of PD-1. Thus, although the preset effector potential in thymic mature CD8+ T cells allows them to rapidly respond to malignant cells in the periphery, PD-1, as a checkpoint, is embedded in the thymic mature CD8+ T cells after positive selection to balance their effector function from exaggeration and exhaustion. Therefore, we propose that a strategy capable of upholding the cytotoxic capacity and avoiding exhaustion of CD8+ T cells during the early stages of PD-1 inhibition therapy is needed to achieve durable antitumor immunity.
PSMA+ Extracellular Vesicles Are a Biomarker for SABR in Oligorecurrent Prostate Cancer: Analysis from the STOMP-like and ORIOLE Trial Cohorts
Andrews, Jack R. , Kim, Yohan , Horjeti, Edlira , Arafa, Ali , Bruycker, Aurélie De , Phillips, Ryan , Song, Daniel Y. , Sartor, Oliver , Orme, Jacob J. , Chaudhuri, Aadel A. , Kiess, Ana P. , Sutera, Philip , Mercier, Carole , Arafa, Ali T. , Gunn, Heather , De Bruycker, Aurélie , Phillips, Ryan , Song, Daniel , Childs, Daniel S , Sartor, A Oliver , Orme, Jacob J , Chaudhuri, Aadel A , Tran, Phuoc T , Kiess, Ana , Sutera, Philip , Mercier, Carole , Ost, Piet , Park, Sean S , Lucien, Fabrice , Gunn, Heather , Childs, Daniel S. , Park, Sean S. , Lucien, Fabrice

Clinical Cancer Research | January 16, 2025 | Volume: 31 | Issue: 6 | Pages: 1142-1149

10.1158/1078-0432.ccr-24-3027 | PMID 39820657 Get It

Abstract Purpose: Two randomized clinical trials (STOMP and ORIOLE) demonstrated that stereotactic ablative radiotherapy (SABR) can prolong androgen-deprivation therapy–free survival or progression-free survival (PFS) in patients with metachronous oligometastatic castration-sensitive prostate cancer (omCSPC). Although most patients with omCSPC have a more modest delay in progression, a small subset achieves a durable response following SABR. We investigated the prognostic and predictive value of circulating prostate-specific membrane antigen-positive (PSMA+) extracellular vesicles (EV) and PSA in a biomarker correlative study using blood samples from three independent patient cohorts. Experimental Design: Plasma samples from 46 patients with omCSPC on the ORIOLE trial and 127 patients with omCSPC on the STOMP trial protocol treated with SABR were included in the study. Pre-SABR PSMA+EV levels (EV/mL) were measured by nanoscale flow cytometry. Kaplan–Meier curves and logistic regression models were used to determine the association of PSMA+EV and PSA levels with clinical outcomes. Results: In the pooled cohorts, the median biochemical PFS were 26.1 and 15.0 months (P = 0.005), and the median radiographic PFS were 36.0 and 25.0 months (P = 0.003) for PSMA+EV-low and -high groups, respectively. The combination of pre-SABR low levels of both PSMA+EV and PSA was associated with a lower risk of radiographic progression (HR, 0.34, 95% confidence interval, 0.18–0.58; P = 0.0002). In the ORIOLE cohort, which included both an SABR arm and an observation arm, low PSMA+EV was predictive of benefit from SABR (P = 0.012). Conclusions: PSMA+EV is a novel prognostic and predictive biomarker of radiographically occult tumor burden in omCSPC. PSMA+EV may inform clinical decisions about identifying patients who will achieve a durable benefit from consolidative SABR alone.