Stadler, Walter M.

Background Immune checkpoint inhibitor-based combinations represent the standard of care for advanced renal cell carcinoma. The OMNIVORE trial investigated a response-adaptive strategy, including treatment discontinuation in early nivolumab responders (Arm A) and salvage ipilimumab addition in non-responders (Arm B). Here we report outcomes with extended follow-up. Methods OMNIVORE was a phase II response-adaptive trial in which patients received induction nivolumab monotherapy. Patients achieving a confirmed complete or partial response discontinued nivolumab and entered observation (Arm A), while patients with stable disease or progressive disease received two doses of ipilimumab added to ongoing nivolumab (Arm B). This analysis characterizes long-term overall survival across the full study cohort and durability of response among patients who discontinued nivolumab following an early objective response. Results Of 83 patients who initiated treatment, 12 (14%) were allocated to Arm A and 57 (69%) to Arm B, with a median follow-up among living patients of 59.4 months (range 29.1–85.4 months) in Arm A and 31.4 months (range 4.6–62.6 months) in Arm B. The 3-year overall survival rate from nivolumab initiation was 64% (95% CI 51% to 74%) in the overall cohort, 83% (95% CI 48% to 96%) in Arm A, and 63% (95% CI 47% to 76%) in Arm B. Of the 12 Arm A patients, 6 (50%) remained off nivolumab at 1 year following treatment discontinuation, of whom 5 maintained responses beyond 43 months off therapy, with all remaining alive at last known follow-up, with overall survival ranging from 48.8 to 85.4 months from nivolumab initiation. Of the six patients who resumed treatment, only one achieved a durable complete response remaining on treatment at 83.2 months from nivolumab initiation. All 57 Arm B patients discontinued treatment with a median treatment duration of 3.7 months (range 1–24.8 months) and a median progression-free survival from nivolumab plus ipilimumab initiation of 4.6 months (95% CI 2.7 to 6.5 months). Conclusions With extended follow-up, a meaningful subset of patients achieving an early objective response to nivolumab maintained prolonged treatment-free survival following a short course of treatment. Salvage ipilimumab in nivolumab non-responders demonstrated limited benefit, reinforcing that upfront concurrent dual checkpoint blockade remains the preferred approach. Trial registration number NCT03203473 .

Abstract Purpose: This multicenter, single-arm, phase II trial evaluated the safety and efficacy of cabazitaxel and carboplatin followed by abiraterone, plus androgen deprivation therapy (ADT), in patients with high-volume metastatic castration-sensitive prostate cancer (mCSPC). Patients and Methods: Eligible patients had high-volume mCSPC and ≤3 months of prior ADT. Patients received six 21-day cycles of cabazitaxel (20 mg/m2) and carboplatin (AUC 4) with continuous ADT, followed by maintenance abiraterone (1,000 mg daily) and prednisone (5 mg daily). The primary endpoint was the proportion of patients free of prostate-specific antigen (PSA) or radiographic progression at 12 months. Secondary endpoints included complete PSA response (≤0.2 ng/mL), objective response, progression-free survival (PFS), and safety. Overall survival (OS) was also reported. Results: Sixty-one participants were enrolled at eight sites. The median age was 64 years, median baseline PSA was 6.6 ng/mL (0.07–745.7 ng/mL), 73.3% had Gleason grade group 5, 69.5% had 10 or more metastases, and 19.6% had a homologous recombination repair (HRR) mutation. PSA PFS at 12 months was 84.6% [95% confidence interval (CI), 72.5%–91.7%], and OS at 12 months was 94.8% (84.7%–98.3%). Complete PSA response was 66.7%, and complete objective response was 30.7%. Contrary to our hypothesis, relative to HRR wild-type patients, HRR-mutated patients (19.6%) had numerically fewer complete PSA responses (33.3% vs. 70.3%) and inferior PFS (HR, 2.43; 95% CI, 0.93–6.39). Common side effects of this quadruplet regimen included fatigue, nausea, and diarrhea. Conclusions: Cabazitaxel and carboplatin followed by abiraterone, together with ADT, were feasible, safe, and efficacious in patients with high-volume mCSPC and warrant further study in larger randomized trials.

162 Background: Clinical trial conduct in advanced prostate cancer has changed dramatically with the continued development of new imaging approaches, molecular phenotypes and genetic subtypes, prognosis assessments, and effective therapies across a range of disease states. This created a need to redefine terminology and best practices for clinical trials. Methods: We convened PCWG4, an international expert committee of multidisciplinary working groups, between 2016 and 2025 to update and expand PCWG2-3 recommendations based on emerging evidence and clinical trial data in an innovative biomarker and imaging context to provide guidance for clinical trial design, eligibility, and endpoint assessments. Results: PCWG4 redefines terminology around disease states and prior therapies in a patient-centric context, considering imaging modalities, with a particular focus on PET-defined disease. New recommendations are provided for disease state terminology, defining eligibility criteria, imaging and non-imaging-based responses. We define delay/prevent endpoints including responses by pathology, ctDNA, circulating tumor cells, and PSA declines, and specify intervals for re-assessments including imaging, biomarker assessments, and patient reported outcomes. We propose new imaging-specific rPFS criteria including guidance with serial PSMA PET/CT imaging (Table). We provide recommendations in a biomarker-based context for the indication, reflective of patient benefit for specific interventions. We emphasize the need for development of validated PET imaging and molecular and phenotypic criteria as well as trial designs to appropriately risk stratify patients, predict and assess benefit, and measure post-treatment outcomes reliably in a trial framework. Conclusions: PCWG4 expands guidance on patient and tumor profiling, as well as therapy development, to include both androgen deprivation therapy sensitive and resistant settings, reflecting today’s more heterogeneous and diverse patient population to optimize outcomes. PCWG4-defined radiographic progression by imaging modality for patients with metastatic disease. Pretreatment Scan On-treatment Scan #1(≥week 8) On-treatment Scan #2 All Subsequent Scans Bone scintigraphy Comparator Comparator for subsequent scansPOD never called here POD:PCWG3 criteria (2+2 additional new lesions) POD:≤5 new lesions: PCWG3 criteria 2 new lesions confirmed≥6 new lesions CT/MRI Any measurable disease Comparator PCWG3/RECIST PCWG3/RECIST PCWG3/RECIST PSMA PET Bones, and lymph nodes and lung metastases (non-RECIST qualifying by + on PET only) Comparator POD:≤5 new lesions: 2 new lesions confirmed on a subsequent scan≥6 new lesions Same as prior Same as prior Liver and non-pulmonary viscera Comparator POD:Any single new lesion that represents disease Same as prior Same as prior

PURPOSE The continuous development of new imaging approaches, molecular phenotyping, genetic subtypes, prognosis assessments, and effective therapies across a range of disease states has created a need to redefine terminology and best practices for clinical trial conduct in patients with advanced prostate cancer. Methods We convened an international expert committee of diverse working groups, the Prostate Cancer Working Group 4 (PCWG4), between 2016 and 2025. Our objective was to formulate updated criteria based on emerging evidence and clinical trial data in a biomarker context to provide guidance for clinical trial design, eligibility, and end point assessments for patients with advanced prostate cancer. RESULTS PCWG4 redefines terminology around the disease state and previous therapies in a patient-centric context and terminology focused on androgen pathway modulation. We consider imaging, with a particular focus on positron emission tomography (PET)–defined disease. New recommendations are provided for disease state terminology, defining eligibility criteria, response and delay/prevent end points, intervals for reassessments including imaging, and patient-reported outcome determination. We provide recommendations in a biomarker-based context of use for the intended indication, reflective of patient benefit for specific interventions. We emphasize the need for development of validated PET imaging and molecular and phenotypic criteria as well as trial designs to appropriately risk stratify patients, predict and assess benefit, and measure post-treatment outcomes reliably in a trial framework. CONCLUSION PCWG4 updates recommendations on patient and tumor characterization, therapy development, and imaging criteria and extends guidance into earlier androgen pathway modulator–naïve/sensitive disease states to reflect an evolving, heterogeneous, and diverse patient population to optimize treatment benefits for all patients.

AbstractBackgroundThe use of electronic health record (EHR) data for research is limited by a lack of structure and a standard data model. The objective of the ICAREdata (Integrating Clinical Trials and Real‐World Endpoints Data) project was to structure key research data elements in EHRs using a minimal Common Oncology Data Elements (mCODE) data model to extract and transmit data.MethodsThe ICAREdata project captured two EHR data elements essential to clinical trials: cancer disease status and treatment plan change. The project was implemented in clinical sites participating in Alliance for Clinical Trials in Oncology trials. Data were extracted from EHRs and sent by secure Fast Healthcare Interoperability Resource messaging (a standard for exchanging EHRs) to a database. Selected elements were compared with corresponding data from the trial's electronic data capture (EDC) system, Medidata Rave.ResultsBy December 2023, data were extracted and transmitted from 10 sites for 35 patients, involving 367 clinical encounters across 15 clinical trials. Data through March 2023 demonstrated that concordance for the elements treatment plan change and cancer disease status was 79% and 34%, respectively. When disease evaluation was reported by both EHR and EDC (n = 15), there was 87% agreement on cancer disease status.ConclusionsDocumentation, extraction, and aggregation of structured data elements in EHRs using mCODE and ICAREdata methods is feasible in multi‐institutional cancer clinical trials. EDC as a reference data set allowed assessment of the completeness of EHR data capture. Future initiatives will focus on elements with shared definitions in clinical and research environments and efficient workflows.Plain Language Summary Clinical trials use electronic case report forms to report data, and data must be manually entered on these forms, which is costly and time consuming. ICAREdata methods use structured, organized data from clinical trials that can be more easily shared instead having to enter free text into electronic health records.

5071 Background: Best treatment of mCSPC involves doublet therapy (ADT + novel hormonal agent) or triplet therapy (ADT + novel hormone + docetaxel); however, opportunity remains for further improvement. Studies show that homologous recombination repair (HRR) gene mutations are enriched in metastatic prostate cancer, and may portend resistance to docetaxel. CASCARA tested quadruplet therapy (ADT + cabazitaxel/carboplatin + abiraterone) in high-volume mCSPC, aiming to enhance PSA responses and decrease progression at 1 year. Methods: This phase 2 study enrolled 61 mCSPC patients with high-volume disease who received ADT plus cabazitaxel (20 mg/m2 q21d x 6) and carboplatin (AUC=4 q21d x 6) followed by abiraterone (1000 mg, plus prednisone 5 mg). Primary endpoint was freedom from PSA/radiographic progression at 1 year. Other endpoints included PSA50 response, freedom from PSA progression, and safety. Archival biopsies were retrospectively evaluated for HRR ( BRCA1/2, ATM, CHEK2, CDK12, BRIP1, RAD51B) mutations at a CLIA-certified lab. A sample size of 61 was determined using a Simon two-stage design (stage 1: 32 men, stage 2: 29 men) with a null hypothesis of a 1-year PSA/radiographic progression-free rate of 0.80 against a one-sided alternative of 0.92. Results: From 11/2019 to 06/2022, 61 men enrolled at 7 sites. Median age was 64 (range, 45–76) years; 21% were African American. Median baseline PSA was 8.9 (range, 0.1–1021) ng/mL. 44% of men had ECOG=1. 91% had Gleason sum 8–10. Prevalence of DNA alterations (50 evaluable pts) was 18% for HRR mutations, 38% for TP53 muts, 22% for ERG fusions, 10% for SPOP muts. Freedom from PSA/radiographic progression at 1 year was 77% (95% CI, 63–87%), and freedom from PSA progression at 1 year was 81% (95% CI, 67–90%). The PSA50 rate response was 97%. PSA ≤0.2 ng/mL at month-7, a surrogate for survival in other mCSPC studies, was 61%; PSA ≤4 ng/mL at month-7 was 82%. Outcomes according to mutation status are shown. AEs included 7% grade (Gr)-3/4 myelosuppression, 8% Gr-3/4 infections, 10% Gr-3 GI disorders, and 3% Gr-3 fatigue. There were 4 treatment-related discontinuations. Conclusions: Quadruplet therapy with ADT + cabazitaxel/carboplatin + abiraterone was well tolerated. At 1 year, 77% of pts were progression-free. PSA ≤0.2 ng/mL at month-7 was 61%, exceeding the historical month-7 PSA ≤0.2 ng/mL rate of 45% in CHAARTED–docetaxel arm. Further exploration of this quadruplet strategy in randomized phase III studies is warranted. Clinical trial information: NCT03934840 . [Table: see text]

PURPOSE The combination of gemcitabine and cisplatin (GC) is a standard therapy for metastatic urothelial carcinoma. Based on data that angiogenesis plays a role in urothelial carcinoma growth and progression, a randomized placebo-controlled trial was performed with the primary objective of testing whether patients treated with GC and bevacizumab (GCB) have superior overall survival (OS) than patients treated with GC and placebo (GCP). PATIENTS AND METHODS Between July 2009 and December 2014, 506 patients with metastatic urothelial carcinoma without prior chemotherapy for metastatic disease and no neoadjuvant or adjuvant chemotherapy within 12 months were randomly assigned to receive either GCB or GCP. The primary end point was OS, with secondary end points of progression-free survival, objective response, and toxicity. RESULTS With a median follow-up of 76.3 months among alive patients, the median OS was 14.5 months for patients treated with GCB and 14.3 months for patients treated with GCP (hazard ratio for death = 0.87; 95% CI, 0.72 to 1.05; two-sided stratified log-rank P = .14). The median progression-free survival was 8.0 months for GCB and 6.7 months for GCP (hazard ratio = 0.77; 95% CI, 0.63 to 0.95; P = .016). The proportion of patients with grade 3 or greater adverse events did not differ significantly between both arms, although increased bevacizumab-related toxicities such as hypertension and proteinuria occurred in the bevacizumab-treated arm. CONCLUSION The addition of bevacizumab to GC did not result in improved OS. The observed median OS of about 14 months is consistent with prior phase III trials of cisplatin-based chemotherapy.

BackgroundSystemic therapy (ST) can be deferred in patients who have metastatic renal cell carcinoma (mRCC) and slow‐growing metastases. Currently, this subset of patients managed with active surveillance (AS) is not well described in the literature.MethodsThis was a prospective observational study of patients with mRCC across 46 US community and academic centers. The objective was to describe baseline characteristics and demographics of patients with mRCC initially managed by AS, reasons for AS, and patient outcomes. Descriptive statistics were used to characterize demographics, baseline characteristics, and patient‐related outcomes. Wilcoxon 2‐sample rank‐sum tests and χ2 tests were used to assess differences between ST and AS cohorts in continuous and categorical variables, respectively. Kaplan‐Meier survival curves were used to assess survival.ResultsOf 504 patients, mRCC was initially managed by AS (n = 143) or ST (n = 305); 56 patients were excluded from the analysis. Disease was present in 69% of patients who received AS, whereas the remaining 31% had no evidence of disease. At data cutoff, 72 of 143 patients (50%) in the AS cohort had not received ST. The median overall survival was not reached (95% CI, 122 months to not estimable) in patients who received AS versus 30 months (95% CI, 25‐44 months) in those who received ST. Quality of life at baseline was significantly better in patients who were managed with AS versus ST.ConclusionsAS occurs frequently (32%) in real‐world clinical practice and appears to be a safe and appropriate alternative to immediate ST in selected patients.

4563 Background: We previously reported no difference in favorable response rate (FRR) or PFS for TIP vs BEP. Here we present results of a pre-planned analysis of biomarkers of outcome. Methods: HCG and AFP were drawn on days 1 and 15 of each cycle and rates of decline classified as satisfactory [S] or unsatisfactory [US] by MSK (Motzer JCO 2007) and GETUG (Fizazi Lancet Oncol 2014) methods. IHC for ERCC1, RAD51, PARP1, HER-2, and p-AKT was performed on pre-treatment tumor samples. An H-score (0 – 300) was calculated for each stain (H = stain intensity [0 – 3] x % positive cells [0-100]). H-score and marker decline category were correlated with FRR (PR + CR) and PFS. Patients (pts) who received disease-stabilizing chemotherapy were excluded from marker analyses. Results: Of 91 pts, 80 did not receive disease-stabilizing treatment with 79 having sufficient marker values for analysis by the MSK method and 75 by GETUG. By MSK, 49 had S decline vs 30 US; by GETUG, 34 S vs 41 US. FRR and PFS were improved for pts with S vs US decline by both methods and remained significant by the MSK method when stratified by IGCCCG group (Table). IHC (n=77) quality was adequate in 71 to 73 pts (varied by stain) and was positive (H >0) for PARP in 68/73, ERCC1 in 54/71, RAD51 in 54/73, p-AKT in 5/72, and HER2 in 4/72. Only PARP1 was associated with outcome with worse PFS for the lowest expression tertile (H < 180; p=0.013). Conclusions: PARP1 expression and tumor marker decline rates, particularly by MSK method, were significantly associated with outcome to initial chemotherapy in int/poor risk GCT. Future trials incorporating marker decline into treatment allocation and validating the prognostic effect of PARP1 expression are warranted. Clinical trial information: NCT01873326. [Table: see text]