Cisplatin-ineligible Patients Research Articles

A Podcast on Platinum Eligibility and Treatment Sequencing in Platinum-Eligible Patients with Locally Advanced or Metastatic Urothelial Carcinoma.

The treatment landscape for patients with advanced urothelial carcinoma continues to evolve. Enfortumab vedotin plus pembrolizumab has received Food and Drug Administration approval based on recent phase 3 trial data showing superior efficacy compared with first-line platinum-based chemotherapy; however, its distinct toxicity profile may make it less suitable for some patients, and availability in some countries may be limited by cost considerations. Consequently, platinum-based chemotherapy is expected to remain an important first-line treatment option. Choice of platinum regimen (cisplatin- or carboplatin-based) is informed by assessment of clinical characteristics, including performance status, kidney function, and presence of peripheral neuropathy or heart failure. For patients without disease progression after completing platinum-based chemotherapy, avelumab first-line maintenance treatment is recommended by international guidelines. For patients who have disease progression, pembrolizumab is the preferred approach. Additionally, following results from a recent phase 3 trial, nivolumab plus cisplatin-based chemotherapy has also received Food and Drug Administration approval and is an additional first-line treatment option for cisplatin-eligible patients. Later-line options for patients with advanced urothelial carcinoma, depending on prior treatment, may include enfortumab vedotin, erdafitinib (for patients with FGFR2/3 mutations or fusions/rearrangements), sacituzumab govitecan, and platinum rechallenge. For the small proportion of patients ineligible for any platinum-based chemotherapy (i.e., unsuitable for cisplatin or carboplatin), immune checkpoint inhibitor monotherapy with pembrolizumab or atezolizumab is a first-line treatment option, although approved agents vary between countries. In summary, this podcast discusses recent developments in the treatment landscape for advanced urothelial carcinoma, eligibility for platinum-based chemotherapy, potential first-line treatment options, and treatment sequencing. Supplementary file1 (MP4 246907 KB).

Study EV-103: Neoadjuvant treatment with enfortumab vedotin monotherapy in cisplatin-ineligible patients with muscle invasive bladder cancer (MIBC)—2-year event-free survival and safety data for Cohort H.

4564 Background: For patients (pts) with MIBC who are cisplatin-ineligible and undergoing radical cystectomy and pelvic lymph node dissection (RC+PLND), no neoadjuvant treatment options have been shown to improve survival. Enfortumab vedotin (EV) is an antibody-drug conjugate directed to Nectin-4, which is highly expressed in urothelial cancer. EV, alone and in combination w/ pembrolizumab, has been shown to improve OS vs chemotherapy in pts with previously treated and untreated locally advanced or metastatic urothelial cancer, respectively (Powles NEJM 2021; Powles ESMO 2023). In Cohort H of the EV-103 phase 1b/2 study, promising results for 1-year EFS and antitumor activity, including pathological complete response (pCR) and pathological downstaging (pDS) rates, were achieved in cisplatin-ineligible pts with MIBC after neoadjuvant monotherapy EV treatment (Petrylak ASCO GU 2022; Flaig ASCO 2023). Here we report updated results, including 2-year EFS. Methods: Cohort H of the EV-103 study enrolled cisplatin-ineligible pts with MIBC (T2-T4aN0M0) and ECOG PS ≤2 who were eligible for RC+PLND. Pts received neoadjuvant EV (1.25 mg/kg) on Days 1 and 8 every 21 days for 3 cycles before undergoing RC+PLND. The primary endpoint was pCR rate (ypT0 and N0) by central pathology review. Key secondary endpoints included pDS rate (ypT0, ypTis, ypTa, ypT1, and N0), safety, and EFS per investigator assessment (radiographic progression prior to RC, failure to undergo RC, gross residual disease at time of RC, recurrence, or death). Results: 22 pts (median age 74.5 years) were enrolled and treated; 15 pts (68.2%) remain on study. Pts had stage cT2 (68.2%), cT3 (27.3%), or cT4 (4.5%) disease. 68.2% of pts had urothelial carcinoma only; 31.8% had a mixed histology. 86.4% of pts completed all 3 cycles of EV; the median duration of EV treatment was 2.1 months (range 0.7-2.3). The pCR rate was 36.4% (95% CI, 17.2-59.3) and the pDS rate was 50.0% (95% CI, 28.2-71.8). The EFS rate at 24 months was 62.0% (95% CI, 38.2-78.9). Median EFS has not been reached. All pts underwent surgery with no delays due to EV-related TEAEs. The most common EV-related TEAEs were fatigue (45.5%), dysgeusia (36.4%), and alopecia (31.8%); 18.2% of pts had grade ≥3 EV-related TEAEs. 68.2% of pts had surgery-related TEAEs: the most common were procedural pain (18.2%), anemia (13.6%), and constipation (13.6%). 3 pts died due to AEs unrelated to EV treatment. 36.4% of pts received subsequent cancer-related therapy. Conclusions: Neoadjuvant EV monotherapy treatment showed promising results for antitumor activity and 2-year EFS with a manageable safety profile in cisplatin-ineligible pts with MIBC. These results support ongoing phase 2 and 3 programs in MIBC evaluating EV alone or combined with pembrolizumab (EV-103 Cohort L, KN-905/EV-303, KN-B15/EV-304). Clinical trial information: NCT03288545 .

SOGUG-NEOWIN: A phase 2, open-label, multi-centre, multi-national interventional trial evaluating the efficacy and safety of erdafitinib (ERDA) monotherapy and ERDA and cetrelimab (CET) as neoadjuvant treatment in patients with cisplatin-ineligible muscle-invasive bladder cancer (MIBC) whose tumours express FGFR gene alterations.

TPS4623 Background: The standard treatment for nonmetastatic MIBC is neoadjuvant cisplatin-based therapy followed by radical cystectomy (RC). However, many patients are ineligible for cisplatin. Immune checkpoint inhibitors (ICIs) have changed the treatment landscape for metastatic urothelial cancer (mUC), including for cisplatin-ineligible patients. Based on these results, ICIs are being explored as neoadjuvant treatment in resectable UC with preliminary data suggesting antitumour activity. ERDA is a Fibroblast Growth Factor Receptor (FGFR) inhibitor, which has shown efficacy in advanced UC with select FGFR2/3 mutations/fusions. ERDA plus cetrelimab demonstrated clinically meaningful activity in patients with newly diagnosed FGFR-altered mUC in the phase 2 NORSE trial. We hypothesize that ERDA plus cetrelimab will improve the pathological complete response (pCR) rate in patients with FGFR+ MIBC who are candidates for RC and are ineligible for or refuse neoadjuvant cisplatin-based therapy. Methods: SOGUG-NEOWIN is a prospective, non-comparative, open label, multicentre, international trial to assess the efficacy of 9 or 12 weeks of neoadjuvant ERDA (cohort 1) or the combination of cetrelimab and ERDA (cohort 2) in patients with MIBC (cT2-Ta N0/1 M0) and FGFR alterations. Key eligibility criteria include ECOG PS 0-1; pure or predominant UC histology; decline or ineligible for cisplatin-based chemotherapy as defined by one of the following criteria: impaired renal function (GFR < 60 mL/min), ≥ grade 2 hearing loss, or ≥ grade 2 peripheral neuropathy; patients are considered fit for cystectomy; no prior FGFR-targeted or anti-PD-(L)1 therapy; no prior systemic therapy, radiation or surgery (except TURBT or biopsies) for bladder cancer; prior BCG was allowed if completed ≥ 6 weeks before initiation of study treatment; no current retinopathy. A total of 45 patients will be allocated to each cohort by a centralized system. Co-primary endpoints are pCR rate and percentage of pathological downstaging response (<ypT2). Secondary endpoints include event-free survival, overall survival, overall response rate, safety, tolerability, and delay to surgery. Biomarkers of response and resistance will be assessed using baseline archival tissues, blood and urine. Quality of life (QoL) will be assessed using FACT-Bl and EQ-5D-5L. Tumour response assessment via PET-MRI will be performed in a subset of patients. The trial is approved in 4 countries. The first patient was included on 31-Jan-2024. This trial would be the first to systematically address whether ERDA ± cetrelimab improves pCR in patients with FGFR-positive MIBC. (EudraCT 2022-002586-15). Clinical trial information: 2022-002586-15.

Safety and efficacy of neoadjuvant chemotherapy with paclitaxel, carboplatin, and cetuximab for locally advanced head and neck squamous cell carcinoma.

As a substantial waiting time is usually required for radical surgery, safe and effective preoperative neoadjuvant chemotherapy (NAC) is desired for the treatment of locally advanced head and neck squamous cell carcinoma (HNSCC). However, the significance of NAC in advanced HNSCC is still unclear. This study aimed to assess the safety and efficacy of NAC using the paclitaxel, carboplatin, and cetuximab (PCE) regimen. We retrospectively evaluated the background characteristics, incidence of adverse events, overall response rate (ORR), pathological response, recurrence-free survival (RFS), and overall survival (OS) in 26 patients. Patients receiving the PCE regimen were further divided into two groups based on the number of chemotherapy cycles (one cycle or more) and eligibility for cisplatin. Patients aged ≥ 75years and those with an estimated glomerular filtration rate (eGFR) < 60mL/min were classified as ineligible for cisplatin. The median age was 70 (27-81) years. The median eGFR at treatment initiation was 63.2 (41.1-89.7)mL/min. Fourteen (53.8%) patients were ineligible for cisplatin. Grade 3 or higher neutropenia was observed in 11 of 25 (42.3%) patients. No delay in or withdrawal from surgery was observed. The ORR was 65.4%. The 2-year RFS and OS were 61.5% and 76.7%, respectively. No significant differences in safety and efficacy between the number of chemotherapy cycles and cisplatin eligibility were observed. NAC using the PCE regimen for patients with locally advanced HNSCC, including cisplatin-ineligible patients, has acceptable toxicity and favorable efficacy.

The evolving treatment landscape of metastatic urothelial cancer.

Cisplatin-based chemotherapy is currently the first-line standard of care for patients with metastatic urothelial cancer (mUC); however, up to 50% of patients are ineligible for cisplatin, necessitating alternative treatment options. Immune checkpoint inhibitors have been shown to be effective in cisplatin-ineligible patients. However, despite advances in the first-line setting, the prognosis remains poor, and challenges persist in selecting optimal therapies, treatment sequences and combination regimens. Maintenance therapy with avelumab revealed improved overall (OS) and progression-free survival (PFS) compared with best supportive care alone in patients with platinum-responsive mUC. Antibody-drug conjugates and targeted therapy with fibroblast growth factor receptor (FGFR) inhibitors have shown promise in selected patients, particularly in patients with metastatic disease that has progressed despite platinum-based chemotherapy. At the European Society of Medical Oncology Congress in 2023, groundbreaking results were presented from two phase III trials, EV-302/KEYNOTE-A39 and CheckMate 901, focusing on previously untreated mUC. In the former, the combination of enfortumab vedotin and pembrolizumab showed significant improvements in OS, PFS and overall response rate compared with chemotherapy alone; the combination of nivolumab with gemcitabine-cisplatin chemotherapy demonstrated a significant extension in median OS, PFS and overall response rate compared with chemotherapy alone. Inaddition, erdafitinib therapy resulted in significantly longer OS than chemotherapy among patients with mUC and FGFR alterations after previous treatment with immune checkpoint inhibitors. This comprehensive summary of the current treatment landscape for mUC incorporates clinical trial evidence and discussion of agents that are currently under investigation to provide support for clinical decision making and understanding of future therapeutic approaches.

Comparing survival in trial- versus routine-care advanced urothelial cancer patients on immune checkpoint blockade.

Although recent trials involving first-line immune checkpoint inhibitors have expanded treatment options for patients with advanced urothelial carcinoma (aUC) who are ineligible for standard cisplatin-based chemotherapy, there exists limited evidence for whether trial efficacy translates into real-world effectiveness for patients seen in routine care. This retrospective cohort study compares differences in overall survival (OS) between KEYNOTE-052 trial participants and routine-care patients receiving first-line pembrolizumab monotherapy. A routine-care patient cohort was constructed from the Flatiron Health database using trial eligibility criteria and was weighted to balance EHR and trial patient characteristics using matching-adjusted indirect comparisons. The routine-care cohort was older, more likely to be female, and more often cisplatin-ineligible due to renal dysfunction. ECOG performance status was comparable between the cohorts. Median OS was 9 months (95% CI 7-16) in the weighted routine-care cohort and 11.3 months (9.7-13.1) in the trial cohort. No significant differences between the Kaplan-Meier OS curves were detected (p = 0.76). Survival probabilities were similar between the weighted routine-care and trial cohorts at 12-, 24-, and 36- months (0.45 vs. 0.47, 0.31 vs. 0.31, 0.26 vs. 0.23, respectively). Notably, routine care patients had modestly lower survival at 3 months compared to trial participants (0.69 vs. 0.83, respectively). Our results provide reassurance that cisplatin-ineligible aUC patients receiving first-line immunotherapy in routine care experience similar benefits to those observed in trial patients.

Abstract 1902: ADRX-0706 Nectin-4 antibody-drug conjugate PK/PD characterization elucidates its widened therapeutic window

Abstract Nectin-4 is a well validated tumor target, which is highly expressed in several solid cancers, while expression in normal tissues is limited. A first-generation antibody-drug conjugate targeting Nectin-4, called enfortumab vedotin-ejfv (EV), was granted accelerated FDA approval in 2019 for urothelial cancers, and is currently approved for frontline therapy in cisplatin-ineligible patients with locally advanced or metastatic urothelial carcinoma, providing groundbreaking improvement in patient survival. However, clinical use of EV has also revealed safety-driven limitations, which result in reduced and/or interrupted drug exposures impacting efficacy. To overcome these limitations in therapeutic window, Adcentrx has developed ADRX-0706, a Nectin-4-targeting next-generation ADC with a drug-antibody ratio (DAR) of 8. ADRX-0706 utilizes a novel tubulin inhibitor payload AP052 with a proprietary cleavable linker utilizing Adcentrx’ proprietary i-ConjugationTM technology, which results in excellent biophysical features. Most noteworthy, ADRX-0706 displays a very stable PK profile with overlapping curves for total antibody and ADC as well as full DAR retention in circulation as determined by mass spectrometry. This translates to superior efficacy of ADRX-0706 over EV in multiple in vivo cancer cell line- and patient-derived xenograft mouse models across indications. Detailed PK/PD characterization of ADRX-0706 validates the mechanism of action as an anti-mitotic agent inducing cell cycle arrest and apoptosis. In addition, ADRX-0706 treatment leads to increased PD-L1 expression in mouse pharmacology models, which is a consequence of immunogenic cell death as described for this payload class. These findings are in line with emerging data on EV and provide rationale for combination regimens with checkpoint inhibitors. Besides the improvement in efficacy, ADRX-0706 was also designed for superior safety. A payload distribution study in tumor-bearing mice reveals a preferential and increased delivery of payload to tumors and lower payload delivery to normal tissues as well as lower free payload levels in plasma for ADRX-0706 compared to EV. Taken together, these data provide association of the improved drug-linker stability of ADRX-0706 to an improved Nectin-4 directed delivery of AP052 payload to the tumor and lower exposure in normal tissues, which may translate to an improved therapeutic window. In summary, the preclinical efficacy and safety properties of ADRX-0706 support clinical evaluation of this next generation anti-Nectin-4 ADC. ADRX-0706 is currently in a phase 1a/b study (NCT06036121). Citation Format: Maria Shahmoradgoli, Andrew Hau, Dong Jun Lee, Anna Wang, Peter P. Challita, Oscar Betancourt, Wes Sisson, Mario M. Kuo, Kris Zhang, Albert Goldson, Sam Janssen, Paul Datta, Felipe Acosta, Alexander Chu-Kung, Hui Li, Pia M. Challita-Eid, Sabine Rottmann. ADRX-0706 Nectin-4 antibody-drug conjugate PK/PD characterization elucidates its widened therapeutic window [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1902.

Abstract 1891: Preclinical characterization of ADRX-0706: A next-generation anti-Nectin-4 antibody-drug conjugate with improved therapeutic window

Abstract Nectin-4 is a well validated tumor target, which is highly expressed in several solid cancers such as urothelial, head-and-neck, breast, lung, pancreatic, ovarian, and cervical cancer, while expression in normal tissues is limited. A first-generation antibody-drug conjugate targeting Nectin-4, called enfortumab vedotin-ejfv (EV), was granted accelerated FDA approval in 2019 for urothelial cancers, and is currently approved for frontline therapy in cisplatin-ineligible patients with locally advanced or metastatic urothelial carcinoma, providing groundbreaking improvement in patient survival. However, clinical use of EV has also revealed safety-driven limitations, which result in reduced and/or interrupted drug exposures impacting efficacy. To overcome these limitations in therapeutic window and to maximize on the potential of Nectin-4 as a tumor target beyond urothelial cancers, Adcentrx has developed ADRX-0706, a Nectin-4-targeting next-generation ADC with a drug-antibody ratio of 8. ADRX-0706 is comprised of a novel fully human IgG1k monoclonal antibody linked to an optimized tubulin inhibitor payload AP052 through a proprietary cleavable linker. ADRX-0706 has strong binding affinity and selectively induces cytotoxicity in Nectin-4-expressing tumor cells. Importantly, ADRX-0706 is designed to have improved bystander effect, which allows tumor regression even in cases of heterogeneous Nectin-4 expression. This translates to superior in vivo efficacy of ADRX-0706 over EV in multiple mouse xenograft models of other indications beyond bladder cancer. In a mouse clinical trial of patient-derived cervical cancers with a range of Nectin-4 expression levels, ADRX-0706 reaches a 73% ORR. Since peripheral neuropathy is a main platform toxicity for this payload class, ADRX-0706 is assessed in an in vitro co-culture model to evaluate its neurotoxic potential. While EV displays a 75% decrease in neurite outgrowth, ADRX-0706 strikingly has no impact at concentrations up to 1mg/ml, suggesting a lower risk of peripheral neuropathy in humans for ADRX-0706. In preclinical repeat dose toxicology study, ADRX-0706 reaches an HNSTD of 18mg/kg in NHPs well above therapeutic exposures in mouse pharmacology studies, indicating a tremendous increase in the therapeutic index compared to EV. In summary, the highly selective and potent anti-tumor activity in multiple tumor types and wide preclinical therapeutic index of ADRX-0706 support clinical evaluation of this next generation anti-Nectin-4 ADC. ADRX-0706 is currently in a phase 1a/b study (NCT06036121). Citation Format: Andrew M. Hau, Maria Shahmoradgoli, Dong Jun Lee, Wes Sisson, Anna Wang, Peter P. Challita, Erin Nye, Mario M. Kuo, Alexis Mahloch, Monica Leung, Oscar Betancourt, Alexander Chu-Kung, Maojun Guo, Hui Li, Sabine Rottmann, Pia M. Challita-Eid. Preclinical characterization of ADRX-0706: A next-generation anti-Nectin-4 antibody-drug conjugate with improved therapeutic window [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1891.

Comparing the Efficacy of Carboplatin plus 5-Fluorouracil, Cisplatin plus 5-Fluorouracil, and Best Supportive Care for Advanced Esophageal Squamous Cell Carcinoma: A Propensity Score Analysis from a Tertiary Hospital in Southern Thailand.

Background: Although cisplatin plus 5-fluorouracil (5-FU) is the standard first-line treatment for advanced-stage esophageal squamous cell carcinoma (ESCC), carboplatin was substituted for cisplatin in cisplatin-ineligible patients. The efficacy of carboplatin plus 5-FU for advanced-stage ESCC remains unreported. Methods: This retrospective study analyzed first-line treatment-carboplatin plus 5-FU, cisplatin plus 5-FU, or best supportive care (BSC)-in advanced-stage ESCC patients at a tertiary hospital in Thailand (2012-2022). Survival was assessed using the Kaplan-Meier method, compared via the log-rank test, and adjusted through propensity score matching. Significance was set at p < 0.05. Results: Of 256 patients, 39.9% received carboplatin plus 5-FU, 27.7% cisplatin plus 5-FU, and 32.4% BSC. Carboplatin was significantly associated with older age, poorer performance status, more comorbidities, chronic kidney disease, and lower creatinine clearance. Median overall survival (OS) for carboplatin plus 5-FU, cisplatin plus 5-FU, and BSC was 8.05 (HR 0.31 [0.23, 0.43] vs. BSC, p < 0.001; HR 1.06 [0.78, 1.44] vs. cisplatin plus 5-FU, p = 0.7), 8.43, and 3.64 months, respectively. No significant OS difference was observed between carboplatin and cisplatin treatments after propensity score matching. Median progression-free survival (PFS) and objective response rates (ORR) showed no significant difference between carboplatin and cisplatin treatments. Conclusions: Despite less favorable baseline characteristics of patients receiving carboplatin plus 5-FU, this combination exhibited comparable OS, PFS, and ORR to cisplatin plus 5-FU in real-world scenarios. Furthermore, it significantly improved OS over BSC. Consequently, carboplatin plus 5-FU should be considered as an alternative regimen, particularly for advanced-stage ESCC patients who are ineligible for cisplatin.

XRay Vision: A Phase 3 Study of Xevinapant Plus Radiotherapy (RT) for High-risk, Cisplatin-ineligible Patients with Resected, Locally Advanced Squamous Cell Carcinoma of the Head and Neck (LA SCCHN)

XRay Vision: A Phase 3 Study of Xevinapant Plus Radiotherapy (RT) for High-risk, Cisplatin-ineligible Patients with Resected, Locally Advanced Squamous Cell Carcinoma of the Head and Neck (LA SCCHN)

Physicianreported treatment patterns and outcomes in metastatic bladder cancer in the USA: the CancerMPact® Survey 2020.

Aim: This study assessed physician-reported treatment patterns for metastatic bladder cancer. Materials & methods: A total of106 USA-based physicians were surveyed in 2020 using the CancerMPact® online survey. Results: Among cisplatin-eligible patients, 86.1% received first-line (1L) platinum-containing chemotherapy, most commonly cisplatin plus gemcitabine, and 9.8% received immune checkpoint inhibitor monotherapy. Among cisplatin-ineligible patients, 46.5% received 1L platinum-containing chemotherapy, most commonly carboplatin plus gemcitabine and 46.2% received 1L immune checkpoint inhibitor therapy. Approximately 44% of patients who received 1L treatment received second-line (2L) therapy after progression. Conclusion: Platinum-containing chemotherapy was the most widely reported 1L treatment approach. A high proportion of patients received no 2L therapy. Validation in an updated dataset is warranted following the practice-changing approvals of avelumab 1L maintenance and additional 2L options.

Neoadjuvant nivolumab (N) + ipilimumab (I) in cisplatin-ineligible patients with upper tract urothelial cancer (UTUC): Updated results.

645 Background: Perioperative platinum-based chemotherapy for UTUC improves pathologic responses and disease-free survival (DFS). We report the updated results from our on-going phase II neoadjuvant trial of N+I for cisplatin-ineligible patients (pts) with UTUC (NCT03520491). Methods: Cisplatin-ineligible pts with histologically confirmed high-grade UTUC and/or radiographically invasive UTUC with positive selective urine cytology were eligible. Pts were treated with I 3mg/kg + N 1mg/kg (weeks 0, 6), and “N” 3mg/kg (week 3) prior to radical nephroureterectomy (NU). The primary endpoint (EP) was pathologic complete response (pCR, ypT0pN0) and secondary EPs included &lt;ypT2pN0 rate, DFS, and toxicity. Next generation sequencing of pre-treatment tumors was correlated with pathologic response. Results: Seventeen pts (76% male) were enrolled between 2/2021-6/2023 with median age 73 (range 59-85). Primary sites included ureter in 10 pts, renal pelvis in 5 and both in 2. Median tumor diameter was 3.0 cm, (range: 1.5 - 4.2 cm), with 8 pts (47%) having hydronephrosis. To date, 11 pts (65%) have received all planned treatment, 6 pts had N+/-I stopped early due to treatment-related toxicities, 2 pts are pending NU, 13 pts have undergone NU, 1 declined surgery, and another progressed on N+I. A pCR was seen in 4/15 pts (27%) and &lt;ypT2pN0 in 9/15 (60%). Median time from last treatment to NU was 1.6 months (range 0.5-4.9). Three pts developed metastatic recurrence at 3.9, 10.3 and 15.6 months after treatment initiation. CTCAE grade ≥3 treatment-related adverse events occurred in 5 pts (29%). Four pts died during follow up: two of metastatic disease, one of complications related to a bowel leak (7.2 months after N+I initiation and 4.7 months after NU), and one from complications of a fall unrelated to disease or treatment (9.2 months after N+I initiation and 4.7 months after NU). Median tumor mutational burden (TMB) in 9 pts with pre-treatment sequencing was 13.2 mutations/mb (range 4.1-106.3), with 4/5 pts with TMB&gt;10 &lt;ypT2pN0 at NU. Pathogenic germline variants in mismatch repair genes were confirmed in 4 pts (MSH2 in 3, MLH1 in 1) and MSI-high tumors without germline alterations in 2 pts, with 5 of 6 completing NU (1 pending surgery); all 5 achieved pCR (n=3) or ypTaN0 (n=2) and remain alive and disease-free at last follow-up (6, 13.4, 17, 17.9 and 31 months). Conclusions: Updated findings from an on-going phase II trial of cisplatin-ineligible pts with UTUC receiving neoadjuvant N+I shows clinical activity in line with our initial results. All pts with pathogenic germline variants in mismatch repair genes or MSI-high tumors without germline alteration who underwent NU achieved &lt;ypT2pN0 and remain free of disease. Clinical trial information: NCT03520491 .

Phase I/II study of ipilimumab plus nivolumab (IPI-NIVO) combined with sacituzumab govitecan in patients with metastatic cisplatin-ineligible urothelial carcinoma.

TPS713 Background: Treatment options are suboptimal and limited for cisplatin-ineligible metastatic urothelial carcinoma (mUC) patients. Sacituzumab govitecan (SG) is a Trop-2 directed antibody-drug conjugate (ADC) coupled with SN-38 through a hydrolysable linker. In the phase II TROPHY-U-01 study, SG demonstrated an objective response rate (ORR) of 27% and median overall survival (OS) of 10.5 months in mUC patients who progressed after platinum-based chemotherapy and immune checkpoint inhibitors (ICI), receiving accelerated approval by the US FDA. In CheckMate 032 study, nivolumab 1 mg/kg plus ipilimumab 3 mg/kg (N1+I3) every 3 weeks (Q3W) x 4 cycles followed by nivolumab monotherapy 3mg/kg Q2W showed promising activity post-platinum that led to the ongoing phase III trial in the first-line setting (NCT03036098). Given potential synergism between immunogenic cell death induced by ADC and ICI, we hypothesized that the combination of SG and IPI-NIVO would benefit patients with manageable toxicities. We designed this study to assess the safety and clinical activity of IPI-NIVO with SG as first-line therapy for cisplatin-ineligible mUC patients. Methods: This is an ongoing phase I/II, single arm, multicenter study for cisplatin-ineligible mUC. The Phase I portion enrolled 9 patients using a 3+3 design with safety and RP2D as primary endpoints. In this part, patients received fixed doses of IPI-NIVO (N1+I3) IV Q3Wx 4 cycles combined with SG (DL1 8 mg/kg or DL2 10mg/kg) IV on days 1, 8 Q3W x 4 cycles. This was followed by maintenance nivolumab 360 mg IV Q3W with SG on days 1, 8 Q3W. The RP2D of SG was determined as 8 mg/kg and combination was deemed safe and tolerable. ORR is the primary endpoint in the ongoing phase II portion of the study using Simon 2 stage design (n=34) with a futility interim analysis after 13 patients. The null hypothesis of ORR ≤ 38% will be tested with a desirable ORR of &gt;60% under a statistical power of 80% and a one-sided type I error rate of 5%. Thirteen of the 34 patients have been enrolled and the study has passed the predefined interim analysis for futility. We aim to continue accrual. Exploratory biomarker analyses will be conducted using tumor and blood samples collected during screening and at progression. Clinical trial (NCT04863885). Clinical trial information: NCT04863885 .

Clinical efficacy of enfortumab-pembrolizumab combination therapy in locally advanced/metastatic urothelial carcinoma (UC): A real-world experience.

643 Background: The FDA approval of enfortumab (EV) and pembrolizumab (Pembro) combination therapy as a first-line treatment for cisplatin-ineligible patients with locally advanced/metastatic urothelial carcinoma (la/mUC) was based on the EV-103 trial. We aim to assess the clinical response rate of this combination therapy in our institution's patients with locally advanced and metastatic UC. Methods: This retrospective cohort study included 20 patients diagnosed with locally advanced/metastatic UC(la/mUC) who were treated with EV-Pembro combination for at least 2 cycles, from June 2022 to August 2023 at the Mayo Clinic. Patients who were treatment naïve or who progressed one or more lines of therapy were included in the study cohort. Main outcome of interest included imaging-based best overall response rate in terms of complete (CR) and partial (PR) response, stable disease (SD), and progressive disease (PD). Results: Out of 20 patients, the number of males and females were 16 (80%) and 4 (20%) respectively; the median age was 77 years (IQR: 51-92). 3 (15%) of patients had involvement of upper urinary tract disease along with bladder cancer. The common sites of visceral metastasis at the time of initial presentation include liver 2(10%), lung 6(30%) and lymph nodes12(60%). Common toxicities of this regimen included rash, pruritis, peripheral neuropathy, fatigue, transaminitis, dysgeusia, and diarrhea. The treatment was stopped in 10 (50%) patients due to completion of planned therapy (achieved CR or proceeded with resection of residual disease) (30%), 5 patients due to progression (50%), 1 patient due to therapy side effects (10%) and in 1 patient due to death (10%). The objective response was 45% (N =9); 5 (25%) had PR, and 4 (20%) had CR. A total of 2 (10%) had SD while 2 (10%) experienced PD. Histological correlation with clinical benefit is shown in the table. Conclusions: EV-Pembro combination therapy shows promising responses in patients who have progressed after previous lines of therapy, consistent with previously published data on EV 201 in small cohorts. However, ongoing expansion of this cohort and data from larger studies will help further elucidate survival benefits and their correlation with genetic testing. [Table: see text]

Comparative Effectiveness of Neoadjuvant Pembrolizumab Versus Cisplatin-based Chemotherapy or Upfront Radical Cystectomy in Patients with Muscle-invasive Urothelial Bladder Cancer

BackgroundRecent progresses in the use of immune checkpoint inhibitor (ICI) have challenged the therapeutic standards in patients with muscle-invasive urothelial bladder carcinoma (MIBC). ObjectiveTo compare neoadjuvant pembrolizumab followed by radical cystectomy (RC) versus neoadjuvant chemotherapy (NAC) and RC or upfront RC, according to cisplatin eligibility. Design, setting, and participantsWe conducted two separate analyses for cisplatin-eligible and cisplatin-ineligible cT2-4N0M0 MIBC patients. We used a propensity score adjustment that relied on inverse probability of treatment-weighting (IPTW). InterventionPembrolizumab within the PURE-01 trial, and NAC and RC or upfront RC from a high-volume tertiary care referral center. Outcome measurements and statistical analysisThe primary endpoint in both analyses was event-free survival (EFS), defined as freedom from recurrence, and/or death from any cause indexed from the date of treatment initiation or RC. The secondary endpoints included EFS in propensity score–matched patients, pathologic response rate, and recurrence-free survival (RFS) after RC. Results and limitationsA total of 458 patients who underwent RC, with or without NAC, at Moffitt Cancer Center between October 2005 and October 2020, and 146 patients enrolled in PURE-01 were analyzed. In cisplatin-ineligible patients, EFS was superior in those receiving pembrolizumab (p < 0.001). The estimated 3-yr EFS was 77.8% (95% confidence interval [CI]: 63.5–95.2) for pembrolizumab and RC, and 36.1% (95% CI: 28.6–45.5) for upfront RC. EFS remained superior in those receiving neoadjuvant ICI (NICI) following IPTW (p < 0.001). In cisplatin-eligible patients, EFS was superior in those receiving pembrolizumab and RC (p < 0.001). The estimated 3-yr EFS was 86.9% (95% CI: 80.9–93.3) for pembrolizumab and 63.5% (95% CI: 56.5–71.4) for NAC. EFS remained superior in those receiving NICI following IPTW (p < 0.001). Pathologic responses and RFS in pembrolizumab-treated patients were also superior to those in NAC-treated patients. Results are limited by the retrospective nature of the study. ConclusionsIn the first ever reported comprehensive comparison of outcomes between neoadjuvant ICI and NAC, followed by RC, or upfront RC, we report increased responses and improved oncologic outcomes with neoadjuvant ICI in patients with MIBC. Patient summaryWe compared the results obtained from the use of pembrolizumab and radical cystectomy with standard-of-care treatments in patients with bladder carcinoma infiltrating the muscle layer. We reported increased response and survival rates possibilities with the use of immunotherapy, anticipating the possibility to set new therapeutic standards in these patients, pending the results of ongoing randomized studies.

Enfortumab vedotin and pembrolizumab as new first-line standard for metastatic urothelial cancer

Treatment options for patients with metastatic urothelial carcinoma ineligible for cisplatin-based chemotherapy have historically been limited. O'Donnell etal. recently reported the results of EV-103 Cohort K,1 leading to accelerated approval of enfortumab vedotin and pembrolizumab for cisplatin-ineligible patients and raising additional questions of how to best utilize this effective regimen.

PrECOG PrE0807: A Phase 1b Feasibility Trial of Neoadjuvant Nivolumab Without and with Lirilumab in Patients with Muscle-invasive Bladder Cancer Ineligible for or Refusing Cisplatin-based Neoadjuvant Chemotherapy

Background and objectiveNeoadjuvant cisplatin-based chemotherapy prior to radical cystectomy (RC) improves overall survival (OS) in muscle-invasive bladder cancer (MIBC). However, many patients are cisplatin ineligible; therefore, new treatment options are needed. Nivolumab without/with lirilumab prior to RC was investigated in cisplatin-ineligible patients in this phase 1b trial (NCT03532451) to determine its safety/feasibility. MethodsPatients with localized MIBC received two doses of nivolumab (480 mg) alone (cohort 1) or with lirilumab (240 mg; cohort 2) prior to RC. Cohorts were enrolled sequentially. The key eligibility criteria were cT2-4aN0-1M0 stage and cisplatin ineligibility/refusal. The primary endpoint was the rate of grade (G) ≥3 treatment-related adverse events (TRAEs) as per Common Terminology Criteria for Adverse Events version 5.0. The key secondary endpoints included the proportion of patients who underwent RC >6 wk after the last dose, CD8+ T-cell density change between pretreatment transurethral resection of bladder tumor (TURBT) and post-treatment RC, ypT0N0, <ypT2N0 rates, 2-yr recurrence-free survival (RFS), and OS. Key findings and limitationsAmong 43 patients enrolled (n = 13, cohort 1; n = 30, cohort 2), 13 and 29 completed intended neoadjuvant therapy, respectively, in cohorts 1 and 2, and 41 underwent RC. The median time from the last dose to RC was 4 wk. The G3 TRAEs occurred in 0% (90% confidence interval [CI] 0–21%) of patients in cohort 1 and 7% (90% CI 1–20%) in cohort 2; all these TRAEs resolved and no G4/5 TRAEs occurred. No patient had delayed RC for >6 wk. In cohorts 1 and 2, ypT0N0 rates for patients with MIBC and RC were 17% and 21%, <ypT2N0 rates were 25% and 32%, 2-yr RFS rates were 73% and 71%, and 2-yr OS rates were 82% and 89%, respectively. CD8+ T-cell density increased significantly from TURBT to RC in cohort 2. Conclusions and clinical implicationsNeoadjuvant nivolumab-based immunotherapy was safe, feasible, and well tolerated in cisplatin-ineligible patients with MIBC. Although ypT0N0 rates were lower than expected, 2-yr survival rates seem to be comparable with those of other neoadjuvant immunotherapy trials. Nivolumab is being evaluated in the CA-017-078 trial (NCT03661320). Patient summaryFor patients with muscle-invasive bladder cancer unable to receive cisplatin-based chemotherapy, treatment with nivolumab without and with lirilumab prior to radical cystectomy was safe, feasible, and well tolerated. Nivolumab-based immunotherapy showed lower pathologic response rates than but similar survival rates to other neoadjuvant immunotherapy trials.

Healthcare costs associated with first-line (1L) treatment of patients with locally advanced or metastatic urothelial carcinoma (la/mUC) in the United States (US).

11 Background: In 2023 in the US, 82,290 new cases of bladder cancer and 16,670 related deaths were estimated. Prior analyses assessing the economic burden of la/mUC in the current and evolving treatment landscape have been limited. This study aimed to estimate the direct medical costs of treating patients with la/mUC, from US Medicare and commercial perspectives. Methods: A cost model was developed to estimate annual direct medical care costs in patients with la/mUC eligible for 1L platinum-based chemotherapy (PBC) in 2023. Costs (2023 USD)—including drug acquisition and administration, disease management and adverse event (AE) management—were calculated, including subsequent therapy costs. Inputs included estimated number of treated patients per year, treatment duration, progression-free survival and overall survival with various therapies, AEs incidence, and market shares. Efficacy and safety data were sourced from product prescribing information, epidemiology data from Surveillance, Epidemiology, and End Results (SEER) database and published literature. Market share assumptions were based on market research data. Results: For a hypothetical health plan with 1,000,000 members, 108 and 22 patients with la/mUC from Medicare and commercial perspectives, respectively, were estimated to be eligible for 1L PBC in 2023. Estimated total annual costs per treated patient are shown in the Table below. With market share data comprising 1L PBC, with and without avelumab (AVE) 1L maintenance (61% and 25%) and enfortumab vedotin (EV) + pembrolizumab (PEM) (for cisplatin-ineligible patients, 14%), annual costs of $16,673,645 ($12,861 per treated member per month) and $4,637,226 ($17,852 per treated member per month) were estimated for Medicare and commercial perspectives, respectively. Drug acquisition costs in 1L represented most of the total costs (Medicare, 75%; commercial, 64%). Conclusions: Understanding the economic burden associated with la/mUC treatments may facilitate informed decision making on treatment choice and optimal sequencing. Further real-world studies are needed to assess the impact of these innovative treatments on disease and AE management costs of la/mUC. [Table: see text]

Overview, Diagnosis, and Perioperative Systemic Therapy of Upper Tract Urothelial Carcinoma.

Upper tract urothelial carcinoma comprises 5-10% of all urothelial carcinoma cases. This disease tends to have a more aggressive course than its lower urinary tract counterpart, with 60% of patients presenting with invasive disease and 30% of patients presenting with metastatic disease at diagnosis. The diagnostic workup of UTUC involves imaging with CT urogram, urine cytology, and direct visualization and biopsy of suspected lesions via ureteroscopy. Standard treatment of high-grade UTUC involves radical nephroureterectomy (RNU) and excision of the ipsilateral bladder cuff. Both the NCCN and EAU Guidelines include neoadjuvant chemotherapy as a treatment option for select patients with UTUC; however, there are no strict guidelines. Much of the rationale for neoadjuvant chemotherapy is based on extrapolation from data from muscle-invasive bladder cancer, which has demonstrated a 5-year OS benefit of 5-8%. Retrospective studies evaluating the use of NACT in urothelial carcinoma have yielded pathologic objective response rates of 48% in UTUC cohorts. The randomized Phase III POUT study noted a DFS advantage with adjuvant platinum-based chemotherapy, compared with surveillance in UTUC, of 70% vs. 51% at 2 years. Though not the standard of care, multiple studies have explored the use of perioperative immunotherapy or chemoimmunotherapy in the management of invasive urothelial carcinoma. The PURE-02 study explored the use of neoadjuvant pembrolizumab in patients with high-risk UTUC. A small study of 10 patients, it showed no significant signals of activity with neoadjuvant pembrolizumab. Another Phase II study of neoadjuvant ipilimumab and nivolumab in cisplatin-ineligible UTUC yielded more promising findings, with 3/9 patients attaining a pathologic CR and the remaining six pathologically downstaged. The ABACUS trial found a 31% pathologic complete response rate amongst cisplatin-ineligible MIBC patients treated with neoadjuvant atezolizumab. The use of adjuvant immunotherapy has been explored over three phase III trials. The CheckMate-274 trial found a DFS benefit with the addition of one year of adjuvant nivolumab in patients with high-risk urothelial carcinoma. The IMvigor-010 study of adjuvant atezolizumab was a negative study. The AMBASSADOR trial of adjuvant pembrolizumab is pending results. With the FDA approval of erdafitinib in metastatic urothelial carcinoma, similar targets have been explored for use in perioperative use in invasive urothelial carcinoma, as with adjuvant infigratinib in the PROOF-302 trial. As the treatment paradigm for urothelial carcinoma evolves, further prospective studies are needed to expand the perioperative treatment landscape of UTUC.

Outcomes after Contemporary Definitive Radiotherapy Alone in Patients with TNM-7 Stage III/IV Head and Neck Squamous Cell Carcinoma

This study was undertaken to determine outcomes and prognostic factors of definitive intensity-modulated radiotherapy (IMRT) alone for patients with TNM-7 stage III/IV HNSCC who did not receive concurrent chemotherapy. We evaluated TNM-7 stage III/IV HNSCC patients treated with definitive IMRT alone in our institution from 2004-2019. Patients were reclassified according to TNM-8 staging. Stage II HPV+ oropharyngeal cancers (OPC) were subdivided into T1-2N2 and T3N0-2 for analysis. The rationale for chemotherapy omission was obtained retrospectively from clinical documentation. Recurrence-free survival (RFS) and overall survival (OS) were estimated stratified by HPV status (determined by p16 staining, sometimes supplemented by HPV DNA testing). Multivariable analysis (MVA) identified prognostic factors for RFS and OS, taking into account stage and IMRT regimen. Age, performance status, and smoking were also examined for OS. A total of 1083 patients were included (460 HPV+ and 623 HPV-). Reasons for omission of chemotherapy were: age >70 years or frailty (n = 551, 51%), cisplatin contraindication (n = 241, 22%), patient refusal (n = 106, 10%), and clinician's decision (n = 185, 17%). Median age was 67 years for HPV+ and 70 years for HPV- cohorts. IMRT mostly utilized altered fractionation regimens (n = 1016, 94%): moderately accelerated (Acc) (70 Gy/35 fractions [f]/6 weeks [w], 55%), hypofractionated (Hypo) (60 Gy/25f/5w, 14%), and hyperfractionated-accelerated (Hyper) (64 Gy/40f/4w, 25%). Median follow-up was 5 years. Five-year RFS and OS for HPV+ TNM-8 stage I/T1-2N2/T3N0-N2/III were 89%/86%/76%/52% and 83%/80%/64%/33% respectively (p<0.01). The same outcomes for HPV- TNM-8 stage III/IVA/IVB were 58%/52%/39% and 47%/27%/13%, respectively (p<0.01). MVA confirmed that HPV+ T3N0-2 subset within stage II and stage III (vs stage I) had lower RFS, and HPV- stage IVA and IVB (vs stage III) carried worse RFS and OS (Table). Despite the retrospective nature and inherent selection bias, this large single institutional study shows that altered fractionated IMRT alone is an acceptable alternative for elderly, frail or cisplatin ineligible patients with HPV+ stage I/IIA (T1-2N2) OPC. Patients with HPV+ T3N0-2/stage III OPC and HPV- stage III/IV HNSCC have poor outcomes with IMRT alone and may benefit from alternative strategies.