Impact of teratoma on survival probabilities of patients with metastatic non-seminomatous germ cell cancer: Results from the IGCCCG Update Consortium

AIMS

To resolve the ongoing controversy surrounding the impact of teratoma (TER) in the primary among patients with metastatic testicular non-seminomatous germ-cell tumours (NSGCT).

PATIENTS AND METHODS

Using the International Germ Cell Cancer Collaborative Group (IGCCCG) Update Consortium database, we compared the survival probabilities of patients with metastatic testicular GCT with TER (TER) or without TER (NTER) in their primaries corrected for known prognostic factors. Progression-free survival (5y-PFS) and overall survival at 5 years (5y-OS) were estimated by the Kaplan-Meier method.

RESULTS

Among 6792 patients with metastatic testicular NSGCT, 3224 (47%) had TER in their primary, and 3568 (53%) did not. In the IGCCCG good prognosis group, the 5y-PFS was 87.8% in TER versus 92.0% in NTER patients (p = 0.0001), the respective 5y-OS were 94.5% versus 96.5% (p = 0.0032). The corresponding figures in the intermediate prognosis group were 5y-PFS 76.9% versus 81.6% (p = 0.0432) in TER and NTER and 5y-OS 90.4% versus 90.9% (p = 0.8514), respectively. In the poor prognosis group, there was no difference, neither in 5y-PFS [54.3% in TER patients versus 55.4% (p = 0.7472) in NTER], nor in 5y-OS [69.4% versus 67.7% (p = 0.3841)]. NSGCT patients with TER had more residual masses (65.3% versus 51.7%, p < 0.0001), and therefore received post-chemotherapy surgery more frequently than NTER patients (46.8% versus 32.0%, p < 0.0001).

CONCLUSION

Teratoma in the primary tumour of patients with metastatic NSGCT negatively impacts on survival in the good and intermediate, but not in the poor IGCCCG prognostic groups.

A plain language summary of the TROPHY-U-01 study: sacituzumab govitecan use in people with locally advanced or metastatic urothelial cancer

WHAT IS THIS SUMMARY ABOUT?

Sacituzumab govitecan (brand name: TRODELVY®) is a new treatment being studied for people with a type of bladder cancer, called urothelial cancer, that has progressed to a locally advanced or metastatic stage. Locally advanced and metastatic urothelial cancer are usually treated with platinum-based chemotherapy. Metastatic urothelial cancer is also treated with immune checkpoint inhibitors. There are few treatment options for people whose cancer gets worse after receiving these treatments. Sacituzumab govitecan is a suitable treatment option for most people with urothelial cancer because it aims to deliver an anti-cancer drug directly to the cancer in an attempt to limit the potential harmful side effects on healthy cells. This is a summary of a clinical study called TROPHY-U-01, focusing on the first group of participants, referred to as Cohort 1. All participants in Cohort 1 received sacituzumab govitecan.

WHAT ARE THE KEY TAKEAWAYS?

All participants received previous treatments for their metastatic urothelial cancer, including a platinum-based chemotherapy and a checkpoint inhibitor. The tumor in 31 of 113 participants became significantly smaller or could not be seen on scans after sacituzumab govitecan treatment; an effect that lasted for a median of 7.2 months. Half of the participants were still alive 5.4 months after starting treatment, without their tumor getting bigger or spreading further. Half of them were still alive 10.9 months after starting treatment regardless of tumor size changes. Most participants experienced side effects. These side effects included lower levels of certain types of blood cells, sometimes with a fever, and loose or watery stools (diarrhea). Side effects led 7 of 113 participants to stop taking sacituzumab govitecan.

WHAT WERE THE MAIN CONCLUSIONS REPORTED BY THE RESEARCHERS?

The study showed that sacituzumab govitecan had significant anti-cancer activity. Though most participants who received sacituzumab govitecan experienced side effects, these did not usually stop participants from continuing sacituzumab govitecan. Doctors can help control these side effects using treatment guidelines, but these side effects can be serious. Clinical Trial Registration: NCT03547973 (ClinicalTrials.gov) (TROPHY-U-1).

Sacituzumab Govitecan in Combination With Pembrolizumab for Patients With Metastatic Urothelial Cancer That Progressed After Platinum-Based Chemotherapy: TROPHY-U-01 Cohort 3

PURPOSE

Pembrolizumab is standard therapy for patients with metastatic urothelial cancer (mUC) who progress after first-line platinum-based chemotherapy; however, only approximately 21% of patients respond. Sacituzumab govitecan (SG) is a trophoblast cell surface antigen-2-directed antibody-drug conjugate with US Food and Drug Administration-accelerated approval to treat patients with locally advanced or mUC who previously received platinum-based chemotherapy and a checkpoint inhibitor (CPI). Here, we report the primary analysis of TROPHY-U-01 cohort 3.

METHODS

TROPHY-U-01 (ClinicalTrials.gov identifier: NCT03547973) is a multicohort, open-label phase II study. Patients were CPI-naïve and had mUC progression after platinum-based chemotherapy in the metastatic setting or ≤12 months in the (neo)adjuvant setting. Patients received 10 mg/kg of SG once on days 1 and 8 and 200 mg of pembrolizumab once on day 1 of 21-day cycles. The primary end point was objective response rate (ORR) per central review. Secondary end points included clinical benefit rate (CBR), duration of response (DOR) and progression-free survival (PFS) per central review, and safety.

RESULTS

Cohort 3 included 41 patients (median age 67 years; 83% male; 78% visceral metastases [29% liver]). With a median follow-up of 14.8 months, the ORR was 41% (95% CI, 26.3 to 57.9; 20% complete response rate), CBR was 46% (95% CI, 30.7 to 62.6), median DOR was 11.1 months (95% CI, 4.8 to not estimable [NE]), and median PFS was 5.3 months (95% CI, 3.4 to 10.2). The median overall survival was 12.7 months (range, 10.7-NE). Grade ≥3 treatment-related adverse events occurred in 61% of patients; most common were neutropenia (37%), leukopenia (20%), and diarrhea (20%).

CONCLUSION

SG plus pembrolizumab demonstrated a high response rate with an overall manageable toxicity profile in patients with mUC who progressed after platinum-based chemotherapy. No new safety signals were detected. These data support further evaluation of SG plus CPI in mUC.

Deep and Durable Prostate-specific Antigen Response to Darolutamide with Androgen Deprivation Therapy and Docetaxel, and Association with Clinical Outcomes for Patients with High- or Low-volume Metastatic Hormone-sensitive Prostate Cancer: Analyses of the Randomized Phase 3 ARASENS Study

BACKGROUND AND OBJECTIVE

Addition of darolutamide to androgen deprivation therapy (ADT) and docetaxel significantly improved overall survival (OS) in ARASENS (NCT02799602). Here we report on prostate-specific antigen (PSA) responses and their association with outcomes.

METHODS

ARASENS is an international, double-blind, phase 3 study in patients with metastatic hormone-sensitive prostate cancer (mHSPC) randomized to darolutamide 600 mg orally twice daily (n = 651) or placebo (n = 654), both with ADT + docetaxel. The proportion of patients with undetectable PSA (<0.2 ng/ml) and time to PSA progression (≥25% relative and ≥2 ng/ml absolute increase from nadir) were compared between groups in prespecified exploratory analyses. PSA outcomes by disease volume and the association of undetectable PSA with OS and times to castration-resistant prostate cancer (CRPC) and PSA progression were assessed in post hoc analyses.

KEY FINDINGS AND LIMITATIONS

The proportion of patients with undetectable PSA at any time was more than doubled with darolutamide versus placebo, at 67% versus 29% in the overall population, 62% versus 26% in the high-volume subgroup, and 84% versus 38% in the low-volume subgroup. Darolutamide delayed time to PSA progression versus placebo, with hazard ratios of 0.26 (95% confidence interval [CI] 0.21-0.31) in the overall population, 0.30 (95% CI 0.24-0.37) in the high-volume subgroup, and 0.093 (95% CI 0.047-0.18) in the low-volume subgroup. Undetectable PSA at 24 wk was associated with longer OS, with a hazard ratio of 0.49 (95% CI 0.37-0.65) in the darolutamide group, as well as longer times to CRPC and PSA progression, with similar findings in the disease volume subgroups.

CONCLUSIONS AND CLINICAL IMPLICATIONS

Darolutamide + ADT + docetaxel led to deep and durable PSA responses in patients with high- or low-volume mHSPC. Achievement of undetectable PSA (<0.2 ng/ml) was correlated with better clinical outcomes.

PATIENT SUMMARY

For patients with metastatic hormone-sensitive prostate cancer being treated with androgen deprivation therapy and docetaxel, PSA (prostate-specific antigen) became undetectable (below 0.2 ng/ml) in 67% of those also receiving darolutamide versus 29% of patients also receiving placebo. On average, patients achieving undetectable PSA lived longer than patients with detectable PSA.

TROPHY-U-01, a phase II open-label study of sacituzumab govitecan in patients with metastatic urothelial carcinoma progressing after platinum-based chemotherapy and checkpoint inhibitors: updated safety and efficacy outcomes

BACKGROUND

Sacituzumab govitecan (SG) is a Trop-2-directed antibody-drug conjugate containing cytotoxic SN-38, the active metabolite of irinotecan. SG received accelerated US Food and Drug Administration approval for locally advanced (LA) or metastatic urothelial carcinoma (mUC) previously treated with platinum-based chemotherapy and a checkpoint inhibitor, based on cohort 1 of the TROPHY-U-01 study. Mutations in the uridine diphosphate glucuronosyltransferase 1A1 (UGT1A1) gene are associated with increased adverse events (AEs) with irinotecan-based therapies. Whether UGT1A1 status could impact SG toxicity and efficacy remains unclear.

PATIENTS AND METHODS

TROPHY-U-01 (NCT03547973) is a multicohort, open-label, phase II registrational study. Cohort 1 includes patients with LA or mUC who progressed after platinum- and checkpoint inhibitor-based therapies. SG was administered at 10 mg/kg intravenously on days 1 and 8 of 21-day cycles. The primary endpoint was objective response rate (ORR) per central review; secondary endpoints included progression-free survival, overall survival, and safety. Post hoc safety analyses were exploratory with descriptive statistics. Updated analyses include longer follow-up.

RESULTS

Cohort 1 included 113 patients. At a median follow-up of 10.5 months, ORR was 28% (95% CI 20.2% to 37.6%). Median progression-free survival and overall survival were 5.4 months (95% CI 3.5-6.9 months) and 10.9 months (95% CI 8.9-13.8 months), respectively. Occurrence of grade ≥3 treatment-related AEs and treatment-related discontinuation were consistent with prior reports. UGT1A1 status was wildtype (∗1|∗1) in 40%, heterozygous (∗1|∗28) in 42%, homozygous (∗28|∗28) in 12%, and missing in 6% of patients. In patients with ∗1|∗1, ∗1|∗28, and ∗28|∗28 genotypes, any grade treatment-related AEs occurred in 93%, 94%, and 100% of patients, respectively, and were managed similarly regardless of UGT1A1 status.

CONCLUSIONS

With longer follow-up, the ORR remains high in patients with heavily pretreated LA or mUC. Safety data were consistent with the known SG toxicity profile. AE incidence varied across UGT1A1 subgroups; however, discontinuation rates remained relatively low for all groups.

Efficacy and Safety of Darolutamide in Combination With Androgen-Deprivation Therapy and Docetaxel in Black Patients From the Randomized ARASENS Trial

BACKGROUND

In the ARASENS trial (NCT02799602), darolutamide in combination with androgen-deprivation therapy (ADT) and docetaxel significantly reduced the risk of death by 32.5% (HR, 0.68; 95% CI, 0.57-0.80; P < .0001) compared with placebo plus ADT with docetaxel in patients with metastatic hormone-sensitive prostate cancer (mHSPC). We present efficacy and safety of darolutamide versus placebo in Black patients from ARASENS.

PATIENTS AND METHODS

Patients with mHSPC were randomized 1:1 to darolutamide 600 mg or placebo twice daily in combination with ADT and docetaxel. The primary endpoint was overall survival. Key secondary endpoints included time to castration-resistant prostate cancer (CRPC) and safety.

RESULTS

In ARASENS, 54 Black patients received darolutamide (n = 26) or placebo (n = 28) plus ADT and docetaxel. In Black patients, overall survival favored darolutamide versus placebo (median, not reached vs. 38.7 months; stratified HR, 0.41; 95% CI, 0.17-1.02), with 4-year survival rates of 62% versus 41%. The darolutamide group also had longer time to CRPC compared with the placebo group (median, not reached vs .12.6 months; HR, 0.09; 95% CI, 0.02-0.30). The safety profile of darolutamide in Black patients was consistent with that observed for the overall ARASENS population (grade 3/4 treatment-emergent adverse events, TEAEs: 61.5% vs. 66.1%; serious TEAEs: 42.3% vs. 44.8%).

CONCLUSION

In this small population of Black patients with mHSPC from the ARASENS trial, darolutamide was associated with an improvement in survival and time to CRPC and was well tolerated. Efficacy and safety findings in Black patients were consistent with the overall ARASENS population.

Prostate-Specific Membrane Antigen-Targeting Alpha Emitter via Antibody Delivery for Metastatic Castration-Resistant Prostate Cancer: A Phase I Dose-Escalation Study of 225Ac-J591

PURPOSE

Novel therapies are needed to extend survival in metastatic castration-resistant prostate cancer (mCRPC). Prostate-specific membrane antigen (PSMA), a cell surface antigen overexpressed in PC, provides a validated target. This dose-escalation study investigated the safety, efficacy, maximum tolerated dose (MTD), and recommended phase II dose (RP2D) for 225Ac-J591, anti-PSMA monoclonal antibody J591 radiolabeled with the alpha emitter actinium-225.

METHODS

Following investigational new drug-enabling preclinical studies, we enrolled patients with progressive mCRPC that was refractory to or who refused standard treatment options (including androgen receptor pathway inhibitor and had received or been deemed ineligible for taxane chemotherapy). No selection for PSMA was performed. Patients received a single dose of 225Ac-J591 at one of seven dose-escalation levels followed by expansion at the highest dose. Primary end point of dose-escalation cohort was determination of dose-limiting toxicity (DLT) and RP2D.

RESULTS

Radiochemistry and animal studies were favorable. Thirty-two patients received 225Ac-J591 in an accelerated dose-escalation design (22 in dose escalation, 10 in expansion). One patient (1 of 22; 4.5%) experienced DLT in cohort 6 (80 KBq/kg) but none in cohort 7; MTD was not reached, and RP2D was the highest dose level (93.3 KBq/kg). The majority of high-grade adverse events (AEs) were hematologic with an apparent relationship with administered radioactivity. Nonhematologic AEs were generally of low grade. Prostate-specific antigen (PSA) declines and circulating tumor cell (CTC) control were observed: 46.9% had at least 50% PSA decline at any time (34.4% confirmed PSA response), and protocol-defined CTC count response occurred in 13 of 22 (59.1%).

CONCLUSION

To our knowledge, this is the first-in-human phase I dose-escalation trial of a single dose of 225Ac-J591 in 32 patients with pretreated progressive mCRPC demonstrated safety and preliminary efficacy signals. Further investigation is underway.

Avelumab First-line Maintenance for Advanced Urothelial Carcinoma: Analysis from JAVELIN Bladder 100 by Duration of First-line Chemotherapy and Interval Before Maintenance

BACKGROUND

In the JAVELIN Bladder 100 phase 3 trial, avelumab first-line maintenance + best supportive care (BSC) prolonged overall survival (OS) and progression-free survival (PFS) versus BSC alone in patients with advanced urothelial carcinoma (advanced UC) without progression after first-line platinum-based chemotherapy.

OBJECTIVE

To report post hoc analyses of subgroups defined by the duration of first-line chemotherapy and interval before maintenance.

DESIGN, SETTING, AND PARTICIPANTS

Patients with advanced UC without progression after four to six cycles of platinum-based chemotherapy and a 4-10-wk interval after chemotherapy (n = 700) were randomized to receive avelumab + BSC or BSC alone. Subgroups were defined by duration (quartile [Q]) and estimated number of cycles of chemotherapy, and interval between chemotherapy and maintenance. The median follow-up was >19 mo in both arms.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

OS (primary endpoint), PFS, and safety were assessed.

RESULTS AND LIMITATIONS

Hazard ratios (95% confidence interval) for OS with avelumab + BSC versus BSC alone were as follows: by chemotherapy duration-Q3: 0.63 (0.39-1.00); by number of cycles-four cycles: 0.69 (0.48-1.00), five cycles: 0.98 (0.57-1.71), and six cycles: 0.66 (0.47-0.92); and by interval-4-<6 wk: 0.75 (0.54-1.04), 6-<8 wk: 0.67 (0.43-1.06), and 8-10 wk: 0.69 (0.47-1.02). Results were similar for PFS. Safety was similar across subgroups. All analyses were exploratory.

CONCLUSIONS

Post hoc analyses of OS and PFS in subgroups defined by first-line chemotherapy duration and interval before maintenance were generally consistent with the results in the overall population, with similar safety findings. Prospective trials are warranted to confirm these findings.

PATIENT SUMMARY

Avelumab maintenance treatment helped patients with advanced urothelial cancer without disease progression after at least four cycles of prior chemotherapy, and who started maintenance treatment at least 4 wk after chemotherapy, to live longer.

Deciphering the origin and therapeutic targets of cancer of unknown primary: a case report that illustrates the power of integrative whole-exome and transcriptome sequencing analysis

Cancer of unknown primary (CUP) represents a significant diagnostic and therapeutic challenge, being the third to fourth leading cause of cancer death, despite advances in diagnostic tools. This article presents a successful approach using a novel genomic analysis in the evaluation and treatment of a CUP patient, leveraging whole-exome sequencing (WES) and RNA sequencing (RNA-seq). The patient, with a history of multiple primary tumors including urothelial cancer, exhibited a history of rapid progression on empirical chemotherapy. The application of our approach identified a molecular target, characterized the tumor expression profile and the tumor microenvironment, and analyzed the origin of the tumor, leading to a tailored treatment. This resulted in a substantial radiological response across all metastatic sites and the predicted primary site of the tumor. We argue that a comprehensive genomic and molecular profiling approach, like the BostonGene© Tumor Portrait, can provide a more definitive, personalized treatment strategy, overcoming the limitations of current predictive assays. This approach offers a potential solution to an unmet clinical need for a standardized approach in identifying the tumor origin for the effective management of CUP.

Avelumab first-line maintenance treatment for advanced urothelial carcinoma: review of evidence to guide clinical practice

The JAVELIN Bladder 100 phase III trial led to the incorporation of avelumab first-line (1L) maintenance treatment into international guidelines as a standard of care for patients with advanced urothelial carcinoma (UC) without progression after 1L platinum-based chemotherapy. JAVELIN Bladder 100 showed that avelumab 1L maintenance significantly prolonged overall survival (OS) and progression-free survival in this population compared with a 'watch-and-wait' approach. The aim of this manuscript is to review clinical studies of avelumab 1L maintenance in patients with advanced UC, including long-term efficacy and safety data from JAVELIN Bladder 100, subgroup analyses in clinically relevant subpopulations, and 'real-world' data obtained outside of clinical trials, providing a comprehensive resource to support patient management. Extended follow-up from JAVELIN Bladder 100 has shown that avelumab provides a long-term efficacy benefit, with a median OS of 23.8 months measured from start of maintenance treatment, and 29.7 months measured from start of 1L chemotherapy. Longer OS was observed across subgroups, including patients who received 1L cisplatin + gemcitabine, patients who received four or six cycles of 1L chemotherapy, and patients with complete response, partial response, or stable disease as best response to 1L induction chemotherapy. No new safety signals were seen in patients who received ≥1 year of avelumab treatment, and toxicity was similar in those who had received cisplatin or carboplatin with gemcitabine. Other clinical datasets, including noninterventional studies conducted in Europe, USA, and Asia, have confirmed the efficacy of avelumab 1L maintenance. Potential subsequent treatment options after avelumab maintenance include antibody-drug conjugates (enfortumab vedotin or sacituzumab govitecan), erdafitinib in biomarker-selected patients, platinum rechallenge in suitable patients, nonplatinum chemotherapy, and clinical trial participation; however, evidence to determine optimal treatment sequences is needed. Ongoing trials of avelumab-based combination regimens as maintenance treatment have the potential to evolve the treatment landscape for patients with advanced UC.

The importance of escalating molecular diagnostics in patients with low-grade pediatric brain cancer

Pilocytic astrocytomas are the most common pediatric brain tumors, typically presenting as low-grade neoplasms. We report two cases of pilocytic astrocytoma with atypical tumor progression. Case 1 involves a 12-yr-old boy with an unresectable suprasellar tumor, negative for BRAF rearrangement but harboring a BRAF p.V600E mutation. He experienced tumor size reduction and stable disease following dabrafenib treatment. Case 2 describes a 6-yr-old boy with a thalamic tumor that underwent multiple resections, with no actionable driver detected using targeted next-generation sequencing. Whole-genome and RNA-seq analysis identified an internal tandem duplication in FGFR1 and RAS pathway activation. Future management options include FGFR1 inhibitors. These cases demonstrate the importance of escalating molecular diagnostics for pediatric brain cancer, advocating for early reflexing to integrative whole-genome sequencing and transcriptomic profiling when targeted panels are uninformative. Identifying molecular drivers can significantly impact treatment decisions and improve patient outcomes.

Outcomes of relapsed clinical stage I versus de novo metastatic testicular cancer patients: an analysis of the IGCCCG Update database

BACKGROUND

Active surveillance after orchiectomy is the preferred management in clinical stage I (CSI) germ-cell tumours (GCT) associated with a 15 to 30% relapse rate.

PATIENTS AND METHODS

In the IGCCCG Update database, we compared the outcomes of gonadal disseminated GCT relapsing from initial CSI to outcomes of patients with de novo metastatic GCT.

RESULTS

A total of 1014 seminoma (Sem) [298 (29.4%) relapsed from CSI, 716 (70.6%) de novo] and 3103 non-seminoma (NSem) [626 (20.2%) relapsed from CSI, 2477 (79.8%) de novo] were identified. Among Sem, no statistically significant differences in PFS and OS were found between patients relapsing from CSI and de novo metastatic disease [5-year progression-free survival (5y-PFS) 87.6% versus 88.5%; 5-year overall survival (5y-OS) 93.2% versus 96.1%). Among NSem, PFS and OS were higher overall in relapsing CSI patients (5y-PFS 84.6% versus 80.0%; 5y-OS 93.3% versus 88.7%), but there were no differences within the same IGCCCG prognostic groups (HR = 0.89; 95% CI: 0.70-1.12). Relapses in the intermediate or poor prognostic groups occurred in 11/298 (4%) Sem and 112/626 (18%) NSem.

CONCLUSION

Relapsing CSI GCT patients expect similar survival compared to de novo metastatic patients of the same ICCCCG prognostic group. Intermediate and poor prognosis relapses from initial CSI expose patients to unnecessary toxicity from more intensive treatments.

Prognostic value of neutrophil-to-lymphocyte ratio in patients with metastatic castration-resistant prostate cancer receiving prostate-specific membrane antigen targeted radionuclide therapy

BACKGROUND

Neutrophil count:lymphocyte count ratio (NLR) may be a prognostic factor for men with advanced prostate cancer. We hypothesized that it is associated with prostate-specific antigen (PSA) response and survival in men treated with prostate-specific membrane antigen (PSMA)-targeted radionuclide therapy (TRT).

METHODS

Data of 180 men with metastatic castration-resistant prostate cancer (mCRPC) who were treated in sequential prospective radionuclide clinical trials from 2002 to 2021 (utilizing 177Lu-J591, 90Y-J591, 177Lu-PSMA-617, or 225Ac-J591) were retrospectively analyzed. We used a logistic regression to determine the association between NLR and ≥50% PSA decline (PSA50) and a Cox proportional hazards model to investigate the association between NLR and overall survival (OS).

RESULTS

A total of 94 subjects (52.2%) received 177Lu-J591, 51 (28.3%) 177Lu-PSMA-617, 28 (15.6%) 225Ac-J591, and 7 (3.9%) 90Y-J591. The median NLR of 3.75 was used as cut-off (low vs. high NLR; n = 90, respectively). On univariate analysis, NLR was not associated with PSA50 (HR 1.08; 95% confidence interval [CI] 0.99-1.17, p = 0.067). However, it was associated with worse OS (hazard ratio [HR] 1.06, 95% CI 1.02-1.09, p = 0.002), also after controlling for circulating tumor cell count and cancer and leukemia group B risk group (HR 1.05; 95% CI 1.003-1.11, p = 0.036). Men with high NLR were at a higher hazard of death from all causes (HR 1.43, 95% CI 1.05-1.94, p = 0.024).

CONCLUSIONS

NLR provides prognostic information in the setting of patients with mCRPC receiving treatment with PSMA-TRT.

Plain language summary: Can declines in prostate-specific antigen level indicate how long patients with advanced prostate cancer will live when treated with enzalutamide?

WHAT IS THIS SUMMARY ABOUT?

This is a summary of a research article originally published in the Journal of Urology. The PROSPER study involved men who had a type of advanced prostate cancer called non-metastatic castration-resistant prostate cancer (nmCRPC). In patients with nmCRPC, their prostate cancer keeps growing even after traditional hormone treatments. In these patients, rising prostate-specific antigen (PSA) levels suggest that cancer is active but CT and bone scans show that it has not spread to other parts of the body. Everyone in this study received androgen deprivation therapy (ADT) either with the medicine enzalutamide or a placebo. Enzalutamide is a medicine that can slow or stop androgens, such as testosterone, from making prostate cancer grow. The main results of the PROSPER study showed that patients with nmCRPC treated with enzalutamide and ADT lived longer than patients treated with placebo and ADT. In this study, researchers wanted to know if the findings were different depending on how much patients' PSA level declined after enzalutamide treatment. Researchers also wanted to know if this made a difference in how long patients lived without the cancer spreading to other parts of their body.

WHAT WERE THE RESULTS?

Researchers found that patients with a large decline in PSA level after treatment were more likely to live longer and without their cancer spreading.

WHAT DO THE RESULTS MEAN?

This study shows a link between PSA level changes and how long patients with nmCRPC live when treated with enzalutamide and ADT. These results may help health professionals monitor patients with different PSA level changes after enzalutamide treatment. Patients with a large decline in PSA level may not need to be monitored as closely as patients with a small decline in PSA level.

Randomized phase II trial of MRI-guided salvage radiotherapy for prostate cancer in 4 weeks versus 2 weeks (SHORTER)

BACKGROUND

Ultra-hypofractionated image-guided stereotactic body radiotherapy (SBRT) is increasingly used for definitive treatment of localized prostate cancer. Magnetic resonance imaging-guided radiotherapy (MRgRT) facilitates improved visualization, real-time tracking of targets and/or organs-at-risk (OAR), and capacity for adaptive planning which may translate to improved targeting and reduced toxicity to surrounding tissues. Given promising results from NRG-GU003 comparing conventional and moderate hypofractionation in the post-operative setting, there is growing interest in exploring ultra-hypofractionated post-operative regimens. It remains unclear whether this can be done safely and whether MRgRT may help mitigate potential toxicity. SHORTER (NCT04422132) is a phase II randomized trial prospectively evaluating whether salvage MRgRT delivered in 5 fractions versus 20 fractions is non-inferior with respect to gastrointestinal (GI) and genitourinary (GU) toxicities at 2-years post-treatment.

METHODS

A total of 136 patients will be randomized in a 1:1 ratio to salvage MRgRT in 5 fractions or 20 fractions using permuted block randomization. Patients will be stratified according to baseline Expanded Prostate Cancer Index Composite (EPIC) bowel and urinary domain scores as well as nodal treatment and androgen deprivation therapy (ADT). Patients undergoing 5 fractions will receive a total of 32.5 Gy over 2 weeks and patients undergoing 20 fractions will receive a total of 55 Gy over 4 weeks, with or without nodal coverage (25.5 Gy over 2 weeks and 42 Gy over 4 weeks) and ADT as per the investigator's discretion. The co-primary endpoints are change scores in the bowel and the urinary domains of the EPIC. The change scores will reflect the 2-year score minus the pre-treatment (baseline) score. The secondary endpoints include safety endpoints, including change in GI and GU symptoms at 3, 6, 12 and 60 months from completion of treatment, and efficacy endpoints, including time to progression, prostate cancer specific survival and overall survival.

DISCUSSION

The SHORTER trial is the first randomized phase II trial comparing toxicity of ultra-hypofractionated and hypofractionated MRgRT in the salvage setting. The primary hypothesis is that salvage MRgRT delivered in 5 fractions will not significantly increase GI and GU toxicities when compared to salvage MRgRT delivered in 20 fractions.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT04422132. Date of registration: June 9, 2020.

Darolutamide Plus Androgen-Deprivation Therapy and Docetaxel in Metastatic Hormone-Sensitive Prostate Cancer by Disease Volume and Risk Subgroups in the Phase III ARASENS Trial

PURPOSE

For patients with metastatic hormone-sensitive prostate cancer, metastatic burden affects outcome. We examined efficacy and safety from the ARASENS trial for subgroups by disease volume and risk.

METHODS

Patients with metastatic hormone-sensitive prostate cancer were randomly assigned to darolutamide or placebo plus androgen-deprivation therapy and docetaxel. High-volume disease was defined as visceral metastases and/or ≥ 4 bone metastases with ≥ 1 beyond the vertebral column/pelvis. High-risk disease was defined as ≥ 2 risk factors: Gleason score ≥ 8, ≥ 3 bone lesions, and presence of measurable visceral metastases.

RESULTS

Of 1,305 patients, 1,005 (77%) had high-volume disease and 912 (70%) had high-risk disease. Darolutamide increased overall survival (OS) versus placebo in patients with high-volume (hazard ratio [HR], 0.69; 95% CI, 0.57 to 0.82), high-risk (HR, 0.71; 95% CI, 0.58 to 0.86), and low-risk disease (HR, 0.62; 95% CI, 0.42 to 0.90), and in the smaller low-volume subgroup, the results were also suggestive of survival benefit (HR, 0.68; 95% CI, 0.41 to 1.13). Darolutamide improved clinically relevant secondary end points of time to castration-resistant prostate cancer and subsequent systemic antineoplastic therapy versus placebo in all disease volume and risk subgroups. Adverse events (AEs) were similar between treatment groups across subgroups. Grade 3 or 4 AEs occurred in 64.9% of darolutamide patients versus 64.2% of placebo patients in the high-volume subgroup and 70.1% versus 61.1% in the low-volume subgroup. Among the most common AEs, many were known toxicities related to docetaxel.

CONCLUSION

In patients with high-volume and high-risk/low-risk metastatic hormone-sensitive prostate cancer, treatment intensification with darolutamide, androgen-deprivation therapy, and docetaxel increased OS with a similar AE profile in the subgroups, consistent with the overall population.[Media: see text].

Avelumab First-line Maintenance Therapy for Advanced Urothelial Carcinoma: Comprehensive Clinical Subgroup Analyses from the JAVELIN Bladder 100 Phase 3 Trial

BACKGROUND

In the phase 3 JAVELIN Bladder 100 trial, avelumab first-line (1L) maintenance + best supportive care (BSC) significantly prolonged overall survival (OS) and progression-free survival (PFS) versus BSC alone in patients with advanced urothelial carcinoma (aUC) who were progression-free following 1L platinum-based chemotherapy, leading to regulatory approval in various countries.

OBJECTIVE

To analyze clinically relevant subgroups from JAVELIN Bladder 100.

DESIGN, SETTING, AND PARTICIPANTS

Patients with unresectable locally advanced or metastatic UC without progression on 1L gemcitabine + cisplatin or carboplatin were randomized to receive avelumab + BSC (n = 350) or BSC alone (n = 350). Median follow-up was >19 mo in both arms (data cutoff October 21, 2019). This trial is registered on ClinicalTrials.gov as NCT02603432.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

OS (primary endpoint) and PFS were analyzed in protocol-specified and post hoc subgroups using the Kaplan-Meier method and Cox proportional hazards models.

RESULTS AND LIMITATIONS

Hazard ratios (HRs) for OS with avelumab + BSC versus BSC alone were <1.0 across all subgroups examined, including patients treated with 1L cisplatin + gemcitabine (HR 0.69, 95% confidence interval [CI] 0.50-0.93) or carboplatin + gemcitabine (HR 0.64, 95% CI 0.46-0.90), patients with PD-L1+ tumors treated with carboplatin + gemcitabine (HR 0.67, 95% CI 0.39-1.14), and patients whose best response to chemotherapy was a complete response (HR 0.80, 95% CI 0.46-1.37), partial response (HR 0.62, 95% CI 0.46-0.84), or stable disease (HR 0.70, 95% CI 0.46-1.06). Observations were similar for PFS. Limitations include the smaller size and post hoc evaluation without multiplicity adjustment for some subgroups.

CONCLUSIONS

Analyses of OS and PFS in clinically relevant subgroups were consistent with results for the overall population, further supporting avelumab 1L maintenance as standard-of-care treatment for patients with aUC who are progression-free following 1L platinum-based chemotherapy.

PATIENT SUMMARY

In the JAVELIN Bladder 100 study, maintenance treatment with avelumab helped many different groups of people with advanced cancer of the urinary tract to live longer.

Clinical outcomes and treatment patterns in REASSURE: planned interim analysis of a real-world observational study of radium-223 in metastatic castration-resistant prostate cancer

Background

Radium-223, a targeted alpha therapy, is approved to treat bone-dominant metastatic castration-resistant prostate cancer (mCRPC), based on significantly prolonged overall survival versus placebo and a favourable safety profile in the phase 3 ALSYMPCA study. ALSYMPCA was conducted when few other treatment options were available, and prospectively collected data are limited on the use of radium-223 in the current mCRPC treatment landscape. We sought to understand long-term safety and treatment patterns in men who received radium-223 in real-world clinical practice.

Methods

REASSURE (NCT02141438) is a global, prospective, observational study of radium-223 in men with mCRPC. Primary outcomes are adverse events (AEs), including treatment-emergent serious AEs (SAEs) and drug-related AEs during and ≤30 days after radium-223 completion, grade 3/4 haematological toxicities ≤6 months after last radium-223 dose, drug-related SAEs after radium-223 therapy completion, and second primary malignancies.

Findings

Data collection commenced on Aug 20, 2014, and the data cutoff date for this prespecified interim analysis was Mar 20, 2019 (median follow-up 11.5 months [interquartile range 6.0-18.6]), 1465 patients were evaluable. For second primary malignancies, 1470 patients were evaluable, 21 (1%) of whom had a total of 23 events. During radium-223 therapy, 311 (21%) of 1465 patients had treatment-emergent SAEs, and 510 (35%) had drug-related AEs. In the 6 months after completion of radium-223 therapy, 214 (15%) patients had grade 3/4 haematological toxicities. Eighty patients (5%) had post-treatment drug-related SAEs. Median overall survival was 15.6 months (95% confidence interval 14.6-16.5) from radium-223 initiation. Patient-reported pain scores declined or stabilised. Seventy (5%) patients had fractures.

Interpretation

REASSURE offers insight into radium-223 use in global real-world clinical practice with currently available therapies. At this interim analysis, with a median follow-up of almost 1 year, 1% of patients had second primary malignancies, and safety and overall survival findings were consistent with clinical trial experience. Final analysis of REASSURE is due in 2024.

Funding

Bayer HealthCare.

External Validation of a Prognostic Model of Overall Survival in Men With Chemotherapy-Naïve Metastatic Castration-Resistant Prostate Cancer

PURPOSE

We have previously developed and externally validated a prognostic model of overall survival (OS) in men with metastatic, castration-resistant prostate cancer (mCRPC) treated with docetaxel. We sought to externally validate this model in a broader group of men with docetaxel-naïve mCRPC and in specific subgroups (White, Black, Asian patients, different age groups, and specific treatments) and to classify patients into validated two and three prognostic risk groupings on the basis of the model.

METHODS

Data from 8,083 docetaxel-naïve mCRPC men randomly assigned on seven phase III trials were used to validate the prognostic model of OS. We assessed the predictive performance of the model by computing the time-dependent area under the receiver operating characteristic curve (tAUC) and validated the two-risk (low and high) and three-risk prognostic groups (low, intermediate, and high).

RESULTS

The tAUC was 0.74 (95% CI, 0.73 to 0.75), and when adjusting for the first-line androgen receptor (AR) inhibitor trial status, the tAUC was 0.75 (95% CI, 0.74 to 0.76). Similar results were observed by the different racial, age, and treatment subgroups. In patients enrolled on first-line AR inhibitor trials, the median OS (months) in the low-, intermediate-, and high-prognostic risk groups were 43.3 (95% CI, 40.7 to 45.8), 27.7 (95% CI, 25.8 to 31.3), and 15.4 (95% CI, 14.0 to 17.9), respectively. Compared with the low-risk prognostic group, the hazard ratios for the high- and intermediate-risk groups were 4.3 (95% CI, 3.6 to 5.1; P < .0001) and 1.9 (95% CI, 1.7 to 2.1; P < .0001).

CONCLUSION

This prognostic model for OS in docetaxel-naïve men with mCRPC has been validated using data from seven trials and yields similar results overall and across race, age, and different treatment classes. The prognostic risk groups are robust and can be used to identify groups of patients for enrichment designs and for stratification in randomized clinical trials.

Management of patients with advanced prostate cancer-metastatic and/or castration-resistant prostate cancer: Report of the Advanced Prostate Cancer Consensus Conference (APCCC) 2022

BACKGROUND

Innovations in imaging and molecular characterisation together with novel treatment options have improved outcomes in advanced prostate cancer. However, we still lack high-level evidence in many areas relevant to making management decisions in daily clinical practise. The 2022 Advanced Prostate Cancer Consensus Conference (APCCC 2022) addressed some questions in these areas to supplement guidelines that mostly are based on level 1 evidence.

OBJECTIVE

To present the voting results of the APCCC 2022.

DESIGN, SETTING, AND PARTICIPANTS

The experts voted on controversial questions where high-level evidence is mostly lacking: locally advanced prostate cancer; biochemical recurrence after local treatment; metastatic hormone-sensitive, non-metastatic, and metastatic castration-resistant prostate cancer; oligometastatic prostate cancer; and managing side effects of hormonal therapy. A panel of 105 international prostate cancer experts voted on the consensus questions.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The panel voted on 198 pre-defined questions, which were developed by 117 voting and non-voting panel members prior to the conference following a modified Delphi process. A total of 116 questions on metastatic and/or castration-resistant prostate cancer are discussed in this manuscript. In 2022, the voting was done by a web-based survey because of COVID-19 restrictions.

RESULTS AND LIMITATIONS

The voting reflects the expert opinion of these panellists and did not incorporate a standard literature review or formal meta-analysis. The answer options for the consensus questions received varying degrees of support from panellists, as reflected in this article and the detailed voting results are reported in the supplementary material. We report here on topics in metastatic, hormone-sensitive prostate cancer (mHSPC), non-metastatic, castration-resistant prostate cancer (nmCRPC), metastatic castration-resistant prostate cancer (mCRPC), and oligometastatic and oligoprogressive prostate cancer.

CONCLUSIONS

These voting results in four specific areas from a panel of experts in advanced prostate cancer can help clinicians and patients navigate controversial areas of management for which high-level evidence is scant or conflicting and can help research funders and policy makers identify information gaps and consider what areas to explore further. However, diagnostic and treatment decisions always have to be individualised based on patient characteristics, including the extent and location of disease, prior treatment(s), co-morbidities, patient preferences, and treatment recommendations and should also incorporate current and emerging clinical evidence and logistic and economic factors. Enrolment in clinical trials is strongly encouraged. Importantly, APCCC 2022 once again identified important gaps where there is non-consensus and that merit evaluation in specifically designed trials.

PATIENT SUMMARY

The Advanced Prostate Cancer Consensus Conference (APCCC) provides a forum to discuss and debate current diagnostic and treatment options for patients with advanced prostate cancer. The conference aims to share the knowledge of international experts in prostate cancer with healthcare providers worldwide. At each APCCC, an expert panel votes on pre-defined questions that target the most clinically relevant areas of advanced prostate cancer treatment for which there are gaps in knowledge. The results of the voting provide a practical guide to help clinicians discuss therapeutic options with patients and their relatives as part of shared and multidisciplinary decision-making. This report focuses on the advanced setting, covering metastatic hormone-sensitive prostate cancer and both non-metastatic and metastatic castration-resistant prostate cancer.

TWITTER SUMMARY

Report of the results of APCCC 2022 for the following topics: mHSPC, nmCRPC, mCRPC, and oligometastatic prostate cancer.

TAKE-HOME MESSAGE

At APCCC 2022, clinically important questions in the management of advanced prostate cancer management were identified and discussed, and experts voted on pre-defined consensus questions. The report of the results for metastatic and/or castration-resistant prostate cancer is summarised here.

Avelumab First-Line Maintenance for Advanced Urothelial Carcinoma: Results From the JAVELIN Bladder 100 Trial After ≥2 Years of Follow-Up

Clinical trials frequently include multiple end points that mature at different times. The initial report, typically based on the primary end point, may be published when key planned coprimary or secondary analyses are not yet available. Clinical trial updates provide an opportunity to disseminate additional results from studies, published in JCO or elsewhere, for which the primary end point has already been reported.Initial results from the phase III JAVELIN Bladder 100 trial (ClinicalTrials.gov identifier: NCT02603432) showed that avelumab first-line (1L) maintenance plus best supportive care (BSC) significantly prolonged overall survival (OS) and progression-free survival (PFS) versus BSC alone in patients with advanced urothelial carcinoma (aUC) who were progression-free after 1L platinum-containing chemotherapy. Avelumab 1L maintenance treatment is now a standard of care for aUC. Here, we report updated data with ≥ 2 years of follow-up in all patients, including OS (primary end point), PFS, safety, and additional novel analyses. Patients were randomly assigned 1:1 to receive avelumab plus BSC (n = 350) or BSC alone (n = 350). At data cutoff (June 4, 2021), median follow-up was 38.0 months and 39.6 months, respectively; 67 patients (19.5%) had received ≥2 years of avelumab treatment. OS remained longer with avelumab plus BSC versus BSC alone in all patients (hazard ratio, 0.76 [95% CI, 0.63 to 0.91]; 2-sided P = .0036). Investigator-assessed PFS analyses also favored avelumab. Longer-term safety was consistent with previous analyses; no new safety signals were identified with longer treatment duration. In conclusion, longer-term follow-up continues to show clinically meaningful efficacy benefits with avelumab 1L maintenance plus BSC versus BSC alone in patients with aUC. An interactive visualization of data reported in this article is available.

Pazopanib in Locally Advanced or Metastatic Renal Cell Carcinoma: Results of a Randomized Phase III Trial

PURPOSE

Pazopanib is an oral angiogenesis inhibitor targeting vascular endothelial growth factor receptor, platelet-derived growth factor receptor, and c-Kit. This randomized, double-blind, placebo-controlled phase III study evaluated efficacy and safety of pazopanib monotherapy in treatment-naive and cytokine-pretreated patients with advanced renal cell carcinoma (RCC).

PATIENTS AND METHODS

Adult patients with measurable, locally advanced, and/or metastatic RCC were randomly assigned 2:1 to receive oral pazopanib or placebo. The primary end point was progression-free survival (PFS). Secondary end points included overall survival, tumor response rate (Response Evaluation Criteria in Solid Tumors), and safety. Radiographic assessments of tumors were independently reviewed.

RESULTS

Of 435 patients enrolled, 233 were treatment naive (54%) and 202 were cytokine pretreated (46%). PFS was significantly prolonged with pazopanib compared with placebo in the overall study population (median, PFS 9.2 v 4.2 months; hazard ratio [HR], 0.46; 95% CI, 0.34 to 0.62; P < .0001), the treatment-naive subpopulation (median PFS 11.1 v 2.8 months; HR, 0.40; 95% CI, 0.27 to 0.60; P < .0001), and the cytokine-pretreated subpopulation (median PFS, 7.4 v 4.2 months; HR, 0.54; 95% CI, 0.35 to 0.84; P < .001). The objective response rate was 30% with pazopanib compared with 3% with placebo (P < .001). The median duration of response was longer than 1 year. The most common adverse events were diarrhea, hypertension, hair color changes, nausea, anorexia, and vomiting. There was no evidence of clinically important differences in quality of life for pazopanib versus placebo.

CONCLUSION

Pazopanib demonstrated significant improvement in PFS and tumor response compared with placebo in treatment-naive and cytokine-pretreated patients with advanced and/or metastatic RCC.

Abstract NG10: Chromatin profiles classify castration-resistant prostate cancers suggesting therapeutic targets

Untreated prostate cancers rely on androgen receptor (AR) signaling for growth and survival, forming the basis for the initial efficacy of androgen deprivation therapy (ADT). Yet the disease can relapse and progress to a lethal stage termed castration-resistant prostate cancer (CRPC). Reactivation of AR signaling represents the most common driver of CRPC growth, and next-generation AR signaling inhibitors (ARSIs) are now used in combination with ADT as first-line therapy. However, ARSIs can result in selective pressure, thereby generating AR-independent tumors. The transition from AR dependence frequently accompanies a change in a phenotype resembling developmental transdifferentiation or “lineage plasticity”. Neuroendocrine prostate cancer, which lacks a defined pathologic classification, is the most studied type of lineage plasticity. However, most AR-null tumors do not exhibit neuroendocrine features and are classified as “double-negative prostate cancer”, the drivers of which are poorly defined. Lineage plasticity studies in CRPC are limited by the lack of genetically defined patient-derived models that recapitulate the disease spectrum. To address this, we developed a biobank of organoids generated from patient biopsies to study the landscape of metastatic CRPC and allow for functional validation assays. Proteins called transcription factors (TFs) are drivers of tumor lineage plasticity. To identify the key TFs that drive the growth of AR-independent tumors, we integrated epigenetic and transcriptomic data generated from CRPC models. We generated ATAC-seq (assay for transposase-accessible chromatin sequencing) and RNA-seq data from 22 metastatic human prostate cancer organoids, six patient-derived xenografts (PDXs), and 12 derived or traditional cell lines. We classified the 40 models into four subtypes and predicted key TFs of each subtype. Besides the well-characterized AR-dependent (CRPC-AR) and neuroendocrine subtypes (CRPC-NE), we identified two novel AR-negative/low groups, including a Wnt-dependent subtype (CRPC-WNT), driven by TCF/LEF TFs, and a stem cell-like (SCL) subtype (CRPC-SCL), driven by the AP-1 family of TFs. To apply the subtype classification to patient samples, we derived RNA-seq signatures from the organoids and applied them to 366 patient samples from two independent CRPC cohorts. The generated signatures recapitulated the four-subtype classification and revealed that CRPC-SCL is the second most prevalent group. Patients from CRPC-SCL are also associated with shorter time under ARSI treatment compared to CRPC-AR, indicating that the ARSI treatments were less effective for CRPC-SCL patients. Additional chromatin immunoprecipitation sequencing (ChIP-seq) analysis indicated that AP-1 (FOSL1) collaboratively binds with TEAD and transcription coactivators, YAP and TAZ. Knocking down of AP-1 (FOSL1), YAP/TAZ decreased cell growth of CRPC-SCL and showed a decrease of chromatin accessibility at CRPC-SCL-specific open chromatin sites and down-regulation of YAP/TAZ target gene expression. In addition, the expression of AP-1 (FOSL1) decreased upon YAP/TAZ knockdown suggesting a positive feedback loop as well as YAP/TAZ as actional targets in CRPC-SCL. We used two small-molecule inhibitors, verteporfin and T-5224, that act on the YAP/TAZ/AP-1 pathway for their potential use as therapeutics for CRPC-SCL tumors, both inhibited the growth of samples from CRPC-SCL but not CRPC-AR. By overexpressing an AP-1 family gene (FOSL1) in AR-high cells, we observed an increase in chromatin accessibility at CRPC-SCL-specific open chromatin sites as well as significant up-regulation of CRPC-SCL signature genes, suggesting that AP-1 functions as a pioneering factor and master regulator for CRPC-SCL. All this work was recently published in Science (Tang, Xu et al. Science, 2022) where I am the co-first author. In summary, by using a diverse biobank of organoids, PDXs, and cell lines that recapitulate the heterogeneity of metastatic prostate cancer, we created a map of the chromatin accessibility and transcriptomic landscape of CRPC. We validated the CRPC-AR and CRPC-NE subtypes and report two novel subtypes of AR-negative/low samples, CRPC-SCL and CRPC-WNT, as well as their respective key TFs. Additional analysis revealed a model in which YAP, TAZ, TEAD, and AP-1 function together and drive oncogenic growth in CRPC-SCL samples. In addition, we proposed small inhibitors of YAP and TAZ that can potentially be used to treat CRPC-SCL patients. Overall, our results show how the stratification of CRPC patients into four subtypes using their transcriptomes can potentially inform appropriate clinical decisions.

Citation Format: Fanying Tang, Duo Xu, Shangqian Wang, Chen Khuan Wong, Alexander Martinez-Fundichely, Cindy J. Lee, Sandra Cohen, Jane Park, Corinne E. Hill, Kenneth Eng, Rohan Bareja, Teng Han, Eric Minwei Liu, Ann Palladino, Wei Di, Dong Gao, Wassim Abida, Shaham Beg, Loredana Puca, Maximiliano Meneses, Elisa de Stanchina, Michael F. Berger, Anuradha Gopalan, Lukas E. Dow, Juan Miguel Mosquera, Himisha Beltran, Cora N. Sternberg, Ping Chi, Howard I. Scher, Andrea Sboner, Yu Chen, Ekta Khurana. Chromatin profiles classify castration-resistant prostate cancers suggesting therapeutic targets. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr NG10.

Management of Patients with Advanced Prostate Cancer. Part I: Intermediate-/High-risk and Locally Advanced Disease, Biochemical Relapse, and Side Effects of Hormonal Treatment: Report of the Advanced Prostate Cancer Consensus Conference 2022

BACKGROUND

Innovations in imaging and molecular characterisation and the evolution of new therapies have improved outcomes in advanced prostate cancer. Nonetheless, we continue to lack high-level evidence on a variety of clinical topics that greatly impact daily practice. To supplement evidence-based guidelines, the 2022 Advanced Prostate Cancer Consensus Conference (APCCC 2022) surveyed experts about key dilemmas in clinical management.

OBJECTIVE

To present consensus voting results for select questions from APCCC 2022.

DESIGN, SETTING, AND PARTICIPANTS

Before the conference, a panel of 117 international prostate cancer experts used a modified Delphi process to develop 198 multiple-choice consensus questions on (1) intermediate- and high-risk and locally advanced prostate cancer, (2) biochemical recurrence after local treatment, (3) side effects from hormonal therapies, (4) metastatic hormone-sensitive prostate cancer, (5) nonmetastatic castration-resistant prostate cancer, (6) metastatic castration-resistant prostate cancer, and (7) oligometastatic and oligoprogressive prostate cancer. Before the conference, these questions were administered via a web-based survey to the 105 physician panel members ("panellists") who directly engage in prostate cancer treatment decision-making. Herein, we present results for the 82 questions on topics 1-3.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Consensus was defined as ≥75% agreement, with strong consensus defined as ≥90% agreement.

RESULTS AND LIMITATIONS

The voting results reveal varying degrees of consensus, as is discussed in this article and shown in the detailed results in the Supplementary material. The findings reflect the opinions of an international panel of experts and did not incorporate a formal literature review and meta-analysis.

CONCLUSIONS

These voting results by a panel of international experts in advanced prostate cancer can help physicians and patients navigate controversial areas of clinical management for which high-level evidence is scant or conflicting. The findings can also help funders and policymakers prioritise areas for future research. Diagnostic and treatment decisions should always be individualised based on patient and cancer characteristics (disease extent and location, treatment history, comorbidities, and patient preferences) and should incorporate current and emerging clinical evidence, therapeutic guidelines, and logistic and economic factors. Enrolment in clinical trials is always strongly encouraged. Importantly, APCCC 2022 once again identified important gaps (areas of nonconsensus) that merit evaluation in specifically designed trials.

PATIENT SUMMARY

The Advanced Prostate Cancer Consensus Conference (APCCC) provides a forum to discuss and debate current diagnostic and treatment options for patients with advanced prostate cancer. The conference aims to share the knowledge of international experts in prostate cancer with health care providers and patients worldwide. At each APCCC, a panel of physician experts vote in response to multiple-choice questions about their clinical opinions and approaches to managing advanced prostate cancer. This report presents voting results for the subset of questions pertaining to intermediate- and high-risk and locally advanced prostate cancer, biochemical relapse after definitive treatment, advanced (next-generation) imaging, and management of side effects caused by hormonal therapies. The results provide a practical guide to help clinicians and patients discuss treatment options as part of shared multidisciplinary decision-making. The findings may be especially useful when there is little or no high-level evidence to guide treatment decisions.

Harnessing transcriptionally driven chromosomal instability adaptation to target therapy-refractory lethal prostate cancer

Metastatic prostate cancer (PCa) inevitably acquires resistance to standard therapy preceding lethality. Here, we unveil a chromosomal instability (CIN) tolerance mechanism as a therapeutic vulnerability of therapy-refractory lethal PCa. Through genomic and transcriptomic analysis of patient datasets, we find that castration and chemotherapy-resistant tumors display the highest CIN and mitotic kinase levels. Functional genomics screening coupled with quantitative phosphoproteomics identify MASTL kinase as a survival vulnerability specific of chemotherapy-resistant PCa cells. Mechanistically, MASTL upregulation is driven by transcriptional rewiring mechanisms involving the non-canonical transcription factors androgen receptor splice variant 7 and E2F7 in a circuitry that restrains deleterious CIN and prevents cell death selectively in metastatic therapy-resistant PCa cells. Notably, MASTL pharmacological inhibition re-sensitizes tumors to standard therapy and improves survival of pre-clinical models. These results uncover a targetable mechanism promoting high CIN adaptation and survival of lethal PCa.

Randomized trial of five or two MRI-guided adaptive radiotherapy treatments for prostate cancer (FORT)

TPS399

Background: The objective of this randomized clinical trial is to demonstrate that 2 treatments of real-time MRI-guided radiotherapy (RT) does not significantly increase patient-reported GI and GU symptoms compared to 5 treatments of RT 2 years after treatment completion (24 months). Methods: Key Eligibility Criteria: Inclusion Criteria 1. Men aged > 18 with histologically confirmed low or intermediate risk prostate cancer per NCCN guidelines. 2. ECOG 0 – 1 3. IPSS < 18 4. Ability to receive MRI-guided radiotherapy. 5. Ability to complete the Expanded Prostate Cancer Index Composite (EPIC) questionnaire. Exclusion Criteria 1. Prior history of receiving pelvic RT. 2. Patient with history of IBD. 3. Hip replacements. 4. History of bladder neck or urethral stricture. 5. TURP < 8 weeks prior to RT 6. Metastatic (pelvic nodal or distant) disease on CT, Bone, and/or PSMA PET scan. Study Design/Endpoints: This is a randomized phase II non-inferiority trial comparing 2 fractions of ultrahypofractionated RT (25 Gy total with optional PSMA/MRI boost to 28 Gy) versus 5 fractions of ultra-hypofractionated RT (37.5 Gy total with optional PSMA/MRI boost to 45 Gy) in the definitive setting for prostate cancer. Subjects will be stratified based on pre-specified stratification factors and randomized 1:1 to receive 2 or 5 fractions using permuted block randomization. The primary endpoint is the change in patient-reported GI and GU symptoms as measured by EPIC at 2 years from end of treatment. Secondary endpoints will include both the safety endpoints including change in GI and GU symptoms at 3, 6, 12 and 60 months from end of treatment, and multiple efficacy endpoints including time to progression, prostate cancer specific survival and overall survival. Sample Size: The sample size is calculated based on a non-inferiority design. The non-inferiority margins are set to be a change score of 6 points for the GI symptoms and 5 points for the GU symptoms. The standard deviations of the change scores are assumed to be 13.2 for the GI symptoms and 10.5 for the GU symptoms based on estimates generated in RTOG 0415 trial. This level of change in scores are deemed as clinically meaningful. For example, 6 points of change score for GI symptoms corresponds to two symptoms worsening by 1 level (i.e., loose stools and frequency of bowel movements change from “no problem” to “very small problem”) or one of the symptoms worsening by 2 levels (i.e., loose stool change from “no problem” to “small problem”). A sample size of 122 with 61 in each arm will ensure 80% power for GI endpoint and 83% power for GU endpoint to detect non-inferiority using a one-sided two-sample t-test at the significance level of 0.05. Adjusting for a projected 10% EPIC/non-compliance rate, 136 patients (68 per arm) will be randomized. Stratification Factors: Patients will be stratified according to baseline EPIC bowel and urinary domain scores and country of treatment. Enrollment: Eleven patients. Clinical trial information: NCT04984343 .

Efficacy and safety of darolutamide (DARO) in combination with androgen-deprivation therapy (ADT) and docetaxel (DOC) by disease volume and disease risk in the phase 3 ARASENS study

15

Background: In ARASENS (NCT02799602), DARO plus ADT and DOC significantly reduced the risk of death by 32.5% (HR 0.68; 95% CI: 0.57–0.80; P<0.0001) vs placebo (PBO) + ADT + DOC in patients (pts) with metastatic hormone-sensitive prostate cancer (mHSPC), with similar overall incidences of treatment-emergent adverse events (TEAEs) between groups. The effect of DARO on overall survival (OS) was consistent across prespecified subgroups, including de novo and recurrent disease. For pts with mHSPC, outcomes based on disease volume and risk provide additional information to clinicians. Methods: Pts with mHSPC were randomized 1:1 to DARO 600 mg twice daily or PBO, with ADT + DOC. High-volume disease was defined as visceral metastases and/or ≥4 bone metastases with ≥1 beyond the vertebral column/pelvis (CHAARTED criteria). High-risk disease was defined as ≥2 risk factors: Gleason score ≥8, ≥3 bone lesions, and presence of measurable visceral metastasis (LATITUDE criteria). OS for these subgroups was assessed using an unstratified Cox regression model. Results: Of 1305 pts in the full analysis set, 1005 (77%) had high-volume disease, 912 (70%) had high-risk disease, 300 (23%) had low-volume disease, and 393 (30%) had low-risk disease. DARO + ADT + DOC prolonged OS regardless of high- or low-volume disease with HRs of 0.69 and 0.68 vs PBO + DOC + ADT, respectively. OS benefit of DARO vs PBO was also similar for pts with high- or low-risk disease. DARO improved clinically relevant secondary endpoints vs PBO in high/low-volume and risk subgroups, with HRs generally in the range of those observed in the overall population. Incidences of TEAEs were consistent with the overall ARASENS population across subgroups by high/low volume and high/low risk. Conclusions: In pts with mHSPC, the benefits of early treatment intensification with DARO + ADT + DOC on OS and key pt-relevant secondary efficacy endpoints vs PBO + ADT + DOC were similar in patients with high- and low-volume as well as high- and low-risk mH+SPC. The favorable safety profile of DARO was reconfirmed in high/low-volume and high/low-risk populations. DARO + ADT + DOC sets a new standard of care for pts with mHSPC. Clinical trial information: NCT02799602 . [Table: see text]

TRIUMPH: Phase II trial of rucaparib monotherapy in patients with metastatic hormone-sensitive prostate cancer harboring germline DNA repair gene mutations

190

Background: Androgen deprivation therapy (ADT) is the backbone of treatment for patients (pts) with metastatic prostate cancer (PCa), but many pts find this difficult to tolerate. Treatment with non-castrating regimens may avoid or delay the toxicities of hormonal therapy. The activity of PARP inhibitors (PARPi) in pts with homologous recombination DNA-repair (HRD) mutations (muts) and metastatic castration-resistant PCa has been established. We hypothesized here that the benefit of ARPi can be maintained in the absence of ADT in a biomarker-selected (HRD mutated) population with PCa. We designed a Phase 2 study in men with hormone-naïve, metastatic PCa who harbored a germline HRD mut treated with rucaparib monotherapy (without ADT). Methods: This was a multi-center, single arm Phase 2 study (NCT03413995) in men with asymptomatic hormone-sensitive metastatic PCa who received rucaparib 600mg by mouth daily. During consenting, pts were informed and had to opt out of ADT-based therapy. Pts must have had a germline mutation in an HRD gene on clinical-grade testing. The primary endpoint was confirmed PSA50 response rate. Key secondary endpoints included safety, objective response rate (ORR), and radiographic progression-free survival (rPFS). The trial was designed to detect a 25% absolute increase in PSA50 response from a null of 50%. Results: 12 pts were enrolled, 7 with BRCA1/2 and 5 with CHEK2 muts. The confirmed PSA50 response rate to rucaparib was 41.7% (N=5/12, 95% CI: 19.3-68.1%), which did not meet the pre-specified efficacy boundary to enroll additional patients to 2nd stage. In pts with measurable disease, the ORR was 60% (N=3/5, all with BRCA2). Median rPFS on rucaparib was 10.3 months (95% CI: 4.0 mo - NR). At the time of the interim analysis, 3 pts remained on study. The majority of adverse events (AE) were Grade ≤2 and expected. Translational studies are ongoing. Conclusions: Rucaparib can induce clinical responses in a biomarker-selected PCa population without concurrent ADT. However, the pre-specified threshold of PSA50 response was not met. Although durable responses were observed in a subset of pts, PARPi without ADT in metastatic hormone sensitive PCa will not be pursued. Clinical trial information: NCT03413995 . [Table: see text]

Updated outcomes in TROPHY-U-01 cohort 1, a phase 2 study of sacituzumab govitecan (SG) in patients (pts) with metastatic urothelial cancer (mUC) that progressed after platinum (PT)-based chemotherapy and a checkpoint inhibitor (CPI)

526

Background: SG is an antibody-drug conjugate composed of an anti-Trop-2 antibody coupled to SN-38, a topoisomerase-I inhibitor, via a proprietary hydrolyzable linker. SG received accelerated FDA approval in April 2021 in pts with mUC who previously received PT-based therapy and a CPI based on the primary analysis of the pivotal TROPHY-U-01 Cohort 1 study. With 9.1 mo median (med) follow-up, SG monotherapy demonstrated a 27% objective response rate (ORR) and med overall survival (OS) of 10.9 mo in 113 pts with locally advanced or mUC progressing after receiving at least a PT-based therapy and a CPI (Tagawa, et al. J Clin Oncol. 2021). Here we report updated Cohort 1 outcomes. Methods: TROPHY-U-01 (NCT03547973) is a multicohort, open-label, phase 2 study. Cohort 1 pts (≥18 y) had progression of mUC following PT (as first-line metastatic therapy or as (neo)adjuvant therapy with recurrence/progression ≤12 mo) and CPI, had ECOG PS 0-1, and creatinine clearance ≥30 mL/min. Pts received 10 mg/kg of SG intravenously on D1 and D8 of 21-D cycles. The primary endpoint was ORR per central review by RECIST 1.1. Key secondary endpoints included duration of response (DOR), progression-free survival (PFS), clinical benefit rate (CBR), OS, and safety. Results: As of July 26, 2022, med follow-up was 10.5 mo (range, 0.3-40.9) for treated pts (N=113). As previously reported, pts (78% men; med age, 66 y; 66% with visceral metastases, 34% liver), were heavily pretreated with a med of 3 prior therapies (range, 1-8). Med time since last prior therapy was 1.5 mo (range, 0-60.0). At data cutoff, per central review, ORR was 28% (95% CI, 20.2-37.6); CBR was 38% (95% CI, 29.1-47.7), med DOR was 6.1 mo (95% CI, 4.7-9.7, n=32) and med PFS was 5.4 mo (95% CI, 3.5-6.9). Med time to response was 1.6 mo (range, 1.2-5.6) and med OS was 10.9 mo (95% CI, 8.9-13.8). DOR, PFS, and OS rates (95% CI) at 12 mo were 30% (13.6-48.8), 14% (7.2-23.3), and 45% (35.4-53.8), respectively, with 7 (6%) pts still receiving SG at 12 mo. In pts who received prior enfortumab vedotin (n=10) and prior PT in the (neo)adjuvant setting (n=39), results were consistent with the overall population. Grade ≥3 treatment-related adverse events (TRAEs) occurred in 65% of pts and were similar to prior reports; the most common Grade ≥3 TRAEs were neutropenia (35%), leukopenia (18%), anemia (14%), diarrhea (10%), and febrile neutropenia (10%). One treatment-related death occurred due to febrile neutropenia-related sepsis. Conclusions: At 10.5-mo med follow-up, the response rate remains high in pts with heavily pretreated mUC, including pts with visceral metastases, prior EV therapy and prior (neo)adjuvant PT therapy. No new safety signals were observed. These data support the use of SG in pts with mUC who received PT and a CPI and further evaluation of SG in earlier lines of therapy. Clinical trial information: NCT03547973 .

Dosing, safety, and pharmacokinetics (PK) of combination therapy with darolutamide (DARO), androgen-deprivation therapy (ADT), and docetaxel (DOC) in patients with metastatic hormone-sensitive prostate cancer (mHSPC) in the ARASENS study

148

Background: In ARASENS (NCT02799602), DARO in combination with ADT and DOC significantly reduced the risk of death by 32.5% (HR 0.68; 95% CI 0.57–0.80; P<0.001) vs placebo (PBO) + ADT + DOC in patients with mHSPC. Incidences of treatment-emergent adverse events (TEAEs) were similar between treatment groups. We report dosing, safety, and PK of coadministration of DARO and DOC with ADT. Methods: Patients with mHSPC were randomized 1:1 to DARO 600 mg twice daily or PBO, plus ADT and DOC (75 mg/m2 q21d for 6 cycles). The effect of DARO on DOC PK was assessed by noncompartmental analysis from the first 25 patients with dense PK data and by population PK (PopPK) for all patients. DARO PK from ARASENS were compared with PK data from ARAMIS (NCT02200614; without DOC) to evaluate the impact of DOC on DARO PK. Results: Of 1306 randomized patients, 1305 were included in the full analysis set (DARO, n=651; PBO, n=654). The median treatment duration was longer with DARO vs PBO (41.0 vs 16.7 months) and more DARO-treated patients (45.9% vs 19.1%) were still receiving treatment at primary analysis cutoff (Oct 25, 2021). Almost all patients completed 6 cycles of DOC in both groups (DARO, 87.6%; PBO, 85.5%). The proportion of patients requiring DOC dose modification (interrupted/delayed or reduced) was similar between groups (DARO, 60.0%; PBO, 62.9%). TEAEs led to discontinuation/reduction of DOC in 8.0%/19.9% of DARO patients and 10.3%/19.5% of PBO patients. PopPK analysis indicated that DOC PK in ARASENS was generally consistent with that in the literature. A slight numeric increase in DOC exposure was observed in the DARO + DOC + ADT arm, with 15% higher maximum plasma concentration (geometric mean, 1.93 vs 1.68 µg/mL) and 6% higher area under the concentration-time curve (AUC0-tlast within an 8-hour sampling interval, 2.10 vs 1.99 µg·h/mL) vs PBO + DOC + ADT. This small numeric increase is likely not clinically relevant given the variability in DOC exposure (coefficient of variation, 23%–54%). PK meta-analysis of ARASENS and, which considered patients’ intrinsic characteristics as covariates (eg, age, body weight, region), indicated a 10% lower AUC0-12ss of DARO in patients receiving DOC vs those not receiving DOC, which is not considered clinically relevant. Conclusions: The combination of DARO + DOC + ADT increases overall survival with similar overall incidence of TEAEs and no observed drug-drug interactions between DARO and DOC. DARO can be effectively and safely administered with DOC in patients with mHSPC without clinically relevant changes in PK of DARO or DOC. Clinical trial information: NCT02799602 .

Baseline characteristics from a retrospective, observational, US-based, multicenter, real-world (RW) study of avelumab first-line maintenance (1LM) in locally advanced/metastatic urothelial carcinoma (la/mUC) (PATRIOT-II)

465

Background: The JAVELIN Bladder 100 clinical trial demonstrated a significant overall survival and progression-free survival benefit with avelumab 1LM + best supportive care (BSC) vs BSC alone for la/mUC not progressing on platinum-based chemotherapy (PBC). PATRIOT-II aims to describe RW data for avelumab 1LM treatment (tx) of patients (pts) with la/mUC. Methods: PATRIOT-II collected data from pts with la/mUC treated in 37 geographically dispersed oncology practices/communities and academic centers in the US. Pts who initiated avelumab 1LM following PBC were retrospectively enrolled and will be followed up via medical record review for 52 weeks post avelumab 1LM initiation. This analysis focused on pt characteristics and tx data from la/mUC diagnosis through the PBC period and at avelumab 1LM initiation. Disease and PBC tx characteristics, as well as response to PBC, were assessed. All analyses were descriptive. Results: A total of 160 pts were enrolled (Table), 118 (74%) were white, non-Hispanic, 16 (10%), were Black, Asian, or Hispanic, and the rest unknown; 102 (64%) were current or former smokers. 77 (48%) were tested for PD-L1 via various assays, with 44 (57%) of those tumor samples reported as positive. 1L PBC was cisplatin-based in 100 (63%) of pts and carboplatin-based in 60 (38%). Pts received a median of 4 PBC cycles (interquartile range [IQR], 3-6) for a median of 13 weeks (IQR, 10-17). 31 (19%) discontinued PBC due to unacceptable side effects/toxicity. Best observed response was complete response in 21 (13%), partial response in 109 (68%), and stable disease in 17 (11%), with the remainder unknown. Median time to first imaging was 10 weeks (IQR, 5-14) after PBC initiation. 23 (14%) were hospitalized while receiving PBC, and 25 (16%) were seen in the emergency department. Pts proceeded to avelumab 1LM at a median of 4 weeks (IQR, 3-6) following PBC completion. Avelumab was administered at 800 mg every 2 weeks in 130 (81%), 10 mg/kg in 15 (9%), <800 mg in 8 (5%), and >800 mg in 7 (4%) pts. Conclusions: This ‘RW’ study offers valuable insights into characteristics and outcomes of pts with la/mUC treated in the US. Baseline factors, tx patterns and response to PBC were consistent with usual therapy paradigms in the 1L induction setting. Ongoing trials are evaluating the optimal number of PBC cycles and predictive biomarkers. Limitations include the retrospective nature, lack of randomization and central review, potential selection and confounding biases. [Table: see text]

Randomized trial of MRI-guided salvage radiotherapy for prostate cancer in 4 weeks vs. 2 weeks (SHORTER)

TPS400

Background: The objective of this randomized clinical trial is to demonstrate that 2 weeks (5 fractions) of real-time MRI-guided radiotherapy (RT) with an MR Linac does not significantly increase patient-reported GI and GU symptoms compared to 4 weeks (20 fractions) of RT 2 years after treatment completion. Methods: Key Eligibility Criteria: Inclusion Criteria 1. Men aged > 18 with histologically confirmed prostate cancer after prostatectomy with detectable PSA. 2. KPS > 70. 3. Patients with no evidence of distant metastatic disease on PET/CT/MRI/bone scan< 180 days prior to enrollment. 4. Ability to receive MRI-guided radiotherapy. 5. Ability to complete the Expanded Prostate Cancer Index Composite (EPIC) questionnaire. Exclusion Criteria 1. Prior history of receiving pelvic RT. 2. Patient with history of IBD. 3. History of bladder neck or urethral stricture. Study Design/Endpoints: This is a randomized phase II non-inferiority trial comparing 5 fractions of ultrahypofractionated RT (32.5 Gy total with optional PSMA/MRI boost to 40 Gy) versus 20 fractions of hypofractionated RT (55 Gy total with optional PSMA/MRI boost to 60 Gy) in the post-operative setting for prostate cancer. Subjects will be stratified based on pre-specified stratification factors and randomized 1:1 to receive 5 or 20 fractions using permuted block randomization. The primary endpoint is the change in patient-reported GI and GU symptoms as measured by EPIC at 2 years from end of treatment. Secondary endpoints will include both the safety endpoints including change in GI and GU symptoms at 3, 6, 12 and 60 months from end of treatment, and multiple efficacy endpoints including time to progression, prostate cancer specific survival and overall survival. Sample Size: The sample size is calculated based on a non-inferiority design. The non-inferiority margins are set to be a change score of 6 points for the GI symptoms and 5 points for the GU symptoms. The standard deviations of the change scores are assumed to be 13.2 for the GI symptoms and 10.5 for the GU symptoms based on estimates generated in RTOG 0415 trial. This level of change in scores are deemed as clinically meaningful. For example, 6 points of change score for GI symptoms corresponds to two symptoms worsening by 1 level (i.e., loose stools and frequency of bowel movements change from “no problem” to “very small problem”) or one of the symptoms worsening by 2 levels (i.e., loose stool change from “no problem” to “small problem”). A sample size of 122 with 61 in each arm will ensure 80% power for GI endpoint and 83% power for GU endpoint to detect non-inferiority using a one-sided two-sample t-test at the significance level of 0.05. Adjusting for a projected 10% EPIC/non-compliance rate, 136 patients (68 per arm) will be randomized. Stratification Factors: Patients will be stratified according to baseline EPIC bowel and urinary domain scores and use of nodal treatment and ADT. Enrollment: 91 patients. Clinical trial information: NCT04422132 .

Primary analysis of TROPHY-U-01 cohort 2, a phase 2 study of sacituzumab govitecan (SG) in platinum (PT)-ineligible patients (pts) with metastatic urothelial cancer (mUC) that progressed after prior checkpoint inhibitor (CPI) therapy

520

Background: Pts with PT-ineligible mUC have limited treatment options following CPI therapies; thus, new treatment options are needed. SG is an antibody-drug conjugate composed of an anti-Trop-2 antibody coupled to SN-38, a topoisomerase-I inhibitor, via a proprietary hydrolyzable linker. SG received accelerated FDA approval in April 2021 for pts with mUC who progressed after PT and CPI therapies based on the positive results of the pivotal TROPHY-U-01 Cohort 1 study. In Cohort 1, SG demonstrated an objective response rate (ORR) of 27%, a median overall survival (OS) of 10.9 mo, and a manageable safety profile in 113 pts with locally advanced or mUC (Tagawa, et al. J Clin Oncol. 2021). SG demonstrated an ORR of 28% in PT-ineligible pts with mUC who progressed after CPI therapy in preliminary results of the phase 2 TROPHY-U-01 Cohort 2 study (Petrylak et al. J Clin Oncol. 2020). Here, we report the primary analysis of TROPHY-U-01 Cohort 2. Methods: Cohort 2 pts (≥18 y) were PT-ineligible at screening, had ECOG PS 0-1, and creatinine clearance ≥30 mL/min. Pts received 10 mg/kg of SG on D1 and D8 of 21-day continuous cycles. The primary endpoint was ORR per central review by RECIST 1.1. Secondary endpoints included duration of response (DOR) and progression-free survival (PFS), per central review, and OS. Target enrollment was approximately 40 pts. Assuming the second-line ORR of 40%, 40 pts would give a 95% CI with a lower limit of 25% (CI is 0.25 to 0.57) for ORR. Results: As of July 26, 2022, the median follow-up was 9.3 mo (range, 0.5-30.6) for treated pts (N=38); median age, 72.5 y (range, 41-87), 61% male, 50% ECOG PS 1, and 66% visceral metastases (29% liver). Median number of prior therapies was 2 (range, 1-5); 50% received prior (neo)adjuvant PT, 18% received prior enfortumab vedotin, and 3% received prior erdafitinib. Median time since last prior anticancer therapy was 1.6 mo (range, 1-8) and median duration of last prior anticancer therapy was 4.2 mo (range, 1-12). Per central review, ORR was 32% (95% CI, 17.5-48.7; 32% partial response); median DOR was 5.6 mo (95% CI, 2.8-13.3; n=12); and median PFS was 5.6 mo (95% CI, 4.1-8.3). Median time to response was 1.4 mo (range, 1.3-1.5) and median OS was 13.5 mo (95% CI, 7.6-15.6). Grade ≥3 treatment-related adverse events (TRAEs) occurred in 68% of pts; the most common Grade ≥3 TRAEs were neutropenia (34%), anemia (21%), leukopenia (18%), fatigue (18%), and diarrhea (16%). TRAEs resulted in an 18% discontinuation rate. No treatment-related deaths were reported. Conclusions: SG monotherapy demonstrated a high response rate with an overall manageable safety profile in PT-ineligible pts with mUC who progressed after CPI therapy. No new safety signals were observed. These data support further evaluation of SG in pts with mUC post CPI therapy. Clinical trial information: NCT03547973 .

A phase I/II dose-escalation study of fractionated 225Ac-J591 for progressive metastatic castration-resistant prostate cancer (mCRPC) in patients with prior treatment with 177Lu-PSMA

TPS288

Background: As prostate-specific membrane antigen targeted radiotherapy (PSMA-TRT) is now an active standard-of-care treatment in mCRPC, ongoing studies with alternative approaches to targeting PSMA will increasingly need to consider the consequences of sequential PSMA-TRT exposure. Our past and ongoing investigations into antibody-based targeting (e.g., J591) and potent alpha emitting payloads (e.g., 225Ac) impact drug kinetics, biodistribution, and resultant clinical toxicities. In a first-in-human phase I dose-escalation study of 225Ac-J591, patients with mCRPC were treated with a single dose of 225Ac-J591 on seven dose levels, up to 93.3 KBq/kg without achievement of maximal tolerated dose (MTD). One patient treated at 80 KBq/kg developed dose-limiting toxicity (DLT) of Gr 4 anemia and thrombocytopenia, but 0 of 6 at 93.3 KBq/Kg had Gr > 3 heme toxicity or Gr > 2 non-heme toxicity. Although not intentionally preselected for prior exposure, 55% (12/22) of patients had 177Lu-PSMA previously. With approval of 177Lu vipivotide tetraxetan, we amended an ongoing phase I dose-escalation study to include a post-177-Lu-PSMA cohort. Methods: Entry criteria include progressive mCRPC by PCWG3 criteria, ECOG PS 0-2, intact organ function, and prior receipt of AR pathway inhibitor and chemotherapy (or refused/ineligible). There is no limit to prior lines of therapy except alpha-emitting therapies (i.e., PSMA-TRT, 223Ra) and in this amended dose-escalation cohort, all patients must have had prior treatment with 177Lu-PSMA. Treatment will be given in a single fractionated cycle of 225Ac-J591 administered on D1 and D15. The phase I component is a 3+3 dose-escalation study design with up to 18 patients, with the goal of identifying MTD. The phase II component will include up to 16-19 patients in a Simon 2-stage design with 90% power to exclude the null hypothesis (35% or fewer patients with PSA50). Eligible men with negative PSMA PET scans will be offered treatment with informed consent in an exploratory subgroup but will not be counted towards phase II efficacy. Secondary outcomes include radiographic response by PCWG3-modified RECIST 1.1 criteria and PSMA PET, biochemical and radiographic progression-free survival, circulating tumor cell counts, and overall survival. Patient reported outcomes, genomic, and immune analyses are exploratory. Enrollment to the post-177Lu-PSMA cohort began in August 2022. Clinical trial information: NCT04506567 .

Avelumab first-line (1L) maintenance for advanced urothelial carcinoma (UC): Long-term follow-up from the JAVELIN Bladder 100 trial in subgroups defined by 1L chemotherapy regimen and analysis of overall survival (OS) from start of 1L chemotherapy

508

Background: For platinum-eligible patients (pts) with advanced UC, 1L cisplatin- or carboplatin-based chemotherapy regimens followed by avelumab maintenance in pts without progression has become the standard of care. This is based on the results of the phase 3 JAVELIN Bladder 100 trial (NCT02603432), which showed significantly longer OS and progression-free survival (PFS) from start of maintenance (randomization) with avelumab maintenance + best supportive care (BSC) vs BSC alone (median OS, 23.8 vs 15.0 months; HR, 0.76 [95% CI, 0.63-0.91]; p=0.0036). We report post hoc analyses of long-term outcomes by 1L chemotherapy regimen and OS from start of 1L chemotherapy. Methods: Pts with unresectable locally advanced or metastatic UC that did not progress with 4-6 cycles of 1L cisplatin + gemcitabine or carboplatin + gemcitabine were randomized 1:1 to receive avelumab + BSC (n=350) or BSC alone (n=350). The primary endpoint was OS measured from randomization. Secondary endpoints included PFS and safety. Results: At data cutoff (June 4, 2021), median follow-up from randomization was ≥38 months in both arms. In subgroups treated with 1L cisplatin + gemcitabine or carboplatin + gemcitabine, OS and PFS (measured from start of maintenance [randomization]) were longer in the avelumab + BSC arm than in the BSC alone arm (Table). Safety findings were similar in both subgroups. In the overall population, median OS measured from the start of 1L chemotherapy was 29.7 months (95% CI, 25.2-34.0) in the avelumab + BSC arm and 20.5 months (95% CI, 19.0-23.5) in the BSC alone arm (HR, 0.77 [95% CI, 0.635-0.921]). Conclusions: Long-term follow-up from the JAVELIN Bladder 100 trial confirms that avelumab 1L maintenance provides similar OS and PFS benefits in pts with advanced UC who are progression free following standard-of-care 1L cisplatin- or carboplatin-based chemotherapy, with an acceptable safety profile. The median OS measured from start of chemotherapy further supports the use of avelumab 1L maintenance as standard of care in this setting and provides a benchmark for future clinical trials. Clinical trial information: NCT02603432 . [Table: see text]

Increased utilization of prostate-specific membrane antigen (PSMA)-targeted radionuclide therapy (PSMA-TRT) in African American (AA) patients at an academic medical center

36

Background: At Weill Cornell Medicine (WCM), we have had a research program utilizing anti-PSMA mAb J591 since the year 2000. With the addition of PSMA ligand-based therapies in 2017, we have enrolled around 300 patients on investigational PSMA-TRT clinical trials. Since the approval of 177Lu-PSMA-617 (Pluvicto; Lu-177 vipivotide tetraxetan), we began standard-of-care (SOC) treatment, co-enrolling willing patients into a research registry. Recognizing the low numbers of AA patients enrolled on therapeutic clinical trials in the U.S., we made a concerted effort to increase the number of AA patients with prostate cancer (PC) enrolled on clinical trials at WCM. We retrospectively assessed the demographic data of patients enrolled on PSMA-TRT clinical trials to determine changing patterns of enrollment, and to determine if our efforts have improved access to these novel treatments for this under-represented, but high-risk population of patients. Methods: We collected demographic data (namely race and ethnicity) on patients with PC from WCM who were included on our PSMA-TRT investigational clinical trial databases or enrolled on our SOC 177Lu-PSMA-617 research registry. We used self-reported race and, when not available (due to patient death or loss of follow-up), demographic information documented in the medical record. Patients were grouped into 5-year cohorts based on either the date of consent for trial enrollment, or the start date of PSMA-TRT treatment (based on available information). Institutional tumor registry data was used as a comparator to assess the total percentage of AA patients with PC seen at WCM. Results: The percentages of patients included on PSMA-TRT clinical trials at WCM who were identified as AA were as follows: 2000-2004: 3.1% (2/65), 2005-2009: 5.1% (3/59), 2010-2014: 6.1% (2/33), and 2015-2019: 5.9% (5/85). The percentage of AA patients on PSMA-TRT studies from 2020 through July 2022 was 18.2% (16/88, inclusive of 8/72 investigational TRT subjects and 8/16 SOC registry participants). The total percentages of AA patients seen at Cornell based upon analysis of our tumor registry data were as follows: 2000-2004: 10.5% (182/1728), 2005-2009: 6.9% (250/3607), 2010-2014: 10% (326/3255), 2015-2019: 11.5% (278/2413), and 2020: 14.1%. Tumor registry data for 2021-present were not yet available. Conclusions: The percentage of AA patients on investigational PSMA-TRT trials at our institution notably increased from 2000-2019 (3.1%-6.1%) to 2020-2022 (11.1%). Moreover, 50% of those treated with 177Lu-PSMA-617 since its FDA approval and co-enrolled on our research registry identified as AA. These data suggest that outreach and increasing access to AA patients for novel PC treatment such as PSMA-TRT can result in increased numbers of underrepresented patients enrolling on clinical trials and receiving the most modern standards of care (i.e., PSMA-TRT).

Phase I results of a phase I/II study of pembrolizumab and AR signaling inhibitor (ARSI) with 225Ac-J591

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Background: Only a small fraction of patients with PC respond to immunotherapy; radiation increases responses. PSMA targeted radionuclide therapy (PSMA-TRT) radiates multiple sites of disease simultaneously. ARSI can lead to radiosensitization and upregulate PSMA and PD-L1 expression. We hypothesize that the addition of potent alpha-PSMA-TRT (225Ac-J591) will lead to double-stranded DNA breaks, cell death, and subsequent release of neoantigens, thereby increasing the response proportion and duration to pembrolizumab plus ARSI. Here, we present preliminary phase I results of a phase I/II study, including an unexpected cytokine release syndrome (CRS). Methods: Eligibility: Progressive mCRPC by PCWG3 criteria (at least one ARSI, no chemotherapy in the mCRPC setting). Patients received ARSI of physician’s choice, pembrolizumab (400mg every 6 weeks), and single infusion of 225Ac-J591 at two different dose levels (65 or 80 KBq/kg). The primary endpoint for phase I is determination of 225Ac-J591 dose for phase II in a pick-the-winner design. Results: 12 patients were treated (6 at 65 KBq/kg, 6 at 80 KBq/kg). 7 (58%) received enzalutamide, 3 (25%) apalutamide, and 2 (17%) darolutamide. Median age 66.5, median PSA 7.75 ng/mL, 6 (50%) CALGB intermediate risk, 4 (33%) low risk, 11 (92%) with bone metastases, 3 (25%) with nodal metastases. 7 (58%) with prior abiraterone, 6 (50%) prior enzalutamide, 5 (42%) sip-T. All patients experienced PSA decline following therapy, 6 (50%) with >50% decline. With >6 months follow-up, 4 (33%; all at 80 KBq/kg) remain progression-free and on study. Of note, 7 (58%) developed an unexpected CRS 7-14 days following treatment characterized by morbilliform rash, fever >101F, and low blood counts. Inflammatory markers were elevated: IL-6 (2.1-7.7 pg/mL), D-Dimer (306-2378 ng/mL), ferritin (361.3-513.4 ng/mL), fibrinogen (386-461 mg/dL), ESR (16-42 mm/hr). After pausing the ARSI, this reaction improved within 1 week. Thrombocytopenia and/or neutropenia occurred during this syndrome, then typically improved before counts fell again at expected nadir 4 weeks after 225Ac-J591. Overall AEs on study include: 9 (75%) thrombocytopenia (3 with g≥3; 1 g4 with PC marrow infiltration), 7 (58%) neutropenia (none g≥3), 6 (50%) nausea, 7 (58%) g1-2 fatigue, 9 (75%) g1-2 xerostomia, 7 (58%) g1 AST. In contrast to heme AEs with unexpected initial occurrence during CRS followed by typical nadir from TRT, the described non-hematologic AEs were generally independent of CRS. 4 (33%) developed typical irAEs: 2 with rash (D60, D62) and 2 hypothyroidism (D77, D82). Conclusions: Combination therapy with alpha-PSMA-TRT, ARSI, and pembrolizumab demonstrates efficacy in the phase I run-in. A key safety signal that has emerged with triplet therapy is CRS that can be managed supportively. The randomized phase II component is accruing with additional safety visits and sample collection for cytokine analysis. Clinical trial information: NCT04946370 .

Primary analysis of TROPHY-U-01 cohort 3, a phase 2 study of sacituzumab govitecan (SG) in combination with pembrolizumab (Pembro) in patients (pts) with metastatic urothelial cancer (mUC) that progressed after platinum (PT)-based therapy

518

Background: Pembro is standard of care for pts with mUC who progress after 1L PT therapy but only ~21% of pts respond, highlighting an unmet need (Bellmunt, et al. NEJM. 2017). SG is an antibody-drug conjugate composed of an anti-Trop-2 antibody coupled to SN-38 via a hydrolyzable linker. In Cohort 1 of the TROPHY-U-01 study, SG demonstrated a 27% objective response rate (ORR) with manageable safety in 113 pts with locally advanced or mUC who previously received PT and a checkpoint inhibitor (CPI; Tagawa, et al. J Clin Oncol. 2021), leading to accelerated FDA approval in this pt population. Preliminary results of the phase 2 TROPHY-U-01 Cohort 3 study showed that SG plus Pembro demonstrated a high ORR (34%) as a 2L therapy in 41 CPI-naive pts with mUC who progressed after PT (Grivas et al. J Clin Oncol. 2021). Here we present the primary analysis of Cohort 3. Methods: Cohort 3 pts (≥18 y) had progression of mUC following PT in the metastatic setting or following ≤12 mo of PT in the (neo)adjuvant setting and ECOG PS 0-1. Pts received 10 mg/kg of SG on D1 and D8 and 200 mg of Pembro on D1 of a 21-D cycle for ≤2 y. The primary endpoint was ORR [complete response (CR) + partial response (PR)] per central review by RECIST 1.1. Secondary endpoints include clinical benefit rate [CBR; CR + PR + stable disease for at least 6 mo], duration of response (DOR) and progression-free survival (PFS) per central review; and safety. Target enrollment was approximately 41 pts based on a Simon two-stage design for 90% power at one-sided α of 0.05 to demonstrate 21% improvement in ORR, with a null hypothesis of historical ORR ≤20% and an alternate hypothesis of ORR ≥41%. Results: As of July 26, 2022, median follow-up was 12.5 mo (range, 0.9-24.6) for treated pts (N=41); median age, 67 y (range, 46-86), 83% male, 61% ECOG PS 1, 76% ≥1 Bellmunt risk factors, and 78% visceral metastases (29% liver). Median duration of last prior anti-cancer therapy was 2.7 mo (range, 0-13). Per central review, ORR was 41% (95% CI, 26.3-57.9; 20% CR); CBR was 46% (95% CI, 30.7-62.6); median DOR was 11.1 mo (95% CI, 4.8-NE [not estimable]; n=17); and median PFS was 5.3 mo (95% CI, 3.4-10.2). Median time to response was 1.4 mo (95% CI, 1.3-2.7) and median OS was 12.7 mo (95% CI, 10.7-NE). Grade ≥3 treatment-related adverse events (TRAEs) occurred in 61% of pts; most common Grade ≥3 TRAEs were neutropenia (37%; 10% febrile neutropenia), leukopenia (20%), and diarrhea (20%). TRAEs led to a 15% discontinuation rate. Systemic steroid and G-CSF use were both 34%. No treatment-related death occurred. Conclusions: SG plus Pembro demonstrated a high ORR and CBR with a manageable safety profile in 2L mUC in CPI-naive pts who progressed after PT-based therapy. No new safety signals were observed with the combination. These data support further evaluation of SG plus CPI in mUC. Clinical trial information: NCT03547973 .

Use of a navigable interface for integrated whole genome and transcriptome sequencing as a platform for pursuit of therapeutic targets in advanced prostate cancers

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Background: Metastatic, castration-resistant prostate cancer (mCRPC) is commonly the deadly form of PC. Among these, a subset of tumors are androgen-indifferent with the most aggressive often manifesting variant histology, including neuroendocrine or small cell changes. Neuroendocrine PC can be de novo (NEPC) or develop in response to therapy as treatment emergent (CRPC-NE). Currently effective durable treatments for NEPC are lacking. Hence, we sought to identify additional targets in CRPC/NEPC using an integrative platform of whole genome (WGS) and transcriptome sequencing (RNAseq). Methods: WGS was performed on55 tumor/normal pairs (CRPC-Ad, n= 32; CRPC-NE, n=13; de novo NEPC, n=7; metastatic hormone naïve, PC n=3) from 48 patients. RNAseq data was available in a subset of 21 samples. We employed the Isabl GxT analytic platform and manually curated single base substitution (SBS, COSMIC v3) molecular signatures and structural variants (SV) that involved tumor suppressor genes and oncogenes. Results: We observed 184 events in cancer-associated genes and targets in 38 cases. Non-canonical ETS fusions were identified in 2 CRPC-Ad patients ( MSMB-ERG and YWHAE-ETV4). Other rare events included SVs affecting ALK ( SLC45A3-ALK) and FGFR1 amplification in 1 patient each. Pathogenic germline alterations in 15% of patients with equal frequency in each clinicopathological state. These variants included genes such as BRCA1, BRCA2, and ATM, and other genes of uncertain relevance for prostate cancer ( e.g., PPM1D and MUTYH). SBS genomic signatures associated with homologous recombination deficiency (HRD) were observed in 15% of the patients (7 cases): 3 harbored germline BRCA1/2mutations, 2 with somatic BRCA2 mutations, and 2 without alteration in BRCA1/2 (1 of these CRPC-Ad had a complex SV disrupting RAD51B) without apparent enrichment for any histology, and a majority of both histologies were enriched in Mismatch repair (MMR)-associated SBS. One subject CRPC-NE and amphicrine character, which displayed a complete response to immune checkpoint blockade, harbored driver mutations in AR and CTNNB1, and homozygous loss of MSH2/6. Further, molecular signatures of potential clinical relevance were detected at varying contributions and included CDK12-type genomic instability (CRPC-Ad, n=2) (4%) and MMR deficiency with POLD1 proofreading (CRPC-Ad) who also experienced a durable response to pembrolizumab. Conclusions: WGS/RNAseq in CRPC and NEPC elucidates genomic signatures associated with HRD and MMR, complex SVs in oncogenes, and non-canonical ETS fusions. Expansion of our analysis is underway with enhanced integration of clinical metadata and RNAseq for rational trial design for aggressive variant CRPC and NEPC.

Differential responses to taxanes and PARP inhibitors in ATM- versus BRCA2-mutated metastatic castrate-resistant prostate cancer

BACKGROUND

PARP (poly(ADP-ribose) polymerase) inhibitors (PARPi) are now standard of care in metastatic castrate-resistant prostate cancer (mCRPC) patients with select mutations in DNA damage repair (DDR) pathways, but patients with ATM- and BRCA2 mutations may respond differently to PARPi. We hypothesized that differences may also exist in response to taxanes, which may inform treatment sequencing decisions.

METHODS

mCRPC patients (N = 158) with deleterious ATM or BRCA2 mutations who received taxanes, PARPi, or both were retrospectively identified from 11 US academic centers. Demographic, treatment, and survival data were collected. Kaplan-Meier analyses were performed and Cox hazard ratios (HR) were calculated for progression-free survival (PFS) as well as overall survival (OS), from time of first taxane or PARPi therapy.

RESULTS

Fifty-eight patients with ATM mutations and 100 with BRCA2 mutations were identified. Fourty-four (76%) patients with ATM mutations received taxane only or taxane before PARPi, while 14 (24%) received PARPi only or PARPi before taxane. Patients with ATM mutations had longer PFS when taxane was given first versus PARPi given first (HR: 0.74 [95% confidence interval [CI]: 0.37-1.50]; p = 0.40). Similarly, OS was longer in patients with ATM mutations who received taxane first (HR: 0.56 [CI: 0.20-1.54]; p = 0.26). Among patients with BRCA2 mutations, 51 (51%) received taxane first and 49 (49%) received PARPi first. In contrast, patients with BRCA2 mutations had longer PFS when PARPi was given first versus taxane given first (HR: 0.85 [CI: 0.54-1.35]; p = 0.49). Similarly, OS was longer in patients with BRCA2 mutations who received PARPi first (HR: 0.75 [CI: 0.41-1.37]; p = 0.35).

CONCLUSIONS

Our retrospective data suggest differential response between ATM and BRCA2 mutated prostate cancers in terms of response to PARPi and to taxane chemotherapy. When considering the sequence of PARPi versus taxane chemotherapy for mCRPC with DDR mutations, ATM, and BRCA2 mutation status may be helpful in guiding choice of initial therapy.

FORT-1: Phase II/III Study of Rogaratinib Versus Chemotherapy in Patients With Locally Advanced or Metastatic Urothelial Carcinoma Selected Based on FGFR1/3 mRNA Expression

PURPOSE

Rogaratinib, an oral pan-fibroblast growth factor receptor (FGFR1-4) inhibitor, showed promising phase I efficacy and safety in patients with advanced urothelial carcinoma (UC) with FGFR1-3 mRNA overexpression. We assessed rogaratinib efficacy and safety versus chemotherapy in patients with FGFR mRNA-positive advanced/metastatic UC previously treated with platinum chemotherapy.

METHODS

FORT-1 (ClinicalTrials.gov identifier: NCT03410693) was a phase II/III, randomized, open-label trial. Patients with FGFR1/3 mRNA-positive locally advanced or metastatic UC with ≥ 1 prior platinum-containing regimen were randomly assigned (1:1) to rogaratinib (800 mg orally twice daily, 3-week cycles; n = 87) or chemotherapy (docetaxel 75 mg/m², paclitaxel 175 mg/m², or vinflunine 320 mg/m² intravenously once every 3 weeks; n = 88). The primary end point was overall survival, with objective response rate (ORR) analysis planned following phase II accrual. Because of comparable efficacy between treatments, enrollment was stopped before progression to phase III; a full interim analysis of phase II was completed.

RESULTS

ORRs were 20.7% (rogaratinib, 18/87; 95% CI, 12.7 to 30.7) and 19.3% (chemotherapy, 17/88; 95% CI, 11.7 to 29.1). Median overall survival was 8.3 months (95% CI, 6.5 to not estimable) and 9.8 months (95% CI, 6.8 to not estimable; hazard ratio, 1.11; 95% CI, 0.71 to 1.72; P = .67). Grade 3/4 events occurred in 37 (43.0%)/4 (4.7%) patients and 32 (39.0%)/15 (18.3%), respectively. No rogaratinib-related deaths occurred. Exploratory analysis of patients with FGFR3 DNA alterations showed ORRs of 52.4% (11/21; 95% CI, 29.8 to 74.3) for rogaratinib and 26.7% (4/15; 95% CI, 7.8 to 55.1) for chemotherapy.

CONCLUSION

To our knowledge, these are the first data to compare FGFR-directed therapy with chemotherapy in patients with FGFR-altered UC, showing comparable efficacy and manageable safety. Exploratory testing suggested FGFR3 DNA alterations in association with FGFR1/3 mRNA overexpression may be better predictors of rogaratinib response.

New prognostic model in patients with advanced urothelial carcinoma treated with second-line immune checkpoint inhibitors

BACKGROUND

Bellmunt Risk Score, based on Eastern Cooperative Oncology Group (ECOG) performance status (PS), hemoglobin levels and presence of liver metastases, is the most established prognostic algorithm for patients with advanced urothelial cancer (aUC) progressing after platinum-based chemotherapy. Nevertheless, existing algorithms may not be sufficient following the introduction of immunotherapy. Our aim was to develop an improved prognostic model in patients receiving second-line atezolizumab for aUC.

METHODS

Patients with aUC progressing after cisplatin/carboplatin-based chemotherapy and enrolled in the prospective, single-arm, phase IIIb SAUL study were included in this analysis. Patients were treated with 3-weekly atezolizumab 1200 mg intravenously. The development and internal validation of a prognostic model for overall survival (OS) was performed using Cox regression analyses, bootstrapping methods and calibration.

RESULTS

In 936 patients, ECOG PS, alkaline phosphatase, hemoglobin, neutrophil-to-lymphocyte ratio, liver metastases, bone metastases and time from last chemotherapy were identified as independent prognostic factors. In a 4-tier model, median OS for patients with 0-1, 2, 3-4 and 5-7 risk factors was 18.6, 10.4, 4.8 and 2.1 months, respectively. Compared with Bellmunt Risk Score, this model provided enhanced prognostic separation, with a c-index of 0.725 vs 0.685 and increment in c-statistic of 0.04 (p<0.001). Inclusion of PD-L1 expression did not improve the model.

CONCLUSIONS

We developed and internally validated a prognostic model for patients with aUC receiving postplatinum immunotherapy. This model represents an improvement over the Bellmunt algorithm and could aid selection of patients with aUC for second-line immunotherapy.

TRIAL REGISTRATION NUMBER

NCT02928406.

Safety Profile of Ipatasertib Plus Abiraterone vs Placebo Plus Abiraterone in Metastatic Castration-resistant Prostate Cancer

PURPOSE

Adding ipatasertib to abiraterone and prednisone/prednisolone significantly improved radiographic progression-free survival for patients with metastatic castration-resistant prostate cancer (mCRPC) with PTEN-loss tumours by immunohistochemistry in the IPATential150 trial (NCT03072238). Here we characterise the safety of these agents in subpopulations and assess manageability of key adverse events (AEs).

MATERIALS AND METHODS

In this randomised, double-blind, phase 3 trial, patients with previously untreated asymptomatic or mildly symptomatic mCRPC were randomised 1:1 to receive ipatasertib-abiraterone or placebo-abiraterone (all with prednisone/prednisolone). AEs were analysed, focusing on key AEs of diarrhoea, hyperglycaemia, rash and transaminase increased.

RESULTS

1097 patients received study medication and were assessed for safety (47% with PTEN-loss tumours by immunohistochemistry and 20% were Asian). Ipatasertib was associated with increased Grade 3/4 AEs and AEs leading to treatment discontinuation vs placebo. The rate of discontinuation of ipatasertib was 18% in patients with PTEN-loss and 21% overall. The frequencies of all-grade, Grade 3/4 and serious AEs were similar between the PTEN-loss and overall populations. Diarrhoea, hyperglycaemia, rash and transaminase elevation were more frequent in ipatasertib-treated patients, appearing rapidly after treatment initiation (median onset: 8-43 days for ipatasertib arm and 56-104 days for placebo). The ipatasertib discontinuation rate was 32% and 18% in Asian and non-Asian patients, respectively, despite similar baseline characteristics and Grade 3/4 AE frequencies between groups.

CONCLUSIONS

Ipatasertib plus abiraterone had an overall tolerable safety profile consistent with known toxicities. More AEs leading to drug discontinuation were observed with ipatasertib than placebo, but incidence would likely be lessened with prophylactic measures.

Which traits affect how long patients with advanced prostate cancer live when treated with enzalutamide?

WHAT IS THIS SUMMARY ABOUT?

This is a summary of a research article originally published in European Journal of Cancer. The PROSPER study involved men who had a type of advanced prostate cancer called nonmetastatic castration-resistant prostate cancer (nmCRPC). In men with nmCRPC, their cancer has progressed on traditional hormone therapy but scans show that it has not spread to other parts of the body. The main results of the PROSPER study showed that patients treated with enzalutamide lived longer than patients treated with placebo. For this analysis, researchers looked at whether this was different depending on patients' traits.

WHAT WERE THE RESULTS?

Researchers found that age and location did not affect how long patients lived when treated with enzalutamide. They found three patient traits that did make a difference. Being able to carry out daily activities, low prostate-specific antigen level (PSA level), and receiving no other prostate cancer treatments after the study meant that patients were more likely to live longer.

WHAT DO THE RESULTS OF THE STUDY MEAN?

Patients with nmCRPC treated with enzalutamide lived longer than patients treated with placebo. Age and location did not affect how long these patients lived, but other traits did. Clinical Trial Registration: NCT02003924 (ClinicalTrials.gov).

Case report: Metastatic urothelial cancer with an exceptional response to immunotherapy and comprehensive understanding of the tumor and the tumor microenvironment

Although immune checkpoint inhibitors (ICIs) are increasingly used as second-line treatments for urothelial cancer (UC), only a small proportion of patients respond. Therefore, understanding the mechanisms of response to ICIs is critical to improve clinical outcomes for UC patients. The tumor microenvironment (TME) is recognized as a key player in tumor progression and the response to certain anti-cancer treatments. This study aims to investigate the mechanism of response using integrated genomic and transcriptomic profiling of a UC patient who was part of the KEYNOTE-045 trial and showed an exceptional response to pembrolizumab. Diagnosed in 2014 and receiving first-line chemotherapy without success, the patient took part in the KEYNOTE-045 trial for 2 years. She showed dramatic improvement and has now been free of disease for over 6 years. Recently described by Bagaev et al., the Molecular Functional (MF) Portrait was utilized to dissect genomic and transcriptomic features of the patient's tumor and TME. The patient's tumor was characterized as Immune Desert, which is suggestive of a non-inflamed microenvironment. Integrated whole-exome sequencing (WES) and RNA sequencing (RNA-seq) analysis identified an ATM mutation and high TMB level (33.9 mut/mb), which are both positive biomarkers for ICI response. Analysis further revealed the presence of the APOBEC complex, indicating the potential for use of APOBEC signatures as predictive biomarkers for immunotherapy response. Overall, comprehensive characterization of the patient's tumor and TME with the MF Portrait revealed important insights that could potentially be hypothesis generating to identify clinically useful biomarkers and improve treatment for UC patients.

What Experts Think About Prostate Cancer Management During the COVID-19 Pandemic: Report from the Advanced Prostate Cancer Consensus Conference 2021

Patients with advanced prostate cancer (APC) may be at greater risk for severe illness, hospitalisation, or death from coronavirus disease 2019 (COVID-19) due to male gender, older age, potential immunosuppressive treatments, or comorbidities. Thus, the optimal management of APC patients during the COVID-19 pandemic is complex. In October 2021, during the Advanced Prostate Cancer Consensus Conference (APCCC) 2021, the 73 voting members of the panel members discussed and voted on 13 questions on this topic that could help clinicians make treatment choices during the pandemic. There was a consensus for full COVID-19 vaccination and booster injection in APC patients. Furthermore, the voting results indicate that the expert's treatment recommendations are influenced by the vaccination status: the COVID-19 pandemic altered management of APC patients for 70% of the panellists before the vaccination was available but only for 25% of panellists for fully vaccinated patients. Most experts (71%) were less likely to use docetaxel and abiraterone in unvaccinated patients with metastatic hormone-sensitive prostate cancer. For fully vaccinated patients with high-risk localised prostate cancer, there was a consensus (77%) to follow the usual treatment schedule, whereas in unvaccinated patients, 55% of the panel members voted for deferring radiation therapy. Finally, there was a strong consensus for the use of telemedicine for monitoring APC patients. PATIENT SUMMARY: In the Advanced Prostate Cancer Consensus Conference 2021, the panellists reached a consensus regarding the recommendation of the COVID-19 vaccine in prostate cancer patients and use of telemedicine for monitoring these patients.

Statin and metformin use and outcomes in patients with castration-resistant prostate cancer treated with enzalutamide: A meta-analysis of AFFIRM, PREVAIL and PROSPER

BACKGROUND

Statins and metformin are commonly prescribed for patients, including those with prostate cancer. Preclinical and epidemiologic studies of each agent have suggested anti-cancer properties.

METHODS

Patient data from three randomised, double-blind, placebo-controlled, phase III studies evaluating enzalutamide (AFFIRM, PREVAIL and PROSPER) in patients with castration-resistant prostate cancer were included in this analysis. This post hoc, retrospective study examined the association of statin and metformin on radiographic progression-free survival (rPFS), metastasis-free survival (MFS), toxicity and overall survival (OS). After adjusting for available clinical prognostic variables, multivariate analyses were performed on pooled data from AFFIRM and PREVAIL, all three trials pooled, and each trial individually, to assess differential efficacy in these end-points associated with the baseline use of these medications.

RESULTS

In the multivariate analysis of the individual trials, OS and rPFS/MFS were not significantly influenced by statin or metformin use in AFFIRM or PROSPER. However, in PREVAIL, OS was significantly influenced by statin (hazard ratio [HR] 0.72; 95% confidence interval [CI] 0.59-0.89) and rPFS was significantly influenced by metformin (HR, 0.48; 95% CI 0.34-0.70). In pooled analyses, improved OS was significantly associated with statin use but not metformin use for AFFIRM+PREVAIL trials (HR 0.83; 95% CI 0.72-0.96) and AFFIRM+PREVAIL+PROSPER (HR 0.75; 95% CI 0.66-0.85).

CONCLUSIONS

The association between statin or metformin use and rPFS, MFS and OS was inconsistent across three trials. Analyses of all three trials pooled and AFFIRM+PREVAIL pooled revealed that statin but not metformin use was significantly associated with a reduced risk of death in enzalutamide-treated patients. Additional prospective, controlled studies are warranted.

CLINICAL TRIAL REGISTRATION

AFFIRM (NCT00974311), PREVAIL (NCT01212991) and PROSPER (NCT02003924).

Exposure-response relationship of ramucirumab in RANGE, a randomized phase III trial in advanced urothelial carcinoma refractory to platinum therapy

AIMS

Patients with advanced urothelial carcinoma (UC) who progress after platinum-based chemotherapy have a poor prognosis, and there is a medical need to improve current treatment options. Ramucirumab plus docetaxel significantly improved progression-free survival but not overall survival (OS) in platinum-refractory advanced UC (RANGE trial; NCT02426125). Here, we report the exposure-response (ER) of ramucirumab plus docetaxel using data from the RANGE trial.

METHODS

Pharmacokinetic (PK) samples were collected (cycle 1-3, 5, 9 [day 1] and 30 days from treatment discontinuation), and PK data were analysed using population PK (popPK) analysis. The minimum ramucirumab concentration after first dose administration (Cmin,1 , or trough concentration immediately prior to the second dose) was derived by popPK analysis and used as the exposure parameter for ER analysis. Cox proportional hazards regression models and matched case-control analyses were used to evaluate the relationship between Cmin,1 and OS. The Cmin,1 relationship with safety was assessed descriptively.

RESULTS

Several poor prognostic factors (ECOG 1, haemoglobin concentration <100 g/L, presence of liver metastases) appeared more frequently in the lower exposure quartiles, suggesting a possible disease-PK interaction. A significant association was identified between Cmin,1 and OS (P = .0108). Higher exposure quartiles were associated with longer survival and smaller hazard ratios compared to placebo. No new exposure-safety trends were observed within the exposure range (ramucirumab 10 mg/kg once every 3 weeks).

CONCLUSIONS

This prespecified ER analyses suggests a positive relationship between efficacy and ramucirumab exposure, with an imbalance associated with disease prognostic factors. Further investigation may elucidate a possible disease-PK relationship.