Rucaparib or Physician's Choice in Metastatic Prostate Cancer.

BACKGROUND: In a phase 2 study, rucaparib, an inhibitor of poly(ADP-ribose) polymerase (PARP), showed a high level of activity in patients who had metastatic, castration-resistant prostate cancer associated with a deleterious BRCA alteration. Data are needed to confirm and expand on the findings of the phase 2 study. METHODS: In this randomized, controlled, phase 3 trial, we enrolled patients who had metastatic, castration-resistant prostate cancer with a BRCA1, BRCA2, or ATM alteration and who had disease progression after treatment with a second-generation androgen-receptor pathway inhibitor (ARPI). We randomly assigned the patients in a 2:1 ratio to receive oral rucaparib (600 mg twice daily) or a physician's choice control (docetaxel or a second-generation ARPI [abiraterone acetate or enzalutamide]). The primary outcome was the median duration of imaging-based progression-free survival according to independent review. RESULTS: Of the 4855 patients who had undergone prescreening or screening, 270 were assigned to receive rucaparib and 135 to receive a control medication (intention-to-treat population); in the two groups, 201 patients and 101 patients, respectively, had a BRCA alteration. At 62 months, the duration of imaging-based progression-free survival was significantly longer in the rucaparib group than in the control group, both in the BRCA subgroup (median, 11.2 months and 6.4 months, respectively; hazard ratio, 0.50; 95% confidence interval [CI], 0.36 to 0.69) and in the intention-to-treat group (median, 10.2 months and 6.4 months, respectively; hazard ratio, 0.61; 95% CI, 0.47 to 0.80; P<0.001 for both comparisons). In an exploratory analysis in the ATM subgroup, the median duration of imaging-based progression-free survival was 8.1 months in the rucaparib group and 6.8 months in the control group (hazard ratio, 0.95; 95% CI, 0.59 to 1.52). The most frequent adverse events with rucaparib were fatigue and nausea. CONCLUSIONS: The duration of imaging-based progression-free survival was significantly longer with rucaparib than with a control medication among patients who had metastatic, castration-resistant prostate cancer with a BRCA alteration. (Funded by Clovis Oncology; TRITON3 ClinicalTrials.gov number, NCT02975934.).

Supportive care interventions for men with urological cancers: a scoping review.

PURPOSE: To identify supportive care interventions for men with urological cancers. METHODS: Experimental studies conducted among men with any urological cancer were eligible for inclusion. Academic Search Complete, CINAHL Plus with Full Text, MEDLINE, APA PsycArticles, APA PsycInfo, Social Sciences Full Text (H.W. Wilson), SocINDEX with Full Text, ERIC, Google Scholar and ClinicalTrials.gov were searched on 6 December 2022. No database limits were applied. The included studies were methodologically appraised. A narrative synthesis of the results was conducted. RESULTS: Thirty studies were included with 10 categories of interventions identified. Over 300 outcomes were measured, and more than 100 instruments were used. Multicomponent interventions generally led to positive changes in physiological outcomes like body mass index, as well as exercise tolerance and quality of life. This change, however, was not sustained in the long term. Cognitive-behavioural interventions significantly improved psychological symptoms but seldom physical symptoms. Telephone and web-based interventions showed great promise in improving outcomes like depression, positive affect, negative affect, perceived stress, spiritual wellbeing and fatigue. Findings from physical activity/exercise-based interventions were promising for both, physical and psychological outcomes. Rehabilitative interventions were associated with significant improvements in quality of life, urinary symptoms and psychological symptoms, albeit in the short term. Mixed results were reported for nurse-led interventions, family-based interventions and nutritional interventions. CONCLUSION: All but one study focused exclusively on prostate cancer. The included studies were significantly heterogeneous. Multicomponent, cognitive-behavioural, telephone and web-based, physical activity/exercise-based and rehabilitative interventions showed great promise in improving various outcomes. This improvement, however, was often short-lived.

Room to Improve: An Audit of In-Hospital End-of-Life Care for Oncology Patients in a Tertiary Cancer Centre in Ireland During the COVID-19 Pandemic.

The COVID-19 pandemic compounded isolation for patients through social distancing measures and staff shortages. We were concerned about the impact of COVID-19 on the quality of care provided at end-of-life in 2021 in a national cancer centre, and instigated the first ever review of the care of the dying. Quality of care was assessed retrospectively using a validated instrument developed by the United Kingdom's National Quality Board. Sixty-six patient deaths occurred in our cancer centre in 2021. The 'risk of dying' was documented in 65.2% of records. Palliative care services were involved in 77%, and pastoral care in 10.6%. What was important to the patient was documented in 24.2%. The 'quality-of-death' score was satisfactory for most but poor in 21.2%. Our study prompted change, including appointment of an end-of-life coordinator, development of a checklist to ensure comprehensive communication, expansion of the end-of-life committee to include junior doctors, and regular audit.

Mocetinostat for patients with previously treated, locally advanced/metastatic urothelial carcinoma and inactivating alterations of acetyltransferase genes.

BACKGROUND: The authors evaluated mocetinostat (a class I/IV histone deacetylase inhibitor) in patients with urothelial carcinoma harboring inactivating mutations or deletions in CREB binding protein [CREBBP] and/or E1A binding protein p300 [EP300] histone acetyltransferase genes in a single-arm, open-label phase 2 study. METHODS: Eligible patients with platinum-treated, advanced/metastatic disease received oral mocetinostat (at a dose of 70 mg 3 times per week [TIW] escalating to 90 mg TIW) in 28-day cycles in a 3-stage study (ClinicalTrials.gov identifier NCT02236195). The primary endpoint was the objective response rate. RESULTS: Genomic testing was feasible in 155 of 175 patients (89%). Qualifying tumor mutations were CREBBP (15%), EP300 (8%), and both CREBBP and EP300 (1%). A total of 17 patients were enrolled into stage 1 (the intent-to-treat population); no patients were enrolled in subsequent stages. One partial response was observed (11% [1 of 9 patients; the population that was evaluable for efficacy comprised 9 of the 15 planned patients]); activity was deemed insufficient to progress to stage 2 (null hypothesis: objective response rate of ≤15%). All patients experienced ≥1 adverse event, most commonly nausea (13 of 17 patients; 77%) and fatigue (12 of 17 patients; 71%). The median duration of treatment was 46 days; treatment interruptions (14 of 17 patients; 82%) and dose reductions (5 of 17 patients; 29%) were common. Mocetinostat exposure was lower than anticipated (dose-normalized maximum serum concentration [Cmax ] after TIW dosing of 0.2 ng/mL/mg). CONCLUSIONS: To the authors' knowledge, the current study represents the first clinical trial using genomic-based selection to identify patients with urothelial cancer who are likely to benefit from selective histone deacetylase inhibition. Mocetinostat was associated with significant toxicities that impacted drug exposure and may have contributed to modest clinical activity in these pretreated patients. The efficacy observed was considered insufficient to warrant further investigation of mocetinostat as a single agent in this setting.

The safety and efficacy of single-agent pemetrexed in platinum-resistant advanced urothelial carcinoma: a large single-institution experience.

BACKGROUND: Pemetrexed is a commonly used treatment for platinum-resistant advanced urothelial carcinoma (UC) based on objective response rates of 8% and 28% in two small phase II studies. To address the discrepancy in reported response rates and to assess efficacy and toxicity outside of a clinical trial setting, we performed a large retrospective analysis of pemetrexed use at Memorial Sloan Kettering Cancer Center. We also investigated candidate prognostic factors for overall survival in this setting to explore whether the neutrophil-lymphocyte ratio (NLR) had independent prognostic significance. PATIENTS AND METHODS: Patients receiving pemetrexed for platinum-resistant advanced UC between 2008 and 2013 were identified. The Response Evaluation Criteria in Solid Tumors (RECIST, version 1.1) were used to determine response rate. Kaplan-Meier and Cox regression analyses were used to examine the association of various factors with efficacy and survival outcomes. Hematologic toxicity and laboratory abnormalities were recorded. RESULTS: One hundred and twenty-nine patients were treated with pemetrexed. The objective response rate was 5% (95% confidence interval: 1%-9%), and the median duration of response was 8 months. Median progression-free survival (PFS) was 2.4 months, and the 6-month PFS rate was 14%. There was no significant difference in response rate by age, Eastern Cooperative Oncology Group (ECOG) performance status, or number of prior therapies. On multivariable analysis, ECOG performance status (p < .01), liver metastases (p = .02), and NLR (p < .01) had independent prognostic significance for overall survival. CONCLUSION: This 129-patient series is the largest reported data set describing pemetrexed use in advanced UC. Activity was modest, although discovery of molecular biomarkers predictive of response would be valuable to identify the small subset of patients who do gain significant benefit. Overall, the data highlight the urgent need to develop novel therapies for these patients.

DNA copy number analysis of metastatic urothelial carcinoma with comparison to primary tumors.

BACKGROUND: To date, there have been no reports characterizing the genome-wide somatic DNA chromosomal copy-number alteration landscape in metastatic urothelial carcinoma. We sought to characterize the DNA copy-number profile in a cohort of metastatic samples and compare them to a cohort of primary urothelial carcinoma samples in order to identify changes that are associated with progression from primary to metastatic disease. METHODS: Using molecular inversion probe array analysis we compared genome-wide chromosomal copy-number alterations between 30 metastatic and 29 primary UC samples. Whole transcriptome RNA-Seq analysis was also performed in primary and matched metastatic samples which was available for 9 patients. RESULTS: Based on a focused analysis of 32 genes in which alterations may be clinically actionable, there were significantly more amplifications/deletions in metastases (8.6% vs 4.5%, p < 0.001). In particular, there was a higher frequency of E2F3 amplification in metastases (30% vs 7%, p = 0.046). Paired primary and metastatic tissue was available for 11 patients and 3 of these had amplifications of potential clinical relevance in metastases that were not in the primary tumor including ERBB2, CDK4, CCND1, E2F3, and AKT1. The transcriptional activity of these amplifications was supported by RNA expression data. CONCLUSIONS: The discordance in alterations between primary and metastatic tissue may be of clinical relevance in the era of genomically directed precision cancer medicine.

A phase II trial of AS1411 (a novel nucleolin-targeted DNA aptamer) in metastatic renal cell carcinoma.

BACKGROUND: DNA aptamers represent a novel strategy in anti-cancer medicine. AS1411, a DNA aptamer targeting nucleolin (a protein which is overexpressed in many tumor types), was evaluated in patients with metastatic, clear-cell, renal cell carcinoma (RCC) who had failed treatment with ≥1 prior tyrosine kinase inhibitor. METHODS: In this phase II, single-arm study, AS1411 was administered at 40 mg/kg/day by continuous intravenous infusion on days 1-4 of a 28-day cycle, for two cycles. Primary endpoint was overall response rate; progression-free survival (PFS) and safety were secondary endpoints. RESULTS: 35 patients were enrolled and treated. One patient (2.9 %) had a response to treatment. The response was dramatic (84 % reduction in tumor burden by RECIST 1.0 criteria) and durable (patient remains free of progression 2 years after completing therapy). Whole exome sequencing of this patient's tumor revealed missense mutations in the mTOR and FGFR2 genes which is of interest because nucleolin is known to upregulate mTOR pathway activity by enhancing AKT1 mRNA translation. No other responses were seen. Thirty-four percent of patients had an AS1411-related adverse event, all of which were mild or moderate. CONCLUSIONS: AS1411 appears to have minimal activity in unselected patients with metastatic RCC. However, rare, dramatic and durable responses can be observed and toxicity is low. One patient in this study had an excellent response and was found to have FGFR2 and mTOR mutations which will be of interest in future efforts to discover and validate predictive biomarkers of response to nucleolin targeted compounds. DNA aptamers represent a novel way to target cancer cells at a molecular level and continue to be developed with a view to improving treatment and imaging in cancer medicine.

An evaluation of the utilisation of biosimilar monoclonal antibody drugs in Ireland and barriers to their usage.

BACKGROUND: While biologic drugs have demonstrated efficacy across a range of indications, patient access to these drugs is constrained due to their high cost. Biosimilars provide a means to increase patient access while reducing the financial burden. AIMS: The primary objective was to determine the current usage of biosimilar and reference trastuzumab and rituximab in four Irish hospitals. A secondary objective involved determining barriers to biosimilar usage. METHODS: This project involved a retrospective chart review to analyse the usage of reference and biosimilar versions of trastuzumab and rituximab. Additionally, a prospective cross-sectional study identified barriers to the usage of biosimilars via the distribution of a novel questionnaire to patients, pharmacists, doctors and students. RESULTS: The utilisation of biosimilar intravenous trastuzumab and rituximab ranged from 39 to 100%, and 0 to 89%, respectively. A total of n = 479 questionnaire responses were included. Biosimilar awareness was significantly lower among 'Doctors and Medical Students' (45.3%; 95% [CI, 33.8-57.3%]) compared to 'Pharmacists and Pharmacy Students' (97.1%; 95% [CI, 94-98.8%; comparison p < 0.001]). A significant majority of healthcare professionals agreed biosimilars should have consistent nomenclature (p < 0.001). A significant majority of patients (87.3%, 95% [CI, 81.3-92%; p < 0.001]) indicated that they would agree to commence using a biosimilar medicine. CONCLUSION: Biosimilar versions of trastuzumab and rituximab were in use to a variable extent. There remains a considerable opportunity to further increase the usage to maximise their potential benefits. A series of challenges were identified including reduced awareness among the medical profession and lack of clear nomenclature.

The impact of expanded access programs for systemic anticancer therapy in an Irish cancer centre.

BACKGROUND: Expanded access programs (EAPs) allow cancer patients with unmet clinical need to obtain access to pre-authorisation treatments. There is no standardised process for implementing these programs nationally, and real-world data on their impact is lacking. AIMS: This study aimed to evaluate the prevalence of such EAPs and their impact in a cancer centre. METHODS: Data relating to adult cancer patients treated via EAPs from 2011 to 2021 in three Cork university hospitals was collated. Descriptive statistics were employed to get an overview of the impact these programs currently have on cancer care provision. RESULTS: We identified 193 patients who accessed EAPs during the study period, availing of 33 separate drugs for a total of 50 different cancer indications. The prevalence of EAP usage was shown to have been trending upwards in recent years with a total of 189 programs being accessed throughout the period. Drugs provided were from a number of different anti-cancer drug classes, particularly targeted therapies (n = 18) and immune checkpoint inhibitors (n = 17). Cancers from a wide range of both solid and liquid tumour types were treated with EAP drugs, and patients treated were from across a broad spectrum of ages (26-82, SD 11.99). CONCLUSIONS: EAPs have an increasing role in accessing novel cancer therapies in our community and by extension nationally. Equity of EAP access would be facilitated by a national registry of available agents which we have established. Assessment of their benefits and toxicities would be enhanced by the requirement for a real-world database as a condition of EAP approval.

Actionable mutations in muscle-invasive bladder cancer.

PURPOSE OF REVIEW: Thirty-five percent of bladder cancer patients either present with or develop muscle-invasive disease. The current standard of care for these patients is neoadjuvant chemotherapy followed by radical cystoprostatectomy or combined chemoradiotherapy. Despite these therapies, approximately 50% of patients will relapse after definitive locoregional treatment and eventually succumb to their disease. RECENT FINDINGS: Therapies targeted at altered genetic pathways have proven efficacy in localized solid tumors including breast cancer, head and neck cancer and GIST. No such treatments have proven clinical benefit in bladder cancer, but targets under active investigation include HER2, epidermal growth factor receptors, fibroblast growth factor receptor 3, mTOR and others. Efforts are also underway to genetically define the subgroup of patients, which benefit from systemic platinum-based chemotherapy in this setting. SUMMARY: Ongoing clinical trials are investigating the role of treatments targeted at actionable genetic mutations in bladder cancer. The key to maximizing the potential benefit from this treatment approach will be the identification of predictive biomarkers of response, the identification of safe combinations which block multiple signaling molecules synchronously, and the availability of faster, cheaper genetic testing in the clinic.

Cost and public reimbursement of cancer medicines in the UK and the Republic of Ireland.

INTRODUCTION/AIMS: There are disparities in the availability of systemic anticancer therapies (SACTs) globally. We set out to investigate the cost and reimbursement of SACTs in the United Kingdom (UK) and the Republic of Ireland (ROI) in conjunction with efficacy and licensing authority decisions in the United States (US) and the European Union (EU). METHODS: We sought data pertaining to licensing in the EU, reimbursement in ROI/UK and cost/efficacy of SACTs licensed by the Food and Drug Administration (FDA) between January 2015 and May 2021. Independent samples t tests, chi-square test and Pearson's correlation were used for statistical analysis. RESULTS: We identified that the majority of FDA-approved regimens are licensed by the European Medicines Agency (EMA) (n = 91, 67.9%). However, only a minority of these are currently reimbursed in the UK (n = 60, 45%) or the ROI (n = 28, 21%) as of the 1st of May 2021. In addition, only a minority of regimens have demonstrated a statistically significant OS benefit (n = 54, 40%). There was no association between cost of regimens and either the presence (t = 0.846, p = 0.40) or duration of OS benefit (t = - 0.84, p = 0.64). CONCLUSIONS: Our study highlights that many licensed systemic anticancer treatments are not currently reimbursed in ROI/UK. The high cost of these medicines is independent of the presence of an OS benefit. Collaboration between regulatory agencies, governments and industry partners is needed to ensure health expenditure is directed towards the most effective treatments.

A pilot project investigating the use of ONCOpatient®-An electronic patient-reported outcomes app for oncology patients.

Purpose: To investigate the feasibility of implementing a remote patient monitoring system using an electronic patient-reported outcomes (ePROs) platform in a tertiary cancer center in the Republic of Ireland. Methods: Patients receiving oral chemotherapy and oncology clinicians were invited to participate in the study. Patients were asked to submit weekly symptom questionnaires through an ePRO mobile phone application (app)-ONCOpatient®. Clinical staff were invited to use the ONCOpatient® clinician interface. After 8 weeks all participants submitted evaluation questionnaires. Results: Thirteen patients and five staff were enrolled in the study. The majority of patients were female (85%) with a median age of 48 years (range 22-73). Most (92%) were enrolled over telephone requiring on average 16 minutes. Compliance with the weekly assessments was 91%. Alerts were triggered by 40% of patients who then required phone calls to aid with symptom management. At the end of study, 87% of patients reported they would use the app frequently, 75% reported that the platform met their expectations, and 25% that it exceeded their expectations. Similarly, 100% of staff reported they would use the app frequently, 60% reported that it met their expectations, and 40% that it exceeded their expectations. Conclusions: Our pilot study showed that it is feasible to implement ePRO platforms in the Irish clinical setting. Small sample bias was recognized as a limitation, and we plan to confirm our findings on a larger cohort of patients. In the next phase we will integrate wearables including remote blood pressure monitoring.

Real-world outcomes and toxicity of adjuvant chemotherapy in NSCLC: a single-center experience.

Aim: Adjuvant chemotherapy in NSCLC is associated with modest benefits and significant toxicity. We sought to evaluate the toxicity of adjuvant chemotherapy and disease-specific outcomes in a real-world population. Methods: We performed a retrospective analysis of patients undergoing adjuvant chemotherapy for NSCLC in an Irish center over a 7-year period. We described treatment-associated toxicity, recurrence-free survival and overall survival. Results: 62 patients underwent adjuvant chemotherapy. Treatment-associated hospitalisation occurred in 29% of patients. Relapse was recorded in 56% of patients and median recurrence-free survival was 27 months. Conclusion: High rates of disease recurrence and treatment-associated morbidity were observed in patients receiving adjuvant chemotherapy for NSCLC. Novel therapeutic strategies are required to improve outcomes in this population.

Early NSCLC is primarily managed with lung cancer surgery. Chemotherapy is offered to some patients with early NSCLC after surgery depending on the size of the tumor and lymph node involvement. The benefit of post-surgery (adjuvant) chemotherapy in reducing the chance of cancer recurrence has been shown to be relatively small in previous studies. Large studies of post-surgery chemotherapy in NSCLC have included limited numbers of older patients, and patients with significant medical issues. This study looked to evaluate the safety and treatment-associated side effects of adjuvant chemotherapy in a group of patients more reflective of everyday clinical practice, and to assess the rates of cancer recurrence in these patients. In our study of 62 patients who underwent adjuvant chemotherapy for NSCLC, nearly 1 in 3 patients required hospital admission due to treatment-associated side effects. Almost 40% of patients experienced significant blood test abnormalities (including anaemia, reduced platelets, and reduced white blood cells). Approximately 1 in 4 patients required a reduction in the doses of their treatment due to treatment-associated side effects. More than half of the patients in our study experienced a recurrence of their cancer. Our study demonstrates the significant side effects associated with adjuvant chemotherapy in NSCLC and highlights the need for better-tolerated treatment strategies to reduce cancer recurrence in early NSCLC.

Rucaparib for the Treatment of Metastatic Castration-resistant Prostate Cancer Associated with a DNA Damage Repair Gene Alteration: Final Results from the Phase 2 TRITON2 Study.

BACKGROUND: Initial TRITON2 (NCT02952534) results demonstrated the efficacy of rucaparib 600 mg BID in patients with metastatic castration-resistant prostate cancer (mCRPC) associated with a BRCA1 or BRCA2 (BRCA) or other DNA damage repair (DDR) gene alteration. OBJECTIVE: To present the final data from TRITON2. DESIGN, SETTING, AND PARTICIPANTS: TRITON2 enrolled patients with mCRPC who had progressed on one or two lines of next-generation androgen receptor-directed therapy and one taxane-based chemotherapy. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The primary endpoint was objective response rate (ORR; as per the modified Response Evaluation Criteria in Solid Tumor Version 1.1/Prostate Cancer Clinical Trials Working Group 3 criteria in patients with measurable disease by independent radiology review [IRR]); prostate-specific antigen (PSA) response rate (≥50% decrease from baseline [PSA50]) was a key secondary endpoint. RESULTS AND LIMITATIONS: As of July 27, 2021 (study closure), TRITON2 had enrolled 277 patients, grouped by mutated gene: BRCA (n = 172), ATM (n = 59), CDK12 (n = 15), CHEK2 (n = 7), PALB2 (n = 11), or other DDR gene (Other; n = 13). ORR by IRR was 46% (37/81) in the BRCA subgroup (95% confidence interval [CI], 35-57%), 100% (4/4) in the PALB2 subgroup (95% CI, 40-100%), and 25% (3/12) in the Other subgroup (95% CI, 5.5-57%). No patients within the ATM, CDK12, or CHEK2 subgroups had an objective response by IRR. PSA50 response rates (95% CI) in the BRCA, PALB2, ATM, CDK12, CHEK2, and Other subgroups were 53% (46-61%), 55% (23-83%), 3.4% (0.4-12), 6.7% (0.2-32%), 14% (0.4-58%), and 23% (5.0-54%), respectively. CONCLUSIONS: The final TRITON2 results confirm the clinical benefit and manageable safety profile of rucaparib in patients with mCRPC, including those with an alteration in BRCA or select non-BRCA DDR gene. PATIENT SUMMARY: Almost half of TRITON2 patients with BRCA-mutated metastatic castration-resistant prostate cancer had a complete or partial tumor size reduction with rucaparib; clinical benefits were also observed with other DNA damage repair gene alterations.

Prostate cancer: germline prediction for a commonly variable malignancy.

UNLABELLED: What's known on the subject? and What does the study add? Prostate cancer is a heterogeneous disease and biomarkers to predict its incidence and subsequent clinical behaviour are needed to tailor screening, prevention and therapeutic strategies. Rare mutations in genes such as BRCA1, BRCA2 and HOXB13 can affect prostate cancer incidence and/or clinical behaviour. Genome wide association studies (GWAS) have identified more common genetic variations that explain an estimated 20% of familial prostate cancer risk. In this review, we focus on the potential of germline genetic variation to provide biomarkers for prostate cancer screening, prevention and management. We discuss how germline genetics may have a role in treatment selection if reliable pharmacogenetic predictors of efficacy and toxicity can be identified. We have outlined possible mechanisms for including germline investigation in future prostate cancer clinical trials. OBJECTIVES: • Prostate cancer is a heterogeneous disease and biomarkers to predict its incidence and subsequent clinical behaviour are needed to tailor screening, prevention and therapeutic strategies. • In this review we focus on the potential of germline genetic variation to provide these biomarkers. METHODS: • We review the published literature on germline genetics in prostate cancer and examine the possibility of including germline genetic biomarkers in future prostate cancer clinical trials. RESULTS: • Rare mutations in genes such as BRCA1, BRCA2 and HOXB13 can affect prostate cancer incidence and/or clinical behaviour. • Genome-wide association studies (GWAS) have identified more common genetic variations that explain an estimated 20% of familial prostate cancer risk. • Germline genetics may have a role in treatment selection, if reliable pharmacogenetic predictors of efficacy and toxicity can be identified. CONCLUSION: • This rapidly emerging area of prostate cancer research may provide answers to current clinical conundrums in the prostate cancer treatment paradigm. We have outlined possible mechanisms for including germline investigation in future prostate cancer clinical trial design.

Response to Rucaparib in BRCA-Mutant Metastatic Castration-Resistant Prostate Cancer Identified by Genomic Testing in the TRITON2 Study.

PURPOSE: The PARP inhibitor rucaparib is approved in the United States for patients with metastatic castration-resistant prostate cancer (mCRPC) and a deleterious germline and/or somatic BRCA1 or BRCA2 (BRCA) alteration. While sequencing of tumor tissue is considered the standard for identifying patients with BRCA alterations (BRCA+), plasma profiling may provide a minimally invasive option to select patients for rucaparib treatment. Here, we report clinical efficacy in patients with BRCA+ mCRPC identified through central plasma, central tissue, or local genomic testing and enrolled in TRITON2. PATIENTS AND METHODS: Patients had progressed after next-generation androgen receptor-directed and taxane-based therapies for mCRPC and had BRCA alterations identified by central sequencing of plasma and/or tissue samples or local genomic testing. Concordance of plasma/tissue BRCA status and objective response rate and prostate-specific antigen (PSA) response rates were summarized. RESULTS: TRITON2 enrolled 115 patients with BRCA+ identified by central plasma (n = 34), central tissue (n = 37), or local (n = 44) testing. Plasma/tissue concordance was determined in 38 patients with paired samples and was 47% in 19 patients with a somatic BRCA alteration. No statistically significant differences were observed between objective and PSA response rates to rucaparib across the 3 assay groups. Patients unable to provide tissue samples and tested solely by plasma assay responded at rates no different from patients identified as BRCA+ by tissue testing. CONCLUSIONS: Plasma, tissue, and local testing of mCRPC patients can be used to identify men with BRCA+ mCRPC who can benefit from treatment with the PARP inhibitor rucaparib.

Rucaparib in Men With Metastatic Castration-Resistant Prostate Cancer Harboring a BRCA1 or BRCA2 Gene Alteration.

PURPOSE: BRCA1 or BRCA2 (BRCA) alterations are common in men with metastatic castration-resistant prostate cancer (mCRPC) and may confer sensitivity to poly(ADP-ribose) polymerase inhibitors. We present results from patients with mCRPC associated with a BRCA alteration treated with rucaparib 600 mg twice daily in the phase II TRITON2 study. METHODS: We enrolled patients who progressed after one to two lines of next-generation androgen receptor-directed therapy and one taxane-based chemotherapy for mCRPC. Efficacy and safety populations included patients with a deleterious BRCA alteration who received ≥ 1 dose of rucaparib. Key efficacy end points were objective response rate (ORR; per RECIST/Prostate Cancer Clinical Trials Working Group 3 in patients with measurable disease as assessed by blinded, independent radiology review and by investigators) and locally assessed prostate-specific antigen (PSA) response (≥ 50% decrease from baseline) rate. RESULTS: Efficacy and safety populations included 115 patients with a BRCA alteration with or without measurable disease. Confirmed ORRs per independent radiology review and investigator assessment were 43.5% (95% CI, 31.0% to 56.7%; 27 of 62 patients) and 50.8% (95% CI, 38.1% to 63.4%; 33 of 65 patients), respectively. The confirmed PSA response rate was 54.8% (95% CI, 45.2% to 64.1%; 63 of 115 patients). ORRs were similar for patients with a germline or somatic BRCA alteration and for patients with a BRCA1 or BRCA2 alteration, while a higher PSA response rate was observed in patients with a BRCA2 alteration. The most frequent grade ≥ 3 treatment-emergent adverse event was anemia (25.2%; 29 of 115 patients). CONCLUSION: Rucaparib has antitumor activity in patients with mCRPC and a deleterious BRCA alteration, but with a manageable safety profile consistent with that reported in other solid tumor types.