Differences in Trial and Real-world Populations in the Dutch Castration-resistant Prostate Cancer Registry

Impact of Comorbidities and Drug Interactions in Patients With Metastatic Castration-Resistant Prostate Cancer Receiving Androgen Receptor Pathway Inhibitors

PURPOSE

Androgen receptor pathway inhibitors (ARPIs) are widely prescribed in metastatic castration-resistant prostate cancer (mCRPC). Real-world frequencies and potential impacts of comorbidities and concomitant medication (conmed) interactions with ARPIs are not well described.

METHODS

Patients receiving ARPIs for mCRPC were identified from the electronic Prostate Cancer Australian Database (ePAD). Demographics, clinicopathologic characteristics, and outcome data were extracted. Conmeds and comorbidities were collected from medical records. Potential interacting comorbidities were defined from trial and post-trial data. Clinically significant drug-drug interactions (DDIs) were identified using UpToDate Lexicomp and Stockley's databases. Patient characteristics, comorbidity interactions, DDIs, and outcomes were analyzed.

RESULTS

Two hundred thirty-five patients received first- or second-line ARPIs for mCRPC from 2012 to 2021, with a median follow-up of 27 months. One hundred sixteen received abiraterone acetate (AAP) and 135 received enzalutamide (ENZ). The median age was 74 years, and the median number of conmeds was 4. Clinically significant DDIs occurred in 55 (47%) AAP patients and 90 (67%) ENZ patients. Only 5% of DDIs were predicted to affect ARPI pharmacokinetics (PK) or pharmacodynamics, whereas 95% were predicted to impact conmed PK or increase toxicity risk. In patients receiving ENZ, DDIs were associated with lower PSA50 (50% v 74%, P = .04) and poorer overall survival (28 v 45 months, P = .04), although statistical significance was not maintained on multivariate analysis. No significant survival differences were seen with DDIs in patients receiving AAP. Potential interactions between comorbidities and ARPI were present in 72% on AAP and 14% on ENZ with no significant associated survival differences.

CONCLUSION

DDIs and drug-comorbidity interactions in real-world patients receiving ARPIs for mCRPC are common and may affect outcomes. Ongoing clinician education regarding DDIs is necessary to optimize patient outcomes.

Harnessing the Potential of Real-World Evidence in the Treatment of Colorectal Cancer: Where Do We Stand?

OPINION STATEMENT

Treatment guidelines for colorectal cancer (CRC) are primarily based on the results of randomized clinical trials (RCTs), the gold standard methodology to evaluate safety and efficacy of oncological treatments. However, generalizability of trial results is often limited due to stringent eligibility criteria, underrepresentation of specific populations, and more heterogeneity in clinical practice. This may result in an efficacy-effectiveness gap and uncertainty regarding meaningful benefit versus treatment harm. Meanwhile, conduct of traditional RCTs has become increasingly challenging due to identification of a growing number of (small) molecular subtypes. These challenges-combined with the digitalization of health records-have led to growing interest in use of real-world data (RWD) to complement evidence from RCTs. RWD is used to evaluate epidemiological trends, quality of care, treatment effectiveness, long-term (rare) safety, and quality of life (QoL) measures. In addition, RWD is increasingly considered in decision-making by clinicians, regulators, and payers. In this narrative review, we elaborate on these applications in CRC, and provide illustrative examples. As long as the quality of RWD is safeguarded, ongoing developments, such as common data models, federated learning, and predictive modelling, will further unfold its potential. First, whenever possible, we recommend conducting pragmatic trials, such as registry-based RCTs, to optimize generalizability and answer clinical questions that are not addressed in registrational trials. Second, we argue that marketing approval should be conditional for patients who would have been ineligible for the registrational trial, awaiting planned (non) randomized evaluation of outcomes in the real world. Third, high-quality effectiveness results should be incorporated in treatment guidelines to aid in patient counseling. We believe that a coordinated effort from all stakeholders is essential to improve the quality of RWD, create a learning healthcare system with optimal use of trials and real-world evidence (RWE), and ultimately ensure personalized care for every CRC patient.

Generating and using real-world data: A worthwhile uphill battle

The precision oncology paradigm challenges the feasibility and data generalizability of traditional clinical trials. Consequently, an unmet need exists for practical approaches to test many subgroups, evaluate real-world drug value, and gather comprehensive, accessible datasets to validate novel biomarkers. Real-world data (RWD) are increasingly recognized to have the potential to fill this gap in research methodology. Established applications of RWD include informing disease epidemiology, pharmacovigilance, and healthcare quality assessment. Currently, concerns regarding RWD quality and comprehensiveness, privacy, and biases hamper their broader application. Nonetheless, RWD may play a pivotal role in supplementing clinical trials, enabling conditional reimbursement and accelerated drug access, and innovating trial conduct. Moreover, purpose-built RWD repositories may support the extension or refinement of drug indications and facilitate the discovery and validation of new biomarkers. This perspective explores the potential of leveraging RWD to advance oncology, highlights its benefits and challenges, and suggests a path forward in this evolving field.

Efficacy-effectiveness gaps in oncology: Looking beyond survival

The efficacy-effectiveness (EE) gap describes the differences in survival seen in clinical trials and routine clinical practice, where patients in real-world practice often have inferior outcomes compared to trial populations. However, EE gaps may exist beyond survival outcomes, including gaps in quality of life, toxicity, cost-effectiveness, and patient time, and these EE gaps should also influence patient and clinician treatment decisions. Failure to clearly acknowledge these EE gaps may cause patients, clinicians, and health care systems to have unrealistic expectations of the benefits of therapy across a range of important clinical and economic domains. In this commentary, the authors review the evidence supporting the existence of EE gaps in quality of life, time toxicity, cost and toxicities, and urge for further research into this important topic.

Time trends in systemic treatment for patients with metastatic prostate cancer: a national cohort study

BACKGROUND

Several new systemic treatments for primary metastatic prostate cancer patients (mPCa) were introduced in the last decade for both hormone-sensitive (mHSPC) and castration-resistant prostate cancer (mCRPC). However, little is known about the introduction of these treatments in clinical practice. In this national cohort study, we described users and non-users of systemic treatment beyond androgen deprivation therapy (ADT). We also explored whether there was a shift in treatment patterns after the introduction of Docetaxel for mHSPC patients.

MATERIALS AND METHODS

All patients registered in the Cancer Registry of Norway with mPCa diagnosed in 2010-18 were included. Data on systemic therapy (Docetaxel, Abiraterone, Enzalutamide, Cabazitaxel, and Radium-223) were provided from the Norwegian Prescription Database, the Norwegian Patient Registry, and the Norwegian Control and Payment of Health Reimbursement Database. Descriptive results about patient and disease characteristics were presented using frequencies and proportions, means and standard deviations, or medians and interquartile ranges.

RESULTS

Of the 2770 patients included in this study, 48% received systemic treatment beyond ADT. The proportion of patients receiving systemic treatment increased during the study period. Systemic treatment users were younger, in better general condition, and had more aggressive tumors than non-users. A treatment shift was observed after 2015, with 48% of patients receiving systemic treatment (mainly Docetaxel) in the mHSPC phase compared to 4% of those diagnosed 2010-14. No significant treatment differences were observed across health regions.

CONCLUSIONS

An increasing proportion of patients received systemic treatment during the period 2010-18. However, less than 50% of patients in our study received systemic treatment. In accordance with updated guidelines, Docetaxel was introduced after 2015 with an increasing proportion of patients receiving systemic treatment as mHSPC. Further studies should address the disease course and treatment given to patients who do not receive systemic treatment.

Assessing real-world representativeness of prospective registry cohorts in oncology: insights from patients with esophagogastric cancer

OBJECTIVES

This study aimed to explore the real-world representativeness of a prospective registry cohort with active accrual in oncology, applying a representativeness metric that is novel to health care.

STUDY DESIGN AND SETTING

We used data from the Prospective Observational Cohort Study of Esophageal-Gastric Cancer Patients (POCOP) registry and from the population-based Netherlands Cancer Registry (NCR). We used Representativeness-indicators (R-indicators) and overall survival to investigate the degree to which the POCOP cohort and clinically relevant subgroups were a representative sample compared to the NCR database. Calibration using inverse propensity score weighting was applied to correct differences between POCOP and NCR.

RESULTS

The R-indicator of the entire POCOP registry was 0.72 95% confidence interval [0.71, 0.73]. Representativeness of palliative patients was higher than that of potentially curable patients (R-indicator 0.88 [0.85, 0.90] and 0.70 [0.68, 0.71], respectively). Stratification to clinically relevant subgroups based on treatment resulted in higher R-indicators of the respective subgroups. Both after stratification and calibration weighting survival estimates in the POCOP registry were more similar to that in the NCR population.

CONCLUSION

This study demonstrated the assessment of real-world representativeness of patients who participated in a prospective registry cohort and showed that real-world representativeness improved when the variability in treatment was accounted for.

Reliability and Efficiency of the CAPRI-3 Metastatic Prostate Cancer Registry Driven by Artificial Intelligence

BACKGROUND

Manual data collection is still the gold standard for disease-specific patient registries. However, CAPRI-3 uses text mining (an artificial intelligence (AI) technology) for patient identification and data collection. The aim of this study is to demonstrate the reliability and efficiency of this AI-driven approach.

METHODS

CAPRI-3 is an observational retrospective multicenter cohort registry on metastatic prostate cancer. We tested the patient-identification algorithm and automated data extraction through manual validation of the same patients in two pilots in 2019 and 2022.

RESULTS

Pilot one identified 2030 patients and pilot two 9464 patients. The negative predictive value of the algorithm was maximized to prevent false exclusions and reached 94.8%. The completeness and accuracy of the automated data extraction were 92.3% or higher, except for date fields and inaccessible data (images/pdf) (10-88.9%). Additional manual quality control took over 3 h less time per patient than the original fully manual CAPRI registry (105 vs. 300 min).

CONCLUSIONS

The CAPRI-3 patient-identification algorithm is a sound replacement for excluding ineligible candidates. The AI-driven data extraction is largely accurate and complete, but manual quality control is needed for less reliable and inaccessible data. Overall, the AI-driven approach of the CAPRI-3 registry is reliable and timesaving.

How to create value with constrained budgets in oncological care? A narrative review

INTRODUCTION

As a result of an increasing focus on patient-centered care within oncology and more pressure on the sustainability of health-care systems, the discussion on what exactly constitutes value re-appears. Policymakers seek to improve patient values; however, funding all values is not sustainable.

AREAS COVERED

We collect available evidence from scientific literature and reflect on the concept of value, the possible incorporation of a wide spectrum of values in reimbursement decisions, and alternative strategies to increase value in oncological care.

EXPERT OPINION

We state that value holds many different aspects. For reimbursement decisions, we argue that it is simply not feasible to incorporate all patient values because of the need for efficient resource allocation. We argue that we should shift the value debate from the individual perspective of patients to creating value for the cancer population at large. The different strategies we address are as follows: (1) shared decision-making; (2) biomarkers and molecular diagnostics; (3) appropriate evaluation, payment and use of drugs; (4) supportive care; (5) cancer prevention and screening; (6) monitoring late effect; (7) concentration of care and oncological networking; and (8) management of comorbidities. Important preconditions to support these strategies are strategic planning, consistent cancer policies and data availability.

Role of multidisciplinary team meetings in implementation of chemohormonal therapy in metastatic prostate cancer in daily practice

BACKGROUND

The recommended treatment for a subset of patients with metastatic prostate cancer (mPC) changed from androgen deprivation therapy (ADT) to combinations with chemotherapy such as docetaxel. Implementation of new evidence from trials is however complex and challenging. We investigated the effect of multidisciplinary team meetings (MDTs) on adopting the newest emerging combination therapy in patients with mPC and assessed the overall survival of chemohormonal therapy in a real-world setting.

METHODS

All mPC patients diagnosed between October 2015 and April 2016 in the Netherlands were identified from the population-based Netherlands Cancer Registry (n = 962). Logistic regression analyses were performed to examine the role of patient- and tumor characteristics, with special emphasis on MDTs, on receiving chemohormonal therapy versus ADT monotherapy. Kaplan-Meier survival curves were used to assess overall survival (OS).

RESULTS

As many patients received ADT monotherapy as chemohormonal therapy (both n = 452). Being discussed in a MDT as patient, younger age, less comorbidities, a better performance status and high-volume disease were significantly associated with receiving chemohormonal therapy compared to ADT monotherapy. After adjustment for these factors, the presence of a MDT was independently associated with the administration of chemohormonal therapy (OR 2.77, 95% CI 1.68-4.59). The 2-year OS was 82.1% (95% CI: 78.5-85.6%) for patients receiving chemohormonal therapy and 59.9% (95% CI: 55.4-64.4%) for patients receiving ADT monotherapy.

CONCLUSION

Being discussed in a MDT is independently associated with the administration of chemohormonal therapy in this group of patients with mPC. This supports the hypothesis that implementation of innovative treatment options is facilitated by an organizational structure with MDTs.

Incidence and survival of castration-resistant prostate cancer patients with visceral metastases: results from the Dutch CAPRI-registry

BACKGROUND

The objective of this real-world population study is to investigate incidence and treatment of visceral metastases (VMs) in castration resistant prostate cancer (CRPC) patients and their survival.

METHODS

CRPC-patients in the CAPRI-registry between 2010 and 2016 were included in the analyses and followed till 2017. Outcomes were proportion of patients radiologically screened for VMs and proportion of patients with VMs at CRPC-diagnosis and at the start of every treatment line. Groups have been created based on location of VMs (lung, liver, or both) at date of first VM diagnosis. The outcome for these groups was overall survival (OS). Statistics included descriptive analyses, Kaplan-Meier method, and Cox proportional hazard regression analysis for survival analyses.

RESULTS

Of 3602 patients from the CAPRI registry, 457 patients (12.7%) were diagnosed with VMs during follow-up: 230 patients with liver, 161 with lung, and 66 with both liver and lung metastases. The proportion of patients radiologically screened for VMs increased per treatment line as did the occurrence rate of VMs. However, 80% of patients at CRPC diagnosis to 40% in the 6th line were not screened for VMs at the start of a systemic treatment. Median OS was 8.6 months for patients with liver, 18.3 with lung and 10.9 with both liver and lung metastases (p < 0.001) from date of first VM diagnosis. After correction for prognostic factors patients with lung metastases had significantly better OS than patients with liver metastases (HR 0.650, p = 0.001).

CONCLUSION

This real-world analysis showed that despite the increased rate of radiological staging during follow-up, still 80% to 40% of the patients (CRPC diagnosis to 6th treatment line respectively) were not screened for VMs at the start of a systemic treatment. VMs and location of VMs are key prognostic patient characteristics, impacts survival and have implications for treatment decisions, so routine staging of CRPC-patients is warranted.

CLINICAL TRIAL IDENTIFICATION

The CAPRI study is registered in the Dutch Trial Registry as NL3440 (NTR3591).

Treatments for Metastatic Hormone-sensitive Prostate Cancer: Systematic Review, Network Meta-analysis, and Benefit-harm assessment

CONTEXT

Multiple treatments for metastatic, hormone-sensitive prostate cancer (mHSPC) are available, but their effects on health-related quality of life (HRQoL) and benefit-harm balance remain unclear.

OBJECTIVE

To assess clinical effectiveness regarding survival and HRQoL, safety, and benefit-harm balance of mHSPC treatments.

EVIDENCE ACQUISITION

We searched MEDLINE, EMBASE, CENTRAL, and ClinicalTrials.gov until March 1, 2022. Randomized controlled trials (RCTs) comparing docetaxel, abiraterone, enzalutamide, apalutamide, darolutamide, and radiotherapy combined with androgen deprivation therapy (ADT) mutually or with ADT alone were eligible. Three reviewers independently performed screening, data extraction, and risk of bias assessment in duplicate.

EVIDENCE SYNTHESIS

Across ten RCTs, we found relevant survival benefits for ADT + docetaxel (high certainty according to the Grading of Recommendations, Assessment, Development and Evaluation [GRADE]), ADT + abiraterone (moderate certainty), ADT + enzalutamide (low certainty), ADT + apalutamide (high certainty), and ADT + docetaxel + darolutamide (high certainty) compared with ADT alone. ADT + radiotherapy appeared effective only in low-volume de novo mHSPC. We found a short-term HRQoL decrease lasting 3-6 mo for ADT + docetaxel (moderate certainty) and a potential HRQoL benefit for ADT + abiraterone up to 24 mo of follow-up (moderate certainty) compared with ADT alone. There was no difference in HRQoL for ADT + enzalutamide, ADT + apalutamide, or ADT + radiotherapy over ADT alone (low-high certainty). Grade 3-5 adverse effect rates were increased with all systemic combination treatments. A benefit-harm assessment showed high probabilities (>60%) for a net clinical benefit with ADT + abiraterone, ADT + enzalutamide, and ADT + apalutamide, while ADT + docetaxel and ADT + docetaxel + darolutamide appeared unlikely (<40%) to be beneficial.

CONCLUSIONS

Despite substantial survival benefits, no systemic combination treatment showed a clear HRQoL improvement compared with ADT alone. We found evidence for a short-term HRQoL decline with ADT + docetaxel and a higher net clinical benefit with ADT + abiraterone, ADT + apalutamide and ADT + enzalutamide. While individualized decision-making remains important and economic factors need to be considered, the evidence may support a general preference for the combination of ADT with androgen receptor axis-targeted therapies over docetaxel-containing strategies.

PATIENT SUMMARY

We assessed different combination treatments for metastatic hormone-sensitive prostate cancer. While survival was better with all systemic combination treatments, there was no clear improvement in health-related quality of life compared with androgen deprivation therapy alone. Novel hormonal combination treatments had a more favorable benefit-harm balance than combination treatments that include chemotherapy.

Modeling Disease Trajectories for Castration-resistant Prostate Cancer Using Nationwide Population-based Data

Background

Little is known about disease trajectories for men with castration-resistant prostate cancer (CRPC).

Objective

To create a state transition model that estimates time spent in the CRPC state and its outcomes.

Design, setting, and participants

The model was generated using population-based prostate-specific antigen data from 40% of the Swedish male population, which were linked to nationwide population-based databases. We compared the observed and predicted cumulative incidence of transitions to and from the CRPC state.

Outcome measurements and statistical analysis

We measured time spent in the CRPC state and the proportion of men who died of prostate cancer during follow-up by CRPC risk category.

Results and limitations

Time spent in the CRPC state varied from 1.1 yr for the highest risk category to 3.9 yr for the lowest risk category. The proportion of men who died from prostate cancer within 10 yr ranged from 93% for the highest risk category to 54% for the lowest. There was good agreement between the model estimates and observed data.

Conclusions

There is large variation in the time spent in the CRPC state, varying from 1 yr to 4 yr according to risk category.

Patient summary

It is possible to accurately estimate the disease trajectory and duration for men with castration-resistant prostate cancer.

Talazoparib, a Poly(ADP-ribose) Polymerase Inhibitor, for Metastatic Castration-resistant Prostate Cancer and DNA Damage Response Alterations: TALAPRO-1 Safety Analyses

BACKGROUND

The phase II TALAPRO-1 study (NCT03148795) demonstrated durable antitumor activity in men with heavily pretreated metastatic castration-resistant prostate cancer (mCRPC). Here, we detail the safety profile of talazoparib.

PATIENTS AND METHODS

Men received talazoparib 1 mg/day (moderate renal impairment 0.75 mg/day) orally until radiographic progression, unacceptable toxicity, investigator decision, consent withdrawal, or death. Adverse events (AEs) were evaluated: incidence, severity, timing, duration, potential overlap of selected AEs, dose modifications/discontinuations due to AEs, and new clinically significant changes in laboratory values and vital signs.

RESULTS

In the safety population (N = 127; median age 69.0 years), 95.3% (121/127) experienced all-cause treatment-emergent adverse events (TEAEs). Most common were anemia (48.8% [62/127]), nausea (33.1% [42/127]), decreased appetite (28.3% [36/127]), and asthenia (23.6% [30/127]). Nonhematologic TEAEs were generally grades 1 and 2. No grade 5 TEAEs or deaths were treatment-related. Hematologic TEAEs typically occurred during the first 4-5 months of treatment. The median duration of grade 3-4 anemia, neutropenia, and thrombocytopenia was limited to 7-12 days. No grade 4 events of anemia or neutropenia occurred. Neither BRCA status nor alteration origin significantly impacted the safety profile. The median (range) treatment duration was 6.1 (0.4-24.9) months; treatment duration did not impact the incidence of anemia. Only 3 of the 15 (11.8% [15/127]) permanent treatment discontinuations were due to hematologic TEAEs (thrombocytopenia 1.6% [2/127]; leukopenia 0.8% [1/127]).

CONCLUSION

Common TEAEs associated with talazoparib could be managed through dose modifications/supportive care. Demonstrated efficacy and a manageable safety profile support continued evaluation of talazoparib in mCRPC.

CLINICALTRIALS.GOV IDENTIFIER

NCT03148795.

Impact of molecular tumour board discussion on targeted therapy allocation in advanced prostate cancer

BACKGROUND

Molecular tumour boards (MTB) optimally match oncological therapies to patients with genetic aberrations. Prostate cancer (PCa) is underrepresented in these MTB discussions. This study describes the impact of routine genetic profiling and MTB referral on the outcome of PCa patients in a tertiary referral centre.

METHODS

All PCa patients that received next-generation sequencing results and/or were discussed at an MTB between Jan 1, 2017 and Jan 1, 2020 were included. Genetically matched therapies (GMT) in clinical trials or compassionate use were linked to actionable alterations. Response to these agents was retrospectively evaluated.

RESULTS

Out of the 277 genetically profiled PCa patients, 215 (78%) were discussed in at least one MTB meeting. A GMT was recommended to 102 patients (47%), of which 63 patients (62%) initiated the GMT. The most recommended therapies were PARP inhibitors (n = 74), programmed death-(ligand) 1 inhibitors (n = 21) and tyrosine kinase inhibitors (n = 19). Once started, 41.3% had a PFS of ≥6 months, 43.5% a PSA decline ≥50% and 38.5% an objective radiographic response.

CONCLUSION

Recommendation for a GMT is achieved in almost half of the patients with advanced prostate cancer, with GMT initiation leading to durable responses in over 40% of patients. These data justify routine referral of selected PCa patients to MTB's.

Being Transparent About Brilliant Failures: An Attempt to Use Real-World Data in a Disease Model for Patients with Castration-Resistant Prostate Cancer

BACKGROUND

Real-world disease models spanning multiple treatment lines can provide insight into the (cost) effectiveness of treatment sequences in clinical practice.

OBJECTIVE

Our objective was to explore whether a disease model based solely on real-world data (RWD) could be used to estimate the effectiveness of treatments for patients with castration-resistant prostate cancer (CRPC) that could then be suitably used in a cost-effectiveness analysis.

METHODS

We developed a patient-level simulation model using patient-level data from the Dutch CAPRI registry as input parameters. Time to event (TTE) and overall survival (OS) were estimated with multivariate regression models, and type of event (i.e., next treatment or death) was estimated with multivariate logistic regression models. To test internal validity, TTE and OS from the simulation model were compared with the observed outcomes in the registry.

RESULTS

Although patient characteristics and survival outcomes of the simulated data were comparable to those in the observed data (median OS 20.6 vs. 19.8 months, respectively), the disease model was less accurate in estimating differences between treatments (median OS simulated vs. observed population: 18.6 vs. 17.9 [abiraterone acetate plus prednisone], 24.0 vs. 25.0 [enzalutamide], 20.2 vs. 18.7 [docetaxel], and 20.0 vs. 23.8 months [radium-223]).

CONCLUSIONS

Overall, the disease model accurately approximated the observed data in the total CRPC population. However, the disease model was unable to predict differences in survival between treatments due to unobserved differences. Therefore, the model is not suitable for cost-effectiveness analysis of CRPC treatment. Using a combination of RWD and data from randomised controlled trials to estimate treatment effectiveness may improve the model.

Symptomatic Skeletal Events and the Use of Bone Health Agents in a Real-World Treated Metastatic Castration Resistant Prostate Cancer Population: Results From the CAPRI-Study in the Netherlands

BACKGROUND

Patients with metastatic castration resistant prostate cancer (mCRPC) are at risk of symptomatic skeletal events (SSE). Bone health agents (BHA, ie bisphosphonates and denosumab) and new life-prolonging drugs (LPDs) can delay SSEs. The aim of this study is to investigate the use of BHAs in relation to SSEs in treated real-world mCRPC population.

PATIENTS AND METHODS

We included patients from the CAPRI registry who were treated with at least one LPD and diagnosed with bone metastases prior to the start of first LPD (LPD1). Outcomes were SSEs (external beam radiation therapy (EBRT) to the bone, orthopedic surgery, pathologic fracture or spinal cord compression) and SSE-free survival (SSE-FS) since LPD1.

RESULTS

One-thousand nine hundred and twenty-three patients were included with a median follow-up from LPD1 of 16.7 months. Fifty-two percent (n = 996) started BHA prior or within 4 weeks after the start of LPD1 (early BHA). In total, 41% experienced at least one SSE. SSE incidence rate was 0.29 per patient year for patients without BHA and 0.27 for patients with early BHA. Median SSE-FS from LPD1 was 12.9 months. SSE-FS was longer in patients who started BHA early versus patients without BHA (13.2 vs. 11.0 months, P = .001).

CONCLUSION

In a real-world population we observed an undertreatment with BHAs, although patients with early BHA use had lower incidence rates of SSEs and longer SSE-FS. This finding was irrespective of type of SSE and presence of risk factors. In addition to LPD treatment, timely initiation of BHAs is recommended in bone metastatic CRPC-patients with both pain and/or opioid use and prior SSE.

Real-world data from expanded access programmes in health technology assessments: a review of NICE technology appraisals

OBJECTIVES

To quantify and characterise the usage of expanded access (EA) data in National Institute for Health and Care Excellence (NICE) technology appraisals (TAs). EA offers patients who are ineligible for clinical trials or registered treatment options, access to investigational therapies. Although EA programmes are increasingly used to collect real-world data, it is unknown if and how these date are used in NICE health technology assessments.

DESIGN

Cross-sectional study of NICE appraisals (2010-2020). We automatically downloaded and screened all available appraisal documentation on NICE website (over 8500 documents), searching for EA-related terms. Two reviewers independently labelled the EA usage by disease area, and whether it was used to inform safety, efficacy and/or resource use. We qualitatively describe the five appraisals with the most occurrences of EA-related terms.

PRIMARY OUTCOME MEASURE

Number of TAs that used EA data to inform safety, efficacy and/or resource use analyses.

RESULTS

In 54.2% (206/380 appraisals), at least one reference to EA was made. 21.1% (80/380) of the TAs used EA data to inform safety (n=43), efficacy (n=47) and/or resource use (n=52). The number of TAs that use EA data remained stable over time, and the extent of EA data utilisation varied by disease area (p=0.001).

CONCLUSION

NICE uses EA data in over one in five appraisals. In synthesis with evidence from well-controlled trials, data collected from EA programmes may meaningfully inform cost-effectiveness modelling.

Nonmetastatic Castration-Resistant Prostate Cancer: Current Challenges and Trends

Prostate carcinoma is a highly prevalent biologically and clinically diverse disease, generally associated with a consistent elevation of prostate-specific antigen levels. Castration-resistant prostate cancer represents a heterogeneous clinical setting that ranges from patients with an asymptomatic prostate-specific antigen elevation after hormone blockade failure and good performance status to patients with significant debilitating symptoms and rapidly progressive disease, leading to death. Nonmetastatic castration-resistant prostate cancer is a transient disease stage defined over specific criteria established within a sensitive time period. The majority of the patients with nonmetastatic castration-resistant prostate cancer will eventually develop metastatic lesions, associated with prostate cancer-specific morbidity and mortality. However, progression to metastatic disease is a heterogeneous process still not fully understood, with studies suggesting that younger age, high Gleason score (> 7), high prostate-specific antigen levels, reduced prostate-specific antigen doubling time (< 6 months), and a rapid alkaline phosphatase rise as potentially associated factors. Although the nonmetastatic castration-resistant prostate cancer treatment landscape has substantially evolved in recent years, the disease heterogeneity makes treatment decisions for this population challenging in the effort to achieve a balance between the risk of disease progression and the toxicity of new treatments in patients who often have associated comorbidities, yet are generally asymptomatic. The present article addresses the current main challenges in nonmetastatic castration-resistant prostate cancer management, including in diagnosis, owing to the development of new imaging modalities with a direct impact in disease detection, prognostic classification, as a result of the traditionally oversimplified definition of disease aggressiveness (mainly based on prostate-specific antigen doubling time), and patient selection for the most adequate treatment.

Mortality in men with castration‐resistant prostate cancer—A long‐term follow‐up of a population‐based real‐world cohort

Objectives

The objective of this study is to find clinical variables that predict the prognosis for men with castration‐resistant prostate cancer (CRPC) in a Swedish real‐life CRPC cohort, including a risk group classification to clarify the risk of succumbing to prostate cancer. This is a natural history cohort representing the premodern drug era before the introduction of novel hormonal drug therapies.

Methods

PSA tests from the clinical chemistry laboratories serving health care in six regions of Sweden were retrieved and cross‐linked to the National Prostate Cancer Registry (NPCR) to identify men with a prostate cancer diagnosis. Through further cross‐linking with data sources at the Swedish Board of Health and Welfare, we retrieved other relevant information such as prescribed drugs, hospitalizations, and cause of death. Men entered the CRPC cohort at the first date of doubling of their PSA nadir value with the last value being >2 ng/ml, or an absolute increase of >5 ng/ml or more, whilst on 3 months of medical castration or if they had been surgically castrated (n = 4098). By combining the two variables with the largest C‐statistics, “PSA at time of CRPC” and “PSA doubling time,” a risk group classification was created.

Results

PSA‐DT and PSA at date of CRPC are the strongest variables associated with PC specific survival. At the end of follow‐up, the proportion of men who died due to PC was 57%, 71%, 81%, 86%, and 89% for risk categories one through five, respectively. The median overall survival in our cohort of men with CRPC was 1.86 years (95% CI: 1.79–1.97).

Conclusion

For a man with castration‐resistant prostate cancer, there is a high probability that this will be the main cause contributing to his death. However, there is a significant difference in mortality that varies in relation to tumor burden assessed as PSA doubling time and PSA at time of CRCP. This information could be used in a clinical setting when deciding when to treat more or less aggressively once entering the CRPC phase of the disease.

The effects of new life-prolonging drugs for metastatic castration-resistant prostate cancer (mCRPC) patients in a real-world population

BACKGROUND

In 2004 docetaxel was the first life-prolonging drug (LPD) registered for metastatic castration-resistant prostate cancer (mCRPC) patients. Between 2011 and 2014 new LPDs for mCRPC (cabazitaxel, abiraterone, enzalutamide, and radium-223) were introduced in the Netherlands. The objective of this study is to assess the impact of the introduction of new LPDs on treatment patterns and overall survival (OS) over time.

PATIENTS AND METHODS

CRPC patients diagnosed in the years 2010-2016 in the observational, retrospective CAPRI registry (20 hospitals) were included and followed up to 2018. Two subgroups were analyzed: treatment-naïve patients (subgroup 1, n = 3600) and post-docetaxel patients (subgroup 2, n = 1355).

RESULTS

In both subgroups, the use of any LPD increased: from 57% (2010-2011) to 69% (2014-2015) in subgroup 1 and from 65% (2011-2012) to 79% (2015-2016) in subgroup 2. Chemotherapy as first mCRPC-treatment (i.e., docetaxel) and first post-docetaxel treatment (i.e., cabazitaxel or docetaxel rechallenge) decreased (46-29% and 20-9% in subgroup 1 and 2, respectively), while the use of androgen-receptor targeting treatments (ART) increased from 11% to 39% and 46% to 64% in subgroup 1 and 2, respectively. In subgroup 1, median OS (mOS) from diagnosis CRPC increased from 28.5 months to 31.0 months (p = 0.196). In subgroup 2, mOS from progression on docetaxel increased from 7.9 months to 12.5 months (p < 0.001). After multiple imputations of missing values, in multivariable cox-regression analysis with known prognostic parameters, the treatment period was independent significant for OS in subgroup 1 (2014-2015 vs. 2010-2011 with HR 0.749, p < 0.001) and subgroup 2 (2015-2016 vs. 2011-2012 with HR 0.811, p = 0.037).

CONCLUSION

Since 2010, a larger proportion of mCRPC patients was treated with LPDs, which was related to an increased mOS.

High-Intensity Care in the End-of-Life Phase of Castration-Resistant Prostate Cancer Patients: Results from the Dutch CAPRI-Registry

Background: Intensive end-of-life care (i.e., the overuse of treatments and hospital resources in the last months of life), is undesirable since it has a minimal clinical benefit with a substantial financial burden. The aim was to investigate the care in the last three months of life (end-of-life [EOL]) in castration-resistant prostate cancer (CRPC). Methods: Castration-resistant prostate cancer registry (CAPRI) is an investigator-initiated, observational multicenter cohort study in 20 hospitals retrospectively including patients diagnosed with CRPC between 2010 and 2016. High-intensity care was defined as the initiation of life-prolonging drugs (LPDs) in the last month, continuation of LPD in last 14 days, >1 admission, admission duration ≥14 days, and/or intensive care admission in last three months of life. Descriptive and binary logistic regression analyses were performed. Results: High-intensity care was experienced by 41% of 2429 patients in the EOL period. Multivariable analysis showed that age (odds ratio [OR] 0.98, 95% confidence interval [CI] 0.97-0.99), performance status (OR 0.57, 95% CI 0.33-0.97), time from CRPC to EOL (OR 0.98, 95% CI 0.97-0.98), referral to a medical oncologist (OR 1.99, 95% CI 1.55-2.55), prior LPD treatment (>1 line OR 1.72, 95% CI 1.31-2.28), and opioid use (OR 1.45, 95% CI 1.08-1.95) were significantly associated with high-intensity care. Conclusions: High-intensity care in EOL is not easily justifiable due to high economic cost and little effect on life span, but further research is awaited to give insight in the effect on patients' and their caregivers' quality of life.

Safety and survival of docetaxel and cabazitaxel in metastatic castration-resistant prostate cancer

OBJECTIVES

To investigate real-world haematological toxicity, overall survival (OS) and the treatment characteristics of docetaxel and cabazitaxel chemotherapy in metastatic castration-resistant prostate cancer (mCRPC).

PATIENTS AND METHODS

This retrospective claims data study followed patients with mCRPC receiving cabazitaxel or docetaxel from their first chemotherapy infusion. Haematological toxicities were measured using treatment codes and inpatient diagnoses. OS was estimated using the Kaplan-Meier method. A multivariable Cox regression analysis was used to identify OS predictors.

RESULTS

Data from 539 patients administered docetaxel and 240 administered cabazitaxel were analysed. Regarding adverse events, within 8 months of treatment initiation, some kind of treatment for haematological toxicity was documented in 31% of patients given docetaxel and in 61% of patients given cabazitaxel. In the same period, hospitalization associated with haematological toxicity was documented in 11% of the patients in the docetaxel cohort and in 15% of the patients in the cabazitaxel cohort. In the docetaxel cohort, 9.9% of patients required reverse isolation and 13% were diagnosed with sepsis during hospitalization. In the cabazitaxel cohort, the cumulative incidence was 7.9% and 15%, respectively. The median OS was reached at 21.9 months in the docetaxel cohort and, because of a later line of therapy, at 11.3 months in the cabazitaxel cohort. A multivariate Cox regression revealed that indicators of locally advanced and metastatic disease, severe comorbidities, and prior hormonal/cytotoxic therapies were independent predictors of early death.

CONCLUSION

Cabazitaxel patients face an increased risk of haematological toxicities during treatment. Together with their short survival time, this calls for a strict indication when using cabazitaxel in patients with mCRPC.

Nomograms to predict outcomes after 177Lu-PSMA therapy in men with metastatic castration-resistant prostate cancer: an international, multicentre, retrospective study

BACKGROUND

Lutetium-177 (¹⁷⁷Lu) prostate-specific membrane antigen (¹⁷⁷Lu-PSMA) is a novel targeted treatment for patients with metastatic castration-resistant prostate cancer (mCRPC). Predictors of outcomes after ¹⁷⁷Lu-PSMA to enhance its clinical implementation are yet to be identified. We aimed to develop nomograms to predict outcomes after ¹⁷⁷Lu-PSMA in patients with mCRPC.

METHODS

In this multicentre, retrospective study, we screened patients with mCRPC who had received ¹⁷⁷Lu-PSMA between Dec 10, 2014, and July 19, 2019, as part of the previous phase 2 trials (NCT03042312, ACTRN12615000912583) or compassionate access programmes at six hospitals and academic centres in Germany, the USA, and Australia. Eligible patients had received intravenous 6·0-8·5 GBq ¹⁷⁷Lu-PSMA once every 6-8 weeks, for a maximum of four to six cycles, and had available baseline [⁶⁸Ga]Ga-PSMA-11 PET/CT scan, clinical data, and survival outcomes. Putative predictors included 18 pretherapeutic clinicopathological and [⁶⁸Ga]Ga-PSMA-11 PET/CT variables. Data were collected locally and centralised. Primary outcomes for the nomograms were overall survival and prostate-specific antigen (PSA)-progression-free survival. Nomograms for each outcome were computed from Cox regression models with LASSO penalty for variable selection. Model performance was measured by examining discrimination (Harrell's C-index), calibration (calibration plots), and utility (patient stratification into low-risk vs high-risk groups). Models were validated internally using bootstrapping and externally by calculating their performance on a validation cohort.

FINDINGS

Between April 23, 2019, and Jan 13, 2020, 414 patients were screened; 270 (65%) of whom were eligible and were divided into development (n=196) and validation (n=74) cohorts. The median duration of follow-up was 21·5 months (IQR 13·3-30·7). Predictors included in the nomograms were time since initial diagnosis of prostate cancer, chemotherapy status, baseline haemoglobin concentration, and [⁶⁸Ga]Ga-PSMA-11 PET/CT parameters (molecular imaging TNM classification and tumour burden). The C-index of the overall survival model was 0·71 (95% CI 0·69-0·73). Similar C-indices were achieved at internal validation (0·71 [0·69-0·73]) and external validation (0·72 [0·68-0·76]). The C-index of the PSA-progression-free survival model was 0·70 (95% CI 0·68-0·72). Similar C-indices were achieved at internal validation (0·70 [0·68-0·72]) and external validation (0·71 [0·68-0·74]). Both models were adequately calibrated and their predictions correlated with the observed outcome. Compared with high-risk patients, low-risk patients had significantly longer overall survival in the validation cohort (24·9 months [95% CI 16·8-27·3] vs 7·4 months [4·0-10·8]; p<0·0001) and PSA-progression-free survival (6·6 months [6·0-7·1] vs 2·5 months [1·2-3·8]; p=0·022).

INTERPRETATION

These externally validated nomograms that are predictive of outcomes after ¹⁷⁷Lu-PSMA in patients with mCRPC might help in clinical trial design and individual clinical decision making, particularly at institutions where ¹⁷⁷Lu-PSMA is introduced as a novel therapeutic option.

FUNDING

Prostate Cancer Foundation.

Real world treatment utilization patterns in patients with castration-resistant prostate cancer

BACKGROUND

Studies describing treatment utilization for castration-resistant prostate cancer (CRPC) are limited. We aimed to describe the treatment utilization of a contemporary population-based CRPC cohort between 2006 and 2016.

METHODS

We identified 1699 men with a PC diagnosis between 2005 and 2015, who developed CRPC between 2006 and 2015 in the Stockholm region of Sweden. Demographic information, stage and grade at PC diagnosis, stage at CRPC, prostate-specific antigen (PSA) nadir, PSA doubling time, treatment utilization rate within 1 year of CRPC diagnosis, reason for stopping therapy, treatment sequence trajectory, overall and PC specific survival was described.

RESULTS

Treatment for men with de novo metastatic disease (n = 463) was 32%, treatment for men with progressive metastatic disease after PC diagnosis (n = 66) was 44%, treatment for men with nonmetastatic CRPC (n = 113) was 34% and treatment for those with an unknown stage at time of CRPC diagnosis (n = 857) was 12%. Docetaxel was used in 39%, abiraterone acetate plus prednisone in 15%, enzalutamide in 13%, cabazitaxel in 11% and radium-223 in 5% of treatments. Treatment increased from 22% in 2006-2009 for metastatic cancer to 50% in 2013-2015 (p < .001). Factors associated with treatment were an unknown stage at diagnosis (OR: 0.3, 95% CI: 0.2-0.4), age ≥75 years (OR: 0.2, 95% CI: 0.1 - 0.3), PSA doubling time >3 months (OR: 0.4, 95% CI: 0.3 - 0.6) and a diagnosis between 2013 and 2015 (OR: 3.4, 95% CI: 2.0 - 5.8).

CONCLUSIONS

Despite treatment availability, in this large real-world cohort we found treatment utilization to remain low.

Impact of DNA damage repair defects and aggressive variant features on response to carboplatin-based chemotherapy in metastatic castration-resistant prostate cancer

Platinum‐based chemotherapy is not standard of care for unselected or genetically selected metastatic castration‐resistant prostate cancer (mCRPC) patients. A retrospective assessment of 71 patients was performed on platinum use in the Netherlands. Genetically unselected patients yielded low response rates. For a predefined subanalysis of all patients with comprehensive next‐generation sequencing, 30 patients were grouped based on the presence of pathogenic aberrations in genes associated with DNA damage repair (DDR) or aggressive variant prostate cancer (AVPC). Fourteen patients (47%) were DDR deficient (DDRd), of which seven with inactivated BRCA2 (BRCA2mut). Six patients classified as AVPC. DDRd patients showed beneficial biochemical response to carboplatin, largely driven by all BRCA2mut patients having >50% prostate‐specific antigen (PSA) decline and objective radiographic response. In the wild‐type BRCA2 subgroup, 35% had a >50% PSA decline (P = .006) and 16% radiographic response (P < .001). Median overall survival was 21 months for BRCA2mut patients vs 7 months (P = .041) for those with functional BRCA2. AVPC patients demonstrated comparable responses to non‐AVPC, including a similar overall survival, despite the poor prognosis for this subgroup. In the scope of the registration of poly‐(ADP)‐ribose polymerase inhibitors (PARPi) for mCRPC, we provide initial insights on cross‐resistance between PARPi and platinum compounds. By combining the literature and our study, we identified 18 patients who received both agents. In this cohort, only BRCA2mut patients treated with platinum first (n = 4), responded to both agents. We confirm that BRCA2 inactivation is associated with meaningful responses to carboplatin, suggesting a role for both PARPi and platinum‐based chemotherapy in preselected mCRPC patients.

What's new?

Platinum‐based chemotherapy is not standard of care for unselected or genetically‐selected patients with metastatic castration‐resistant prostate cancer (mCRPC). However, several studies have shown that platinum‐based chemotherapy may still have a role in postponing progression in selected patient groups. This new study investigating DNA damage repair gene alterations and response to platinum‐based chemotherapy provides evidence that deep and durable responses are primarily associated with patients harbouring BRCA2 inactivation. Based on these data and the limited available literature, platinum‐based chemotherapy followed by PARP inhibition is potentially emerging as the optimal treatment sequence in pre‐selected mCRPC patients.

Awareness, Knowledge, and Utility of RCT Data vs RWE: Results From a Survey of US Cardiologists: Real-world Evidence in Clinical Decision Making

Real-world evidence (RWE) provides a potential rich source of additional information to the body of data available from randomized clinical trials (RCTs), but there is a need to understand the strengths and limitations of RWE before it can be applied to clinical practice. To gain insight into current thinking in clinical decision making and utility of different data sources, a representative sampling of US cardiologists selected from the current, active Fellows of the American College of Cardiology (ACC) were surveyed to evaluate their perceptions of findings from RCTs and RWE studies and their application in clinical practice. The survey was conducted online via the ACC web portal between 12 July and 11 August 2017. Of the 548 active ACC Fellows invited as panel members, 173 completed the survey (32% response), most of whom were board certified in general cardiology (n = 119, 69%) or interventional cardiology (n = 40, 23%). The survey results indicated a wide range of familiarity with and utilization of RWE amongst cardiologists. Most cardiologists were familiar with RWE and considered RWE in clinical practice at least some of the time. However, a significant minority of survey respondents had rarely or never applied RWE learnings in their clinical practice, and many did not feel confident in the results of RWE other than registry data. These survey findings suggest that additional education on how to assess and interpret RWE could help physicians to integrate data and learnings from RCTs and RWE to best guide clinical decision making.

A clinician's guide for developing a prediction model: a case study using real-world data of patients with castration-resistant prostate cancer

PURPOSE

With the increasing interest in treatment decision-making based on risk prediction models, it is essential for clinicians to understand the steps in developing and interpreting such models.

METHODS

A retrospective registry of 20 Dutch hospitals with data on patients treated for castration-resistant prostate cancer was used to guide clinicians through the steps of developing a prediction model. The model of choice was the Cox proportional hazard model.

RESULTS

Using the exemplary dataset several essential steps in prediction modelling are discussed including: coding of predictors, missing values, interaction, model specification and performance. An advanced method for appropriate selection of main effects, e.g. Least Absolute Shrinkage and Selection Operator (LASSO) regression, is described. Furthermore, the assumptions of Cox proportional hazard model are discussed, and how to handle violations of the proportional hazard assumption using time-varying coefficients.

CONCLUSION

This study provides a comprehensive detailed guide to bridge the gap between the statistician and clinician, based on a large dataset of real-world patients treated for castration-resistant prostate cancer.

Real-world outcomes of radium-223 dichloride for metastatic castration resistant prostate cancer

Aim: Timing of radium-223 (Ra-223) in metastatic castration-resistant prostate cancer (mCRPC) remains challenging due to alternative options and short window of opportunity. Methods: Ra-223 treated patients in the CAPRI-registry were included. Outcomes were evaluated based on treatment line of Ra-223. Results: Out of 285 patients, 49% received Ra-223 in line ≥3. 51% completed six Ra-223 injections and 34% had a symptomatic skeletal event after first Ra-223 without differences between subgroups. After correction of known prognostic factors Ra-223 in line ≥3 (HR: 3.267; 95% CI: 1.689-6.317; p < 0.01) remained associated with worse OS. Conclusion: In the Netherlands, Ra-223 was mainly started as second or third mCRPC-treatment in 2014-2018. Later timing of Ra-223 did affect OS, but not treatment completion and occurrence of symptomatic skeletal events.

Use of record linkage to evaluate treatment outcomes and trial eligibility in a real-world metastatic prostate cancer population in Scotland

Purpose

New treatments are introduced into standard care based on clinical trial results. However, it is not clear if these benefits are reflected in the broader population. This study analysed the clinical outcomes of patients with metastatic castration‐resistant prostate cancer, treated with abiraterone and enzalutamide, within the Scottish National Health Service.

Methods

Retrospective cohort study using record linkage of routinely collected healthcare data (study period: February 2012 to February 2017). Overall survival (OS) was analysed using Kaplan‐Meier methods and Cox Proportional Hazard models; a subgroup analysis comprised potentially trial‐eligible patients.

Results

Overall, 271 patients were included and 73.8% died during the study period. Median OS was poorer than in the pivotal trials, regardless of medication and indication: 10.8 months (95% confidence interval [CI] 8.6‐15.1) and 20.9 months (95% CI 14.9‐29.0) for abiraterone, and 12.6 months (95% CI 10.5‐18.2) and 16.0 months (95% CI 9.8—not reached) for enzalutamide, post and pre chemotherapy, respectively. Only 46% of patients were potentially “trial eligible” and in this subgroup OS improved. Factors influencing survival included baseline performance status, and baseline prostate‐specific antigen, alkaline phosphatase, and albumin levels.

Conclusions

Poorer prognostic features of non‐trial eligible patients impact real‐world outcomes of cancer medicines. Electronic record linkage of routinely collected healthcare data offers an opportunity to report outcomes on cancer medicines at scale and describe population demographics. The availability of such observational data to supplement clinical trial results enables patients and clinicians to make more informed treatment decisions, and policymakers to contextualise trial findings.

Real-World Evidence of Clinical Outcomes in Precision Radionuclide Oncology: The NIGHTCAP Study of 177Lu-PSMA in Metastatic Prostate Cancer

A novel approach to current radiopharmaceutical study design to document the efficiency of 177Lu- PSMA-radioligand therapy of metastatic prostate cancer is described in a proposed prospective, real-time, realworld audit of a large patient population worldwide. The NIGHTCAP (National Investigators Global Harmonisation Theragnostics of Cancer of Prostate) Study will establish real-world evidence (RWE) of overall survival (OS) and quality of life (QoL) in patients undergoing routine 177Lu-PSMA-radioligand therapy on harmonised compassionate patient-usage protocols throughout the world. Such long-term efficiency data will be contrasted with the short-term randomised controlled trial (RCT) assessments of efficacy predicated upon surrogate markers of survival outcomes, such as progression-free survival (PFS). The shortcomings of RCT evaluation of the clinical benefit of new anticancer agents are detailed in this review, which advocates RWE to determine efficiency. The real-time monitoring of QoL in the NIGHTCAP Study is independent of questionnaires, language differences, or oncologist bias, and relies upon individual patient self-assessment by choice of one of five emoji which best reflects their mood each day.

The impact of patient characteristics on enzalutamide pharmacokinetics and how this relates to treatment toxicity and efficacy in metastatic prostate cancer patients

Purpose

The aim of the study is to investigate the influence of patient characteristics, age and body mass index (BMI), on pharmacokinetics of enzalutamide, and to study the relationships between drug exposure and enzalutamide efficacy and toxicity, in mCRPC patients.

Methods

Data were collected in a longitudinal cohort study (ANDROPS) and a prospective observational study (ILUMINATE), both in mCRPC patients treated with enzalutamide. To investigate the influence of age and BMI on exposure, enzalutamide and N-desmethylenzalutamide levels were compared by ANOVA. To investigate the relation of exposure versus time to progression (TTP), the sum plasma levels were divided into quartiles and compared by Kaplan–Meier analysis. To assess the relation of exposure with fatigue, plasma levels in patients experiencing fatigue vs. no fatigue were compared by and independent t test.

Results

Data of 68 mCRPC patients were included for analysis. Plasma levels were not different for age or BMI. No difference in TTP between both studies was observed (383 days (95% CI 287–859), and 567 days (95% CI 351–NR), p = 0.36). Kaplan–Meier analysis of quartiles of sum levels showed no difference for TTP. Fatigue was reported by 22 patients, no difference in sum plasma levels was observed between patients with and without fatigue.

Conclusions

We observed that age and BMI did not influence systemic exposure in patients treated with enzalutamide. No relation of exposure with efficacy or fatigue was observed. Further research using enzalutamide at a lower dose is needed to understand the relation of enzalutamide exposure and fatigue.

Health-related Quality of Life and Pain in a Real-world Castration-resistant Prostate Cancer Population: Results From the PRO-CAPRI Study in the Netherlands

BACKGROUND

The purpose of this study was to determine generic, cancer-specific, and prostate cancer-specific health-related quality of life (HRQoL), pain and changes over time in patients with metastatic castration-resistant prostate cancer (mCRPC) in daily practice.

PATIENTS AND METHODS

PRO-CAPRI is an observational, prospective study in 10 hospitals in the Netherlands. Patients with mCRPC completed the EQ-5D, European Organization for the Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ-C30), and Brief Pain Inventory-Short Form (BPI-SF) every 3 months and European Organization for the Research and Treatment of Cancer Quality of Life Questionnaire-Prostate Cancer Module (EORTC QLQ-PR25) every 6 months for a maximum of 2 years. Subgroups were identified based on chemotherapy pretreatment. Outcomes were generic, cancer-specific, and prostate cancer-specific HRQoL and self-reported pain. Descriptive statistics were performed including changes over time and minimal important differences (MID) between subgroups.

RESULTS

In total, 151 included patients answered 873 questionnaires. The median follow-up from the start of the study was 19.5 months, and 84% were treated with at least 1 life-prolonging agent. Overall, patients were in good clinical condition (Eatern Cooperative Oncology Group performance status 0-1 in 78%) with normal baseline hemoglobin, lactate dehydrogenase, and alkaline phosphatase. At inclusion, generic HRQoL was high with a mean EQ visual analog score of 73.2 out of 100. The lowest scores were reported on role and physical functioning (mean scores of 69 and 76 of 100, respectively), and fatigue, pain, and insomnia were the most impaired domains. These domains deteriorated in > 50% of patients.

CONCLUSION

Although most patients were treated with new treatments during follow-up, mCRPC has a negative impact on HRQoL with deterioration in all domains over time, especially role and physical functioning. These domains need specific attention during follow-up to maintain HRQoL as long as possible by timely start of adequate supportive care management.

Real-world Outcomes of Sequential Androgen-receptor Targeting Therapies with or Without Interposed Life-prolonging Drugs in Metastatic Castration-resistant Prostate Cancer: Results from the Dutch Castration-resistant Prostate Cancer Registry

BACKGROUND

Cross resistance between androgen-receptor targeting therapies (ARTs) (abiraterone acetate plus prednisone [ABI+P] or enzalutamide [ENZ]) for treatment of metastatic castration-resistant prostate cancer (mCRPC) may affect responses to second ART (ART2).

OBJECTIVE

To establish treatment duration and prostate-specific antigen (PSA) response of ART2 in real-world mCRPC patients treated with or without other life-prolonging drugs (LPDs; ie, docetaxel, cabazitaxel, or radium-223) between ART1 and ART2.

DESIGN, SETTING, AND PARTICIPANTS

Castration-resistant prostate cancer patients, diagnosed between 2010 and 2016 were retrospectively registered in Castration-resistant Prostate Cancer Registry (CAPRI). Patients treated with both ARTs were clustered into two subgroups: ART1>ART2 or ART1>LPD>ART2.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Outcomes were ≥50% PSA response and treatment duration of ART2. Descriptive statistics and binary logistic regression after multiple imputations were performed.

RESULTS AND LIMITATIONS

A total of 273 patients were included with a median follow-up of 8.4 mo from ART2. Patients with ART1>ART2 were older and had favourable prognostic characteristics at ART2 baseline compared with patients with ART1>LPD>ART2. No differences between ART1>ART2 and ART1>LPD>ART2 were found in PSA response and treatment duration. Multivariate analysis suggested that PSA response of ART2 was less likely in patients with visceral metastases (odds ratio [OR] 0.143, p=0.04) and more likely in patients with a relatively longer duration of androgen-deprivation treatment (OR 1.028, p=0.01) and with ABI + P before ENZ (OR 3.192, p=0.02). A major limitation of this study was missing data, a common problem in retrospective observational research.

CONCLUSIONS

The effect of ART2 seems to be low, with a low PSA response rate and a short treatment duration irrespective of interposed chemotherapy or radium-223, especially in patients with short time on castration, visceral disease, and ENZ before ABI+P.

PATIENT SUMMARY

We observed no differences in outcomes of patients treated with sequential abiraterone acetate plus prednisone (ABI+P) and enzalutamide (ENZ) with or without interposed chemotherapy or radium-223. In general, outcomes were lower than those in randomised trials, questioning the additional effect of second treatment with ABI+P or ENZ in daily practice.

Efficacy and safety of abiraterone acetate plus prednisone vs. cabazitaxel as a subsequent treatment after first-line docetaxel in metastatic castration-resistant prostate cancer: results from a prospective observational study (CAPRO)

BACKGROUND

To describe the patterns of second-line treatment of patients with metastatic castration-resistant prostate cancer (mCRPC) after docetaxel treatment in a Spanish population, to identify the factors associated with those patterns, and to compare the efficacy and safety of the treatments most frequently administered.

METHODS

Observational, prospective study conducted in patients with histologically or cytologically confirmed prostate adenocarcinoma; documented metastatic castration-resistant disease; progression after first-line, docetaxel-based chemotherapy with or without other agents.

RESULTS

Of the 150 patients recruited into the study, 100 patients were prescribed abiraterone acetate plus prednisone (AAP), 44 patients received cabazitaxel plus prednisone (CP), and 6 patients received other treatments. Age (odds ratio [OR] 1.06, 95% [confidence interval] CI 1.01 to 1.11) and not elevated lactate dehydrogenase (LDH) levels (OR 0.33, 95% CI 0.14 to 0.76) were independently associated with the administration of AAP. Treatment with AAP was associated with significantly longer clinical/radiographic progression-free survival (hazard ratio [HR] 0.57, 95% CI 0.38 to 0.85) and overall survival (OS; HR 0.40, 95% CI 0.21 to 0.76) compared to CP, while no significant differences between the treatments were found regarding biochemical progression-free survival (PFS; HR 0.78 [95% CI 0.49 to 1.24]). However, in a post-hoc Cox regression analysis adjusted for potential confounders there were not differences between AAP and CP in any of the time-to-event outcomes, including overall survival. We observed no new safety signals related to either regimen.

CONCLUSION

Second-line AAP for patients with mCRPC is the most common treatment strategy after progression with a docetaxel-based regimen. When controlling for potential confounders, patients receiving this treatment showed no differences in PFS and OS in comparison to those receiving CP, although these latter results should be confirmed in randomized controlled trials.

Second-Line Cabazitaxel Treatment in Castration-Resistant Prostate Cancer Clinical Trials Compared to Standard of Care in CAPRI: Observational Study in the Netherlands

BACKGROUND

Cabazitaxel has been shown to improve overall survival (OS) in metastatic castration-resistant prostate cancer (mCRPC) patients after docetaxel in the TROPIC trial. However, trial populations may not reflect the real-world population. We compared patient characteristics and outcomes of cabazitaxel within and outside trials (standard of care, SOC).

PATIENTS AND METHODS

mCRPC patients treated with cabazitaxel directly after docetaxel therapy before 2017 were retrospectively identified and followed to 2018. Patients were grouped on the basis of treatment within a trial or SOC. Outcomes included OS and prostate-specific antigen (PSA) response.

RESULTS

From 3616 patients in the CAPRI registry, we identified 356 patients treated with cabazitaxel, with 173 patients treated in the second line. Trial patients had favorable prognostic factors: fewer symptoms, less visceral disease, lower lactate dehydrogenase, higher hemoglobin, more docetaxel cycles, and longer treatment-free interval since docetaxel therapy. PSA response (≥ 50% decline) was 28 versus 12%, respectively (P = .209). Median OS was 13.6 versus 9.6 months for trial and SOC subgroups, respectively (hazard ratio = 0.73, P = .067). After correction for prognostic factors, there was no difference in survival (hazard ratio = 1.00, P = .999). Longer duration of androgen deprivation therapy treatment, lower lactate dehydrogenase, and lower PSA were associated with longer OS; visceral disease had a trend for shorter OS.

CONCLUSION

Patients treated with cabazitaxel in trials were fitter and showed outcomes comparable to registration trials. Conversely, those treated in daily practice showed features of more aggressive disease and worse outcome. This underlines the importance of adequate estimation of trial eligibility and health status of mCRPC patients in daily practice to ensure optimal outcomes.

Comparison of outcomes of radiotherapy-treated localized prostate cancer patients within a clinical trial setting versus real-life setting

AIM

To assess whether clinical trial participation affects survival outcomes of radiotherapy-treated localized prostate cancer patients compared with similar treatment within a real-world setting.

METHODS

This is a comparative analysis of the outcomes of localized prostate cancer patients treated within two clinical trials (NCT00331773; NCT00004054) versus the outcomes of similar cohorts of patients registered within the SEER database and treated with radiotherapy. Propensity score matching was conducted to account for heterogeneity in background patient information. Within the postmatching cohort, Kaplan-Meier survival according to treatment setting was reconducted. Moreover, an assessment of the impact of treatment setting on overall survival (OS) was conducted in a multivariate Cox regression model adjusted for age, race, ethnicity, T-stage, PSA and Gleason score.

RESULTS

A total of 5209 low-risk patients and 2115 high-risk patients were included in the current analysis. For both low- and high-risk disease, Kaplan-Meier analysis for OS in the postmatching cohort did not show any difference in OS between patients treated within clinical trial setting versus patients treated within SEER database (p = 0.176; p = 0.097; respectively). Likewise in multivariate Cox regression analysis, treatment context (clinical trial vs SEER) does not affect OS for either low- or high-risk disease (p = 0.470; p = 0.412; respectively).

CONCLUSION

After accounting for possible confounders in baseline characteristics, there was no conclusive evidence of a survival difference between localized prostate cancer patients treated with external beam radiotherapy within routine, real-world settings compared with patients treated within clinical trials.

Validation of multiple myeloma risk stratification indices in routine clinical practice: Analysis of data from the Czech Myeloma Group Registry of Monoclonal Gammopathies

This study used data from the Czech Myeloma Group Registry of Monoclonal Gammopathies to validate the International Myeloma Working Group (IMWG) and revised International Staging System (R-ISS) indices for risk stratification in patients with multiple myeloma (MM) in clinical practice. Patients were included if they had symptomatic MM, complete data allowing R-ISS and IMWG staging (including cytogenetic information regarding t(4;14), t(14;16), and del(17p)), and key parameters for treatment evaluation. Median overall survival (OS) in included patients (n = 550) was 47.7 (95% CI: 39.5-55.9) and 46.2 (95% CI: 38.9-53.5) months from diagnosis and initiation of first-line therapy, respectively. Patients categorized as higher vs lower risk had reduced survival; median OS from diagnosis was 35.4 (95% CI: 30.5-40.3) vs 58.3 (95% CI: 53.8-62.9) months in high-risk vs other patients (IMWG; P = .001) and 34.1 (95% CI: 30.2-38.0) vs 47.2 (95% CI: 43.4-51.0) months in Stage III vs Stage II patients (R-ISS; P < .001). In conclusion, IMWG and R-ISS risk stratification indices are applicable to patients with MM in a real-world setting.