Safety of cabazitaxel in senior adults with metastatic castration-resistant prostate cancer: Results of the European compassionate-use programme

Pain and Health-related Quality of Life with Biweekly Versus Triweekly Cabazitaxel Schedule in Older Men with Metastatic Castration-resistant Prostate Cancer in the Multicenter, Randomized CABASTY Trial

BACKGROUND AND OBJECTIVE

The CABASTY study showed that more frequent administration of a lower dose of cabazitaxel (CBZ) reduced toxicity in older men with metastatic castration-resistant prostate cancer (mCRPC), without compromising efficacy. Here, we investigated the impact of a biweekly CBZ schedule on patient-reported pain and health-related quality of life (HRQoL).

METHODS

We randomized 196 patients from 25 centers (1:1, stratified by age and G8 score) to the biweekly CBZ16 (CBZ 16 mg/m2) experimental arm or the triweekly CBZ25 (CBZ 25 mg/m2) control arm (CABASTY study, NCT02961257). We assessed pain using the Numeric Pain Rating Scale and HRQoL using the Functional Assessment of Cancer Therapy-Prostate (FACT-P) questionnaire.

KEY FINDINGS AND LIMITATIONS

A total of 141 patients were available for a pain and 160 for an HRQoL analysis. Median time to pain progression (stratified hazard ratio [HR]: 1.7, confidence interval [CI]: 0.67-4.22, p = 0.3) and median time to first opiate use (stratified HR: 1.05, CI: 0.44-2.55, p = 0.9) did not differ between arms. We did not see a significant difference in median time to deterioration of FACT-P total score between treatments (stratified HR: 0.88, CI: 0.47-1.7, p = 0.7). Interestingly, the time to onset of several adverse events was significantly longer in the biweekly CBZ16 group.

CONCLUSIONS AND CLINICAL IMPLICATIONS

HRQoL did not significantly differ between the biweekly CBZ16 and the standard schedule. Additionally, onset of some adverse events was delayed. These results may increase health care providers' confidence in using CBZ in older patients with mCRPC who are denied chemotherapy.

PATIENT SUMMARY

Androgen receptor pathway inhibitors are often preferred to taxane chemotherapy as a treatment of second or subsequent line in older metastatic castration-resistant prostate cancer patients due to more frequent treatment-related toxicities. Here, we showed that quality of life and pain did not differ significantly with an adapted schedule of cabazitaxel (CBZ), compared with the standard regimen. This CBZ schedule could increase eligibility of older patients for chemotherapy.

Effectiveness and safety of primary prophylaxis of G-CSF during chemotherapy for prostate cancer, Japanese clinical guideline for appropriate use of G-CSF: clinical practice guidelines for the use of G-CSF 2022

BACKGROUND

Docetaxel (DTX) is commonly used as a primary chemotherapy, and cabazitaxel (CBZ) has shown efficacy in patients who are DTX resistant. Primary prophylactic granulocyte colony stimulating factor (G-CSF) therapy is currently used with CBZ treatment in routine clinical care in Japan.

METHODS

In this study, we performed a systematic review following the Minds guidelines to investigate the effectiveness and safety of primary prophylaxis with G-CSF during chemotherapy for prostate cancer and to construct G-CSF guidelines for primary prophylaxis use during chemotherapy. A comprehensive literature search of various electronic databases (PubMed, Cochrane Library, and Ichushi) was performed on January 10, 2020, to identify studies published between January 1990 and December 31, 2019 that investigate the impact of primary prophylaxis with G-CSF during CBZ administration on clinical outcomes.

RESULTS

Ultimately, nine articles were included in the qualitative systematic review. Primary G-CSF prophylaxis during CBZ administration for metastatic castration-resistant prostate cancer was difficult to assess in terms of correlation with overall survival, mortality from infection, and patients' quality of life. These difficulties were owing to the lack of randomized controlled trials comparing patients with and without primary prophylaxis of G-CSF during CBZ administration. However, some retrospective studies have suggested that it may reduce the incidence of febrile neutropenia.

CONCLUSION

G-CSF may be beneficial as primary prophylaxis during CBZ administration for metastatic castration resistant prostate cancer, and we made a "weak recommendation to perform" with an annotation of the relevant regimen.

Glucocorticoid treatment influences prostate cancer cell growth and the tumor microenvironment via altered glucocorticoid receptor signaling in prostate fibroblasts

Despite significant therapeutic advances in recent years, treatment of metastatic prostate cancer (PCa) remains palliative, owing to the inevitable occurrence of drug resistance. There is increasing evidence that epithelial glucocorticoid receptor (GR) signaling and changes in the tumor-microenvironment (TME) play important roles in this process. Since glucocorticoids (GCs) are used as concomitant medications in the course of PCa treatment, it is essential to investigate the impact of GCs on stromal GR signaling in the TME. Therefore, general GR mRNA and protein expression was assessed in radical prostatectomy specimens and metastatic lesions. Elevated stromal GR signaling after GC treatment resulted in altered GR-target gene, soluble protein expression, and in a morphology change of immortalized and primary isolated cancer-associated fibroblasts (CAFs). Subsequently, these changes affected proliferation, colony formation, and 3D-spheroid growth of multiple epithelial PCa cell models. Altered expression of extra-cellular matrix (ECM) and adhesion-related proteins led to an ECM remodeling. Notably, androgen receptor pathway inhibitor treatments did not affect CAF viability. Our findings demonstrate that GC-mediated elevated GR signaling has a major impact on the CAF secretome and the ECM architecture. GC-treated fibroblasts significantly influence epithelial tumor cell growth and must be considered in future therapeutic strategies.

Biweekly vs Triweekly Cabazitaxel in Older Patients With Metastatic Castration-Resistant Prostate Cancer: The CABASTY Phase 3 Randomized Clinical Trial

Importance

Many patients 65 years or older with metastatic castration-resistant prostate cancer (mCRPC) are denied taxane chemotherapy because this treatment is considered unsuitable.

Objective

To determine whether biweekly cabazitaxel (CBZ), 16 mg/m2 (biweekly CBZ16), plus prophylactic granulocyte colony-stimulating factor (G-CSF) at each cycle reduces the risk of grade 3 or higher neutropenia and/or neutropenic complications (eg, febrile neutropenia, neutropenic infection, or sepsis) compared with triweekly CBZ, 25 mg/m2 (triweekly CBZ25), plus G-CSF (standard regimen).

Design, Setting, and Participants

A total of 196 patients 65 years or older with progressive mCRPC were enrolled in this prospective phase 3 randomized clinical trial conducted in France (18 centers) and Germany (7 centers) between May 5, 2017, and January 7, 2021. All patients had received docetaxel and at least 1 novel androgen receptor-targeted agent.

Interventions

Patients were randomly assigned 1:1 to receive biweekly CBZ16 plus G-CSF and daily prednisolone (experimental group) or triweekly CBZ25 plus G-CSF and daily prednisolone (control group).

Main Outcome and Measures

The primary end point was the occurrence of grade 3 or higher neutropenia measured at nadir and/or neutropenic complications.

Results

Among 196 patients (97 in the triweekly CBZ25 group and 99 in the biweekly CBZ16 group), the median (IQR) age was 74.6 (70.4-79.3) years, and 181 (92.3%) had an Eastern Cooperative Oncology Group performance status of 0 or 1. The median (IQR) follow-up duration was 31.3 (22.5-37.5) months. Relative dose intensities were comparable between groups (median [IQR], 92.7% [83.7%-98.9%] in the triweekly CBZ25 group vs 92.8% [87.0%-98.9%] in the biweekly CBZ16 group). The rate of grade 3 or higher neutropenia and/or neutropenic complications was significantly higher with triweekly CBZ25 vs biweekly CBZ16 (60 of 96 [62.5%] vs 5 of 98 [5.1%]; odds ratio, 0.03; 95% CI, 0.01-0.08; P < .001). Grade 3 or higher adverse events were more common with triweekly CBZ25 (70 of 96 [72.9%]) vs biweekly CBZ16 (55 of 98 [56.1%]). One patient (triweekly CBZ25 group) died of a neutropenic complication.

Conclusions and Relevance

In this randomized clinical trial, compared with the standard regimen, biweekly CBZ16 plus G-CSF significantly reduced by 12-fold the occurrence of grade 3 or higher neutropenia and/or neutropenic complications, with comparable clinical outcomes. The findings suggest that biweekly CBZ16 regimen should be offered to patients 65 years or older with mCRPC for whom the standard regimen is unsuitable.

Trial Registration

ClinicalTrials.gov Identifier: NCT02961257.

Feasibility of cabazitaxel in octogenarian prostate cancer patients

Background

To evaluate the effectiveness and safety of cabazitaxel in castration-resistant prostate cancer patients aged ≥80 years, we performed a retrospective study on a sample of patients from 11 Italian cancer centers.

Materials and methods

Fifty-seven patients aged ≥80 years were treated with cabazitaxel after previous failure with docetaxel; 39 completed a comprehensive geriatric assessment questionnaire (34 fit and 5 vulnerable) and 8 patients (14%) had an Eastern Cooperative Oncology Group performance status (PS) ≥2, while most had a PS of 0-1 (86%). Cabazitaxel was administered at a dose of 25 mg/m2 in 30 (52%) patients and 20 mg/m2 or adapted schedules in 27 (48%) patients. These schedules were adopted mainly in patients ≥85 years (75%), with a PS ≥2 (87.5%), and those classified as vulnerable (100%).

Results

The duration of treatment was 4.8 months and was comparable in all subgroups; disease control rate was reported in 36 patients (63%); prostate-specific antigen response was recorded in 18 patients (31.5%). Median overall survival was 13.1 months regardless of age (<85/≥85 years), but overall survival was reduced in vulnerable (7.2 months) and PS ≥ 2 patients (6.8 months). The most frequently documented grade 3-4 toxicities were neutropenia (14%) and diarrhea (10.5%). Six patients (10.5%) dropped out due to severe toxicity.

Conclusions

Octogenarian patients can be treated with cabazitaxel with reduced doses or alternative schedules that are associated with less toxicity and fewer treatment interruptions. Comprehensive geriatric assessment could facilitate more appropriate patient selection.

Safety and Efficacy of [177Lu]-PSMA-I&T Radioligand Therapy in Octogenarians with Metastatic Castration-Resistant Prostate Cancer: Report on 80 Patients over the Age of 80 Years

¹⁷⁷Lu-labeled prostate-specific membrane antigen (PSMA) radioligand therapy (RLT) is a new treatment option for metastatic castration-resistant prostate cancer (mCRPC). Its low toxicity profile favors use in elderly patients or in patients with critical comorbidities. The purpose of this analysis was to evaluate the efficacy and safety of [¹⁷⁷Lu]-PSMA RLT in mCRPC patients at least 80 y old. Methods: Eighty mCRPC patients at least 80 y old underwent [¹⁷⁷Lu]-PSMA-I&T RLT and were retrospectively selected. The patients were previously treated by androgen receptor-directed therapy, received taxane-based chemotherapy, or were chemotherapy-ineligible. The best prostate-specific antigen (PSA) response was calculated, as well as clinical progression-free survival (cPFS) and overall survival (OS). Toxicity data were acquired until 6 mo after the last treatment cycle. Results: Of 80 patients, 49 (61.3%) were chemotherapy-naïve and 16 (20%) had visceral metastases. The median number of previous mCRPC treatment regimens was 2. In total, 324 cycles (median, 4 cycles; range, 1-12) with a median cumulative activity of 23.8 GBq (interquartile range, 14.8-42.2) were applied. A PSA decline of 50% was achieved in 37 (46.3%) patients. Chemotherapy-naïve patients showed higher 50% PSA response rates than chemotherapy-pretreated patients (51.0% vs. 38.7%, respectively). Overall, median cPFS and OS were 8.7 and 16.1 mo, respectively. The median cPFS and OS of chemotherapy-naïve patients were significantly longer than those of chemotherapy-pretreated patients (10.5 vs. 6.5 mo and 20.7 vs. 11.8 mo, respectively, P < 0.05). A lower hemoglobin level and higher lactate dehydrogenase level at baseline were independent predictors of shorter cPFS and OS. Treatment-emergent grade 3 toxicities were anemia in 4 patients (5%), thrombocytopenia in 3 patients (3.8%), and renal impairment in 4 patients (5%). No nonhematologic grade 3 and no grade 4 toxicities were observed. The most frequent clinical side effects were grade 1-2 xerostomia, fatigue, and inappetence. Conclusion: [¹⁷⁷Lu]-PSMA-I&T RLT in mCRPC patients at least 80 y old is safe and effective, comparable to previously published data on non-age-selected cohorts with a low rate of high-grade toxicities. Chemotherapy-naïve patients showed a better and longer response to therapy than taxane-pretreated patients. [¹⁷⁷Lu]-PSMA RLT seems to be a meaningful treatment option for older patients.

Results from Expanded Access Programs: A Review of Academic Literature

BACKGROUND

Although expanded access is an increasingly used pathway for patients to access investigational medicine, little is known on the magnitude and content of published scientific research collected via expanded access.

METHODS

We performed a review of all peer-reviewed expanded access publications between January 1, 2000 and January 1, 2022. We analyzed the publications for drugs, diseases, disease area, patient numbers, time, geographical location, subject, and research methodology (single center/multicenter, international/national, prospective/retrospective). We additionally analyzed endpoints reported in all COVID-19-related expanded access publications.

RESULTS

We screened 3810 articles and included 1231, describing 523 drugs for 354 diseases for 507,481 patients. The number of publications significantly increased over time ([Formula: see text]). Large geographical disparities existed as Europe and the Americas accounted for 87.4% of all publications, whereas Africa only accounted for 0.6%. Oncology and hematology accounted for 53% of all publications. Twenty-nine percent of all expanded access patients (N = 197,187) reported on in 2020 and 2021 were treated in the context of COVID-19.

CONCLUSIONS

By summarizing characteristics of patients, diseases, and research methods described in all scientific literature published on expanded access, we provide a unique dataset for future research. We show that published scientific research on expanded access has surged over the past decades, partly due to COVID-19. However, international collaboration and equity in geographic access remain an issue of concern. Lastly, we stress the need for harmonization of research legislation and guidance on the value of expanded access data within real-world data frameworks to improve equity in patient access and streamline future expanded access research.

Cabazitaxel's ototoxicity: An animal study and histopathologic research

Introduction

Chemotherapeutic agents can have both serious side effects and ototoxicity, which can be caused by direct toxic effects or by metabolic derangement by the agents. Cabazitaxel (CBZ) is a next-generation semi-synthetic taxane derivative that is effective in both preclinical models of human tumors that are sensitive or resistant to chemotherapy and in patients suffering from progressive prostate cancer despite docetaxel treatment. The primary aim of this study is to investigate the ototoxicity of CBZ in a rat model.

Materials and Methods

: A total of 24 adult male Wistar-Albino rats were equally and randomly divided into four groups. CBZ (Jevtana, Sanofi-Aventis USA) was intraperitoneally administered to Groups 2, 3, and 4 at doses of 0.5, 1.0, and 1.5 mg/kg/week, respectively, for 4 consecutive weeks; Group 1 received only i.p. saline at the same time. At the end of the study, the animals were sacrificed and their cochlea removed for histopathological examination.

Results

: Intraperitoneal administration of CBZ exerted an ototoxic effect on rats, and the histopathological results became worse in a dose-dependent manner (P < 0.05).

Conclusion

: Our findings suggest that CBZ may be an ototoxic agent and can damage the cochlea. More clinical studies should be conducted to understand its ototoxicity.

Generating Evidence from Expanded Access Use of Rare Disease Medicines: Challenges and Recommendations

Patients with rare diseases often have limited or no options for approved treatments or participation in clinical trials. In such cases, expanded access (or “compassionate use”) provides a potential means of accessing unapproved investigational medicines. It is also possible to capture and analyze clinical data from such use, but doing so is controversial. In this perspective, we offer examples of evidence derived from expanded access programs for rare diseases to illustrate its potential value to the decision-making of regulators and payers in the European Union and the United States. We discuss ethical and regulatory aspects to the use of expanded access data, with a focus on rare disease medicines. The heterogeneous approach to expanded access among countries within the European Union leaves uncertainties to what extent data can be collected and analyzed. We recommend the issuance of new guidance on data collection during expanded access, harmonization of European pathways, and an update of existing European compassionate use guidance. We hereby aim to clarify the supportive role of expanded access in evidence generation. Harmonization across Europe of expanded access regulations could reduce manufacturer burdens, improve patient access, and yield better data. These changes would better balance the need to generate quality evidence with the desire for pre-approval access to investigational medicine.

Management of prostate cancer in older patients

The incidence of prostate cancer among older men has increased in many countries, including Asian countries. However, older patients are ineligible for inclusion in large randomized trials, and the existing guidelines for the management of patients with prostate cancer do not provide specific treatment recommendations for older men. Therefore, generation of evidence for older patients with prostate cancer is a key imperative. The International Society of Geriatric Oncology has produced and updated several guidelines for management of prostate cancer in older men since 2010. Regarding localized prostate cancer, both surgery and radiotherapy are considered as feasible treatment options for intermediate- and high-risk prostate cancer even in older men, whereas watchful waiting and active surveillance are useful options for a proportion of these patients. With regard to advanced disease, androgen-receptor axis targets and taxane chemotherapy are standard treatment modalities, although dose modification and prevention of adverse events need to be considered. Management strategy for older patients with prostate cancer should take cognizance of not only the chronological age but also psychological and physical condition, socio-economic status and patient preferences. Geriatric assessment and patient-reported health-related quality of life are important tools for assessing health status of older patients with prostate cancer; however, there is a paucity of evidence of the impact of these tools on the clinical outcomes. Personalized management according to the patient's health status and tumour characteristics as well as socio-economic condition may be necessary for treatment of older patients with prostate cancer.

Efficacy and Safety of Cabazitaxel Versus Abiraterone or Enzalutamide in Older Patients with Metastatic Castration-resistant Prostate Cancer in the CARD Study

BACKGROUND

In the CARD study (NCT02485691), cabazitaxel significantly improved median radiographic progression-free survival (rPFS) and overall survival (OS) versus abiraterone/enzalutamide in patients with metastatic castration-resistant prostate cancer (mCRPC) who had previously received docetaxel and progressed ≤12 mo on the alternative agent (abiraterone/enzalutamide).

OBJECTIVE

To assess cabazitaxel versus abiraterone/enzalutamide in older (≥70 yr) and younger (<70 yr) patients in CARD.

DESIGN, SETTING, AND PARTICIPANTS

Patients with mCRPC were randomized 1:1 to cabazitaxel (25 mg/m² plus prednisone and granulocyte colony-stimulating factor) versus abiraterone (1000 mg plus prednisone) or enzalutamide (160 mg).

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Analyses of rPFS (primary endpoint) and safety by age were prespecified; others were post hoc. Treatment groups were compared using stratified log-rank or Cochran-Mantel-Haenszel tests.

RESULTS AND LIMITATIONS

Of the 255 patients randomized, 135 were aged ≥70 yr (median 76 yr). Cabazitaxel, compared with abiraterone/enzalutamide, significantly improved median rPFS in older (8.2 vs 4.5 mo; hazard ratio [HR] = 0.58; 95% confidence interval [CI] = 0.38-0.89; p = 0.012) and younger (7.4 vs 3.2 mo; HR = 0.47; 95% CI = 0.30-0.74; p < 0.001) patients. The median OS of cabazitaxel versus abiraterone/enzalutamide was 13.9 versus 9.4 mo in older patients (HR = 0.66; 95% CI = 0.41-1.06; p = 0.084), and it was 13.6 versus 11.8 mo in younger patients (HR = 0.66; 95% CI = 0.41-1.08; p = 0.093). Progression-free survival, prostate-specific antigen, and tumor and pain responses favored cabazitaxel, regardless of age. Grade ≥3 treatment-emergent adverse events (TEAEs) occurred in 58% versus 49% of older patients receiving cabazitaxel versus abiraterone/enzalutamide and 48% versus 42% of younger patients. In older patients, cardiac adverse events were more frequent with abiraterone/enzalutamide; asthenia and diarrhea were more frequent with cabazitaxel.

CONCLUSIONS

Cabazitaxel improved efficacy outcomes versus abiraterone/enzalutamide in patients with mCRPC after prior docetaxel and abiraterone/enzalutamide, regardless of age. TEAEs were more frequent among older patients. The cabazitaxel safety profile was manageable across age groups.

PATIENT SUMMARY

Clinical trial data showed that cabazitaxel improved survival versus abiraterone/enzalutamide with manageable side effects in patients with metastatic castration-resistant prostate cancer who had previously received docetaxel and the alternative agent (abiraterone/enzalutamide), irrespective of age.

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.

Establishment of the tandem mass spectrometric fingerprints of taxane-based anticancer compounds

RATIONALE

Compounds in the taxane drug family are among the most successful and effective chemotherapeutic agents used in the treatment of solid tumors, such as breast, ovarian, and prostate cancers. The tandem mass spectrometric (MS/MS) fragmentation behavior of these compounds is described in detail, and a generalized MS/MS fingerprint is established for the first time.

METHODS

Five compounds, namely paclitaxel, docetaxel, cabazitaxel, cephalomannine, and baccatin III, were evaluated. A hybrid quadrupole orthogonal time-of-flight (Q-TOF) mass spectrometer was used to obtain accurate mass measurements, whereas MS/MS and second-generation MS/MS (MS³ ) analyses were performed using a triple quadrupole-linear ion trap mass spectrometer. Both instruments were equipped with an electrospray ionization source operated in the positive ion mode.

RESULTS

All taxanes showed an abundant singly charged [M + H]⁺ species in the single-stage analysis with mass accuracies less than 3 ppm. The evaluated compounds exhibited common fragmentation behavior in their MS/MS analysis, which allowed for the production of a universal fragmentation pattern. MS³ experiments confirmed the genesis of the various product ions proposed in the fragmentation pathway. In addition, diagnostic product ions were originated from a cleavage in the ester bond between the core diterpene ring structure and the side chain.

CONCLUSIONS

Varying functional groups present in these compounds resulted in unique product ions that are specific to each structure. The established MS/MS fingerprints will be used in the near future for identification and for the development of multiple reaction monitoring liquid chromatography-MS/MS quantification methods.

Targeting the glucocorticoid receptor signature gene Mono Amine Oxidase-A enhances the efficacy of chemo- and anti-androgen therapy in advanced prostate cancer

Despite increasing options for treatment of castration-resistant prostate cancer, development of drug resistance is inevitable. The glucocorticoid receptor (GR) is a prime suspect for acquired therapy resistance, as prostate cancer (PCa) cells are able to increase GR signaling during anti-androgen therapy and thereby circumvent androgen receptor (AR)-blockade and cell death. As standard AR-directed therapies fail to block the GR and GR inhibitors might result in intolerable side effects, the identification of GR signature genes, which are better suited for a targeted approach, is of clinical importance. Therefore, the specific epithelial and stromal GR signature was determined in cancer-associated fibroblasts as well as in abiraterone and enzalutamide-resistant cells after glucocorticoid (GC) treatment. Microarray and ChIP analysis identified MAO-A as a directly up-regulated mutual epithelial and stromal GR target, which is induced after GC treatment and during PCa progression. Elevated MAO-A levels were confirmed in in vitro cell models, in primary tissue cultures after GC treatment, and in patients after neoadjuvant chemotherapy with GCs. MAO-A expression correlates with GR/AR activity as well as with a reduced progression-free survival. Pharmacological MAO-A inhibition combined with 2nd generation AR signaling inhibitors or chemotherapeutics results in impaired growth of androgen-dependent, androgen-independent, and long-term anti-androgen-treated cells. In summary, these findings demonstrate that targeting MAO-A represents an innovative therapeutic strategy to synergistically block GR and AR dependent PCa cell growth and thereby overcome therapy resistance.

Cabazitaxel versus abiraterone or enzalutamide in metastatic castration-resistant prostate cancer: post hoc analysis of the CARD study excluding chemohormonal therapy for castrate-naive disease

Background

In the CARD study (NCT02485691), cabazitaxel significantly improved clinical outcomes versus abiraterone or enzalutamide in patients with metastatic castration-resistant prostate cancer previously treated with docetaxel and the alternative androgen-signalling-targeted inhibitor. However, some patients received docetaxel or the prior alternative androgen-signalling-targeted inhibitor in the metastatic hormone-sensitive (mHSPC) setting. Therefore, the CARD results cannot be directly translated to a Japanese population.

Methods

Patients (N = 255) received cabazitaxel (25 mg/m² IV Q3W, prednisone, G-CSF) versus abiraterone (1000 mg PO, prednisone) or enzalutamide (160 mg PO) after prior docetaxel and progression ≤12 months on the alternative androgen-signalling-targeted inhibitor. Patients who received combination therapy for mHSPC were excluded (n = 33) as docetaxel is not approved in this setting in Japan.

Results

A total of 222 patients (median age 70 years) were included in this subanalysis. Median number of cycles was higher for cabazitaxel versus androgen-signalling-targeted inhibitors (7 versus 4). Clinical outcomes favoured cabazitaxel over abiraterone or enzalutamide including, radiographic progression-free survival (rPFS; median 8.2 versus 3.4 months; P < 0.0001), overall survival (OS; 13.9 versus 11.8 months; P = 0.0102), PFS (4.4 versus 2.7 months; P < 0.0001), confirmed prostate-specific antigen response (37.0 versus 14.4%; P = 0.0006) and objective tumour response (38.9 versus 11.4%; P = 0.0036). For cabazitaxel versus androgen-signalling-targeted inhibitor, grade ≥ 3 adverse events occurred in 55% versus 44% of patients, with adverse events leading to death on study in 2.7% versus 5.7%.

Conclusions

Cabazitaxel significantly improved outcomes including rPFS and OS versus abiraterone or enzalutamide and are reflective of the Japanese patient population. Cabazitaxel should be considered the preferred treatment option over abiraterone or enzalutamide in this setting.

Continuing cabazitaxel beyond 10 cycles for metastatic castrate-resistant prostate cancer: is there a benefit?

AIM

Cabazitaxel prolongs survival in patients with metastatic castration-resistant prostate cancer in the postdocetaxel setting. We investigate the benefit of continuing cabazitaxel beyond 10 cycles in patients who are clinically responding without significant toxicity.

METHODS

A comparison was made between patients who received cabazitaxel for >10 cycles and those who had ≤10 cycles. Overall survival (OS), prostate-specific antigen (PSA) response, alkaline phosphatase (ALP) changes and treatment-associated adverse events were evaluated.

RESULTS

The median OS was 9 months (range 0.75-59), with OS significantly higher in patients who received extended duration of treatment: 14 months (range 3-90) vs 7 months (range 1.3-21) in patients treated with 4-10 cycles (HR 0.28, 95% CI 0.1 to 0.74, p=0.01). PSA decline did not show a significant correlation with OS (PSA decline ≥50%, p=0.54). Furthermore, there was no significant difference in OS between patients who had a normal versus high ALP at baseline. There was no clear evidence of cumulative toxicity in those having >10 cycles.

CONCLUSION

A substantial proportion of patients with metastatic castration-resistant prostate cancer were able to receive more than 10 cycles of cabazitaxel without clinically relevant cumulative toxicity.

Cabazitaxel schedules in metastatic castration-resistant prostate cancer: a review

Cabazitaxel (25 mg/m² every 3 weeks) is the standard second-line chemotherapy for patients with metastatic castration-resistant prostate cancer previously treated with docetaxel. It is associated with a risk of neutropenic complications, which may be a barrier to its use in daily clinical practice, particularly in frail elderly patients. Here the authors reviewed key studies conducted with cabazitaxel (TROPIC, PROSELICA, AFFINITY, CARD and the European compassionate use program) and pilot studies with adapted schedules. Based on this review, the use of prophylactic granulocyte colony-stimulating factor from cycle 1 appears crucial to maximize the benefit-risk ratio of cabazitaxel in metastatic castration-resistant prostate cancer. Preliminary data with alternative schedules look promising, especially for frail patients. Results of the ongoing Phase III CABASTY trial (ClinicalTrials.gov: NCT02961257) are awaited.

Efficacy and safety of cabazitaxel therapy in elderly (≥75 years) patients with castration-resistant prostate cancer: A multiinstitutional study

Background

There is little data on the outcome of cabazitaxel (CBZ) treatment of elderly patients with castration-resistant prostate cancer (CRPC). This study assessed the efficacy and safety of CBZ chemotherapy in patients with CRPC aged 75 years or older in a multiinstitutional study.

Methods

We retrospectively reviewed the 74 patients with CRPC treated with CBZ enrolled in 10 institutions. Clinicopathological backgrounds, prognosis including prostate-specific antigen decline, time to treatment failure, progression-free survival, overall survival, and safety profiles were compared between younger (<75 years) and elder (≥75 years) patients.

Results

In total, 74 patients were enrolled; 50 patients were younger than 75 years and 24 were ≥75 years. Clinicopathological characteristics were comparable between younger and elder patients, with the exception of serum albumin values at the time of CBZ treatment. The median prostate-specific antigen decline in younger and elder men was −8.8% and −32.3% from baseline, respectively. The median time to treatment failure, progression-free survival, and overall survival for younger and elder men were 0.24 and 0.33 years, 0.23 and 0.43 years, and 0.69 and 1.17 years, respectively. In addition, safety profiles were comparable between younger and elder patients.

Conclusions

This multiinstitutional study suggests that patients with CRPC aged 75 years or older eligible for CBZ treatment can be treated safely and with noninferior efficacy compared with those younger than 75 years.

[Treatment of metastatic, castration-resistant prostate cancer]

BACKGROUND

For many decades metastatic, castration-resistant prostate cancer (mCRPC) was thought to be treatment inaccessible. However, today, five drugs with significant life-prolonging effects are available in Germany, namely abiraterone, enzalutamide, docetaxel, cabazitaxel and radium-223.

OBJECTIVE

The different treatment strategies in mCRPC are reviewed.

MATERIALS AND METHODS

Landmark trials with supplementary information from Medline and abstracts of international congresses (ASCO; ASCO GU, ESMO) are summarized.

RESULTS

The androgen receptor (AR)-targeting agents abiraterone and enzalutamide significantly prolong overall survival before and after docetaxel therapy. In addition, cabazitaxel can be applied secondary to docetaxel. Due to the low affinity of cabazitaxel to p‑glycoprotein it remains active even if docetaxel has failed. The α‑emitter radium-223 can be considered in third line therapy for symptomatic patients with bone limited disease only. In patients with castration resistance, a short prostate-specific antigen (PSA) doubling time but without metastases in conventional imaging apalutamide, darolutamide and enzalutamide significantly prolong metastasis-free survival.

DISCUSSION

Prostate-specific membrane antigen (PSMA)-ligand therapy and novel targeting agents such as PARP inhibitors are promising new therapeutic modalities for mCRPC. Combination treatment strategies with immunotherapy are currently being evaluated in clinical trials. Based on the results of molecular analyses of tumor tissue as well as of circulating tumor cells and DNA, treatment of prostate cancer will be increasingly personalized in the future.

Effect of Baseline Characteristics on Cabazitaxel Treatment Duration in Patients with Metastatic Castration-Resistant Prostate Cancer: A Post Hoc Analysis of the Compassionate Use/Expanded Access Programs and CAPRISTANA Registry

We examined factors that may impact cabazitaxel treatment duration in a real-life setting in a compassionate use program, expanded access program, and prospective observational study in metastatic castration-resistant prostate cancer (mCRPC). Patients with mCRPC previously treated with docetaxel (N = 1,621) received cabazitaxel 25 mg/m² intravenously every 3 weeks until disease progression, death, unacceptable toxicity or physician/patient decision. The median number of cabazitaxel cycles was six (range, 1-49); 708 patients (43.7%) received >6 cycles. Patients receiving >6 cycles tended to have a better Eastern Cooperative Oncology Group performance status of 0-1 (p = 0.0017 for ≤6 vs. >6 cycles). Overall, 348 patients (21.5%) were ≥75 years of age; 139 (39.9%) received >6 cycles. The main reason for discontinuation was disease progression; however, in patients receiving 1-2 cycles, the main reason for discontinuation was adverse events. Only 52 patients (3.2%) progressed during cycles 1-2. Cabazitaxel was well tolerated in these studies, which included some elderly and frail patients, offering clinicians an important treatment option in the management of mCRPC. Proactive management of adverse events may allow patients to receive a higher number of cabazitaxel cycles and derive greater benefit.

Cabazitaxel in patients aged ≥80 years with castration-resistant prostate cancer: Results of a post-marketing surveillance study in Japan

OBJECTIVES

Data on the safety and efficacy of cabazitaxel in patients aged ≥80 years with castration-resistant prostate cancer (CRPC) are limited. We report the safety (adverse drug reactions [ADRs]) and efficacy (overall survival [OS], time to treatment failure [TTF], and prostate-specific antigen [PSA] response rates) in patients aged <80 or ≥80 years treated with cabazitaxel for CRPC in clinical practice.

MATERIALS AND METHODS

We performed post-hoc subgroup analyses of a Japanese post-marketing surveillance study involving 662 patients with CRPC treated with cabazitaxel between September 2014 and June 2016.

RESULTS

In patients aged <80 (n = 610) and ≥80 years (n = 49), median PSA at baseline was 168.7 and 109.0 ng/mL, and 86.7% and 83.7% of patients were previously treated with enzalutamide and/or abiraterone. ADRs (all grade) occurred in 77.2% and 79.6% of patients aged <80 and ≥80 years, with grade three/worse ADRs in 61.8% and 63.3% of patients. Hematologic toxicities were the most common grade three/worse ADRs, including neutropenia, febrile neutropenia, and anemia in both subgroups. No specific ADRs were observed in patients aged ≥80 years. The PSA response and median OS and TTF were 28.3%, 292 days, and 116 days in patients aged ≥80 years, and 29.7%, 319 days, and 125 days in patients aged <80 years.

CONCLUSION

Cabazitaxel could be a treatment option for CRPC in patients aged ≥80 years based on its safety and efficacy profiles. This is the first report to investigate the safety and efficacy of cabazitaxel in patients aged ≥80 years with CRPC.

Management of Patients with Advanced Prostate Cancer: Report of the Advanced Prostate Cancer Consensus Conference 2019

BACKGROUND

Innovations in treatments, imaging, and molecular characterisation in advanced prostate cancer have improved outcomes, but there are still many aspects of management that lack high-level evidence to inform clinical practice. The Advanced Prostate Cancer Consensus Conference (APCCC) 2019 addressed some of these topics to supplement guidelines that are based on level 1 evidence.

OBJECTIVE

To present the results from the APCCC 2019.

DESIGN, SETTING, AND PARTICIPANTS

Similar to prior conferences, experts identified 10 important areas of controversy regarding the management of advanced prostate cancer: locally advanced disease, biochemical recurrence after local therapy, treating the primary tumour in the metastatic setting, metastatic hormone-sensitive/naïve prostate cancer, nonmetastatic castration-resistant prostate cancer, metastatic castration-resistant prostate cancer, bone health and bone metastases, molecular characterisation of tissue and blood, inter- and intrapatient heterogeneity, and adverse effects of hormonal therapy and their management. A panel of 72 international prostate cancer experts developed the programme and the consensus questions.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The panel voted publicly but anonymously on 123 predefined questions, which were developed by both voting and nonvoting panel members prior to the conference following a modified Delphi process.

RESULTS AND LIMITATIONS

Panellists voted based on their opinions rather than a standard literature review or formal meta-analysis. The answer options for the consensus questions had varying degrees of support by the panel, as reflected in this article and the detailed voting results reported in the Supplementary material.

CONCLUSIONS

These voting results from a panel of prostate cancer experts can help clinicians and patients navigate controversial areas of advanced prostate management for which high-level evidence is sparse. However, diagnostic and treatment decisions should always be individualised based on patient-specific factors, such as disease extent and location, prior lines of therapy, comorbidities, and treatment preferences, together with current and emerging clinical evidence and logistic and economic constraints. Clinical trial enrolment for men with advanced prostate cancer should be strongly encouraged. Importantly, APCCC 2019 once again identified important questions that merit assessment in specifically designed trials.

PATIENT SUMMARY

The Advanced Prostate Cancer Consensus Conference provides a forum to discuss and debate current diagnostic and treatment options for patients with advanced prostate cancer. The conference, which has been held three times since 2015, aims to share the knowledge of world experts in prostate cancer management with health care providers worldwide. At the end of the conference, an expert panel discusses and votes on predefined consensus questions that target the most clinically relevant areas of advanced prostate cancer treatment. The results of the voting provide a practical guide to help clinicians discuss therapeutic options with patients as part of shared and multidisciplinary decision making.

Cabazitaxel versus Abiraterone or Enzalutamide in Metastatic Prostate Cancer

BACKGROUND

The efficacy and safety of cabazitaxel, as compared with an androgen-signaling-targeted inhibitor (abiraterone or enzalutamide), in patients with metastatic castration-resistant prostate cancer who were previously treated with docetaxel and had progression within 12 months while receiving the alternative inhibitor (abiraterone or enzalutamide) are unclear.

METHODS

We randomly assigned, in a 1:1 ratio, patients who had previously received docetaxel and an androgen-signaling-targeted inhibitor (abiraterone or enzalutamide) to receive cabazitaxel (at a dose of 25 mg per square meter of body-surface area intravenously every 3 weeks, plus prednisone daily and granulocyte colony-stimulating factor) or the other androgen-signaling-targeted inhibitor (either 1000 mg of abiraterone plus prednisone daily or 160 mg of enzalutamide daily). The primary end point was imaging-based progression-free survival. Secondary end points of survival, response, and safety were assessed.

RESULTS

A total of 255 patients underwent randomization. After a median follow-up of 9.2 months, imaging-based progression or death was reported in 95 of 129 patients (73.6%) in the cabazitaxel group, as compared with 101 of 126 patients (80.2%) in the group that received an androgen-signaling-targeted inhibitor (hazard ratio, 0.54; 95% confidence interval [CI], 0.40 to 0.73; P<0.001). The median imaging-based progression-free survival was 8.0 months with cabazitaxel and 3.7 months with the androgen-signaling-targeted inhibitor. The median overall survival was 13.6 months with cabazitaxel and 11.0 months with the androgen-signaling-targeted inhibitor (hazard ratio for death, 0.64; 95% CI, 0.46 to 0.89; P = 0.008). The median progression-free survival was 4.4 months with cabazitaxel and 2.7 months with an androgen-signaling-targeted inhibitor (hazard ratio for progression or death, 0.52; 95% CI, 0.40 to 0.68; P<0.001), a prostate-specific antigen response occurred in 35.7% and 13.5% of the patients, respectively (P<0.001), and tumor response was noted in 36.5% and 11.5% (P = 0.004). Adverse events of grade 3 or higher occurred in 56.3% of patients receiving cabazitaxel and in 52.4% of those receiving an androgen-signaling-targeted inhibitor. No new safety signals were observed.

CONCLUSIONS

Cabazitaxel significantly improved a number of clinical outcomes, as compared with the androgen-signaling-targeted inhibitor (abiraterone or enzalutamide), in patients with metastatic castration-resistant prostate cancer who had been previously treated with docetaxel and the alternative androgen-signaling-targeted agent (abiraterone or enzalutamide). (Funded by Sanofi; CARD ClinicalTrials.gov number, NCT02485691.).

[Geriatric specificities of prostate cancer]

PURPOSE

To describe the epidemiology of prostate cancer (PCa) and its natural history in the elderly patient. To propose adaptations of geriatric evaluation specific to PCa. Recall therapeutic options and the treatment options specific to elderly patients.

METHOD

Bibliographic research from the Medline bibliographic database (NLM Pubmed tool) and Embase, as well as on the websites of scientific societies of geriatrics, from the National Cancer Institute using the following keywords: elderly, geriatrics, prostate cancer, diagnosis, treatment.

RESULTS

The median age at diagnosis for PCa is 69 years old, making PCa the very type of cancer of the elderly. The specific mortality of the disease increases with age. This translates two of its characteristics. First, a diagnosis at higher grade and stage is more common in older patients than in younger patients. Secondly, use of curative therapeutic options is less common in elderly patients than in younger patients. SIOG recommends a specific geriatric assessment for patients with PCa, which may be useful, but the need for an initial detection of cognitive disorders is open to criticism. There is no therapeutic trial, if only prospective, dedicated to elderly patients with PCa. However, decision-making in the elderly patient with PCa must pursue two goals: first, the respect of the expectations specific to each patient and secondly, the search for the global clinical benefit; goals that should not be restricted to elderly patients.

CONCLUSION

PCa in the elderly patient follow the current guidelines for diagnostic and for treatment. Compliance with these guidelines should eliminate both the late diagnosis and the under-treatment actually observed.

Overall and progression-free survival with cabazitaxel in metastatic castration-resistant prostate cancer in routine clinical practice: the FUJI cohort

Background

Cabazitaxel is a treatment of metastatic castration-resistant prostate cancer (mCRPC) after docetaxel failure. The FUJI cohort aimed to confirm the real-life overall and progression-free survival (OS, PFS) and safety of cabazitaxel.

Methods

Multicentre, non-interventional cohort of French mCRPC patients initiating cabazitaxel between 2013 and 2015, followed 18 months.

Results

Four hundred one patients were recruited in 42 centres. At inclusion, median age was 70, main metastatic sites were bones (87%), lymph nodes (42%) and visceral (20%). 18% had cabazitaxel in 2nd-line treatment, 39% in 3rd-line and 43% in 4th-line or beyond. All had prior docetaxel, and 82% prior abiraterone, enzalutamide or both. Median duration of cabazitaxel treatment was 3.4 months. Median OS from cabazitaxel initiation was 11.9 months [95% CI: 10.1–12.9]. In multivariate analyses, grade ≥ 3 adverse events, visceral metastases, polymedication, and >5 bone metastases were associated with a shorter OS. Main grade ≥ 3 adverse events were haematological with 8% febrile neutropenia.

Conclusion

Real-life survival with cabazitaxel in FUJI was shorter than in TROPIC (pivotal trial, median OS 15.1 months) or PROSELICA (clinical trial 20 vs 25 mg/m², median OS, respectively, 13.4 and 14.5 months). There was no effect of treatment-line on survival. No unexpected adverse concerns were identified.

Study registration

It was registered with the European Medicines Agency EUPASS registry, available at www.encepp.eu, as EUPAS10391. It has been approved as an ENCEPP SEAL study.

Real-world experience with cabazitaxel in patients with metastatic castration-resistant prostate cancer: a final, pooled analysis of the compassionate use programme and early access programme

BACKGROUND

Cabazitaxel is a second-generation taxane approved for use in patients with metastatic castration-resistant prostate cancer (mCRPC) previously treated with docetaxel. Early access programmes were established to allow eligible patients with mCRPC access to cabazitaxel before regulatory approval.

MATERIALS AND METHODS

The primary objective was to allow access to cabazitaxel before commercial availability for patients with mCRPC whose disease had progressed during or after chemotherapy with docetaxel; the secondary objective was overall safety. Patients received cabazitaxel 25 mg/m² on Day 1 of a 21-day cycle, with daily oral 10 mg prednisone/prednisolone. G-CSF was administered per ASCO guidelines.

RESULTS

In total, 1432 patients received cabazitaxel across 41 countries between 2010 and 2014 (median 6.0 treatment cycles [range 1-49]). The most frequently occurring treatment-emergent adverse events (TEAEs) possibly related to treatment were diarrhoea (33.3%), fatigue (25.4%) and anaemia (23.7%); the most frequently occurring possibly related Grade 3/4 TEAEs were neutropenia (18.7%) and febrile neutropenia (6.9%). G-CSF was administered in ≥ 1 cycle in 64% of patients (10.1% therapeutic use; 57.8% prophylactic use; 9.7% both uses).

CONCLUSION

The safety profile of cabazitaxel in this pooled analysis of two cabazitaxel early access programmes was manageable and consistent with previous Phase III trials (TROPIC, PROSELICA).

Combination of cabazitaxel and p53 gene therapy abolishes prostate carcinoma tumor growth

For patients with metastatic prostate cancer, the 5-year survival rate of 31% points to a need for novel therapies and improvement of existing modalities. We propose that p53 gene therapy and chemotherapy, when combined, will provide superior tumor cell killing for the treatment of prostate carcinoma. To this end, we have developed the AdRGD-PGp53 vector which offers autoregulated expression of p53, resulting in enhanced tumor cell killing in vitro and in vivo. Here, we combined AdRGD-PGp53 along with the chemotherapy drugs used in the clinical treatment of prostate carcinoma, mitoxantrone, docetaxel, or cabazitaxel. Our results indicate that all drugs increase phosphorylation of p53, leading to improved induction of p53 targets. In vitro experiments reveal that AdRGD-PGp53 sensitizes prostate cancer cells to each of the drugs tested, conferring increased levels of cell death. In a xenograft mouse model of in situ gene therapy, AdRGD-PGp53 treatment, when combined with cabazitaxel, drastically reduced tumor progression and increased survival rates to 100%. Strikingly, we used a sub-therapeutic dose of cabazitaxel thus avoiding leukopenia, yet still showed potent anti-tumor effects when combined with AdRGD-PGp53 in this mouse model. The AdRGD-PGp53 approach warrants further development for its application in gene therapy of prostate carcinoma.

[Concepts in geriatric uro-oncology]

Uro-oncology is not only concerned with treatment methods themselves but also with therapeutic objectives and decision-making concepts involving algorithms. We discuss whether the latter is applicable to all patients groups or needs to be adapted in order to be suitable for elderly and frail patients with regard to their lifestyle and living situation as well as their altered physiology.

No significant impact of patient age and prior treatment profile with docetaxel on the efficacy of cabazitaxel in patient with castration-resistant prostate cancer

BACKGROUND

The correlation of the oncological outcomes of docetaxel and cabazitaxel in Japanese metastatic castration-resistant prostate cancer (mCRPC) patients has not been unclear.

MATERIALS AND METHODS

This study included a total of 47 consecutive Japanese mCRPC patients treated with cabazitaxel and assessed the prognostic significance of cabazitaxel, focusing on patient age and the correlation of efficacy between docetaxel and cabazitaxel.

RESULTS

Prostate-specific antigen (PSA) decline was observed in 27 patients (57.4%), including 19 (40.0%) achieving the response defined by PSA decline ≥ 30%. The median overall survival (OS) periods after the introduction of cabazitaxel was 16.1 months. Twenty (42.6%) were judged to have responded to cabazitaxel with a PSA decrease ≥ 30% from the baseline. A 30% PSA response to cabazitaxel was achieved in 4 (50.0%) patients with ≧ 75 years (n = 8) and 16 (41.0%) patients with less than 75 years (n = 39). There was no significant correlation between the PSA response and patients' age (p = 0.707). A 30% PSA response to cabazitaxel was achieved in 13 (46.4%) and 7 (36.8%) patients with and without that to docetaxel, respectively. A 30% PSA response to cabazitaxel was achieved in 5 (16.6%) and 7 (41.2%) patients who had treated with less than 10 cycles docetaxel or 10 ≦ cycles, respectively. Univariate and multivariate analyses revealed that there were no significant correlation of patient age (p = 0.537), the response to prior docetaxel therapy (p = 0.339) or cycles of docetaxel therapy (p = 0.379) with shorter OS.

CONCLUSION

These results indicate that the introduction of cabazitaxel for Japanese mCRPC patients could result in oncological outcomes without any association with patient's age and the profiles of previous docetaxel therapy.

Sequencing of Taxanes and New Androgen-targeted Therapies in Metastatic Castration-resistant Prostate Cancer: Results of the International Multicentre Retrospective CATS Database

BACKGROUND

The optimal sequence of life-extending therapies in metastatic castration-resistant prostate cancer (mCRPC) is unknown.

OBJECTIVE

To evaluate outcomes among mCRPC patients treated with docetaxel (DOC), cabazitaxel (CABA), and a novel androgen receptor-targeted agent (ART; abiraterone acetate or enzalutamide) according to three different sequences.

DESIGN, SETTING, AND PARTICIPANTS

Data from 669 consecutive mCRPC patients were retrospectively collected between November 2012 and October 2016.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The primary endpoint was the prostate-specific antigen (PSA) response (decrease ≥50% from baseline) to each therapy. Secondary endpoints included best clinical benefit, time to PSA progression, radiological progression-free survival (rPFS), overall survival (OS), and toxicity.

RESULTS AND LIMITATIONS

A total of 158 patients received DOC→CABA→ART (group 1), 456 received DOC→ART→CABA (group 2), and 55 received ART→DOC→CABA (group 3). At baseline, PSA progression only and Gleason <8 were more common in group 3. PSA response on DOC was lower in group 3 than in other groups (p=0.02) and PSA response on CABA was higher in the second than in the third line (p=0.001). In Group 3, rPFS on ART (6.6 mo) and DOC (9.2 mo) was also shorter than in the other groups. OS calculated from the first life-extending therapy reached 34.8, 35.8, and 28.9 mo in groups 1, 2 and 3, respectively (p=0.007). Toxicity was comparable between the arms. The main limitations of the trial are its retrospective design and the low number of patients in group 3.

CONCLUSIONS

In this retrospective trial, sequencing of DOC, CABA, and one ART, was associated with median OS of up to 35.8 mo. CABA seemed to retain its activity regardless of treatment sequence. DOC activity after ART appeared to be reduced, but the data are insufficient to conclude that cross-resistance occurs.

PATIENT SUMMARY

The order of drugs administered to patients with metastatic castration-resistant prostate cancer could impact their efficacy, with cabazitaxel appearing to retain its activity whatever the therapeutic sequence.

Interrogating Metastatic Prostate Cancer Treatment Switch Decisions: A Multi-institutional Survey

BACKGROUND

Evaluation of responses to treatment for metastatic castration-resistant prostate cancer (mCRPC) remains challenging. Consensus criteria based on prostate-specific antigen (PSA) and clinical and radiologic biomarkers are inconsistently utilized. Circulating tumor cell (CTC) counts can inform prognosis and response, but are not routinely used.

OBJECTIVE

To evaluate the use of biomarkers and trends in clinical decision-making in current mCRPC treatment.

DESIGN, SETTING, AND PARTICIPANTS

A 23-part online questionnaire was completed by physicians treating mCRPC.

OUTCOME MEASURES AND STATISTICAL ANALYSIS

Results are presented as the proportion (%) of physicians responding to each of the options. We used χ2 and Fisher's tests to compare differences.

RESULTS AND LIMITATIONS

A total of 118 physicians (22.1%) responded. Of these, 69.4% treated ≥50 mCRPC patients/year. More physicians administered four or fewer courses of cabazitaxel (27.9%) than for docetaxel (10.4%), with no significant difference in the number of courses between bone-only disease and Response Evaluation Criteria in Solid Tumours (RECIST)-evaluable disease. Some 74.5% of respondents considered current biomarkers useful for monitoring disease, but only 39.6% used the Prostate Cancer Working Group (PCWG2) criteria in clinical practice. PSA was considered an important biomarker by 55.7%, but only 41.4% discarded changes in PSA before 12 wk, and only 39.4% were able to identify bone-scan progression according to PCWG2. The vast majority of physicians (90.5%) considered clinical progression to be important for switching treatment. The proportion considering biomarkers important was 71.6% for RECIST, 47.4% for bone scans, 23.2% for CTCs, and 21.1% for PSA. Although 53.1% acknowledged that baseline CTC counts are prognostic, only 33.7% would use CTC changes alone to switch treatment in patients with bone-only disease. The main challenges in using CTC counts were access to CTC technology (84.7%), cost (74.5%), and uncertainty over utility as a response indicator (58.2%).

CONCLUSIONS

A significant proportion of physicians discontinue treatment for mCRPC before 12 wk, raising concerns about inadequate response assessment. Many physicians find current biomarkers useful, but most rely on symptoms to drive treatment switch decisions, suggesting there is a need for more precise biomarkers.

PATIENT SUMMARY

In this report we analyse the results of a questionnaire evaluating tools for clinical decision-making completed by 118 prostate cancer specialists. We found that most physicians favour clinical progression over prostate-specific antigen or imaging, and that criteria established by the Prostate Cancer Working Group are not widely used.

The Glucocorticoid Receptor Is a Key Player for Prostate Cancer Cell Survival and a Target for Improved Antiandrogen Therapy

Purpose: The major obstacle in the management of advanced prostate cancer is the occurrence of resistance to endocrine therapy. Although the androgen receptor (AR) has been linked to therapy failure, the underlying escape mechanisms have not been fully clarified. Being closely related to the AR, the glucocorticoid receptor (GR) has been suggested to play a role in enzalutamide and docetaxel resistance. Given that glucocorticoids are frequently applied to prostate cancer patients, it is essential to unravel the exact role of the GR in prostate cancer progression.Experimental Design: Assessment of GR expression and functional significance in tissues from 177 prostate cancer patients, including 14 lymph node metastases, as well as in several human prostate cancer models, including androgen-dependent, androgen-independent, and long-term antiandrogen-treated cell lines.Results: Although GR expression is reduced in primary prostate cancer tissue, it is restored in metastatic lesions. Relapse patients with high GR experience shortened progression-free survival. GR is significantly increased upon long-term abiraterone or enzalutamide treatment in the majority of preclinical models, thus identifying GR upregulation as an underlying mechanism for cells to bypass AR blockade. Importantly, GR inhibition by RNAi or chemical blockade results in impaired proliferation and 3D-spheroid formation in all tested cell lines.Conclusions: GR upregulation seems to be a common mechanism during antiandrogen treatment and supports the notion that targeting the GR pathway combined with antiandrogen medication may further improve prostate cancer therapy. Clin Cancer Res; 24(4); 927-38. ©2017 AACR.

Efficacy and safety of post-docetaxel therapies in metastatic castration-resistant prostate cancer: a systematic review of the literature

OBJECTIVE

Prostate cancer is a highly prevalent form of cancer in older men and is one of the leading causes of death from cancer in men across the globe. Many therapeutic agents have been approved for patients with metastatic castration-resistant prostate cancer (mCRPC), particularly as a post-docetaxel treatment strategy. The objective of this systematic literature review was to assess published efficacy and safety data for select mCRPC therapies - such as abiraterone, cabazitaxel, and enzalutamide - in the post-docetaxel setting.

METHODS

Database searches of MEDLINE, Embase, and Cochrane CENTRAL, in conjunction with hand searches of multiple congress abstracts, yielded 13 randomized studies and 107 non-randomized studies that met the inclusion criteria.

RESULTS

Randomized studies demonstrated significant improvements in median overall survival (OS) outcomes over placebo for abiraterone (15.8 vs. 11.2 months) and enzalutamide (18.4 vs. 13.6 months), and similar significant improvements were noted for cabazitaxel over mitoxantrone (15.1 vs. 12.7 months). Differences in progression-free survival (PFS) were similarly significant, although variance in the criteria for measuring PFS may limit the extent to which these outcomes can be compared between studies. Non-randomized evidence included multiple publications from several early access and compassionate use programs with a primary objective to report safety outcomes. Results from these studies largely reflected the findings in randomized trials.

CONCLUSIONS

Overall, there is a growing body of evidence for post-docetaxel treatment options available in patients with mCRPC. Further head-to-head trials or indirect treatment comparisons may be a valuable method to assess the comparative efficacy of these therapies.

[Metastatic castration-resistant prostate cancer : Use of cabazitaxel taking into consideration current data]

BACKGROUND

At the 2016 ASCO annual meeting, new data from two randomized phase III studies concerning taxane-based chemotherapy as a treatment option for patients with metastatic castration-resistant prostate cancer (mCRPC) were presented.

OBJECTIVES

The focus is on the clinical impact of these data.

MATERIALS AND METHODS

A group of German experts in the field of urogenital-oncologic expertise discussed the clinical impact with respect to the current data.

RESULTS

The study results support the current clinical data. They confirm the efficacy and safety of cabazitaxel beyond first-line therapy with docetaxel for patients with mCRPC.

CONCLUSIONS

Cabazitaxel is an important treatment option after docetaxel progression. With respect to the performance status of a patient, it is adequate to reduce the dosage to 20 mg/m² cabazitaxel.

Quality of Life in Second-Line Treatment of Metastatic Castration-Resistant Prostate Cancer Using Cabazitaxel or Other Therapies After Previous Docetaxel Chemotherapy: Swiss Observational Treatment Registry

BACKGROUND

The aim was to evaluate quality of life (QoL), pain, and fatigue in patients with metastatic castration-resistant prostate cancer (mCRPC) treated with different regimens after first-line docetaxel, as well as disease progression.

PATIENTS AND METHODS

Patients with mCRPC having received first-line chemotherapy with docetaxel were eligible. Second-line treatment choice was at the discretion of the local investigator. All patients had regular assessments of QoL with the Functional Assessment of Cancer Therapy-Prostate (FACT-P) questionnaire, of fatigue with the Brief Fatigue Inventory, and of pain with the McGill Pain Questionnaire-Short Form. The primary end point was QoL maintenance defined as having a maximum decrease in 2 functional domains of the FACT-P.

RESULTS

One hundred thirty-eight patients were included in 36 oncology centers across Switzerland. QoL analysis was available for all patients (59 who received cabazitaxel; 79 who received other therapy [OT] including 75 who received abiraterone). No significant differences for any of the end points were found between groups. A numerically higher number of patients had QoL maintenance with OT (25 of 79 patients, 32%) compared with cabazitaxel (8 of 59 patients, 14%). QoL improvement was found in 20% of patients (12 of 59) who received cabazitaxel and 24% (19 of 79) who received OT. Mean FACT-P score did not change in a clinically relevant manner over time in either group. Pain was present in 70% of patients (96 of 138), and a pain response to treatment was noted in 22% (13 of 59) who received cabazitaxel and 29% (23 of 79) who received OT. A similar but minor improvement of fatigue was noted in both groups.

CONCLUSION

Some degree of QoL decrease was seen in most patients regardless of second-line treatment. No significant differences in QoL parameters between cabazitaxel or other second line treatments were found.

Cabazitaxel in the treatment of metastatic castration-resistant prostate cancer: patient selection and special considerations

Cabazitaxel is an effective chemotherapeutic agent used in the treatment of metastatic castration-resistant prostate cancer (mCRPC) refractory to docetaxel. With the advent of new antiandrogen therapies, immune-based treatments, and radioactive-targeted therapy, there are now multiple effective and approved agents for this disease state. The optimal sequencing of these agents is unclear as there are no large-scale head-to-head comparisons. Clinicians must familiarize themselves with the most recent studies as well as drug toxicities to determine the best treatment option for their patients. In this review, we focus on the development of cabazitaxel for mCRPC, evaluate its efficacy, and highlight key strategies for toxicity management. Additionally, we summarize the studies that address cabazitaxel treatment sequencing and optimal dosing schedule.

Dose considerations for anti-cancer drugs in metastatic prostate cancer

Despite a growing number of treatment options, metastatic castrate resistant prostate cancer remains almost universally fatal. Dose individualization ensures patients receive the maximal benefit from each line of treatment potentially leading to improved outcomes, a reduction in quality of life impairment and minimization of premature cessation for avoidable toxicity. Herein, we review drug-specific issues that may be associated with unexpected or unrecognized variations in drug systemic exposure despite the use of protocol doses. In particular, we discuss the potential for under-exposure of docetaxel and cabazitaxel; over-exposure of enzalutamide; and varied absorption of abiraterone acetate.

Cabazitaxel in patients with metastatic castration-resistant prostate cancer: safety and quality of life data from the Australian early access program

AIM

Cabazitaxel is a next generation taxane that has been shown to improve overall survival in patients with metastatic castration-resistant prostate cancer (mCRPC) whose disease progressed during or after docetaxel-based therapy. A worldwide early access program (EAP) study was established to provide access to cabazitaxel ahead of commercial availability and to evaluate its safety and tolerability. The Australian EAP included patient-reported outcomes to evaluate the impact of cabazitaxel on quality of life (QoL). The final safety and QoL results from the Australian EAP for cabazitaxel are reported.

METHODS

Australian patients with mCRPC previously treated with a docetaxel-containing regimen received cabazitaxel (25 mg/m² ) every 3 weeks plus prednisone/prednisolone (10 mg daily) until disease progression, death, unacceptable toxicity, physician's decision or patient's refusal of further treatment. QoL data was collected using the AQoL-8D questionnaire.

RESULTS

104 patients from 18 Australian sites (median age at baseline, 70) enrolled in the EAP and completed at least one AQoL-8D questionnaire. Patients received a median of 6 cycles of cabazitaxel. 67 patients (64.4%) experienced grade ≥3 treatment-emergent adverse events (TEAEs); the most frequent TEAEs were neutropenia, febrile neutropenia, diarrhoea, and vomiting. QoL scores remained stable with increasing treatment cycles.

CONCLUSION

The results suggest that the safety profile cabazitaxel is manageable in the Australian clinical practice setting and that QoL is maintained with little or no detrimental effect of cabazitaxel in patients continuing on treatment without disease progression.

[Advanced Prostate Cancer Consensus Conference (APCCC) 2015 in St. Gallen : Critical review of the recommendations on diagnosis and therapy of metastatic prostate cancer by a German expert panel]

In March 2015, the first Advanced Prostate Cancer Consensus Conference (APCC) took place in St. Gallen. 41 experts from 17 countries reviewed important areas of controversy in advanced hormone-naive and castration-resistant prostate cancer and gave therapy recommendations. These results have been recently published in "Annals of Oncology". While most of the recommendations from St. Gallen are comprehensible, some of them need to be further discussed. Therefore, we as a German expert panel will critically debate the St. Gallen recommendations. For metastatic hormone-naive prostate cancer, continuous androgen deprivation remains the standard. There is no evidence for superiority of primary maximal androgen deprivation. Patients suitable for chemotherapy, especially in the presence of high tumour burden, should receive androgen deprivation plus taxanes upfront. In metastatic castration resistant prostate cancer, novel hormonal agents like abiraterone or enzalutamid should be the treatment of choice in the majority of patients. Taxanes should be used first-line in patients with unfavourable prognostic markers. Radium-223 is an option in symptomatic patients with bone metastases. There is first evidence that second-line hormonal treatment after first-line failure of a novel endocrine agent has a high failure rate. Cabazitaxel should be part of the treatment sequence in patients with a good performance status. Baseline staging for castration-resistant prostate cancer should include CT-abdomen/-chest and bone scan. Radiographic monitoring should be performed 2 to 3 times a year. Determination of PSA and ALP is to take place every 2 to 4 months.

Aged patients with metastatic castration resistant prostate cancer: Should we treat with chemotherapy?

Prostate cancer largely affects aged men and as life expectancy continues to increase, it is likely to be a growing burden requiring an adequate management. Aging is a heterogeneous process, thus, to assess the individual state of health when making decisions is essential. Comprehensive geriatric assessment allows a detailed evaluation of the state of health of a specific subject and can modify the therapeutic decision. It is still not commonly used because it is time consuming. Chemotherapy should be administered equally in aged well-fit patients as in the general population as per the SIOG (International society of geriatric oncology) recommendations for geriatric evaluation and treatment in prostate cancer patients. Chemotherapy with docetaxel or cabazitaxel is expected to have an efficacy and toxicity similar to younger patients and they might be considered treatment options for these patients among others. In vulnerable or frail patients, weekly or biweekly docetaxel regimens are acceptable treatment options.

Cardiovascular toxicities of systemic treatments of prostate cancer

Prostate cancer is the most common cancer in men, with an incidence that is expected to increase in the coming years. Prostate cancer is usually diagnosed in men >65 years of age, thus the concurrent presence of cardiovascular diseases might influence the treatment, owing to the increased risk of cardiovascular mortality. The introduction of new drugs, such as abiraterone and enzalutamide for the management of metastatic disease has created further interest in treatment-related cardiovascular toxicities, although limited data from trials specifically designed to identify cardiovascular toxicities of these agents are currently available. The only available data are derived from published phase II-III study reports, expanded access or compassionate use programmes and meta-analyses of the effects of systemic therapies that are already approved for use in clinical practice or are in the early phases of development. These data are conflicting, although they seem to suggest that certain drugs are associated with an increased risk of cardiovascular adverse events. Clinical trial methodology could be improved by the enrolment of greater numbers of patients >65 years of age, and the use of comprehensive cardiological evaluations. Moreover, closer collaboration between oncologists and cardiologists is essential for the identification and/or management of cardiovascular adverse events in patients with prostate cancer.

Management of Prostate Cancer in Elderly Patients: Recommendations of a Task Force of the International Society of Geriatric Oncology

CONTEXT

Prostate cancer is the most frequent male cancer. Since the median age of diagnosis is 66 yr, many patients require both geriatric and urologic evaluation if treatment is to be tailored to individual circumstances including comorbidities and frailty.

OBJECTIVE

To update the 2014 International Society of Geriatric Oncology (SIOG) guidelines on prostate cancer in men aged >70 yr. The update includes new material on health status evaluation and the treatment of localised, advanced, and castrate-resistant disease.

DATA ACQUISITION

A multidisciplinary SIOG task force reviewed pertinent articles published during 2013-2016 using search terms relevant to prostate cancer, the elderly, geriatric evaluation, local treatments, and castration-refractory/resistant disease. Each member of the group proposed modifications to the previous guidelines. These were collated and circulated. The final manuscript reflects the expert consensus.

DATA SYNTHESIS

Elderly patients should be managed according to their individual health status and not according to age. Fit elderly patients should receive the same treatment as younger patients on the basis of international recommendations. At the initial evaluation, screening for cognitive impairment is mandatory to establish patient competence in making decisions. Initial evaluation of health status should use the validated G8 screening tool. Abnormal scores on the G8 should lead to a simplified geriatric assessment that evaluates comorbid conditions (using the Cumulative Illness Score Rating-Geriatrics scale), dependence (Activities of Daily Living) and nutritional status (via estimation of weight loss). When patients are frail or disabled or have severe comorbidities, a comprehensive geriatric assessment is needed. This may suggest additional geriatric interventions.

CONCLUSIONS

Advances in geriatric evaluation and treatments for localised and advanced disease are contributing to more appropriate management of elderly patients with prostate cancer. A better understanding of the role of active surveillance for less aggressive disease is also contributing to the individualisation of care.

PATIENT SUMMARY

Many men with prostate cancer are elderly. In the physically fit, treatment should be the same as in younger patients. However, some elderly prostate cancer patients are frail and have other medical problems. Treatment in the individual patient should be based on health status and patient preference.