Final quality of life and safety data for patients with metastatic castration-resistant prostate cancer treated with cabazitaxel in the UK Early Access Programme (EAP) (NCT01254279)

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.

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.

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.

Neutropenia Prevention in the Treatment of Post-docetaxel Metastatic, Castration-resistant Prostate Cancer With Cabazitaxel and Prednisone: A Multicenter, Open-label, Single-arm Phase IV Study

INTRODUCTION

Severe neutropenia is a dose-limiting factor that occurs in up to 82% of patients with metastatic castration-resistant prostate cancer (mCRPC) treated with cabazitaxel. This study evaluated the effectiveness of granulocyte colony-stimulating factor (G-CSF) plus ciprofloxacin as prophylaxis in post-docetaxel patients with mCRPC treated with cabazitaxel and at high risk for neutropenia.

PATIENTS AND METHODS

This was a phase IV, multicenter, open-label, single-arm interventional study with men aged ≥ 65 years (or < 65 years and ≥ 25% irradiated bone marrow), presenting with mCRPC after docetaxel failure, performance status ≤ 1, and life expectancy > 12 weeks. Cabazitaxel 25 mg/m² and prednisone were given on day 1, every 21 days. G-CSF was administered on days 2 to 8 of each cycle or until an absolute neutrophil count > 2000/mm³, and ciprofloxacin 1000 mg was given orally on days 5 to 12. The rate of neutropenia grade ≥ 3 during the first cycle (primary endpoint), and frequency of neutropenia grade ≥ 3, febrile neutropenia, diarrhea grade ≥ 3, prostate-specific antigen response, and quality of life during treatment (secondary end points) were estimated.

RESULTS

We included 46 patients. The mean number of cabazitaxel cycles was 9.5. During the first cycle, 40.0% of patients had neutropenia grade ≥ 3, and 42.2% had at least 1 episode of neutropenia during treatment. Febrile neutropenia and diarrhea grade ≥ 3 occurred in 1 patient each. Twenty-nine (64.4%) patients achieved prostate-specific antigen response, and 77.2% improved quality of life scores in at least 1 visit.

CONCLUSIONS

Prophylactic G-CSF was effective in preventing neutropenia grade ≥ 3 and other hematologic complications during treatment with cabazitaxel 25 mg/m² in post-docetaxel patients with mCRPC at high risk for neutropenia. The role of prophyclatic ciprofloxacin to prevent febrile neutropenia in this setting is still unclear and needs to be further evaluated.

Renal and Cardiovascular Toxicities by New Systemic Treatments for Prostate Cancer

Prostate cancer (PC) is the most common male cancer in Western Countries. In recent years, the treatment of relapsed or metastatic disease had benefited by the introduction of a variety of new different drugs. In consideration of the relative long survival of PC patients, side effects of these drugs must be considered and monitored. In this review, we analyzed the newly developed therapies for PC treatment, describing the mechanism of action, the metabolism and latest clinical trials that led to the approval of these drugs in clinical practice. We then evaluated the cardiovascular and renal side effects from pivotal phase III and II studies and meta-analyses. Cardiovascular side effects are the most frequent, in particular hypertension, while renal toxicity is rarer and not well described in literature. Therefore, there is a need to better define the effects of these therapies, in order to personalize patient treatment on the basis of their comorbidities and preferences, in addition to their symptoms and disease load.

Combining anticancer drugs with osteoprotective agents in prostate cancer-A contemporary update

Recently, a plethora of life-prolonging cytotoxic, next-generation hormonal, immunotherapeutical as well as radionuclide therapies has emerged as a standard care for metastasized castration-resistant prostate cancer. Being strikingly effective in cancer control, these novel therapies might in fact exert a beneficial impact on skeletal events. Therefore, combining anticancer drugs with osteoprotective agents might lead to additional clinical advantage but must be weighed against simultaneously exposing patients to serious toxicities. In addition, further survival prolongation by changing treatment paradigm in both metastasized hormone-sensitive and nonmetastatic castration-resistant disease might potentially increase the risk for bone density reduction complications due to a growing efficacy of androgen ablation leading to prolonged exposure. To address both possible indications of combined treatment and to draw practical conclusions, we performed a comprehensive review of the currently available evidence.

Toxicity, Adverse Events, and Quality of Life Associated with the Treatment of Metastatic Castration-Resistant Prostate Cancer

Objectives

Among males, prostate cancer (PCa) is the most common cancer in Europe and the second most common cancer worldwide, especially in those aged > 70 years. With the advent of novel alternative treatments, survival in patients with advanced PCa has increased. PCa is now considered a chronic disease. Survival is an important endpoint in advanced PCa, as is quality of life (QoL). The effects of the disease and its treatment on patient health-related QoL must be taken into account when selecting the most appropriate treatment options. The present literature review aimed to provide an overview of metastatic castration-resistant prostate cancer treatment modalities, with an emphasis on side effect profiles and general health-related QoL.

Methods

PubMed was searched using the keywords metastatic castration-resistant prostate cancer, docetaxel, cabazitaxel, enzalutamide, abiraterone acetate, and QoL.

Conclusion

Based on the studies reviewed herein, abiraterone acetate and enzalutamide provide favorable outcomes, in terms of hematological adverse events. As enzalutamide and abiraterone acetate can be taken orally, they might have a positive effect on patient QoL.

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.

Ormeloxifene Suppresses Prostate Tumor Growth and Metastatic Phenotypes via Inhibition of Oncogenic β-catenin Signaling and EMT Progression

Ormeloxifene is a clinically approved selective estrogen receptor modulator, which has also shown excellent anticancer activity, thus it can be an ideal repurposing pharmacophore. Herein, we report therapeutic effects of ormeloxifene on prostate cancer and elucidate a novel molecular mechanism of its anticancer activity. Ormeloxifene treatment inhibited epithelial-to-mesenchymal transition (EMT) process as evident by repression of N-cadherin, Slug, Snail, vimentin, MMPs (MMP2 and MMP3), β-catenin/TCF-4 transcriptional activity, and induced the expression of pGSK3β. In molecular docking analysis, ormeloxifene showed proficient docking with β-catenin and GSK3β. In addition, ormeloxifene induced apoptosis, inhibited growth and metastatic potential of prostate cancer cells and arrested cell cycle in G₀-G₁ phase via modulation of cell-cycle regulatory proteins (inhibition of Mcl-1, cyclin D1, and CDK4 and induction of p21 and p27). In functional assays, ormeloxifene remarkably reduced tumorigenic, migratory, and invasive potential of prostate cancer cells. In addition, ormeloxifene treatment significantly (P < 0.01) regressed the prostate tumor growth in the xenograft mouse model while administered through intraperitoneal route (250 μg/mouse, three times a week). These molecular effects of ormeloxifene were also observed in excised tumor tissues as shown by immunohistochemistry analysis. Our results, for the first time, demonstrate repurposing potential of ormeloxifene as an anticancer drug for the treatment of advanced stage metastatic prostate cancer through a novel molecular mechanism involving β-catenin and EMT pathway. Mol Cancer Ther; 16(10); 2267-80. ©2017 AACR.

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.

Cabazitaxel for Hormone-Relapsed Metastatic Prostate Cancer Previously Treated With a Docetaxel-Containing Regimen: An Evidence Review Group Perspective of a NICE Single Technology Appraisal

As part of its single technology appraisal (STA) process, the National Institute for Health and Care Excellence (NICE) invited the company that manufactures cabazitaxel (Jevtana^®, Sanofi, UK) to submit evidence for the clinical and cost effectiveness of cabazitaxel for treatment of patients with metastatic hormone-relapsed prostate cancer (mHRPC) previously treated with a docetaxel-containing regimen. The School of Health and Related Research Technology Appraisal Group at the University of Sheffield was commissioned to act as the independent Evidence Review Group (ERG). The ERG produced a critical review of the evidence for the clinical and cost effectiveness of the technology based upon the company's submission to NICE. Clinical evidence for cabazitaxel was derived from a multinational randomised open-label phase III trial (TROPIC) of cabazitaxel plus prednisone or prednisolone compared with mitoxantrone plus prednisone or prednisolone, which was assumed to represent best supportive care. The NICE final scope identified a further three comparators: abiraterone in combination with prednisone or prednisolone; enzalutamide; and radium-223 dichloride for the subgroup of people with bone metastasis only (no visceral metastasis). The company did not consider radium-223 dichloride to be a relevant comparator. Neither abiraterone nor enzalutamide has been directly compared in a trial with cabazitaxel. Instead, clinical evidence was synthesised within a network meta-analysis (NMA). Results from TROPIC showed that cabazitaxel was associated with a statistically significant improvement in both overall survival and progression-free survival compared with mitoxantrone. Results from a random-effects NMA, as conducted by the company and updated by the ERG, indicated that there was no statistically significant difference between the three active treatments for both overall survival and progression-free survival. Utility data were not collected as part of the TROPIC trial, and were instead taken from the company's UK early access programme. Evidence on resource use came from the TROPIC trial, supplemented by both expert clinical opinion and a UK clinical audit. List prices were used for mitoxantrone, abiraterone and enzalutamide as directed by NICE, although commercial in-confidence patient-access schemes (PASs) are in place for abiraterone and enzalutamide. The confidential PAS was used for cabazitaxel. Sequential use of the advanced hormonal therapies (abiraterone and enzalutamide) does not usually occur in clinical practice in the UK. Hence, cabazitaxel could be used within two pathways of care: either when an advanced hormonal therapy was used pre-docetaxel, or when one was used post-docetaxel. The company believed that the former pathway was more likely to represent standard National Health Service (NHS) practice, and so their main comparison was between cabazitaxel and mitoxantrone, with effectiveness data from the TROPIC trial. Results of the company's updated cost-effectiveness analysis estimated a probabilistic incremental cost-effectiveness ratio (ICER) of £45,982 per quality-adjusted life-year (QALY) gained, which the committee considered to be the most plausible value for this comparison. Cabazitaxel was estimated to be both cheaper and more effective than abiraterone. Cabazitaxel was estimated to be cheaper but less effective than enzalutamide, resulting in an ICER of £212,038 per QALY gained for enzalutamide compared with cabazitaxel. The ERG noted that radium-223 is a valid comparator (for the indicated sub-group), and that it may be used in either of the two care pathways. Hence, its exclusion leads to uncertainty in the cost-effectiveness results. In addition, the company assumed that there would be no drug wastage when cabazitaxel was used, with cost-effectiveness results being sensitive to this assumption: modelling drug wastage increased the ICER comparing cabazitaxel with mitoxantrone to over £55,000 per QALY gained. The ERG updated the company's NMA and used a random effects model to perform a fully incremental analysis between cabazitaxel, abiraterone, enzalutamide and best supportive care using PASs for abiraterone and enzalutamide. Results showed that both cabazitaxel and abiraterone were extendedly dominated by the combination of best supportive care and enzalutamide. Preliminary guidance from the committee, which included wastage of cabazitaxel, did not recommend its use. In response, the company provided both a further discount to the confidential PAS for cabazitaxel and confirmation from NHS England that it is appropriate to supply and purchase cabazitaxel in pre-prepared intravenous-infusion bags, which would remove the cost of drug wastage. As a result, the committee recommended use of cabazitaxel as a treatment option in people with an Eastern Cooperative Oncology Group performance status of 0 or 1 whose disease had progressed during or after treatment with at least 225 mg/m² of docetaxel, as long as it was provided at the discount agreed in the PAS and purchased in either pre-prepared intravenous-infusion bags or in vials at a reduced price to reflect the average per-patient drug wastage.

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.

Role of Chemotherapy and Mechanisms of Resistance to Chemotherapy in Metastatic Castration-Resistant Prostate Cancer

Chemotherapy using the taxanes, docetaxel and cabazitaxel, remains an important therapeutic option in metastatic castration-resistant prostate cancer (CRPC). However, despite the survival benefits afforded by these agents, the survival increments are modest and resistance occurs universally. Efforts to overcome resistance to docetaxel by combining with biologic agents have heretofore been unsuccessful. Indeed, resistance to these taxanes is also associated with cross-resistance to the antiandrogen drugs, abiraterone and enzalutamide. Here, we discuss the various mechanisms of resistance to chemotherapy in metastatic CRPC and the potential role of emerging regimens and agents in varying clinical phases of development.

Therapeutic management of bone metastasis in prostate cancer: an update

INTRODUCTION

Bone metastases affect the majority of patients with castration-resistant prostate cancer (CRPC), resulting in significant morbidity and mortality. This review describes the current therapies available for the management of CRPC patients with bone metastases. Areas covered: Studies on the use of currently available therapeutic approaches for palliating pain, delaying skeletal-related events (SREs) and prolonging survival in CRPC patients with bone metastases have been examined. PubMed database was searched in May 2016 starting with the following keywords: ('castration-resistant prostate cancer' OR 'CRPC') AND 'bone metastases', and approximately 270 results were retrieved. More specific searches were then performed on the epidemiology and molecular pathogenesis (in particular, 'vicious cycle' was used as a keyword), the management of pain, SREs and survival. The following keywords were also used individually: abiraterone, cabazitaxel, denosumab, docetaxel, enzalutamide, radium-223, sipuleucel-T, samarium-153, strontium-89, zoledronate. Randomized-controlled trials, observational studies, reviews, systematic reviews and meta-analyses were selected and articles were excluded if not in English. Expert commentary: Currently, clear recommendations on the optimal use of the agents available to treat mCRPC are lacking. Therefore, to ensure patients the best treatment, both their clinical characteristics and the features of each product have to be considered.

Effects of Budesonide on Cabazitaxel Pharmacokinetics and Cabazitaxel-Induced Diarrhea: A Randomized, Open-Label Multicenter Phase II Study

Purpose: Forty-seven percent of patients in the pivotal trial of cabazitaxel reported diarrhea of any grade. Aiming to reduce the incidence of diarrhea, we studied the effects of budesonide on the grade of cabazitaxel-induced diarrhea during the first two treatment cycles.Experimental Design: Between December 2011 and October 2015, 246 metastatic castration-resistant prostate cancer patients were randomized to receive standard-of-care cabazitaxel 25 mg/m² every 3 weeks plus prednisone 10 mg/day (group CABA) or same dose/schedule of cabazitaxel with concomitant budesonide 9 mg daily during the first two treatment cycles (group BUD). The occurrence of diarrhea was reported by physicians and by patients in a diary. χ² tests were used to compare incidence numbers. An intention-to-treat principle was used.Results: In the phase II trial, 227 patients were evaluable. Grade 2-3 diarrhea occurred in 35 patients (15%) and grade 4 diarrhea was not reported. The incidence of grade 2-3 diarrhea was comparable in both treatment groups: 14 of 113 patients in group CABA (12%) versus 21 of 114 patients in group BUD (18%; P = 0.21). Seven patients were admitted to the hospital with diarrhea (n = 5 group CABA vs. n = 2 group BUD). PSA response was seen in 30% of patients and was not affected by budesonide coadministration (P = 0.29). Also, other toxicities were not affected by budesonide coadministration.Conclusions: The incidence of cabazitaxel-induced diarrhea was notably lower than reported in the TROPIC trial and appears manageable in routine clinical practice. Budesonide coadministration did not reduce the incidence or severity of cabazitaxel-induced diarrhea. Clin Cancer Res; 23(7); 1679-83. ©2016 AACR.

Patient-reported outcomes in metastatic castration-resistant prostate cancer

Many novel therapies are available for use in patients with metastatic castration-resistant prostate cancer (mCRPC), some of which convey substantial progression-free survival and overall survival benefits. Delaying disease progression and providing palliation of symptoms are primary therapeutic aims of treating patients with mCRPC; therefore, ensuring that the benefit-to-harm ratios are acceptable to patients, through systematic measurement of patient-reported outcomes (PROs) using validated tools, is vital. In this Perspectives, we appraised the published reports from clinical trials testing treatments of mCRPC over the past 5 years and found that PROs were either not being measured routinely, or if used, were often not reported adequately, thus hampering evaluation of the true effects of many of these treatments on patients' quality of life. Improvements are needed because data collected directly from patients, not just physician-collected safety data and adverse events, are crucial to inform clinical decision-making on treatment options.

Efficacy, quality of life, and safety of cabazitaxel in Canadian metastatic castration-resistant prostate cancer patients treated or not with prior abiraterone

INTRODUCTION

In the TROPIC study, cabazitaxel improved overall survival in abiraterone-naïve metastatic castration-resistant prostate cancer (mCRPC) patients post-docetaxel. To evaluate cabazitaxel in routine clinical practice, an international, single-arm trial was conducted. Efficacy, safety, and quality of life (QoL) data were collected from Canadian patients enrolled. Overall survival and progression-free survival were not collected as part of this study. Importantly, prior abiraterone use was obtained and its impact on clinical parameters was examined.

METHODS

Sixty-one patients from nine Canadian centres were enrolled, with prior abiraterone use known for 60 patients. Prostate-specific antigen (PSA) response rate, safety, and impact on QoL life were analyzed as a function of prior abiraterone use.

RESULTS

Overall, 92% of patients were ECOG 0/1, 88% had bone metastases, and 25% visceral metastases. Patients treated without prior abiraterone (NoPriorAbi) (n=35, 58%) and with prior abiraterone (PriorAbi) (n=25, 42%) had similar baseline characteristics, except for age and prior cumulative docetaxel dose. Median number of cabazitaxel cycles received was similar between groups (NoPriorAbi=6, PriorAbi=7), as was PSA response rate (NoPriorAbi=36.4%, PriorAbi=45.0%, p=0.54). Almost one-third (31%) of patients received prophylactic granulocyte colony-stimulating factors. Most frequent Grade 3/4 toxicities were neutropenia (14.8%); anemia, febrile neutropenia, fatigue (each at 9.8%); and diarrhea (8.2%). No treatment-related adverse event leading to death was observed. QoL and pain were improved with no difference seen between groups. Treatment discontinuation was mainly due to disease progression (45.9%) and adverse events (32.8%).

CONCLUSIONS

In routine clinical practice, cabazitaxel's risk-benefit ratio in mCRPC patients previously treated with docetaxel seems to be maintained independent of prior abiraterone use.

Skeletal metastases and impact of anticancer and bone-targeted agents in patients with castration-resistant prostate cancer

Incidence of bone metastases is very high in advanced prostate cancer patients. Bone metastases likely have a significant impact on functional status and quality of life, not only related to pain, but also to the relevant risk of skeletal-related events. A better understanding of mechanisms associated with bone metastatic disease secondary to prostate cancer and more specifically to the cross-talk between tumor cells and bone microenvironment in metastatic progression represented the background for the development of new effective bone-targeted therapies. Furthermore, a better knowledge of biological mechanisms driving disease progression led to significant advances in the treatment of castration-resistant prostate cancer, with the development and approval of new effective drugs. Aim of this review is to outline the physiopathology of bone metastases in prostate cancer and summarize the main results of clinical trials conducted with different drugs to control morbidity induced by skeletal metastases and bone disease progression. For each agent, therapeutic effect on bone metastases has been measured in terms of pain control and/or incidence of skeletal-related events, usually defined as a composite endpoint, including the need for local treatment (radiation therapy or surgery), spinal cord compression, pathological bone fractures. In details, data obtained with chemotherapy (mitoxantrone, docetaxel, cabazitaxel), new generation hormonal agents (abiraterone, enzalutamide), radium-223, bone-targeted agents (zoledronic acid, denosumab) and with several experimental agents (cabozantinib, dasatinib, anti-endothelin and other agents) in patients with castration-resistant prostate cancer are reviewed.

Translating Clinical Evidence-Based Medicine into the Real World: Single-Center Experience with Cabazitaxel in Metastatic Prostate Cancer Patients

Background: We studied the efficacy and safety of cabazitaxel in unselected real-life patients. Patients and Methods: We retrospectively investigated all patients with metastatic prostate cancer (mPC) treated with cabazitaxel 25 mg/m2 i.v. every 3 weeks combined with oral prednisolone (10 mg once daily) after first-line docetaxel chemotherapy. Study issues were to report patient characteristics and cabazitaxel data in terms of tolerance and efficacy. Overall survival (OS) and progression-free survival (PFS) were evaluated using the Kaplan-Meier method. All data were compared with TROPIC results. Results: From 2011 to 2014, 41 patients received cabazitaxel; 15 patients (37%) had a performance status (PS) ≥2 versus 7% (p < 0.0001) in TROPIC, and 38 patients (93%) presented a Gleason score ≥7 at baseline (vs. 60%; p < 0.0001). All patients had metastatic disease at baseline. Previous therapies were radiotherapy in 17 patients (41 vs. 61%; p = 0.01) and surgery in 24 patients (59 vs. 52%; p = 0.4). The median number of cabazitaxel cycles was 5 (1-10) versus 6 (3-10) in TROPIC. Five patients completed 10 cycles of cabazitaxel (12%) versus 28% in TROPIC (p = 0.03). Toxicities were anemia (12 patients, 29%), diarrhea (9 patients, 22%), nausea (7 patients, 17%), pain (6 patients, 15%), sepsis (4 patients, 10%), neutropenia (3 patients, 7%) and urinary tract infection (1 patient, 2%). The tumor response rate was 19.5 versus 14.4% in TROPIC (nonsignificant). PFS was 4.5 months (95% CI 3.3-6.4) in our analysis and 2.8 months (95% CI 2.4-3.0) in TROPIC. OS was 12.1 months (95% CI 9.2 to not reached) and 15.1 months (95% CI 14.1-16.3), respectively. Conclusion: In our unselected mPC patients with poorer baseline clinical conditions and aggressive disease, cabazitaxel seems efficient and not more toxic than in the TROPIC study.