Additional Analysis of the Secondary End Point of Biochemical Recurrence Rate in a Phase 3 Trial (CS21) Comparing Degarelix 80mg Versus Leuprolide in Prostate Cancer Patients Segmented by Baseline Characteristics

Gonadotropin-releasing hormone antagonists versus standard androgen suppression therapy for advanced prostate cancer A systematic review with meta-analysis

OBJECTIVES

To evaluate efficacy and safety of gonadotropin-releasing hormone (GnRH) antagonists compared to standard androgen suppression therapy for advanced prostate cancer.

SETTING

The international review team included methodologists of the German Cochrane Centre and clinical experts.

PARTICIPANTS

We searched CENTRAL, MEDLINE, Web of Science, EMBASE, trial registries and conference books for randomised controlled trials (RCT) for effectiveness data analysis, and randomised or non-randomised controlled studies (non-RCT) for safety data analysis (March 2015). Two authors independently screened identified articles, extracted data, evaluated risk of bias and rated quality of evidence according to GRADE.

RESULTS

13 studies (10 RCTs, 3 non-RCTs) were included. No study reported cancer-specific survival or clinical progression. There were no differences in overall mortality (RR 1.35, 95% CI 0.63 to 2.93), treatment failure (RR 0.91, 95% CI 0.70 to 1.17) or prostate-specific antigen progression (RR 0.83, 95% CI 0.64 to 1.06). While there was no difference in quality of life related to urinary symptoms, improved quality of life regarding prostate symptoms, measured with the International Prostate Symptom Score (IPSS), with the use of GnRH antagonists compared with the use of standard androgen suppression therapy (mean score difference -0.40, 95% CI -0.94 to 0.14, and -1.84, 95% CI -3.00 to -0.69, respectively) was found. Quality of evidence for all assessed outcomes was rated low according to GRADE. The risk for injection-site events was increased, but cardiovascular events may occur less often by using GnRH antagonist. Available evidence is hampered by risk of bias, selective reporting and limited follow-up.

CONCLUSIONS

There is currently insufficient evidence to make firm conclusive statements on the efficacy of GnRH antagonist compared to standard androgen suppression therapy for advanced prostate cancer. There is need for further high-quality research on GnRH antagonists with long-term follow-up.

TRIAL REGISTRATION NUMBER

CRD42012002751.

Pharmacokinetic and pharmacodynamic profile of degarelix for prostate cancer

INTRODUCTION

Luteinizing hormone-releasing hormone (LHRH) agonists have been the mainstay of androgen deprivation therapy (ADT) for advanced prostate cancer for over two decades. However, their limitations include a transient initial rise in testosterone, failure to reduce testosterone to castrate levels in some patients, incomplete suppression of follicle-stimulating hormone (FSH), and an increased risk of cardiovascular (CV) events in those with pre-existing CV disease. This article considers whether the LHRH antagonist degarelix offers significant advantages over LHRH agonists.

AREAS COVERED

This review covers the development and introduction of degarelix, its pharmacodynamic and pharmacokinetic properties, and the efficacy and safety results of Phase II and III clinical studies.

EXPERT OPINION

Degarelix has clear pharmacodynamic advantages over the LHRH agonist leuprolide in terms of almost immediate suppression of testosterone to castrate levels and sustained suppression of FSH levels. It reduces the risk of CV events vs agonists in men with pre-existing CV disease. This finding, which may reflect differential effects on FSH and/or endothelial plaques, requires confirmation in a prospective study; however, it is the view of the author that the differential effects on CV events are real and suggest that men with pre-existing CV disease requiring ADT should preferentially be treated with degarelix.

Efficacy of degarelix in prostate cancer patients following failure on luteinizing hormone-releasing hormone agonist treatment: results from an open-label, multicentre, uncontrolled, phase II trial (CS27)

OBJECTIVE

To evaluate the efficacy of second-line degarelix in patients with prostate cancer (PCa) after treatment failure with a luteinizing hormone-releasing hormone (LHRH) agonist.

METHODS

This 1-year exploratory, multicentre, open-label phase II trial was performed in 2 patient cohorts (Cohort 1, n = 25; Cohort 2, n = 12) in Germany. Patients with castrate-resistant PCa after primary hormonal treatment received degarelix 240 mg, followed by 11 monthly maintenance doses of 80 mg. The primary endpoint was the proportion of patients with decreasing/stable prostate-specific antigen (PSA) (relative change ⩽+10% of baseline PSA) after 3 months.

RESULTS

At Month 3, the response rate (intention-to-treat, last observation carried forward analysis) was 16.7% [95% confidence interval (CI): 4.74-37.38] in Cohort 1 and 33.3% (95% CI: 9.92-65.11) in Cohort 2. The probability of completing 12 months without PSA progression was 8.8% (95% CI: 1.51-24.3) in Cohort 1 and 8.3% (95% CI: 0.5-31.1) in Cohort 2. Degarelix was well tolerated; the most frequently reported adverse events were local injection-site reactions.

CONCLUSIONS

In PCa patients who failed LHRH therapy, degarelix was well tolerated and achieved a limited PSA response. Phase III trials show that disease control benefits with degarelix versus agonists are more clearly demonstrated as first-line therapy.

Degarelix: a review of its use in patients with prostate cancer

Degarelix (Firmagon(®); Gonax(®)) is a gonadotropin-releasing hormone receptor antagonist that is approved for the treatment of advanced (hormone-dependent) prostate cancer in the US and EU and the treatment of prostate cancer in Japan. In a pivotal randomized, controlled, 12-month phase III study, degarelix (initial subcutaneous dose of 240 mg followed by monthly dosages of 80 mg) was noninferior to leuprolide (monthly intramuscular dosages of 7.5 mg) in patients with prostate cancer of any stage for which endocrine treatment was indicated (except neoadjuvant hormonal therapy) with regard to suppression of testosterone to castration levels (i.e. ≤0.5 ng/mL). Suppression of testosterone and prostate-specific antigen (PSA) levels was faster with degarelix than with leuprolide, and no testosterone surges or microsurges were seen in degarelix recipients. Suppression of testosterone and PSA levels was maintained for the 12-month study duration and continued for up to 5 years in an extension to the main trial (including in patients switching from leuprolide to degarelix in the extension). The drug was generally well tolerated, with most adverse events being mild to moderate in severity. Injection-site reactions and events reflecting the expected effects of testosterone suppression (e.g. hot flushes, weight increase) were the most common treatment-emergent adverse events. Thus, degarelix is a useful option for the treatment of prostate cancer in patients for whom endocrine treatment is indicated.

Disease control outcomes from analysis of pooled individual patient data from five comparative randomised clinical trials of degarelix versus luteinising hormone-releasing hormone agonists

BACKGROUND

Studies comparing the gonadotropin-releasing hormone antagonist, degarelix, with luteinising hormone-releasing hormone (LHRH) agonists indicate differences in outcomes.

OBJECTIVE

To assess differences in efficacy and safety outcomes in a pooled analysis of trials comparing degarelix with LHRH agonists.

DESIGN, SETTING, AND PARTICIPANTS

Data were pooled from five prospective, phase 3 or 3b randomised trials (n=1925) of degarelix and leuprolide or goserelin in men requiring androgen deprivation therapy for the treatment of prostate cancer. Patients received either 3 mo (n=467) or 12 mo (n=1458) of treatment.

INTERVENTION

Men were randomised to receive degarelix (n=1266), leuprolide (n=201), or goserelin (n=458).

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Unadjusted Kaplan-Meier analyses were supported by the Cox proportional hazards model, adjusted for disease-related baseline factors, to estimate hazard ratios (HRs) of efficacy and safety outcomes. The Fisher exact test compared crude incidences of adverse events.

RESULTS AND LIMITATIONS

Prostate-specific antigen (PSA) progression-free survival (PFS) was improved in the degarelix group (HR: 0.71; p=0.017). For patients with baseline PSA levels >20 ng/ml, the HR for PSA PFS was 0.74 (p=0.052). Overall survival (OS) was higher in the degarelix group (HR: 0.47; p=0.023). OS was particularly improved with degarelix in patients with baseline testosterone levels >2 ng/ml (HR: 0.36; p=0.006). In terms of disease-related adverse events, there were, overall, fewer joint-related signs and symptoms, musculoskeletal events, and urinary tract events in the degarelix group.

CONCLUSIONS

These data indicate clinical benefits with degarelix, including a significant improvement in PSA PFS and OS, as well as reduced incidence of joint, musculoskeletal, and urinary tract adverse events, compared with LHRH agonists.

Quality of life improvement in patients treated with degarelix versus leuprorelin for advanced prostate cancer

PURPOSE

We used responses to questionnaires included in the CS21 degarelix trial and published mapping algorithms to address the paucity of evidence for health related quality of life in patients with advanced hormone dependent prostate cancer treated with degarelix.

MATERIALS AND METHODS

We measured health related quality of life in 610 patients enrolled in the CS21 trial using SF-12® and EORTC QLQ-C30. Based on responses to these questionnaires we estimated patient utility using 4 published mapping algorithms. Utility was tested for relationships with aspects of the symptom and side effect burden that may be affected by degarelix treatment, that is prostate specific antigen progression and adverse events.

RESULTS

Average utility in patients without prostate specific antigen progression or an adverse event was 0.742, similar to previously published utilities for nonprogressed prostate cancer states. Prostate specific antigen progression was associated with a utility decrement of between 0.062 and 0.134 depending on the mapping algorithm used. Of adverse events considered in our analysis musculoskeletal events were associated with the greatest effects on patient utility with a decrement of between 0.029 and 0.086. The 4 mapping algorithms generated similar utility estimates, although values derived from SF-12 were consistently lower than those derived from EORTC QLQ-C30.

CONCLUSIONS

Prostate specific antigen progression status and the incidence of treatment and disease related adverse events result in significant decrements to patient health related quality of life. By slowing prostate specific antigen progression degarelix may improve patient utility and the health related quality of life burden.

Androgen receptor as a driver of therapeutic resistance in advanced prostate cancer

The role of the androgen receptor (AR) signaling axis in the progression of prostate cancer is a cornerstone to our understanding of the molecular mechanisms causing castration-resistant prostate cancer (CRPC). Resistance of advanced prostate cancer to available treatment options makes it a clinical challenge that results in approximately 30,000 deaths of American men every year. Since the historic discovery by Dr. Huggins more than 70 years ago, androgen deprivation therapy (ADT) has been the principal treatment for advanced prostate cancer. Initially, ADT induces apoptosis of androgen-dependent prostate cancer epithelial cells and regression of androgen-dependent tumors. However, the majority of patients with advanced prostate cancer progress and become refractory to ADT due to emergence of androgen-independent prostate cancer cells driven by aberrant AR activation. Microtubule-targeting agents such as taxanes, docetaxel and paclitaxel, have enjoyed success in the treatment of metastatic prostate cancer; although new, recently designed mitosis-specific agents, such as the polo-kinase and kinesin-inhibitors, have yielded clinically disappointing results. Docetaxel, as a first-line chemotherapy, improves prostate cancer patient survival by months, but tumor resistance to these therapeutic agents inevitably develops. On a molecular level, progression to CRPC is characterized by aberrant AR expression, de novo intraprostatic androgen production, and cross talk with other oncogenic pathways. Emerging evidence suggests that reactivation of epithelial-mesenchymal-transition (EMT) processes may facilitate the development of not only prostate cancer but also prostate cancer metastases. EMT is characterized by gain of mesenchymal characteristics and invasiveness accompanied by loss of cell polarity, with an increasing number of studies focusing on the direct involvement of androgen-AR signaling axis in EMT, tumor progression, and therapeutic resistance. In this article, we discuss the current knowledge of mechanisms via which the AR signaling drives therapeutic resistance in prostate cancer metastatic progression and the novel therapeutic interventions targeting AR in CRPC.

A cost-utility analysis of degarelix in the treatment of advanced hormone-dependent prostate cancer in the United Kingdom

OBJECTIVE

To determine the cost-effectiveness of the treatment of advanced hormone-dependent prostate cancer with degarelix compared to luteinizing hormone-releasing hormone (LHRH) agonists in the UK using the latest available evidence and the model submitted to AWMSG.

METHODS

A cost-effectiveness model was developed from the perspective of the UK National Health Service evaluating monthly injection of degarelix against 3-monthly leuprorelin therapy plus anti-androgen flare cover for the first-line treatment of patients with advanced (locally advanced or metastatic) hormone-dependent prostate cancer. A Markov process model was constructed using the patient population characteristics and efficacy information from the CS21 Phase III clinical trial and associated extension study (CS21A). The intention-to-treat (ITT) population and a high-risk sub-group with a PSA level >20 ng/mL were modeled.

RESULTS

In the base-case analysis using the patient access scheme (PAS) price, degarelix was dominant compared to leuprorelin with cost savings of £3633 in the ITT population and £4310 in the PSA > 20 ng/mL sub-group. The chance of being cost-effective was 95% in the ITT population and 96% in the PSA > 20 ng/mL sub-group at a threshold of £20,000 per quality-adjusted life-year (QALY). In addition, degarelix remained dominant when PSA progression was assumed equal and only the benefits of preventing testosterone flare were taken into account. Treatment with degarelix also remained dominant in both populations when the list price was used. The additional investment required to treat patients with degarelix could be offset in 19 months for the ITT population and 13 months for the PSA > 20 ng/mL population. The model was most sensitive to the hazard ratio assumed for PSA progression between degarelix and leuprorelin and the quality-of-life (utility) of patients receiving palliative care.

CONCLUSION

Degarelix is likely to be cost-effective compared to leuprorelin plus anti-androgen flare cover in the first-line treatment of advanced hormone-dependent prostate cancer.

Long-term tolerability and efficacy of degarelix: 5-year results from a phase III extension trial with a 1-arm crossover from leuprolide to degarelix

OBJECTIVE

To demonstrate the safety and efficacy of up to 5 years of degarelix treatment and the effects of crossing over from leuprolide to degarelix in the extension phase of a phase III pivotal 1-year trial.

METHODS

Patients receiving degarelix who completed the 1-year trial continued on 80 mg (n = 125) or 160 mg (n = 126) maintenance doses. Patients who received leuprolide were rerandomized to degarelix 240/80 mg (n = 69) or 240/160 mg (n = 65). Safety and tolerability were assessed (primary end point), as well as testosterone and prostate-specific antigen levels and prostate-specific antigen progression-free survival (secondary end points).

RESULTS

Adverse event frequency was similar between both the groups. Adverse events included initial injection site reactions, hot flushes, and increased weight. Testosterone and prostate-specific antigen values during the extension study were similar to those seen during the 1-year trial in patients who continued on degarelix or crossed over from leuprolide. The prostate-specific antigen progression-free survival hazard rate was decreased significantly after the crossover in the leuprolide to degarelix group (from 0.20 to 0.09; P = .002), whereas in patients who continued on degarelix, the rate did not change significantly. In patients with baseline prostate-specific antigen >20 ng/mL, the same hazard rate change pattern was observed on crossover (from 0.38 to 0.19; P = .019).

CONCLUSION

Degarelix was well tolerated; no safety concerns were identified. The significant prostate-specific antigen progression-free survival benefit established for degarelix over leuprolide during year 1 remained consistent at 5 years.

Current trends for the use of androgen deprivation therapy in conjunction with radiotherapy for patients with unfavorable intermediate-risk, high-risk, localized, and locally advanced prostate cancer

Androgen deprivation therapy (ADT) is now a well-established standard of care in combination with definitive radiotherapy for patients with unfavorable intermediate-risk to high-risk locally advanced prostate cancer. It is also well established that combination modality treatment with ADT and radiotherapy is superior to either of these modalities alone for the treatment of patients with high-risk locally advanced disease. Current treatment guidelines for prostate cancer in the United States are based on the estimated risk of recurrence and death. This review examines the clinical evidence underpinning the use of ADT and radiotherapy among patients with high-risk localized and locally advanced disease in the United States. This review also considers the rationale for moving from traditional luteinizing hormone-releasing hormone agonists to more recently developed gonadotrophin-releasing hormone antagonists.

An unusual prostate-specific antigen decrease in an advanced castration-resistant prostate cancer patient with intracerebral hemorrhage subsequently treated with luteinizing hormone-releasing hormone antagonist

An unusual prostate-specific antigen (PSA) decrease in a Japanese patient with advanced castration-resistant prostate cancer (CRPC) treated with luteinizing hormone-releasing hormone (LH-RH) antagonist after cerebral bleeding was presented. There have been no previous reports that cerebral bleeding or trepanation/drainage of hematoma decreased PSA level, which would make this the first. The LH-RH antagonist may be only one reason for the PSA decrease. More cases need to be accumulated and and further investigation is needed to clarify if intracerebral bleeding or an LH-RH antagonist can decrease PSA in such advanced CRPC cases.

EAU guidelines on prostate cancer. Part II: Treatment of advanced, relapsing, and castration-resistant prostate cancer

OBJECTIVE

To present a summary of the 2013 version of the European Association of Urology (EAU) guidelines on the treatment of advanced, relapsing, and castration-resistant prostate cancer (CRPC).

EVIDENCE ACQUISITION

The working panel performed a literature review of the new data (2011-2013). The guidelines were updated, and levels of evidence and/or grades of recommendation were added to the text based on a systematic review of the literature that included a search of online databases and bibliographic reviews.

EVIDENCE SYNTHESIS

Luteinising hormone-releasing hormone (LHRH) agonists are the standard of care in metastatic prostate cancer (PCa). LHRH antagonists decrease testosterone without any testosterone surge, and they may be associated with an oncologic benefit compared with LHRH analogues. Complete androgen blockade has a small survival benefit of about 5%. Intermittent androgen deprivation results in noninferior oncologic efficacy when compared with continuous androgen-deprivation therapy (ADT) in well-selected populations. In locally advanced and metastatic PCa, early ADT does not result in a significant survival advantage when compared with delayed ADT. Relapse after local therapy is defined by prostate-specific antigen (PSA) values >0.2 ng/ml following radical prostatectomy (RP) and >2 ng/ml above the nadir and after radiation therapy (RT). Therapy for PSA relapse after RP includes salvage RT (SRT) at PSA levels <0.5 ng/ml and SRP or cryosurgical ablation of the prostate in radiation failures. Endorectal magnetic resonance imaging and 11C-choline positron emission tomography/computed tomography (PET/CT) are of limited importance if the PSA is <1.0 ng/ml; bone scans and CT can be omitted unless PSA is >20 ng/ml. Follow-up after ADT should include analysis of PSA and testosterone levels, and screening for cardiovascular disease and metabolic syndrome. Treatment of CRPC includes sipuleucel-T, abiraterone acetate plus prednisone (AA/P), or chemotherapy with docetaxel at 75mg/m(2) every 3 wk. Cabazitaxel, AA/P, enzalutamide, and radium-223 are available for second-line treatment of CRPC following docetaxel. Zoledronic acid and denosumab can be used in men with CRPC and osseous metastases to prevent skeletal-related complications.

CONCLUSIONS

The knowledge in the field of advanced, metastatic, and castration-resistant PCa is rapidly changing. These EAU guidelines on PCa summarise the most recent findings and put them into clinical practice. A full version is available at the EAU office or at www.uroweb.org.

PATIENT SUMMARY

We present a summary of the 2013 version of the European Association of Urology guidelines on treatment of advanced, relapsing, and castration-resistant prostate cancer (CRPC). Luteinising hormone-releasing hormone (LHRH) agonists are the standard of care in metastatic prostate cancer (PCa). LHRH antagonists decrease testosterone without any testosterone surge, and they might be associated with an oncologic benefit compared with LHRH analogues. Complete androgen blockade has a small survival benefit of about 5%. Intermittent androgen deprivation results in noninferior oncologic efficacy when compared with continuous androgen-deprivation therapy (ADT) in well-selected populations. In locally advanced and metastatic PCa, early ADT does not result in a significant survival advantage when compared with delayed ADT. Relapse after local therapy is defined by prostate-specific antigen (PSA) values >0.2 ng/ml following radical prostatectomy (RP) and >2 ng/ml above the nadir and after radiation therapy. Therapy for PSA relapse after RP includes salvage radiation therapy at PSA levels <0.5 ng/ml and salvage RP or cryosurgical ablation of the prostate in radiation failures. Multiparametric magnetic resonance imaging and 11C-choline positron emission tomography/computed tomography (PET/CT) are of limited importance if the PSA is <1.0 ng/ml; bone scans, and CT can be omitted unless PSA is >20 ng/ml. Follow-up after ADT should include analysis of PSA and testosterone levels, and screening for cardiovascular disease and metabolic syndrome. Treatment of castration-resistant CRPC includes sipuleucel-T, abiraterone acetate plus prednisone (AA/P), or chemotherapy with docetaxel 75 mg/m(2) every 3 wk. Cabazitaxel, AA/P, enzalutamide, and radium-223 are available for second-line treatment of CRPC following docetaxel. Zoledronic acid and denosumab can be used in men with CRPC and osseous metastases to prevent skeletal-related complications. The guidelines reported should be adhered to in daily routine to improve the quality of care in PCa patients. As we have shown recently, guideline compliance is only in the area of 30-40%.

Cost-effectiveness analysis comparing degarelix with leuprolide in hormonal therapy for patients with locally advanced prostate cancer

Degarelix, approved in the USA in 2008, is a gonadotropin-releasing hormone antagonist, representing one of the latest additions to androgen deprivation therapy (ADT). ADT is used as first-line therapy for locally advanced or metastatic prostate cancer with the aim to reduce testosterone to castrate levels. Like other gonadotropin-releasing hormone-antagonists, degarelix treatment results in rapid decrease in luteinizing hormone, follicle-stimulating hormone and testosterone levels without the associated risk of flare. Using one registration trial for degarelix with leuprolide as the active control, a cost-effectiveness analysis with a Markov model and a 20-year time horizon found the incremental cost-effectiveness ratio for degarelix to be US$245/quality-adjusted life years. Degarelix provides a cost-effective treatment for ADT among patients with locally advanced prostate cancer.

[Hormonal treatment in prostate cancer]

AIM

To describe drugs used in the hormonal treatment (hormonotherapy) of prostate cancer.

MATERIAL

Bibliographical search was performed from the database Medline (National Library of Medicine, PubMed) and websites of the HAS and the ANSM. The search was focused on the characteristics, the mode of action, the efficiency and the side effects of the various drugs concerned.

RESULTS

LHRH analogs and the antiandrogens remain the cornerstone in the treatment of locally advanced and metastatic prostate cancer. New therapeutic classes emerged recently (inhibitor of the synthesis of the androgen, the new antiandrogens) and allowed to grow again the limits of the hormone resistance and define the concept castration-resistant prostate cancer.

CONCLUSION

The hormonal treatment of the prostate cancer grew rich of new therapeutic classes which are going to change the medical care of the prostate cancer in the coming years and the urologist must play its full part.

The hypothalamic-pituitary-gonadal axis and prostate cancer: implications for androgen deprivation therapy

Luteinizing hormone (LH) and follicle-stimulating hormone (FSH) may play important roles in prostate cancer (PCa) progression. Specifically, LH expression in PCa tissues has been associated with metastatic disease with a poor prognosis, while FSH has been shown to stimulate prostate cell growth in hormone-refractory PCa cell lines. Gonadotropin-realizing hormone (GnRH) analogues are common agents used for achieving androgen deprivation in the treatment for PCa. GnRH analogues include LH-releasing hormone (LHRH) agonists and GnRH antagonists, both of which exhibit distinct mechanisms of action that may be crucial in terms of their overall clinical efficacy. LHRH agonists are typically used as the primary therapy for most patients and function via a negative-feedback mechanism. This mechanism involves an initial surge in testosterone levels, which may worsen clinical symptoms of PCa. GnRH antagonists provide rapid and consistent hormonal suppression without the initial surge in testosterone levels associated with LHRH agonists, thus representing an important therapeutic alternative for patients with PCa. The concentrations of testosterone and dihydrotestosterone are significantly reduced after treatment with both LHRH agonists and GnRH antagonists. This reduction in testosterone concentrations to castrate levels results in significant, rapid, and consistent reductions in prostatic-specific antigen, a key biomarker for PCa. Evidence suggests that careful maintenance of testosterone levels during androgen deprivation therapy provides a clinical benefit to patients with PCa, emphasizing the need for constant monitoring of testosterone concentrations throughout the course of therapy.

Luteinizing hormone-releasing hormone antagonists for urinary obstruction in prostate cancer

Luteinizing hormone-releasing hormone (LHRH) antagonists rapidly reduce testosterone and are preferred to LHRH agonists in situations when early response is important. The lack of flare reaction, as compared to LHRH agonists, is particularly desirable as it would not aggravate the problem. A 78-year-old man presented with symptoms of urinary tract obstruction. He had a prostate-specific antigen (PSA) of 91.3 ug/L and serum creatinine 146 umol/L. He had a large pelvic mass due to histologically confirmed prostate cancer, resulting in moderate left hydronephrosis and deteriorating renal function (serum creatinine of 163 umol/L). He was started on combined degarelix and bicalutamide on the day of consultation (day 0). The hydronephrosis resolved on the repeat computerized tomography scan performed on day 10. Serum creatinine normalized to under 130 umol/L on day 18. The PSA fell to 11 ug/L on day 18, 2.8 ug/L on day 28, and 0.5 ug/L on day 53. Therefore, LHRH antagonists are particularly useful in urgent situations. It is the preferred choice in these circumstances.

Non-castrate metastatic prostate cancer: have the treatment options changed?

Over the past 7 decades androgen-deprivation therapy (ADT) has been the cornerstone of treatment for metastatic non-castrate prostate cancer (NCPC); however, the mechanisms to achieve this goal have evolved over time to include not only bilateral orchiectomy and estrogens, but also gonadotropin-releasing hormone (GnRH) agonists, antagonists, and the inclusion of androgen receptor (AR) blockade. Despite treatment with ADT, most men will progress to castrate-resistant prostate cancer (CRPC). Over the last decade many new treatment options for CRPC have emerged. These new treatments also could have a meaningful role earlier in NCPC. In this review, we outline the biologic drivers of NCPC, review current standard therapy available for NCPC, and discuss the evolving role of new therapeutics in metastatic disease.

Agonists of luteinizing hormone-releasing hormone in prostate cancer

INTRODUCTION

Androgen deprivation therapy (ADT) has been the first-line standard of care for treating patients with hormone-sensitive advanced prostate cancer (PCa) for many decades. The agonists of luteinizing hormone-releasing hormone (LHRH), also called gonadotropin-releasing hormone, are still the most frequently used form of medical ADT.

AREAS COVERED

This article reviews the available data and most recent information concerning the use of LHRH agonists in advanced PCa. This article also reviews the discovery and development of LHRH agonists and summarizes the clinical evidence for their efficacy in PCa.

EXPERT OPINION

The introduction and application of agonists of LHRH has modernized and improved the treatment of advanced PCa. The life-saving benefits of LHRH agonists are well established, yet underestimated. Despite their efficacy, agonists of LHRH have several disadvantages or drawbacks including disease flare. The approach to ADT has been recently further refined with the development of the LHRH antagonist degarelix. Degarelix, a highly clinically effective third-generation LHRH antagonist, is currently available in most countries for therapy of advanced PCa. This new drug offers attractive alternatives to LHRH agonists for treatment of advanced PCa. A therapy for castration-resistant PCa based on a targeted cytotoxic analog of LHRH, AEZS-108, is also emerging.

Non-metastatic CRPC and asymptomatic metastatic CRPC: which treatment for which patient?

The introduction of early PSa-based diagnosis has profoundly impacted the epidemiology of castration-resistant prostate cancer (CRPC). Many patients enter the disease at an early stage when the only sign of resistance to androgen deprivation therapy (ADT) is a progressive elevation of prostate-specific antigen (PSA). This created a very heterogeneous population of non-metastatic (M0) CRPC. PSa kinetics is the most powerful indicator of aggressiveness in that population and can be used to trigger imaging investigation and enrollment in clinical trials. Several registered and near to come treatments have not been tested in that population but in men with more advanced metastatic and often symptomatic disease. Several agents have been investigated to delay the onset of the first bone metastasis but only one, denosumab, has reached its end-point. Because CRPC remains largely driven by the androgen receptor (AR), physicians have relied on second-line hormonal manipulations to delay the progression of the disease, including first generation antiandrogens, adrenal synthesis inhibitors, steroids and estrogens. The data however are mostly limited to phase II trials.

An update on the use of degarelix in the treatment of advanced hormone-dependent prostate cancer

Androgen deprivation therapy remains the mainstay of medical treatment for advanced prostate cancer. Commonly, this is achieved with medical androgen deprivation rather than surgical intervention as the permanence and psychological effects of the latter are unacceptable for most patients. Degarelix is a third generation antagonist of luteinizing hormone-releasing hormone (LHRH, also termed gonadotropin-releasing hormone) for the first-line treatment of androgen-dependent advanced prostate cancer. Degarelix acts directly on the pituitary receptors for LHRH, blocking the action of endogenous LHRH. The use of degarelix eliminates the initial undesirable surge in gonadotropin and testosterone levels, which is produced by agonists of LHRH. Degarelix is the most comprehensively studied and widely available LHRH antagonist worldwide. Clinical trials have demonstrated that degarelix has a long-term efficacy similar to the LHRH agonist leuprolide in achieving testosterone suppression in patients with prostate cancer. Degarelix, however, produces a faster suppression of testosterone and prostate-specific antigen (PSA), with no testosterone surges or microsurges, and thus prevents the risk of clinical flare in advanced disease. Recent clinical trials demonstrated that treatment with degarelix results in improved disease control when compared with an LHRH agonist in terms of superior PSA progression-free survival, suggesting that degarelix likely delays progression to castration-resistant disease and has a more significant impact on bone serum alkaline phosphatase and follicle-stimulating hormone. Degarelix is usually well tolerated, with limited toxicity and no evidence of systemic allergic reactions in clinical studies. Degarelix thus represents an important addition to the hormonal armamentarium for therapy of advanced androgen-dependent prostate cancer.

Experience with degarelix in the treatment of prostate cancer

Degarelix is a gonadotrophin-releasing hormone (GnRH) antagonist for the first-line treatment of androgen-dependent advanced prostate cancer. It has a direct mechanism of action that blocks the action of GnRH on the pituitary with no initial surge in gonadotrophin or testosterone levels. Degarelix is the most extensively studied and widely available GnRH antagonist worldwide. Clinical studies have demonstrated similar efficacy to the GnRH agonist leuprolide in achieving testosterone suppression in patients with prostate cancer. However, degarelix produces a faster suppression of testosterone and prostate-specific antigen (PSA), with no testosterone surge or microsurges, thus preventing the risk of clinical flare in advanced disease. Clinical trials have demonstrated that degarelix can offer improved disease control when compared with a GnRH agonist in terms of superior PSA progression-free survival (suggesting that degarelix likely delays progression to castration-resistant disease), and a more significant impact on bone serum alkaline phosphatase and follicle-stimulating hormone. Degarelix is generally well tolerated, with no reports of systemic allergic reactions in any clinical studies. In conclusion, degarelix offers clinicians a rational first-line hormonal monotherapy option for the management of advanced prostate cancer.

Degarelix versus goserelin (+ antiandrogen flare protection) in the relief of lower urinary tract symptoms secondary to prostate cancer: results from a phase IIIb study (NCT00831233)

INTRODUCTION

No studies to date have assessed the efficacy/tolerability of degarelix in the relief of lower urinary tract symptoms (LUTS) secondary to prostate cancer (PrCa).

METHODS

Patients were randomised to degarelix 240/80 mg or goserelin 3.6 mg + bicalutamide flare protection (G+B); both treatments were administered for 3 months. The primary endpoint was change in International Prostate Symptom Score (IPSS) at week 12 compared with baseline.

RESULTS

This study was stopped early due to recruitment difficulties. 40 patients received treatment (degarelix n = 27; G+B n = 13); most had locally advanced disease and were highly symptomatic. Degarelix was non-inferior to G+B in reducing IPSS at week 12 in the full analysis set (p = 0.20); the significantly larger IPSS reduction in the per-protocol analysis (p = 0.04) was suggestive of superior reductions with degarelix. Significantly more degarelix patients had improved quality of life (IPSS question) at week 12 (85 vs. 46%; p = 0.01). Mean prostate size reductions at week 12 were 42 versus 25% for patients receiving degarelix versus G+B, respectively (p = 0.04; post hoc analysis). Most adverse events were mild/moderate; more degarelix patients experienced injection site reactions whereas more G+B patients had urinary tract infections/cystitis.

CONCLUSION

In 40 men with predominantly locally advanced PrCa and highly symptomatic LUTS, degarelix was at least non-inferior to G+B in reducing IPSS at week 12.

Detectable prostate-specific antigen Nadir during androgen-deprivation therapy predicts adverse prostate cancer-specific outcomes: results from the SEARCH database

BACKGROUND

A prostate-specific antigen (PSA) level <0.2 ng/ml 8 mo after starting on androgen-deprivation therapy (ADT) is correlated with better outcomes. However, not all men reach a nadir PSA level within 8 mo. Whether the lowest PSA on ADT-specifically, <0.2 ng/ml-can be used for risk stratification is untested.

OBJECTIVE

We examined the predictive value of small but detectable PSA nadir values on prostate cancer (PCa)-specific outcomes in men treated with early ADT after radical prostatectomy (RP).

DESIGN, SETTING, AND PARTICIPANTS

We performed a retrospective review of men treated with ADT after RP before metastases from the SEARCH database. We identified 402 men treated with ADT for elevated PSA following RP, of whom 294 men had complete data. Median follow-up after PSA nadir was 49 mo. All men had a PSA nadir <4 ng/ml; 223 men (76%) had an undetectable nadir.

INTERVENTION

ADT for an elevated PSA following RP with no radiographic evidence of metastatic disease.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

PSA nadir on ADT was defined as the lowest PSA value during ADT. Proportional hazards models and the C index were used to test the association and predictive accuracy, respectively, between PSA nadir and PCa-specific outcomes.

RESULTS AND LIMITATIONS

Men with a PSA nadir between 0.01 and 0.2 ng/ml had a greater risk of progression to castration-resistant PCa (CRPC) (hazard ratio [HR]: 5.14; p<0.001), metastases (HR: 3.98; p=0.006), and PCa-specific mortality (PCSM) (HR: 5.33; p=0.003) than men with an undetectable nadir. When data were restricted to men followed with ultrasensitive PSA values (sensitivity of 0.01 ng/ml), the C index of PSA nadir alone for predicting CRPC, metastases, and PCSM was 0.88, 0.91, and 0.96, respectively.

CONCLUSIONS

A PSA nadir on ADT, even at a very low level, strongly predicts progression to CRPC, metastases, and PCSM. Men with a detectable PSA nadir during ADT should be considered for clinical trials.

Progress in emerging therapies for advanced prostate cancer

The landscape of prostate cancer treatment is rapidly changing as extensive research into potential therapies yields new options. In this article, the literature is reviewed to identify emerging therapies for advanced prostate cancer. Emphasis is placed on agents that have been approved in the United States of America (USA) and the European Union, or that have reached phase III clinical studies. Several new therapies have been approved in recent years across different stages of the natural history of the disease. Degarelix, a luteinizing hormone-releasing hormone antagonist, has been approved for reducing testosterone to castrate levels in hormone-sensitive disease. No new agents have been approved for use in combination with docetaxel chemotherapy, the current standard of care for metastatic castration-resistant prostate cancer. One immunotherapy, sipuleucel-T, has been approved (USA only) in the pre-docetaxel setting. Cabazitaxel, a next-generation taxane, and abiraterone acetate, an inhibitor of androgen biosynthesis, have both been approved as second-line agents following chemotherapy. Enzalutamide (MDV3100), an androgen receptor antagonist, has been shown to increase overall survival in the post-chemotherapy setting in metastatic disease. Denosumab, an antibody-based bone-targeted agent, has been approved for the prevention of skeletal-related events in patients with bone metastases. Radium-223 chloride, an α-emitting radiopharmaceutical, is likely to gain approval soon following promising results in a phase III trial. Clinical studies involving other promising agents are ongoing. The emergence of these therapies adds to the growing armamentarium against prostate cancer.

The effect of baseline testosterone on the efficacy of degarelix and leuprolide: further insights from a 12-month, comparative, phase III study in prostate cancer patients

OBJECTIVE

To investigate the effects of baseline testosterone on testosterone control and prostate-specific antigen (PSA) suppression using data from a phase III trial (CS21) comparing degarelix and leuprolide in prostate cancer.

METHODS

In CS21, patients with histologically confirmed prostate cancer (all stages) were randomized to degarelix 240 mg for 1 month followed by monthly maintenance doses of 80 or 160 mg, or leuprolide 7.5 mg/month. Patients receiving leuprolide could receive antiandrogens for flare protection. Treatment effects on testosterone and PSA reduction, testosterone surge, and microsurges were investigated in 3 baseline testosterone subgroups: <3.5, 3.5-5.0, and >5.0 ng/mL. Data are presented for the groups receiving degarelix 240/80 mg (the approved dose) and leuprolide 7.5 mg.

RESULTS

Higher baseline testosterone delayed castration with both treatments. However, castrate testosterone levels and PSA suppression occurred more rapidly with degarelix irrespective of baseline testosterone. With leuprolide, the magnitude of testosterone surge and microsurges increased with increasing baseline testosterone. There was no overall correlation between baseline testosterone and initial PSA decrease in either treatment group, although PSA suppression tended to be slowest with leuprolide and fastest with degarelix in the high baseline testosterone subgroup.

CONCLUSION

Patients with high baseline testosterone may have greater risk of tumor stimulation (clinical flare) and mini-flares during gonadotrophin-releasing hormone agonist treatment and so the need for flare protection with antiandrogens in these patients is obvious, especially in metastatic disease. Although higher baseline testosterone delays castration, castrate testosterone and PSA suppression occur more rapidly with degarelix, irrespective of baseline testosterone, without the need for flare protection.

Androgen deprivation therapy: past, present and future

Since Huggins and Hodges demonstrated the responsiveness of prostate cancer to androgen deprivation therapy (ADT), androgen-suppressing strategies have formed the cornerstone of management of advanced prostate cancer. Approaches to ADT have included orchidectomy, oestrogens, luteinizing hormone-releasing hormone (LHRH) agonists, anti-androgens and more recently the gonadotrophin-releasing hormone antagonists. The most extensively studied antagonist, degarelix, avoids the testosterone surge and clinical flare associated with LHRH agonists, offering more rapid PSA and testosterone suppression, improved testosterone control and improved PSA progression-free survival compared with agonists. The clinical profile of degarelix appears to make it a particularly suitable therapeutic option for certain subgroups of patients, including those with metastatic disease, high baseline PSA (>20 ng/mL) and highly symptomatic disease. As well as forming the mainstay of treatment for advanced prostate cancer, ADT is increasingly used in earlier disease stages. While data from clinical trials support the use of ADT neoadjuvant/adjuvant to radiotherapy for locally advanced or high-risk localized prostate cancer, it remains to be established whether specific ADT classes/agents provide particular benefits in this clinical setting.

Overcoming castration resistance in prostate cancer

PURPOSE OF REVIEW

Recent advances in our understanding of the androgen axis signaling pathway have led to the development of therapeutic strategies to overcome the state of 'castration resistance' in prostate cancer. In this review, we examine the mechanisms of castration resistance, as well as recently reported and ongoing clinical studies, which will further identify therapeutic opportunities for novel therapeutics targeting the androgen-signaling axis in advanced prostate cancer.

RECENT FINDINGS

As evidenced by recently reported positive phase III clinical trials, secondary hormonal agents such as abiraterone and MDV3100 may still be very effective in the treatment of castration-resistant prostate cancer, even after the use of docetaxel chemotherapy.

SUMMARY

Novel agents targeting this pathway have demonstrated a proof of principle that overcoming castration resistance is possible, leading to significant changes in the landscape of treatment in this disease. The optimal combination, sequence, and pattern of use in these novel therapies will be the focus of clinical research in the near future.

New considerations for ADT in advanced prostate cancer and the emerging role of GnRH antagonists

Androgen deprivation therapy (ADT) is first-line treatment for metastatic prostate cancer (PCa). Gonadotrophin-releasing hormone (GnRH) agonists are the most commonly used ADT but have several theoretical physiologic disadvantages (e.g. initial testosterone surge, potential microsurges upon repeat administration). Testosterone surge delays the intended serologic endpoint of testosterone suppression and may exacerbate clinical symptoms. GnRH antagonists were developed with a view toward overcoming these potential adverse physiologic events. This review evaluates GnRH agonists and antagonists, assessing the potential future role of antagonists in PCa and strategies to minimize ADT adverse events (AEs). Evidence was identified via PubMed search (by GnRH agent and other ADT-related terms), from review article bibliographies, and authors' therapy area knowledge, with articles included by author consensus. Degarelix shows similar efficacy to a GnRH agonist in achieving and maintaining castration, with faster onset and without testosterone surge/microsurges. Phase III data showed that, in the first treatment year, degarelix displayed a lower risk of PSA failure or death (composite endpoint), lower levels of the bone marker serum alkaline phosphatase (in baseline metastatic disease), and fewer musculoskeletal AEs than the agonist leuprolide. Also, crossing over from leuprolide to degarelix after 1 year reduced the risk of PSA failure or death. ADT displays an AE spectrum which can impact quality of life as well as causing significant morbidities. Strategies to improve ADT tolerability have become increasingly important including: a holistic management approach, improved diet and exercise, more specific monitoring to detect and prevent testosterone depletion toxicities, and intermittent ADT allowing hormonal recovery between treatment periods. Clinical studies suggest possible benefits of GnRH antagonists over agonists based on different mechanisms of action. GnRH antagonists should now be considered as an alternative first-line ADT option in advanced PCa. Intermittent ADT and a holistic treatment approach are promising strategies to improve ADT tolerability.

The efficacy and safety of degarelix, a GnRH antagonist: a 12-month, multicentre, randomized, maintenance dose-finding phase II study in Japanese patients with prostate cancer

OBJECTIVE

To assess the efficacy and safety of degarelix, a new gonadotropin-releasing hormone antagonist, for achieving and maintaining serum testosterone suppression (≤0.5 ng/ml) during the 12-month treatment of Japanese patients with prostate cancer.

METHODS

This Phase II study was conducted as a multicentre, randomized, parallel-group, open-label study. A total of 273 patients with adenocarcinoma of the prostate (any stage) were treated. Degarelix was administered subcutaneously at an initial dose of 240 mg followed by monthly maintenance doses of either 80 or 160 mg for a total of 12 doses. The treatment continued for 12 months.

RESULTS

Dose regimens of 240/80 and 240/160 mg maintained castrate levels of testosterone in 94.5 and 95.2% of the patients, respectively. After 3 days, 99.3 and 98.5% of the patients, respectively, reached these levels without a testosterone surge. Prostate-specific antigen levels decreased rapidly following degarelix administration and remained low throughout the study. Best overall response rates according to RECIST were 71.4 (20/28) and 72.7% (16/22), respectively. Eighteen patients (6.6%) withdrew from the study due to adverse events. The most common adverse events were injection site reactions; other adverse events included hot flush, nasopharyngitis, weight increase and pyrexia.

CONCLUSIONS

Both monthly degarelix dosing regimens were found to be effective in testosterone suppression without a testosterone surge, prostate-specific antigen reductions and anti-tumour effect in Japanese patients with prostate cancer, as was shown in the overseas Phase III study. Degarelix was also well tolerated.

Gonadotropin-releasing hormone: an update review of the antagonists versus agonists

Gonadotropin-releasing hormone agonists and antagonists provide androgen-deprivation therapy for prostate cancer. Unlike agonists, gonadotropin-releasing hormone antagonists have a direct mode of action to block pituitary gonadotropin-releasing hormone receptors. There are two licensed gonadotropin-releasing hormone antagonists, degarelix and abarelix. Of these, degarelix is the more extensively studied and has been documented to be more effective than the well-established, first-line agonist, leuprolide, in terms of substantially faster onset of castration, faster suppression of prostate-specific antigen, no risk for testosterone surge or clinical flare, and improved prostate-specific antigen progression-free survival, suggesting a delay in castration resistance. Other than minor injection-site reactions, degarelix is generally well tolerated, without systemic allergic reactions and with most adverse events consistent with androgen suppression or the underlying condition. In conclusion, degarelix provides a rational, first-line androgen-deprivation therapy suitable for the treatment of prostate cancer, with faster onset of castration than with agonists, and no testosterone surge. Furthermore, data suggest that degarelix improves disease control compared with leuprolide, and might delay the onset of castration-resistant disease. In view of these clinical benefits and the lack of need for concomitant anti-androgen treatment, gonadotropin-releasing hormone antagonists might replace gonadotropin-releasing hormone agonists as first-line androgen-deprivation therapy in the future.

Androgen deprivation therapy as adjuvant/neoadjuvant to radiotherapy for high-risk localised and locally advanced prostate cancer: recent developments

Androgen deprivation therapy (ADT) has traditionally formed the mainstay of treatment for advanced/metastatic prostate cancer (PCa); however, it is now also having an increasingly important role in earlier stages of disease. Indeed, in patients with locally advanced or high-risk localised disease, the addition of neoadjuvant and adjuvant hormone therapy is now considered the standard of care for those men treated with radical radiotherapy. Although luteinising hormone-releasing hormone (LHRH) agonists have been used for many years as ADT, they may be associated with clinical flare and testosterone breakthrough. Newer hormonal agents continue to be developed, such as gonadotropin-releasing hormone antagonists, which reduce testosterone and prostate-specific antigen levels more rapidly than LHRH agonists, without testosterone flare. This review examines ADT use in combination with radiotherapy to improve outcomes in localised or locally advanced disease, and examines some of the latest developments in hormonal therapy for PCa.

Obesity is associated with castration-resistant disease and metastasis in men treated with androgen deprivation therapy after radical prostatectomy: results from the SEARCH database

Study Type - Prognosis (cohort series). Level of Evidence 2a. What's known on the subject? and What does the study add? The incidence and prevalence of obesity in the USA and Europe is increasing. Higher body mass index is associated with a lower risk of overall prostate cancer diagnosis but also with an increased risk of high grade prostate cancer. Obese men undergoing primary therapy with radical prostatectomy or external beam radiation are more likely to experience a biochemical recurrence after treatment compared with normal weight men. Finally, obesity is associated with increased prostate-cancer-specific mortality. We hypothesized that obese men on androgen deprivation therapy may be at increased risk for prostate cancer progression. Previous studies have shown that obese men have lower levels of testosterone compared with normal weight men. Additionally, one previous study found that obese men have higher levels of testosterone on androgen deprivation therapy. Men with higher levels of testosterone on androgen deprivation therapy are at increased risk of prostate cancer progression. We found that men with higher body mass index were at increased risk of progression to castration-resistant prostate cancer, development of metastases and prostate-cancer-specific mortality. When we adjusted for various clinicopathological characteristics, obese men were at increased risk of progression to castration-resistant prostate cancer and development of metastases. The results of our study help generate hypotheses for further study regarding the mechanisms between obesity and aggressive prostate cancer.

OBJECTIVE

• To investigate whether obesity predicts poor outcomes in men starting androgen deprivation therapy (ADT) before metastasis, since previous studies found worse outcomes after surgery and radiation for obese men.

METHODS

• A retrospective review was carried out of 287 men in the SEARCH database treated with radical prostatectomy between 1988 and 2009. • Body mass index (BMI) was categorized to <25, 25-29.9 and ≥ 30 kg/m2. • Proportional hazards models were used to test the association between BMI and time to castration-resistant prostate cancer (PC), metastases and PC-specific mortality adjusting for demographic and clinicopathological data.

RESULTS

• During a median 73-month follow-up after radical prostatectomy, 403 men (14%) received early ADT. • Among 287 men with complete data, median BMI was 28.3 kg/m2. • Median follow-up from the start of ADT was 52 months during which 44 men developed castration-resistant PC, 34 developed metastases and 24 died from PC. • In multivariate analysis, higher BMI was associated with a trend for greater risk of progression to castration-resistant PC (P= 0.063), a more than threefold increased risk of developing metastases (P= 0.027) and a trend toward worse PC-specific mortality (P= 0.119). • Prognostic biomarkers did not differ between BMI groups.

CONCLUSIONS

• Among men treated with early ADT, our results suggest that obese men may have increased risk of PC progression. • These data support the general hypothesis that obesity is associated with aggressive PC, although validation of these findings and further study of the mechanisms linking obesity and poor PC outcomes are required.

[EAU guidelines on prostate cancer. Part II: treatment of advanced, relapsing, and castration-resistant prostate cancer]

OBJECTIVES

Our aim is to present a summary of the 2010 version of the European Association of Urology (EAU) guidelines on the treatment of advanced, relapsing, and castration-resistant prostate cancer (CRPC).

METHODS

The working panel performed a literature review of the new data emerging from 2007 to 2010. The guidelines were updated, and the levels of evidence (LEs) and/or grades of recommendation (GR) were added to the text based on a systematic review of the literature, which included a search of online databases and bibliographic reviews.

RESULTS

Luteinising hormone-releasing hormone (LHRH) agonists are the standard of care in metastatic prostate cancer (PCa). Although LHRH antagonists decrease testosterone without any testosterone surge, their clinical benefit remains to be determined. Complete androgen blockade has a small survival benefit of about 5%. Intermittent androgen deprivation (IAD) results in equivalent oncologic efficacy when compared with continuous androgen-deprivation therapy (ADT) in well-selected populations. In locally advanced and metastatic PCa, early ADT does not result in a significant survival advantage when compared with delayed ADT. Relapse after local therapy is defined by prostate-specific antigen (PSA) values > 0.2 ng/ml following radical prostatectomy (RP) and > 2 ng/ml above the nadir after radiation therapy (RT). Therapy for PSA relapse after RP includes salvage RT at PSA levels < 0.5 ng/ml and salvage RP or cryosurgical ablation of the prostate in radiation failures. Endorectal magnetic resonance imaging and 11C-choline positron emission tomography/computed tomography (CT) are of limited importance if the PSA is < 2.5 ng/ml; bone scans and CT can be omitted unless PSA is >20 ng/ml. Follow-up after ADT should include screening for the metabolic syndrome and an analysis of PSA and testosterone levels. Treatment of castration-resistant prostate cancer (CRPC) includes second-line hormonal therapy, novel agents, and chemotherapy with docetaxel at 75 mg/m(2) every 3 wk. Cabazitaxel as a second-line therapy for relapse after docetaxel might become a future option. Zoledronic acid and denusomab can be used in men with CRPC and osseous metastases to prevent skeletal-related complications.

CONCLUSION

The knowledge in the field of advanced, metastatic, and CRPC is rapidly changing. These EAU guidelines on PCa summarise the most recent findings and put them into clinical practice. A full version is available at the EAU office or online at www.uroweb.org.

A phase III extension trial with a 1-arm crossover from leuprolide to degarelix: comparison of gonadotropin-releasing hormone agonist and antagonist effect on prostate cancer

PURPOSE

We investigated the efficacy and safety of degarelix treatment and the effects of switching from leuprolide to degarelix in an ongoing extension study with a median 27.5-month followup of a pivotal 1-year prostate cancer trial.

MATERIALS AND METHODS

Patients who completed a 1-year pivotal phase III trial continued on the same monthly degarelix maintenance dose (160 or 80 mg in 125 each), or were re-randomized from leuprolide 7.5 mg to degarelix 240/80 mg (69) or 240/160 mg (65). Data are shown on the approved degarelix 240/80 mg dose. The primary end point was safety/tolerability and the secondary end points were testosterone, prostate specific antigen, luteinizing hormone and follicle-stimulating hormone responses, and prostate specific antigen failure and progression-free survival.

RESULTS

During followup testosterone and prostate specific antigen suppression were similar to those in the 1-year trial in patients who continued on degarelix or switched from leuprolide. The prostate specific antigen progression-free survival hazard rate was decreased significantly after the switch in the leuprolide/degarelix group while the rate in those who continued on degarelix was consistent with the rate in treatment year 1. The same hazard rate change pattern occurred in the group with baseline prostate specific antigen greater than 20 ng/ml. Adverse event frequency was similar between the groups and decreased with time.

CONCLUSIONS

Data support the statistically significant prostate specific antigen progression-free survival benefit for degarelix over leuprolide seen during year 1 and the use of degarelix as first line androgen deprivation therapy as an alternative to a gonadotropin-releasing hormone agonist.

[Innovations in hormonal treatment for locally advanced and/or metastatic prostate cancer]

Discovered over 40 years ago, hormonal therapy remains the cornerstone therapy of advanced prostate cancer and continues to evolve. Suppression of serum testosterone remains the mainstay of systemic treatment of prostate cancer. Antagonists of LH-RH are now available and can prevent the castration delay of agonists. They seem to have a clinical benefit in terms of PSA control. During the phase of resistance to extracellular castration, the androgen receptor is the dominant element. Intracellular steroidogenesis can be blocked by Abiraterone. Amplification and mutation of the androgen receptor may be controlled by antiandrogens of second generation. Thus, these new molecules, already or soon available, will renew the strategy of prostate cancer treatment.