Leuprolide acetate 1-, 3- and 6-monthly depot formulations in androgen deprivation therapy for prostate cancer in nine European countries: evidence review and economic evaluation

Polymer Delivery Systems for Long-Acting Antiretroviral Drugs

The success of long-acting (LA) drug delivery systems (DDSs) is linked to their biocompatible polymers. These are used for extended therapeutic release. For treatment or prevention of human immune deficiency virus type one (HIV-1) infection, LA DDSs hold promise for improved regimen adherence and reduced toxicities. Current examples include Cabenuva, Apretude, and Sunlenca. Each is safe and effective. Alternative promising DDSs include implants, prodrugs, vaginal rings, and microarray patches. Each can further meet patients' needs. We posit that the physicochemical properties of the formulation chemical design can optimize drug release profiles. We posit that the strategic design of LA DDS polymers will further improve controlled drug release to simplify dosing schedules and improve regimen adherence.

A review of clinical evidence to assess differences in efficacy and safety of luteinizing hormone-releasing hormone (LHRH) agonist (goserelin) and LHRH antagonist (degarelix)

Luteinizing hormone-releasing hormone agonist (LHRH-A), goserelin, and antagonist, degarelix, are both indicated for the treatment of advanced prostate cancer (PCa); however, large comparative trials evaluating their efficacy and safety are lacking. In this review, we assessed the available evidence for both the drugs. Although degarelix achieves an early rapid decline in testosterone (T) and prostate-specific antigen (PSA) levels, median T and PSA levels, in addition to prostate volume and International Prostate Symptom Scores, become comparable with goserelin over the remaining treatment period. Degarelix causes no initial flare, therefore it is recommended in patients with spinal metastases or ureteric obstruction. Goserelin achieves lower PSA, improved time to progression, and better survival outcomes when administered adjunctively to radiotherapy compared with radiotherapy alone, with significant results even over long-term follow-up. The evidence supporting adjuvant degarelix use is limited. Goserelin has better injection site safety, single-step delivery, and an efficient administration schedule compared with degarelix, which has significantly higher injection site reactions and less efficient administration mechanism. There is conflicting evidence about the risk of cardiovascular disease (CVD), and caution is required when using LHRH-A in patients with preexisting CVD. There is considerable long-term evidence for goserelin in patients with advanced PCa, with degarelix being a more recent option. The available comparative evidence of goserelin versus degarelix has several inherent limitations related to study design, sample size, conduct, and statistical analyses, and hence warrants robust prospective trials and long-term follow-up.

Evaluating parameters affecting drug fate at the intramuscular injection site

Intramuscular (IM) injections are a well-established method of delivering a variety of therapeutics formulated for parenteral administration. While the wide range of commercial IM pharmaceuticals provide a wealth of pharmacokinetic (PK) information following injection, there remains an inadequate understanding of drug fate at the IM injection site that could dictate these PK outcomes. An improved understanding of injection site events could improve approaches taken by formulation scientists to identify therapeutically effective and consistent drug PK outcomes. Interplay between the typically non-physiological aspects of drug formulations and the homeostatic IM environment may provide insights into the fate of drugs at the IM injection site, leading to predictions of how a drug will behave post-injection in vivo. Immune responses occur by design after e.g. vaccine administration, however immune responses post-injection are not in the scope of this article. Taking cues from existing in vitro modelling technologies, the purpose of this article is to propose "critical parameters" of the IM environment that could be examined in hypothesis-driven studies. Outcomes of such studies might ultimately be useful in predicting and improving in vivo PK performance of IM injected drugs.

Effectiveness of a 6-Month 22.5-mg Leuprolide Acetate Depot Formulation With Tamoxifen for Postoperative Premenopausal Estrogen Suppression in Hormone Receptor-Positive Breast Cancer

Background

In patients with hormone receptor-positive (HR+)/premenopausal breast cancer, luteinizing hormone-releasing hormone analogs (LHRHas) are used as standard endocrine treatment. Based on previous clinical studies, 1-month formulations are recommended in most breast cancer treatment guidelines, but long-acting formulations facilitate reductions in side effects and patient discomfort caused by frequent administration. However, few efficacy studies have been conducted on 6-month formulations. Therefore, this study aimed to evaluate the efficacy of 6-month formulations of LHRHas.

Methods

This retrospective study was conducted from January 2018 to December 2019 and involved premenopausal patients with HR+ breast cancer administered 6-month LHRHas as adjuvant treatment after surgery, and those previously administered chemotherapy or other LHRHa types were excluded. Patients’ estradiol (E2) and follicle-stimulating hormone (FSH) levels were measured before surgery, and their E2 levels were also measured at 3, 6, 12, 18, and 24 months at periodic postsurgical examinations.

Results

A total of 228 patients were included, and the median patient age was 44 (range, 25–54) years. The mean serum E2 and FSH levels before surgery were 69.7 (range, 4–683) pg/mL and 7.3 (range, 0.4–88.9) mIU/mL, respectively, whereas the mean serum E2 level monitored at intervals during the 6-month LHRHa administration was 5.5 (range, 4.0–52) pg/mL. No women menstruated during the follow-up period after the LHRHas administration, and the E2 levels were less than 30 pg/mL in all patients except one.

Conclusions

The 6-month LHRHa formulation adequately suppressed ovarian function in premenopausal patients with HR+ breast cancer. This indicates that long-acting LHRHas can be effectively used for patient convenience and that there is high compliance with long-term use.

Behavioral and neurobiological effects of GnRH agonist treatment in mice-potential implications for puberty suppression in transgender individuals

In the United States, ~1.4 million individuals identify as transgender. Many transgender adolescents experience gender dysphoria related to incongruence between their gender identity and sex assigned at birth. This dysphoria may worsen as puberty progresses. Puberty suppression by gonadotropin-releasing hormone agonists (GnRHa), such as leuprolide, can help alleviate gender dysphoria and provide additional time before irreversible changes in secondary sex characteristics may be initiated through feminizing or masculinizing hormone therapy congruent with the adolescent's gender experience. However, the effects of GnRH agonists on brain function and mental health are not well understood. Here, we investigated the effects of leuprolide on reproductive function, social and affective behavior, cognition, and brain activity in a rodent model. Six-week-old male and female C57BL/6J mice were injected daily with saline or leuprolide (20 μg) for 6 weeks and tested in several behavioral assays. We found that leuprolide increases hyperlocomotion, changes social preference, and increases neuroendocrine stress responses in male mice, while the same treatment increases hyponeophagia and despair-like behavior in females. Neuronal hyperactivity was found in the dentate gyrus (DG) of leuprolide-treated females, but not males, consistent with the elevation in hyponeophagia and despair-like behavior in females. These data show for the first time that GnRH agonist treatment after puberty onset exerts sex-specific effects on social- and affective behavior, stress regulation, and neural activity. Investigating the behavioral and neurobiological effects of GnRH agonists in mice will be important to better guide the investigation of potential consequences of this treatment for youth experiencing gender dysphoria.

Timeline of Translational Formulation Technologies for Cancer Therapy: Successes, Failures, and Lessons Learned Therefrom

Over the past few decades, the field of cancer therapy has seen a significant change in the way in which formulations are designed and developed, resulting in more efficient products that allow us to ultimately achieve improved drug bioavailability, efficacy, and safety. However, although many formulations have entered the market, many others have fallen by the wayside leaving the scientific community with several lessons to learn. The successes (and failures) achieved with formulations that have been approved in Europe and/or by the FDA for the three major types of cancer therapy (peptide-based therapy, chemotherapy, and radiotherapy) are reviewed herein, covering the period from the approval of the first prolonged-release system for hormonal therapy to the appearance of the first biodegradable microspheres intended for chemoembolization in 2020. In addition, those products that have entered phase III clinical trials that have been active over the last five years are summarized in order to outline future research trends and possibilities that lie ahead to develop clinically translatable formulations for cancer treatment.

Efficacy of Leuprorelide acetate (Eligard®) in daily practice in Brazil: a retrospective study with depot formulations in patients with prostate cancer

Introduction:

Androgen deprivation therapy (ADT) is the mainstay of therapy for advanced prostate cancer. Studies addressing the efficacy of different depot formulations of long acting luteinizing hormone releasing hormone agonists in the Brazilian population are lacking. We aimed to compare the efficacy of three schedules of leuprolide acetate in lowering PSA in a real world population.

Materials and Methods:

We reviewed the medical records of patients with prostate cancer seen at our institution between January 2007 and July 2018. We analyzed patients treated with long-acting leuprolide acetate and grouped these patients into three strata according to the administration of ADT every 1, 3 or 6 months. The primary outcome was the serum prostate specific antigen (PSA) levels at 6 and 12 months after treatment initiation. We used Friedman test to compare the distribution of PSA levels at baseline and at 6 and 12 months within each treatment stratum. We considered two-sided P values <0.05 as statistically significant. We analyzed toxicity descriptively.

Results:

We analyzed a total of 932 patients, with a median age of 72 years and a median time since diagnosis of prostate cancer of 8.5 months. ADT was administered monthly in 115 patients, quarterly in 637, and semiannually in 180. Nearly half of the patients had locally advanced disease. In comparison with baseline, median serum PSA levels were reduced at 12 months by at least 99.7% in the three strata (P <0.001 in all cases). Sexual impotence and hot flashes were the most frequently reported toxicities.

Conclusion:

To our knowledge, this is the largest assessment of real-world data on alternative schedules of leuprolide in a Brazilian population. Our study suggests that PSA levels can be effectively be reduced in most patients treated with monthly, quarterly, or semiannual injections of long-acting leuprolide acetate.

Indications and Complications of Androgen Deprivation Therapy

OBJECTIVE

To review the indications for and side effects of androgen deprivation therapy (ADT) in men affected by prostate cancer.

DATA SOURCES

National guidelines, evidence-based summaries, peer-reviewed studies, and websites.

CONCLUSION

Indications for ADT include men with (1) intermediate- to high-risk localised prostate cancer undergoing radiation therapy, (2) biochemical recurrence after radical prostatectomy treated with salvage radiation therapy, or (3) metastatic prostate cancer. Several forms of ADT are available. To support self-management, body weight, diet, physical activity, alcohol consumption, and smoking should be discussed during clinical consultations. Important side effects of ADT may include flare-up phenomena of GnRH analogues, local reactions at injection sites, cardiovascular events, bone loss/fractures, drug-drug interactions, urinary tract dysfunction, hot flashes, cognitive impairment, seizure falls, and liver impairment.

IMPLICATIONS FOR NURSING PRACTICE

Nurses have a role in personalized cancer care and should be familiar with indications, side effects, and interventions to optimize quality of life for men affected by prostate cancer receiving ADT.

Practical strategies to manage cancer patients during the COVID-19 pandemic: Saudi Oncology Pharmacy Assembly Experts recommendations

Purpose

During COVID-19 pandemic, cancer patients are considered one of the most vulnerable to infection since they tend to have advanced age, multiple comorbidities, and are often immunosuppressed by their cancer or therapy. Hence, the Saudi Oncology Pharmacy Assembly has issued recommendations to reduce the frequency of cancer patients’ visits to oncology centers during the pandemic while maintaining the access to cancer therapy and minimize the risk of exposure to coronavirus disease.

Materials and methods

A qualitative methodological approach was conducted in April 2020 using a virtual panel discussion for collection of recommendations.

Results

A total of 12 expert oncology pharmacy practitioners shared their knowledge and experiences in managing oncology patients during the COVID-19 pandemic. The participants recognized many fundamental recommendations that were already applied in many cancer centers since the start of the COVID-19 outbreak. On that basis, the panelists developed eight practice-related recommendations for action, with a main focus on cancer treatment modification.

Conclusions

In conclusion, delivering cancer care during the COVID-19 pandemic carries significant challenges. This paper addressed suggestions to properly manage cancer patients during difficult times. Implementing changes in practice mandates a national collaborative effort from different sectors to guarantee the quality and continuity of care. The SOPA expert panel developed these recommendations, to ultimately contribute in maintaining access to cancer therapy while minimizing the risk of COVID-19 exposure.

Nanomedicines - Tiny particles and big challenges

After decades of research, nanotechnology has been used in a broad array of biomedical products including medical devices, drug products, drug substances, and pharmaceutical-grade excipients. But like many great achievements in science, there is a fine balance between the risks and opportunities of this new technology. Some materials and surface structures in the nanosize range can exert unexpected toxicities and merit a more detailed safety assessment. Regulatory agencies such as the United States Food and Drug Administration or the European Medicines Agency have started dealing with the potential risks posed by nanomaterials. Considering that a thorough characterization is one of the key aspects of controlling such risks this review presents the regulatory background of nanosafety assessment and provides some practical advice on how to characterize nanomaterials and drug formulations. Further, the challenges of how to maintain and monitor pharmaceutical quality through a highly complex production processes will be discussed.

Nanopharmaceuticals and nanomedicines currently on the market: challenges and opportunities

There has been a revolution in nanotechnology and nanomedicine. Since 1980, there has been a remarkable increase in approved nano-based pharmaceutical products. These novel nano-based systems can either be therapeutic agents themselves, or else act as vehicles to carry different active pharmaceutical agents into specific parts of the body. Currently marketed nanostructures include nanocrystals, liposomes and lipid nanoparticles, PEGylated polymeric nanodrugs, other polymers, protein-based nanoparticles and metal-based nanoparticles. A range of issues must be addressed in the development of these nanostructures. Ethics, market size, possibility of market failure, costs and commercial development, are some topics which are on the table to be discussed. After passing all the ethical and biological assessments, and satisfying the investors as to future profitability, only a handful of these nanoformulations, successfully obtained marketing approval. We survey the range of nanomedicines that have received regulatory approval and are marketed. We discuss ethics, costs, commercial development and possible market failure. We estimate the global nanomedicine market size and future growth. Our goal is to summarize the different approved nanoformulations on the market, and briefly cover the challenges and future outlook.

Effects of Initiating or Switching to a Six-Monthly Triptorelin Formulation on Prostate Cancer Patient-Healthcare Interactions and Hospital Resource Use: a Real-World, Retrospective, Non-Interventional Study

INTRODUCTION

Luteinising hormone-releasing hormone agonist (LHRHa) injections are currently used in the treatment of advanced prostate cancer, but the frequency of injections may represent a burden to patients and healthcare services. The aim of this study was to collect real-world evidence about clinical and practical outcomes for patients with prostate cancer initiating six-monthly triptorelin, or switching from shorter-acting formulations to six-monthly triptorelin, in hospitals in the DEcapeptyl SERVice Evaluation project.

METHODS

Up to 2 years of data were collected retrospectively by physicians from records of 88 patients receiving six-monthly triptorelin at three centres. The primary outcome measure was the change in the number of patient-healthcare interactions (patient reviews, prostate-specific antigen (PSA) tests, and LHRHa injections) over a 24-month treatment period.

RESULTS

This analysis included 47 patients newly initiated on six-monthly triptorelin and 41 who received 12 months of a one- or three-monthly LHRHa before switching to six-monthly triptorelin. After switching to six-monthly triptorelin, there was a statistically significant reduction in patient reviews (46.8%), injections (46.8%), and PSA tests (26.6%; all P < 0.0001). The total number of patient-healthcare interactions was significantly reduced (41.5%; P < 0.0001). Based upon cost of these interactions only, the cost reduction of switching to six-monthly triptorelin was £10,214.85 (£249.14 per patient) over 12 months. At 12 months, median PSA was 1.30 ng/mL (23.50 ng/mL at diagnosis) for newly treated patients and 0.24 ng/mL (0.35 ng/mL at switch) for patients who had switched treatment. No safety issues were identified.

CONCLUSION

Switching from one- or three-monthly LHRHa to six-monthly triptorelin significantly reduced patient-healthcare interactions and associated costs while maintaining PSA control over a 12-month treatment period. This not only translates into healthcare savings but may release men from the restriction of repeated healthcare interactions and thus improve the overall patient experience as the population of long-term prostate cancer survivors continues to increase.

FUNDING

Ipsen Limited.

Recent advances in "smart" delivery systems for extended drug release in cancer therapy

Advances in nanomedicine have become indispensable for targeted drug delivery, early detection, and increasingly personalized approaches to cancer treatment. Nanoparticle-based drug-delivery systems have overcome some of the limitations associated with traditional cancer-therapy administration, such as reduced drug solubility, chemoresistance, systemic toxicity, narrow therapeutic indices, and poor oral bioavailability. Advances in the field of nanomedicine include “smart” drug delivery, or multiple levels of targeting, and extended-release drug-delivery systems that provide additional methods of overcoming these limitations. More recently, the idea of combining smart drug delivery with extended-release has emerged in hopes of developing highly efficient nanoparticles with improved delivery, bioavailability, and safety profiles. Although functionalized and extended-release drug-delivery systems have been studied extensively, there remain gaps in the literature concerning their application in cancer treatment. We aim to provide an overview of smart and extended-release drug-delivery systems for the delivery of cancer therapies, as well as to introduce innovative advancements in nanoparticle design incorporating these principles. With the growing need for increasingly personalized medicine in cancer treatment, smart extended-release nanoparticles have the potential to enhance chemotherapy delivery, patient adherence, and treatment outcomes in cancer patients.

Are all gonadotrophin-releasing hormone agonists equivalent for the treatment of prostate cancer? A systematic review

To review direct comparative studies of the gonadotrophin-releasing hormone (GnRH) agonists goserelin, triptorelin, and leuprorelin for the treatment of prostate cancer, and identify whether there are meaningful clinical differences between these agents. In June 2017, the following searches were performed independently by two reviewers in PubMed: (i) 'prostate cancer' and 'triptorelin' and 'leuprorelin', (ii) 'prostate cancer' and 'triptorelin' and 'goserelin', and (iii) 'prostate cancer' and 'goserelin' and 'leuprorelin', without time restriction. Duplicates were deleted. Relevant conference abstracts were also screened. A total of 16 direct comparative trials were identified: 12 reported on efficacy outcomes, four on safety/tolerability, and five on the convenience of administration/user perceptions. These studies are restricted in terms of patient numbers, formulations assessed, and endpoints measured; none were adequately powered for survival outcome measures. Studies reporting on efficacy endpoints did not show major differences in the ability of these GnRH agonists to reduce levels of testosterone or prostate-specific antigen. Some studies suggest differences in short- or long-term testosterone control, the rate of injection site adverse events, and patient/healthcare professional perceptions, but definitive conclusions cannot be drawn from the existing evidence. Few direct comparative trials of GnRH agonists have been conducted. Whilst GnRH agonists provide a similar castration effect, there is not enough evidence to show that GnRH agonists are equivalent.

Practical differences between luteinizing hormone-releasing hormone agonists in prostate cancer: perspectives across the spectrum of care

BACKGROUND

Androgen deprivation therapy (ADT) with luteinizing hormone-releasing hormone (LHRH) agonists is well established for the treatment of men with metastatic prostate cancer. As clear differences in efficacy, safety, or tolerability between the available LHRH agonists are lacking, the healthcare management team needs to look to practical differences between the formulations when selecting therapy for their patients. Moreover, as the economic burden of prostate cancer rises alongside earlier diagnosis and improved survival, the possibility for cost savings by using products with specific features is growing in importance.

METHODS

A review was conducted to summarize the information on the different LHRH agonist formulations currently available and offer insight into their relative benefits and disadvantages from the perspectives of physicians, a pharmacist, and a nurse.

RESULTS

The leuprorelin acetate and goserelin acetate solid implants have the advantage of being ready to use with no requirement for refrigeration, whereas powder and microsphere formulations have to be reconstituted and have specific storage or handling constraints. The single-step administration of solid implants, therefore, has potential to reduce labor time and associated costs. Dosing frequency is another key consideration, as administering the injection provides an opportunity for face-to-face interaction between the patient and healthcare professionals to ensure therapy is optimized and give reassurance to patients. Prostate cancer patients are reported to prefer 3- or 6-monthly dosing, which aligns with the monitoring frequency recommended in European Association of Urology guidelines and has been shown to result in reduced annual costs compared with 1-month formulations.

CONCLUSIONS

A number of practical differences exist between the different LHRH agonist preparations available, which may impact on clinical practice. It is important for healthcare providers to be aware and carefully consider these differences when selecting treatments for their prostate cancer patients.

Injectable formulations of poly(lactic acid) and its copolymers in clinical use

Poly(lactic acid) and its copolymers have revolutionized the field of drug delivery due to their excellent biocompatibility and tunable physico-chemical properties. These copolymers have served the healthcare sector by contributing many products to combat various diseases and for biomedical applications. This article provides a comprehensive overview of clinically used products of poly(lactic acid) and its copolymers. Multi-dimension information covering product approval, formulation aspects and clinical status is described to provide a panoramic overview of each product. Moreover, leading patented technologies and various clinical trials on these products for different applications are included. This review focuses on marketed injectable formulations of PLA and its copolymers.

Androgen deprivation therapy with Leuprolide acetate for treatment of advanced prostate cancer

INTRODUCTION

Hormone sensitive advanced prostate cancer (PCa) is an incurable disease that is treated with a variety of hormonal therapies targeting the androgen/androgen receptor signaling axis. For decades androgen deprivation therapy (ADT) by surgical or chemical castration is the gold standard for the treatment of advanced PCa. Areas covered: This review discusses the pharmacological features of Leuprolide, a luteinizing hormone-releasing hormone (LHRH) agonists/analog and the most commonly used drug in ADT. Expert opinion: Although Leuprolide has been on the market for more than 30 years it is still the leading option for ADT and serves as a basis for most multimodal therapy concepts. The fact that with the onset of castration-resistance in late stage metastatic disease, a prolongation of ADT in combination with a second line hormonal manipulation is recommended supports the importance of the compound for daily clinical practice.

Extended release, 6-month formulations of leuprolide acetate for the treatment of advanced prostate cancer: achieving testosterone levels below 20 ng/dl

INTRODUCTION

Luteinizing hormone-releasing hormone agonists such as leuprolide acetate (LA) are the most frequently utilized treatment of advanced prostate cancer as the regimen for achieving androgen deprivation therapy (ADT). The efficacy of LA is determined by extent of testosterone (T) suppression in prostate cancer patients. Although, the historical castrate T suppression target has been defined as < 50 ng/dl, this level may not be as low as required to deliver equivalent suppression as achieved by surgical castration. Recent studies have demonstrated that a T level as low as 20 ng/dl may produce improved clinical outcomes.

AREAS COVERED

LA is available in long-acting formulations that deliver active drug over the course of 1-6 months from a single-dose administration. The technologies utilized to provide sustained drug delivery differ: one mode of administration uses microspheres, which encapsulate the drug and are injected as a suspension intramuscularly; another mode of administration uses a liquid polymer that creates a single, solid depot after injection subcutaneously. This article will review the safety and efficacy of both 6-month LA formulations, as well as their impact in prostate cancer treatment.

EXPERT OPINION

As the understanding of optimal T castrate level evolves and may be refined pending new data from contemporaneous trials, achievement and maintenance of T levels well below 50 ng/dl may be important in evaluating potential differences in ADT regimens.

Efficacy of triptorelin pamoate 11.25 mg administered subcutaneously for achieving medical castration levels of testosterone in patients with locally advanced or metastatic prostate cancer

OBJECTIVES

Gonadotropin-releasing hormone agonists are widely used as androgen deprivation therapy in many men with locally advanced or metastatic prostate cancer. Gonadotropin-releasing hormone agonists are delivered by intramuscular injection every 1, 3 or 6 months, but in some patients subcutaneous injection may be more appropriate. This study assessed the efficacy and safety profile of the gonadotropin-releasing hormone agonist, triptorelin pamoate, when administered by the subcutaneous route.

METHODS

In this multicentre, open-label, single-arm study, androgen deprivation therapy-naïve men with locally advanced or metastatic prostate cancer received the gonadotropin-releasing hormone agonist triptorelin pamoate 11.25 mg (3-month formulation) by the subcutaneous route twice (at baseline and 13 weeks later). The co-primary efficacy endpoints were the proportion of patients with a castration level of serum testosterone (<50 ng/dl) after 4 weeks, and of these, those still castrated after 26 weeks.

RESULTS

Of the 126 treated patients, 123 [97.6%; 95% confidence interval (CI): 93.2-99.5)] were castrated 4 weeks after the first subcutaneous injection, and 115/119 patients (96.6%; 95% CI: 91.6-99.1) castrated at 4 weeks maintained castration at 26 weeks. Median prostate-specific antigen levels were reduced by 64.2 and 96.0% at 4 and 26 weeks, respectively. The probability of maintaining a testosterone level <20 ng/dl up to 26 weeks was 90.0% (95% CI: 85.0-95.0). The most frequently occurring treatment-related adverse events were typical of gonadotropin-releasing hormone agonist treatment (hot flushes, increased weight, erectile dysfunction and hyperhidrosis).

CONCLUSIONS

This study demonstrates that triptorelin pamoate 11.25 mg administered by the subcutaneous route every 3 months is as efficacious and well tolerated as administration via the intramuscular route in men with locally advanced or metastatic prostate cancer.