Selective Androgen Receptor Modulators-Transformative Drugs or Heralds of the Next Drug Epidemic?

This Viewpoint examines whether selective androgen receptor modulators have the potential to be transformative drugs or whether they herald the next drug epidemic.

Combination of docetaxel versus nonsteroidal antiandrogen with androgen deprivation therapy for high-volume metastatic hormone-sensitive prostate cancer: a propensity score-matched analysis.

PURPOSE: The aim of this study was to investigate the oncologic efficacy of combining docetaxel with androgen deprivation therapy (ADT) versus nonsteroidal antiandrogen (NSAA) with ADT in patients with high-volume metastatic hormone-sensitive prostate cancer (mHSPC) with focus on the effect of sequential therapy in a real-world clinical practice setting. METHODS: The records of 382 patients who harbored high-volume mHSPC, based on the CHAARTED criteria, and had received ADT with either docetaxel (n = 92) or NSAA (bicalutamide) (n = 290) were retrospectively analyzed. The cohorts were matched by one-to-one propensity scores based on patient demographics. Overall survival (OS), cancer-specific survival (CSS), progression-free survival (PFS), including time to castration-resistant prostate cancer (CRPC), and time to second-line progression (PFS2) were compared. 2nd-line PFS defined as the time from CRPC diagnosis to progression after second-line therapy was also compared. RESULTS: After matching, a total of 170 patients were retained: 85 patients treated with docetaxel + ADT and 85 patients treated with NSAA + ADT. The median OS and CSS for docetaxel + ADT versus NSAA + ADT were not reached (NR) vs. 49 months (p = 0.02) and NR vs. 55 months (p = 0.02), respectively. Median time to CRPC and PFS2 in patients treated with docetaxel + ADT was significantly longer compared to those treated with NSAA (22 vs. 12 months; p = 0.003 and, NR vs. 28 months; p < 0.001, respectively). There was no significant difference in 2nd-line PFS between the two groups. CONCLUSIONS: Our analysis suggested that ADT with docetaxel significantly prolonged OS and CSS owing to a better time to CRPC and PFS2 in comparison to NSAA + ADT in high-volume mHSPC.

[Apalutamide, Erleada®]. / Le Médicament du mois. Apalutamide, Erleada®.

Androgen-deprivation therapy (ADT), either bilateral orchiectomy or treatment with a gonadotropin-releasing hormone analogue agonist or antagonist, is the mainstay of treatment for advanced prostate cancer. In the metastatic setting, although ADT is initially effective, castration-resistant disease eventually develops in almost all men with prostate cancer. Since 2015, the addition of docetaxel, abiraterone, enzalutamide, apalutamide or darolutamide with docetaxel to ADT has been shown to improve overall survival (OS) of patients starting ADT for metastatic disease. Castration resistance occurs when disease progresses despite testosterone in the castrate range most commonly with or, more rarely, without detectable metastases. The addition of next-generation antiandrogens to ADT has been shown to improve OS in patients with high-risk nonmetastatic castration-resistant prostate cancer (nmCRPC) identified by a PSA doubling time (DT) ? 10 months. Apalutamide is a nonsteroidal antiandrogen agent that binds directly to the ligand-binding domain of the androgen receptor without agonist activity. When added to ADT apalutamide has been shown to improve OS by 35 % in patients starting ADT for metastatic prostate cancer both in patients with upfront metastatic disease or after previous treatment with curative intent. Similarly apalutamide has been shown to provide a 14-month OS improvement in patients with nmCRPC and short PSA DT. These OS benefits were obtained at no cost in terms of quality of life. Apalutamide is given orally once a day and is well tolerated. The most common side effects are fatigue, rash, hypertension and hot flushes. Potential interactions with concomitant medication should be taken into account.

La privation androgénique, chimique au moyen d'agonistes ou d'antagonistes de la LHRH, ou chirurgicale par orchidectomie, est un élément essentiel du traitement du cancer de la prostate avancé. Chez les patients métastatiques, son efficacité est cependant transitoire et une progression survient invariablement. Depuis 2015, une amélioration de la survie des patients métastatiques devant débuter une privation androgénique a été démontrée par l'instauration précoce soit d'une chimiothérapie par docétaxel, soit d'une hormonothérapie de nouvelle génération telle que l'abiratérone, l'enzalutamide, l'apalutamide, voire un traitement combinant docétaxel et darolutamide. Lorsque les patients progressent en dépit de la privation androgénique, on les dit résistants à la castration, le plus souvent en présence de métastases mais parfois en l'absence de lésion secondaire identifiable. Dans le cas des patients non métastatiques résistant à la castration à risque élevé d'évolution défavorable en raison d'un temps de doublement du PSA ? 10 mois, on a également démontré que l'ajout d'un anti-androgène de nouvelle génération améliorait la survie globale des patients. L'apalutamide, ou Erleada®, est un inhibiteur sélectif du récepteur aux androgènes, sans activité agoniste, administré par voie orale. Son instauration, en même temps que la privation androgénique, permet de réduire de 35 % la mortalité des patients métastatiques d'emblée ou secondairement après un traitement initial à visée curative. De même, l'apalutamide permet d'augmenter de 14 mois la survie des patients non métastatiques résistant à la castration à risque élevé d'évolution défavorable. Ces améliorations de la survie globale ont été obtenues sans détérioration de la qualité de vie. L'Erleada® est globalement bien toléré, et facile à administrer, s'agissant d'une prise orale unique quotidienne. La fatigue, la toxicité cutanée souvent modérée, l'hypertension artérielle et les bouffées de chaleur sont les effets secondaires les plus fréquents. Il convient également d'être attentif aux interactions médicamenteuses potentielles.

Treatment and trials in non-metastatic castration-resistant prostate cancer.

Metastatic prostate cancer is associated with considerable morbidity and mortality. Standard treatment for non-metastatic prostate cancer, to prevent metastatic progression, is androgen deprivation therapy (ADT); however, many patients will eventually develop castration-resistant prostate cancer (CRPC), which can prove challenging to treat. Between the stages of non-metastatic androgen-sensitive disease and metastatic CRPC is an intermediate disease state that has been termed non-metastatic CRPC (nmCRPC), which is a heterogeneous, man-made disease stage that occurs after a patient who has no radiological evidence of metastasis shows evidence of cancer progression even after ADT. Awareness of nmCRPC has risen owing to an increased use of ADT and its eventual failure. Men with nmCRPC are at a high risk of progression to mCRPC, with historically few options to halt this process. However, in the past two decades, multiple therapies have been investigated for the treatment of nmCRPC, including endothelin receptor antagonists and bone-targeted therapies, but none has changed the standard of care. In the past decade, the efficacy of androgen receptor pathway-targeting modalities has been investigated. Three novel nonsteroidal antiandrogen agents for treating high-risk nmCRPC have been investigated; the PROSPER, SPARTAN and ARAMIS trials were phase III, randomized, placebo-controlled clinical trials that investigated the efficacy and safety of enzalutamide, apalutamide and darolutamide, respectively. All three therapeutics showed statistically significant improvements in metastasis-free survival, progression to antineoplastic therapy was lengthened and at final analysis, overall survival was significantly improved. The comparative efficacy and safety of all three agents has not yet been investigated in a comprehensive clinical trial, but approval of these medications by the FDA and other regulatory agencies means that providers now have three effective therapeutic options to augment ADT for patients with nmCRPC.

Timing of androgen deprivation monotherapy and combined treatments in castration-sensitive and castration-resistant prostate cancer: a narrative review.

PURPOSE: Standard androgen deprivation therapy (ADT) can be initiated early at the time of diagnosis in asymptomatic castration-sensitive advanced prostate cancer. This definition has recently been expanded to also include an early combined treatment with standard ADT and new antihormonal drugs. We aimed to present the best available evidence for the timing of initiation of ADT monotherapy and combined treatments in castration-sensitive/-resistant prostate cancer. METHODS: For this narrative review, we searched Cochrane reviews in the Cochrane Library, systematic reviews and randomized controlled trials in MEDLINE, phase III and ongoing trials in ClinicalTrials.gov and screened the reference lists to extract articles of interest. One author screened the references which were finally included after assessing their relevance through discussion with other experts in the field. RESULTS: The identified references were grouped by medication (standard ADT, androgen biosynthesis inhibitor, androgen receptor antagonists or combined therapies) and tumor stage (castration sensitive or resistant). The evidence was narratively summarized and discussed in the context of the current therapeutic landscape. CONCLUSIONS: Early standard ADT can reduce symptoms of disease progression and may extend progression-free and overall survival. The patient should be well informed about the higher rates of treatment-related side effects. Deferring standard ADT might be indicated only for well-informed or unfit patients. Early standard ADT is increasingly combined with new antihormonal drugs in castration-sensitive metastatic prostate cancer to gain additional survival and quality of life benefits. Combined treatment at the time of development of castration-resistant disease is well established.

Efficacy and Safety of Non-Steroidal Anti-Androgens in Patients with Metastatic Prostate Cancer: Meta-Analysis of Randomized Controlled Trials.

BACKGROUND: Prostate cancer (PCa) is the sixth primary cause of cancer death. However, conflicts are present about the efficacy and safety of Non-steroidal anti-androgens (NSAA) for its treatment. The aim of this study was to assess the efficacy and safety of NSAAs versus any comparator for the treatment of advanced or metastatic PCa (mPCa). METHODS: MEDLINE and the Cochrane Library were searched. References of included studies and clinicaltrials.gov were also searched for relevant studies. Only English language studies after 1990 were considered for review. Randomized controlled trials (RCTs) examining the efficacy and safety of NSAAs as compared with any other comparator including surgery or chemotherapy in mPCa patients were included. The outcomes include efficacy, safety and the tolerability of the treatment. The Cochrane Risk of Bias Assessment Tool was used for quality assessment. Two authors were independently involved in the selection, extraction and quality assessment of included studies and disagreements were resolved by discussion or by consulting a third reviewer. RESULTS: Fifty-eight out of 1307 non-duplicate RCTs with 29154 patients were considered for the review. NSAA showed significantly better progression-free survival [PFS] (Hazard ratio [HR], 0.60; 95% confidence interval [CI], 0.46-0.78; P=0.0001), time to distant metastasis or death [TTD] (HR, 0.80; 95% CI 0.73-0.91; P<0.0001), objective response (Odds ratio [OR], 1.64; 95% CI 1.06-2.54; P=0.03) and clinical benefits (OR, 1.33; 95% CI 1.08-1.63; P=0.006) as compared to the control group. There was no significant difference observed between the groups in terms of overall survival (HR, 0.95; 95%CI, 0.87-1.03; P=0.18) and time to progression (HR, 0.93; 95% CI 0.77-1.11; P=0.43). Treatment-related adverse events were more with the NSAA group, but the discontinuation due to lack of efficacy reason was 43% significantly lesser than the control group in patients with mPCa. Rest of the outcomes were appeared to be non-significant. CONCLUSION: Treatment with NSAA was appeared to be better efficacious with respect to PFS, TTD, and response rate with considerable adverse events when compared to the control group in patients with metastatic PCa.

Prior switching to a second-line nonsteroidal antiandrogen does not impact the therapeutic efficacy of abiraterone acetate in patients with metastatic castration-resistant prostate cancer: a real-world retrospective study.

Even in the era of novel targeted agents, switching to a second-line nonsteroidal antiandrogen (NSAA) is still widely used in treating metastatic castration-resistant prostate cancer (mCRPC), especially in undeveloped countries. However, whether prior treatment with a second-line NSAA would impact the efficacy of abiraterone acetate (Abi) remains uncertain. In the current study, 87 mCRPC patients treated with Abi were analyzed. Among them, 21 were treated with a second-line NSAA (from bicalutamide to flutamide) before receiving abiraterone, while the remaining 66 received Abi directly. Therapeutic efficacy of Abi was compared between those with and without prior second-line NSAA using Kaplan-Meier curves, log-rank test, and Cox regression models. The therapeutic efficacy of Abi was similar between those with or without the prior switching treatment of flutamide, in terms of either prostate-specific antigen progression-free survival (PSA-PFS, 5.5 vs 5.6 months, P = 0.967), radiographic progression-free survival (rPFS, 12.8 vs 13.4 months, P = 0.508), overall survival (OS, not reached vs 30.6 months, P = 0.606), or PSA-response rate (71.4% [15/21] vs 60.6% [40/66], P = 0.370). This is the first time that the impact of prior switching of treatment to a second-line NSAA on the efficacy of Abi in mCRPC patients has been addressed. Our data support that, use of prior sequential bicalutamide and flutamide does not seem to preclude response to abiraterone, although larger cohort studies and, ideally, a randomized controlled trial are needed. These findings will facilitate doctors' decision-making in the treatment of mCRPC patients, especially for those with previous experience of switching NSAA second-line treatments in the clinic.

Commentary on: "Redirecting abiraterone metabolism to fine-tune prostate cancer anti-androgen therapy." Li Z, Alyamani M, Li J, Rogacki K, Abazeed M, Upadhyay SK, Balk SP, Taplin ME, Auchus RJ, Sharifi N. Nature. 2016 May 25;533(7604):547-51.

Abiraterone blocks androgen synthesis and prolongs survival in patients with castration-resistant prostate cancer, which is otherwise driven by intratumoral androgen synthesis. Abiraterone is metabolized in patients to Δ(4)-abiraterone (D4A), which has even greater antitumour activity and is structurally similar to endogenous steroidal 5α-reductase substrates, such as testosterone. Here, we show that D4A is converted to at least three 5α-reduced and three 5ß-reduced metabolites in human serum. The initial 5α-reduced metabolite, 3-keto-5α-abiraterone, is present at higher concentrations than D4A in patients with prostate cancer taking abiraterone, and is an androgen receptor agonist, which promotes prostate cancer progression. In a clinical trial of abiraterone alone, followed by abiraterone plus dutasteride (a 5α-reductase inhibitor), 3-keto-5α-abiraterone and downstream metabolites were depleted by the addition of dutasteride, while D4A concentrations rose, showing that dutasteride effectively blocks production of a tumor-promoting metabolite and permits D4A accumulation. Furthermore, dutasteride did not deplete the three 5ß-reduced metabolites, which were also clinically detectable, demonstrating the specific biochemical effects of pharmacological 5α-reductase inhibition on abiraterone metabolism. Our findings suggest a previously unappreciated and biochemically specific method of clinically fine-tuning abiraterone metabolism to optimize therapy.

Sponging off nature for new drug leads.

Marine sponges have consistently been the richest source of new marine natural products with unprecedented chemical scaffolds and potent biological activities that have been reported in the chemical literature since the early 1970s. During the last 40years, chemists in the Andersen laboratory at UBC, in collaboration with biologists, have discovered many novel bioactive sponge natural products. Four experimental drug candidates for treatment of inflammation and cancer, that were inspired by members of this sponge natural product collection, have progressed to phase I/II/III clinical trials. This review recounts the scientific stories behind the discovery and development of these four drug candidates; IPL576,092, HTI-286 (Taltobulin), EPI-506 (Ralaniten acetate), and AQX-1125.

1,4-Substituted Triazoles as Nonsteroidal Anti-Androgens for Prostate Cancer Treatment.

Prostate cancer (PC) is the fifth leading cause of cancer death in men, and the androgen receptor (AR) represents the primary target for PC treatment, even though the disease frequently progresses toward androgen-independent forms. Most of the commercially available nonsteroidal antiandrogens show a common scaffold consisting of two aromatic rings connected by a linear or a cyclic spacer. By taking advantage of a facile, one-pot click chemistry reaction, we report herein the preparation of a small library of novel 1,4-substituted triazoles with AR antagonistic activity. Biological and theoretical evaluation demonstrated that the introduction of the triazole core in the scaffold of nonsteroidal antiandrogens allowed the development of small molecules with improved overall AR-antagonist activity. In fact, compound 14d displayed promising in vitro antitumor activity toward three different prostate cancer cell lines and was able to induce 60% tumor growth inhibition of the CW22Rv1 in vivo xenograft model. These results represent a step toward the development of novel and improved AR antagonists.

Spironolactone and glucose metabolism, a systematic review and meta-analysis of randomized controlled trials.

Diabetes predicts cardiovascular disease (CVD); some drugs are effective for CVD prevention but increase the risk of diabetes. In a systematic review and meta-analysis of placebo-controlled trials, we assessed if spironolactone, a mineralocorticoid receptor antagonist, affected glycemic control. We searched PubMed using ("spironolactone" or "aldactone") and trial and ("glucose" or "diabetes" or "insulin" or "insulin resistance") until January 4, 2016. In total, 18 eligible trials were identified; 10 on fasting glucose, 8 on hemoglobin A1c (HbA1c), 7 on homeostatic model assessment (HOMA)-insulin resistance (IR), and 8 on insulin. Spironolactone increased HbA1c (0.16%, 95% confidence interval 0.02 to 0.30) but had no clear effect on fasting glucose, HOMA-IR, and insulin. A mechanistic randomized controlled trial in people with and without diabetes might provide insight concerning these pleiotropic effects on diabetes and CVD relevant to prevention of both diseases.

The World Federation of Societies of Biological Psychiatry (WFSBP) guidelines for the treatment of adolescent sexual offenders with paraphilic disorders.

The primary aim of these guidelines was to evaluate the role of pharmacological agents in the treatment of adolescents with paraphilic disorders who are also sexual offenders or at-risk of sexual offending. Psychotherapeutic and psychosocial treatments were also reviewed. Adolescents with paraphilic disorders specifically present a different therapeutic challenge as compared to adults. In part, the challenge relates to adolescents being in various stages of puberty and development, which may limit the use of certain pharmacological agents due to their potential side effects. In addition, most of the published treatment programmes have used cognitive behavioural interventions, family therapies and psychoeducational interventions. Psychological treatment is predicated in adolescents on the notion that sexually deviant behaviour can be controlled by the offender, and that more adaptive behaviours can be learned. The main purposes of these guidelines are to improve the quality of care and to aid physicians in their clinical decisions. These guidelines brought together different expert views and involved an extensive literature research. Each treatment recommendation was evaluated and discussed with respect to the strength of evidence for efficacy, safety, tolerability and feasibility. An algorithm is proposed for the treatment of paraphilic disorders in adolescent sexual offenders or those who are at risk.

The TMPRSS2:ERG fusion and response to androgen deprivation therapy for prostate cancer.

BACKGROUND: In the United States, half of men with prostate cancer harbor the androgen-regulated gene fusion TMPRSS2:ERG. We hypothesized that men with TMPRSS2:ERG positive tumors are more responsive to androgen deprivation therapy (ADT). METHODS: We studied a cohort of 239 men with prostate cancer from the Physicians' Health Study and Health Professionals Follow-up Study who received ADT during their disease course. Fusion status was assessed on available tumor tissue by immunohistochemistry for ERG protein expression. We used Cox models to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) for assessment of prostate cancer-specific mortality after ADT initiation. RESULTS: Roughly half of the men had stage T3 or higher tumors at diagnosis and 39% had Gleason 8-10 tumors. During an average follow up of 10.2 years, 42 men died from prostate cancer. There was a non-significant inverse association between positive fusion status and time to death from prostate cancer after ADT (multivariable HR: 0.76; 95% CI: 0.40-1.45). Harboring the TMPRSS2:ERG fusion was associated with a statistically significant lower risk of prostate cancer mortality among men who were treated with orchiectomy (multivariable HR: 0.13; 95% CI: 0.03-0.62), based on 15 events. CONCLUSIONS: Our results, combined with those from earlier studies, provide suggestive evidence that men with TMPRSS2:ERG positive tumors may have longer prostate cancer survival after ADT. Larger cohorts are needed for more robust results and to assess whether men with tumors harboring the fusion benefit from treatment with ADT in the (neo) adjuvant or metastatic setting specifically.

Development and validation of a prognostic index for fracture risk in older men undergoing prostate cancer treatment.

OBJECTIVES: Men treated with androgen deprivation therapy (ADT) or radiation therapy (RT) for prostate cancer have an increased risk for fractures. Given uncertainty as to whether specific clinical factors can identify men at increased risk, we sought to develop a prognostic index for risk of fracture in this population. MATERIALS AND METHODS: We used the Surveillance, Epidemiology, and End Results-Medicare database to identify men who received ADT or RT after being diagnosed with localized prostate cancer in 2007-2009. Cox proportional hazards models tested the association of potential risk factors with fracture. In a derivation group, hazard ratios were used to assign points for factors independently related to fracture. The prognostic index was then applied to a validation group. RESULTS: The sample of 5824 men had a median age of 73.0 years; 82.9% were white and 8.6% had a fracture within 2 years of treatment for prostate cancer. The Cox model identified 8 variables (age, race, hormone treatment, Elixhauser score, anxiety, Parkinson's, fall-inducing medications and disability status) independently associated with fracture. In the derivation cohort, 4.3% of the sample experienced a fracture in the low-risk group, 8.9% in the intermediate group, and 19.2% in the high-risk group (C statistic, 0.749). The index was applied to the validation cohort (C statistic, 0.782). CONCLUSION: The prognostic index can help to identify patients at increased risk for fracture. This underscores the importance of identifying risk factors for fracture, given the substantial variation in fracture risk in men treated with ADT or RT.

[Anti-androgen therapy for spinal and bulbar muscular atrophy (SBMA)].

Spinal and bulbar muscular atrophy (SBMA), or Kennedy's disease, is an adult-onset lower motor neuron disease caused by the expansion of a trinucleotide CAG repeat encoding a polyglutamine tract within the first exon of the androgen receptor (AR) gene. The testosterone-dependent nuclear accumulation of polyglutamine-expanded AR protein is central to the pathogenesis. This hypothesis is supported by pre-clinical studies showing that testosterone deprivation ameliorates motor neuron degeneration in animal modes of SBMA. In a randomized placebo-controlled multi-centric clinical trial, leuprorelin, which suppresses secretion of testosterone, showed no definite effect on motor functions, although there was the improvement of swallowing function in a subgroup of patients whose disease duration was less than 10 years. Elucidation of the entire disease mechanism, early initiation of therapeutic intervention, and sensitive outcome measures to evaluate drug effect appear to be the key to a successful translational research on SBMA.