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.

Guía de práctica clínica para el tratamiento del cáncer de próstata metastásico hormonosensible: guía en versión extensa / Clinical practice guideline for the treatment of metastatic hormone-sensitive prostate cancer: extended version guide

El cáncer de próstata metastásico se presenta en el 20% de pacientes al momento del diagnóstico de cáncer de próstata (1). Los sitios comunes de diseminación metastásica locorregional son los ganglios linfáticos (99%) y huesos como pelvis, cadera y esqueleto axial (84%); mientras que las localizaciones de metástasis a distancia más frecuentes son los ganglios linfáticos distantes (10.6%), y vísceras como hígado (10.2%) o pulmones (9.1%) (1). El cáncer de próstata metastásico es responsable de más de 400 000 muertes al año y se prevé que esta cifra se duplique al año 2040 (2). Además, características como la forma de presentación influyen en la supervivencia. Los pacientes con enfermedad metastásica al momento del debut de la enfermedad (de novo) suelen tener un tiempo de sobrevida más corto en comparación con los pacientes que desarrollan recidiva metastásica después del diagnóstico inicial de cáncer de próstata primario (recurrente) (1, 2). El pilar del tratamiento del cáncer de próstata metastásico es la terapia de deprivación androgénica (TDA), ya sea quirúrgica o farmacológica. La TDA tiene por finalidad reducir los niveles de testosterona sérica a niveles de castración para evitar el crecimiento tumoral (1, 3, 4). En este sentido, cuando el cáncer es susceptible a la TDA, se le denomina cáncer de próstata metastásico hormonosensible (CPMHS) (3, 4). Con el objetivo de mejorar la supervivencia de los pacientes con CPMHS, se han propuesto diferentes modalidades de administración de la TDA y el uso de terapias combinadas con TDA. Entre las terapias combinadas se describe la adición de quimioterápicos como docetaxel, el uso de radioterapia (RT), entre otras alternativas terapéuticas (3, 4). Actualmente, se ha propuesto la subclasificación de pacientes con CPMHS en base no solo a la presentación del cáncer (de novo o recurrente) sino también al volumen metastásico (alto o bajo) (4, 5). Esto es debido a que estos subgrupos tienen diferente pronóstico y las terapias pueden tener un balance, entre beneficios y daños, diferente para cada uno de ellos. Establecer las alternativas de tratamiento más eficaces y seguras para estos pacientes mejorará la supervivencia y calidad de vida de esta condición. Por ello, el Seguro Social de Salud (EsSalud) priorizó la realización de la presente guía de práctica clínica (GPC) para establecer lineamientos basados en evidencia con el fin de gestionar de la mejor manera los procesos y procedimientos asistenciales de la presente condición. Esta GPC fue realizada por la Dirección de Guías de Práctica Clínica, Farmacovigilancia y Tecnovigilancia del Instituto de Evaluación de Tecnologías en Salud e Investigación (IETSI) de EsSalud. Para ello, el grupo elaborador de la guía (GEG) tuvo en cuenta que para el manejo de estos pacientes se ha propuesto el uso de TDA en combinación con fármacos como enzalutamida, apalutamida, darolutamida, entre otros. Sin embargo, solo pudo ser posible evaluar las tecnologías sanitarias disponibles en el petitorio de EsSalud hasta enero de 2023 (TDA, docetaxel, y radioterapia).

Eficacia y seguridad de enzalutamida en pacientes adultos con cáncer de próstata resistente a la castración metastásico, con progresión a quimioterapia basada en docetaxel, y tienen contraindicaciones al uso, o desarrollan reacciones adversas que lleven a la interrupción de acetato de abiraterona / Efficacy and safety of enzalutamide in adult patients with metastatic castration-resistant prostate cancer, with progression to docetaxel-based chemotherapy, and have contraindications to use, or develop adverse reactions leading to discontinuation of abiraterone acetate

ANTECEDENTES En el marco de la metodología ad hoc para evaluar solicitudes de tecnologías sanitarias, aprobada mediante Resolución de Instituto de Evaluación de Tecnologías en Salud e Investigación N° 111-IETSI-ESSALUD-2021 y ampliada mediante Resolución de Instituto de Evaluación de Tecnologías en Salud e Investigación N° 97-IETSI-ESSALUD2022, se ha elaborado el presente dictamen, el cual expone la evaluación de la eficacia y seguridad de enzalutamida en pacientes adultos con cáncer de próstata resistente a la castración metastásico, con progresión a quimioterapia basada en docetaxel e intolerantes a acetato de abiraterona. Así, el Dr. Nelson Cuevas Muñoz, médico especialista en oncología del Hospital Nacional Edgardo Rebagliati Martins (HNERM), siguiendo la Directiva N° 003-IETSI-ESSALUD-2016, envió a través del comité farmacoterapéutico del Hospital HNERM al Instituto de Evaluación de Tecnologías en Salud e Investigación - IETSI la solicitud de autorización de uso del producto farmacéutico enzalutamida no incluido en el Petitorio Farmacológico de EsSalud. ASPECTOS GENERALES: El cáncer de próstata (CP) es el segundo cáncer más frecuente en hombres a nivel mundial y el más frecuente en Perú; registrándose 30.7 y 44.3 casos nuevos por cada 100 000 hombres en el 2020, respectivamente (GLOBOCAN [Internet] 2022). Asimismo, en el mismo año, se registró más de 375 000 muertes por CP en el mundo y 2433 muertes por CP en el Perú, representando así la segunda causa de muerte por cáncer en la población peruana (GLOBOCAN [Internet] 2022). El tratamiento sistémico de primera línea para el CP en estadios avanzados es la terapia de deprivación de andrógenos (Dawson y Leger 2022). Entre el 10 % y 27 % progresa a esta terapia, y el estado de la enfermedad se conoce como CP resistente a la castración (CPRC) (Bretoni, Ferrario, y Foglia 2019; Colloca et al. 2016). Aproximadamente, más del 70 % de pacientes con CPRC tienen CPRC metastásico (CPRCm) (Bretoni, Ferrario, y Foglia 2019). METODOLOGÍA: Se llevó a cabo una búsqueda bibliográfica exhaustiva con el objetivo de identificar la mejor evidencia sobre la eficacia y seguridad de enzalutamida en pacientes adultos con CPRCm, con progresión a quimioterapia basada en docetaxel e intolerantes a AA. La búsqueda bibliográfica se realizó en las bases de datos PubMed, The Cochrane Library, Web of Science y LILACS. Asimismo, se realizó una búsqueda manual dentro de las páginas web pertenecientes a grupos que realizan evaluación de tecnologías sanitarias (ETS) y guías de práctica clínica (GPC) incluyendo el National Institute for Health and Care Excellence (NICE), la Canadian Agency for Drugs and Technologies in Health (CADTH), el Scottish Medicines Consortium (SMC), el Scottish Intercollegiate Guidelines Network (SIGN). el Institute for Quality and Efficiency in Healthcare (IQWiG por sus siglas en alemán), la International Database of GRADE Guideline, el Centro Nacional de Excelencia Tecnológica en Salud (CENETEC), la Guidelines International Network (GIN), el National Health and Medical Research Council (NHMRC), la Cancer Guidelines Database, el New Zealand Guidelines Group (NZGG), el Instituto de Evaluación Tecnológica en Salud (IETS), el Instituto de Efectividad Clínica y Sanitaria (IECS), la Base Regional de Informes de Evaluación de Tecnologías en Salud de las Américas (BRISA), la Organización Mundial de la Salud, el Ministerio de Salud del Perú (MINSA) y el Instituto de Evaluación de Tecnologías en Salud e Investigación (IETSI). Además, se realizó una búsqueda de GPC de las principales sociedades o instituciones especializadas en oncología o urología, tales como: National Comprehensive Cancer Network (NCCN), la Cancer Council Australia (CCA), la European Society for Medical Oncology (ESMO), la American Society of Clinical Oncology (ASCO), la Sociedad Española de Oncología Médica (SEOM), la European Association of Urology (EAU) y la American Urological Association (AUA). Finalmente, se realizó una búsqueda en la página web de registro de ensayos clínicos (EC) www.clinicaltrials.gov, para identificar EC en curso o que no hayan sido publicados aún. RESULTADOS: Luego de la búsqueda bibliográfica hasta mayo de 2023, se identificaron cinco GPC elaboradas por la NCCN (NCCN 2022), la ESMO (Parker et al. 2020), la EAU (EAU 2022a), la SEOM (González del Alba et al. 2021) y la ASCO (Basch et al. 2014), y un ECA denominados AFFIRM (Scher et al. 2012). CONCLUSIÓN: Por lo expuesto, el Instituto de Evaluación de Tecnologías en Salud e Investigación aprueba el uso de enzalutamida para pacientes adultos con CPRCm, con progresión a quimioterapia basada en docetaxel, con contraindicaciones al uso, o desarrollo de reacciones adversas que lleven a la interrupción, de AA, como producto farmacéutico no incluido en el Petitorio Farmacológico de EsSalud, según lo establecido en el Anexo N° 1. La vigencia del presente dictamen preliminar es de un año a partir de la fecha de publicación. Así, la continuación de dicha aprobación estará sujeta a la evaluación de los resultados obtenidos y de mayor evidencia que pueda surgir en el tiempo.

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.

Abiraterone acetate versus nonsteroidal antiandrogen with androgen deprivation therapy for high-risk metastatic hormone-sensitive prostate cancer.

BACKGROUND: Although prostate cancer is a very common form of malignancy in men, the clinical significance of androgen deprivation therapy (ADT) with abiraterone acetate versus the nonsteroidal antiandrogen bicalutamide has not yet been verified in patients with high-risk metastatic hormone-sensitive prostate cancer (mHSPC). The present study was designed to initiate this verification in real-world Japanese clinical practice. METHODS: We retrospectively analyzed the records of 312 patients with high-risk mHSPC based on LATITUDE criteria and had received ADT with bicalutamide (n = 212) or abiraterone acetate (n = 100) between September 2015 and December 2020. Bicalutamide was given at 80 mg daily and abiraterone was given at 1000 mg daily as four 250-mg tablets plus prednisolone (5-10 mg daily). Overall survival (OS), cancer-specific survival (CSS), and time to castration-resistant prostate cancer (CRPC) were compared. The prognostic factor for time to CRPC was analyzed by Cox proportional hazard model. RESULTS: Patients in the bicalutamide group were older, and more of them had poor performance status (≧2), than in the abiraterone group. Impaired liver function was noted in 2% of the bicalutamide group and 16% of the abiraterone group (p < 0.001). Median follow-up was 22.5 months for bicalutamide and 17 months for abiraterone (p < 0.001). Two-year OS and CSS for bicalutamide versus abiraterone was 77.8% versus 79.5% (p = 0.793) and 81.1% versus 82.5% (p = 0.698), respectively. Median time to CRPC was significantly longer in the abiraterone group than in the bicalutamide group (NA vs. 13 months, p < 0.001). In multivariate analysis, Gleason score ≧9, high alkaline phosphatase, high lactate dehydrogenase, liver metastasis, and bicalutamide were independent prognostic risk factors for time to CRPC. Abiraterone prolonged the time to CRPC in patients with each of these prognostic factors. CONCLUSIONS: Despite limitations regarding the time-dependent bias, ADT with abiraterone acetate significantly prolonged the time to CRPC compared to bicalutamide in patients with high-risk mHSPC. However, further study with longer follow-up is needed.

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.

Tratamiento del cáncer de próstata resistente a la castración y riesgo de interacciones farmacológicas en pacientes polimedicados / Treatment for castration-resistant prostate cancer and drug interaction risk in polymedicated patients

No disponible

Development of Androgen-Antagonistic Coumarinamides with a Unique Aromatic Folded Pharmacophore.

First-generation nonsteroidal androgen receptor (AR) antagonists, such as flutamide (2a) and bicalutamide (3), are effective for most prostate cancer patients, but resistance often appears after several years due to the mutation of AR. Second-generation AR antagonists are effective against some of these castration-resistant prostate cancers, but their structural variety is still limited. In this study, we designed and synthesized 4-methyl-7-(N-alkyl-arylcarboxamido)coumarins as AR antagonist candidates and evaluated their growth-inhibitory activity toward androgen-dependent SC-3 cells. Coumarinamides with a secondary amide bond did not show inhibitory activity, but their N-methylated derivatives exhibited AR-antagonistic activity. Especially, 19b and 31b were more potent than the lead compound 7b, which was comparable to hydroxyflutamide (2b). Conformational analysis showed that the inactive coumarinamides with a secondary amide bond have an extended structure with a trans-amide bond, while the active N-methylated coumarinamides have a folded structure with a cis-amide bond, in which the two aromatic rings are placed face-to-face. Docking study suggested that this folded structure is important for binding to AR. Selected coumarinamide derivatives showed AR-antagonistic activity toward LNCaP cells with T877A AR, and they had weak progesterone receptor (PR)-antagonistic activity. The folded coumarinamide structure appears to be a unique pharmacophore, different from those of conventional AR antagonists.

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.

Review of HPLC and LC-MS/MS assays for the determination of various nonsteroidal anti-androgens used in the treatment of prostate cancer.

Prostate cancer is the most common cancer and one of the leading causes of cancer deaths in men. One of the commonly used approaches to treat metastatic prostate cancer was via first-generation nonsteroidal anti-androgens (NSAAs), namely flutamide, nilutamide, bicalutamide and topilutamide. Most prostate cancer patients who are initially responsive develop the most aggressive form of disease called castration-resistant prostate cancer. Second-generation NSAA receptor antagonists (enzalutamide, apalutamide and darolutamide) are emerging as additional new options to treat castration-resistant prostate cancer. The objective of this work was to review the literature on the bioanalytical methods for the quantification of first- and second-generation NSAA inhibitors in clinical (human plasma) and preclinical (mouse plasma, rat plasma, urine and tissue homogenates etc.) studies along with relevant case studies for some chosen drugs. Based on the review, it was concluded that the published methodologies using either HPLC or LC-MS/MS are well suited for the quantification of NSAA inhibitors in various biological fluids to delineate pharmacokinetic data.

Informe de evaluación científica en la evidencia disponible: cáncer de próstata / Scientific evaluation report on the available evidence: prostate cancer

INTRODUCCIÓN: Este informe evalúa abiraterona y enzalutamida para pacientes con CP metastásico resistente a castración en segunda línea de tratamiento. Esta condición de salud cuenta con cobertura GES hasta el tratamiento de primera línea de este subgrupo de pacientes. Se considerarán para su evaluación aquellas solicitudes realizadas conforme al Reglamento que establece el proceso destinado a determinar los diagnósticos y tratamientos de alto costo con sistema de protección financiera, según lo establecido en los artículos 7° y 8° de la Ley N° 20.850. Estas solicitudes no son vinculantes para el Ministerio de Salud, debiendo, sin embargo, tomar especialmente en cuenta aquellas solicitudes y opiniones que hayan sido realizadas por sus comisiones técnicas asesoras y por las asociaciones de pacientes incluidas en el Registro de Asociaciones de Pacientes que crea la Ley 20.850. El Cáncer de Próstata (CP) es uno de los tumores sólidos más frecuentes en hombres en el mundo, que frecuentemente no evolucionan a cánceres agresivos, y que además son detectados a través del tamizaje de antígeno prostático. Una fracción de estos cánceres progresa con metástasis, reduciendo bruscamente su sobrevida. El CP se observa mayoritariamente en hombres mayores de 60 años, y su incidencia en Chile es de 52,4 por 100.000, siendo además la segunda causa de muerte por cáncer en hombres. TECNOLOGÍAS SANITARIA DE INTERÉS: : Abiraterona: El acetato de abiraterona es un Inhibidor de la biosíntesis de andrógenos (hormonas masculinas). Enzalutamida: Es un potente inhibidor de la señalización del receptor de andrógenos que bloquea varios pasos en la vía de señalización del receptor de andrógenos sobreexpresado en el cáncer de próstata. EFICACIA DE LOS TRATAMIENTOS: Abiraterona: Para evaluar su efecto se comparó con 2 alternativas de tratamiento: Placebo: Se identificó 2 ensayos controlados aleatorizados que evaluaban los efectos de abiraterona en comparación a placebo en personas con cáncer de próstata avanzado, resistente a castración y con quimioterapia previa. De acuerdo a esta evidencia usar abiraterona comprado con placebo disminuye la mortalidad, pero probablemente aumenta los efectos adversos serios. Bicalutamida: No se identificó evidencia directa que evaluaba el efecto de abiraterona en comparación a bicalutamida en personas con cáncer de próstata avanzado, resistente a castración y con quimioterapia previa, por lo que se recurrió a comparaciones indirectas, seleccionándose una revisión sistemática que utilizó la técnica metaanálisis en red para comparar ambos fármacos como tratamiento de primera línea. De acuerdo a esta evidencia tratar con abiraterona comparado con tratar bicalutamida podría ser más efectiva en prolongar la sobrevida libre de enfermedad, sin embargo podría tener más efectos adversos severos. No se pudo estimar el efecto sobre la mortalidad, dado que no se reportaron los datos. Enzalutamida: Para evaluar su efecto se comparó con 2 alternativas de tratamiento: Placebo: Se identificó 1 ensayo controlado aleatorizado que evaluaba los efectos de enzalutamida en comparación a placebo en personas con cáncer de próstata avanzado, resistente a castración y con quimioterapia previa. De acuerdo a esta evidencia se observó que usar enzalutamida disminuye la mortalidad, pero probablemente aumenta los efectos adversos serios. Bicalutamida: No se identificó evidencia directa que evaluaba el efecto de enzalutamida en comparación a bicalutamida en personas con cáncer de próstata avanzado, resistente a castración y con quimioterapia previa, por lo que se recurrió a comparaciones indirectas, seleccionándose 2 ensayos controlados aleatorizados que comparaban ambos fármacos como tratamiento de primera línea (sin quimioterapia previa). De acuerdo a esta evidencian no está claro si existen diferencias entre enzalutamida y bicalutamida en relación a la mortalidad, por otro lado enzalutamida podría tener más efectos adversos que bicalutamida. ALTERNATIVAS DISPONIBLES: En pacientes con CPMRC que ya han recibido un régimen de quimioterapia basado en docetaxel de manera previa, la alternativa terapéutica a la abiraterona y la enzalutamida sería cabazitaxel, aunque éste no ha sido solicitado para su cobertura. De manera adicional, la mitoxantrona es también una alternativa para estos pacientes, aunque su uso es infrecuente en la práctica clínica, dado que es una tecnología muy antigua, y no cuenta con indicación para CP en Chile. Sin embargo, cabazitaxel demostró su eficacia comparativa para esta población al compararse con mitoxantrona en esta población (13). En el caso de abiraterona y enzalutamida, los comparadores utilizados en los estudios clínicos para demostrar eficacia fueron placebo en ambos casos, publicados en 2011 y 2012, respectivamente. En los casos donde existan metástasis óseas, se puede también considerar el uso de radioterapia (Radium 223) para aliviar los dolores asociados a estos sitios de metástasis, lo cual comúnmente se adiciona a alguna de las terapias anti andrógenas. Actualmente, la cobertura GES incluye el tratamiento con docetaxel para pacientes con CPMRC, pero no se incorpora la cobertura de los pacientes que su enfermedad ha progresado después de éste. La canasta específica del CPMRC incorpora bicalutamida y flutamida, pero existen dudas sobre el uso de estos tratamientos en pacientes que han progresado después de quimioterapia. CONCLUSIÓN: Para dar cumplimiento al artículo 28° del Reglamento que establece el proceso destinado a determinar los diagnósticos y tratamientos de alto costo con Sistema de Protección Financiera, según lo establecido en los artículos 7°y 8° de la ley N°20.850, aprobado por el decreto N°13 del Ministerio de Salud, se concluye que el presente informe de evaluación se considera favorable para abiraterona, de acuerdo a lo establecido en el Título III. de las Evaluaciones Favorables de la Norma Técnica N° 0192 de este mismo ministerio. Para dar cumplimiento al artículo 28° del Reglamento que establece el proceso destinado a determinar los diagnósticos y tratamientos de alto costo con Sistema de Protección Financiera, según lo establecido en los artículos 7°y 8° de la ley N°20.850, aprobado por el decreto N°13 del Ministerio de Salud, se concluye que el presente informe de evaluación se considera favorable para enzalutamida, de acuerdo a lo establecido en el Título III. de las Evaluaciones Favorables de la Norma Técnica N° 0192 de este mismo ministerio.

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 / 亚洲男科学杂志(英文版)

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.

Investigations on the dose-response relationship of combined exposure to low doses of three anti-androgens in Wistar rats.

The current investigation examines whether combined exposure to three anti-androgens (flutamide, prochloraz, vinclozolin) result in interference with endocrine homeostasis when applied at very low dose levels, and whether the results of combined exposure are more pronounced than to the individual compounds. A pre-post-natal in vivo study design was chosen with more parameters than regulatory testing protocols require (additional endpoints addressing hormone levels, morphology and histopathological examinations). Dose levels were chosen to represent the lowest observed adverse effect level (LOAEL), the no observed adverse effect level (NOAEL), and the acceptable daily intake for each individual substance. Anti-androgenic changes were observable at the effect level (LOAEL) but not at lower exposures. Nipple/areola counts appeared to be a sensitive measure of effect, in addition to male sex organ weights at sexual maturation, and finally gross findings. The results indicate the absence of evidence for effects at low or very low dose levels. No (adverse) effects were seen at the NOAEL dose. A non-monotonic dose-response relationship was not evident. Combined exposure at LOAEL level resulted in enhanced responses for anogenital index, number of areolas/nipples, delayed preputial separation and reduced ventral prostate weight in comparison to the individual compounds.

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.

Parallel assessment of the effects of bisphenol A and several of its analogs on the adult human testis.

STUDY QUESTION: Are bisphenol A (BPA) and BPA analogs (BPA-A) safe for male human reproductive function? SUMMARY ANSWER: The endocrine function of human testes explants [assessed by measuring testosterone and insulin-like factor 3 (INSL3)] was impacted by exposure of the human adult testis explants to BPA/BPA-A. WHAT IS KNOWN ALREADY: The few epidemiologic studies performed suggest that bisphenols have potential endocrine disruptive properties, but they did not identify clear and direct patterns of endocrine disruption. STUDY DESIGN, SIZE, DURATION: Adult human testis explants in culture were exposed to BPA and the analogs bisphenol F (BPF), bisphenol S (BPS), bisphenol E (BPE), bisphenol B (BPB) and bisphenol A diglycidyl ether (BADGE) at 10-9-10-5 M for 24 or 48 h. PARTICIPANTS/MATERIALS, SETTING, METHODS: Human adult testes were obtained from prostate cancer patients who had no hormone therapy, or from multiorgan donors. After ex vivo exposure to the investigated bisphenols, the measured outcomes were related to histopathology (gross morphology and germ cell viability determined by anti-caspase three immunohistochemistry), and the levels of testosterone, INSL3 and inhibin B were measured using immunoassays. The levels of mRNA encoding key enzymes of bisphenol biotransformation were investigated by quantitative PCR: UGT2B15 UDP (glucuronosyltransferase two family, polypeptide B15), GUSB (glucuronidase beta), SULT1A1 and 3 (sulfotransferase family 1 A member 1 and 3) and STS (steroid sulfatase). MAIN RESULTS AND THE ROLE OF CHANCE: A significant dose-dependent inhibition was found between testosterone levels measured in the culture medium and concentrations of BPA (P = 0.00778 at 24 h and P = 0.0291 at 48 h), BPE (P = 0.039) and BPF (P = 0.00663). The observed BPA and BPA-A-induced inhibition of testosterone production varied according to duration of exposure and BPA/BPA-A concentrations. BPA (10-9 M; P < 0.05), BPB (10-9 M; P < 0.05), BPS (10-9 and 10-8 M; P < 0.05) and BADGE (10-5 M; P < 0.05) increased Leydig cell INSL3 production. By contrast, BPE dose dependently inhibited INSL3 (P = 0.0372). Conversely, Sertoli cell function (inhibin B) and germ cell viability were not significantly affected by either bisphenols. LARGE SCALE DATA: N/A. LIMITATIONS, REASONS FOR CAUTION: Environmental compounds cannot be deliberately administered to men, justifying the use of an ex vivo approach. A relatively low number of testes samples were available for analysis (n = 3, except for testosterone secretion with n = 5). The active concentrations of BPA and BPA-A used in the study were higher than those found in human biological fluids. WIDER IMPLICATIONS OF THE FINDINGS: Under our experimental conditions, direct exposure to BPA or BPA-A can result in endocrine disturbance in the adult human testis. STUDY FUNDING/COMPETING INTEREST(S): This study was funded by Inserm (Institut National de la Santé et de la Recherche Médicale), EHESP-School of Public Health, University of Rennes1, by grants from the Agence Nationale de la Recherche (ANR; grant#ANR-13-CESA-0012-03 NEWPLAST) and Agence Nationale de Sécurité Sanitaire de l'Alimentation, de l'Environnement et du Travail (ANSES; grant#EST-2010/2/046 (BPATESTIS)). All authors declare they have no current or potential competing financial interests.

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.