A First-in-Human Phase 1 Study of a Novel Selective Androgen Receptor Modulator (SARM), RAD140, in ER+/HER2- Metastatic Breast Cancer

Athlete Selective Androgen Receptor Modulators Abuse: A Systematic Review

BACKGROUND

Selective androgen receptor modulators (SARMs) are small-molecule compounds that exert agonist and antagonist effects on androgen receptors in a tissue-specific fashion. Because of their performance-enhancing implications, SARMs are increasingly abused by athletes. To date, SARMs have no Food and Drug Administration approved use, and recent case reports associate the use of SARMs with deleterious effects such as drug-induced liver injury, myocarditis, and tendon rupture.

PURPOSE

(1) To provide a comprehensive synthesis of the literature pertaining to SARMs from a sports medicine perspective and (2) to provide a better understanding of the clinical effects, treatment protocols, prevalence, and potential contamination associated with athlete-consumed SARMs.

STUDY DESIGN

Systematic review; Level of evidence, 4.

METHODS

A systematic review of the English-language literature from PubMed, Cochrane, and Embase databases was performed according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Articles relevant to SARM clinical outcomes, elimination profiles, contamination, safety profiles, prevalence, and doping control were included.

RESULTS

A total of 72 articles from 2003 to 2022 were identified for inclusion. The prevalence of SARM use among athletes is estimated to be 1% to 3%. SARM preclinical and clinical studies reported significant increases in lean body mass and side effects-including bone remodeling, testosterone suppression, and kidney, liver, and prostate enlargement. Thirteen case reports described 15 cases of SARM abuse. All described patients were men, with a median age of 32 years (range, 19-52 years), more than half were identified as athletes (8/15), and all ingested SARMs orally for a mean course of 8 weeks. Five patients described in the case reports explicitly denied "illicit drug use," implying patients may believe their use to be legal. Athletes most commonly purchased SARMs online, and most of these compounds have been shown to be contaminated with other substances, contributing to adverse effects. Athletes reported consuming SARMs at much higher doses than clinically studied, which may increase the risk of the reported side effects, such as liver injury, impaired insulin sensitivity, cardiovascular events, and tendon damage.

CONCLUSION

The results of this systematic review serve to educate sports medicine clinicians and researchers on how to better identify, diagnose, and treat athlete SARM abuse. SARM use is associated with increased muscle mass, hepatotoxicity, cardiotoxicity, tendon damage, and androgenic side effects throughout the body-including prostate enlargement and serum testosterone suppression. Identifying and treating SARM abuse requires taking a thorough substance and supplement use history with open communication, providing literature-supported patient education, negotiating SARM discontinuation, and performing multidisciplinary treatment of adverse events. Athlete SARM abuse is increasingly widespread and unsafe, and public health oversight bodies should advocate for regulation of these gray-market compounds.

Myopericarditis Following Use of Selective Androgen Receptor Modifier "RAD-140"

We report the case of a 16-year-old boy who had myopericarditis following the first dose of a selective androgen receptor modulator called Testolone ("RAD-140"). These drugs are widely abused by physically active young adults; however, the drugs' side effects, which can be life-threatening, are not well characterized.

Reversible Gynecomastia and Hypogonadism Due to Usage of Commercial Performance-Enhancing Supplement Use

Commercially available performance-enhancing supplements can contain banned performance-enhancing drugs (PEDs) and undisclosed steroid hormones that can induce hormonal abnormalities with associated clinical signs. We present a case of a 40-year-old male who developed bilateral gynecomastia and biochemical hypogonadotropic hypogonadism with a corresponding 6-month history of consuming commercially available performance-enhancing supplements for gym workouts. These performance-enhancing supplements were found to contain amounts of RAD-140, a selective androgen receptor modulator, MK-677, a GH secretagogue and cardarine, all of which are banned PEDs. In vitro analysis also detected undisclosed hormones testosterone, estradiol, and GH in all 3 supplements, with further steroid analysis using liquid chromatography mass spectrometry identifying an unidentified compound coeluting close to the testosterone peak. Cessation of these supplements led to full resolution of symptoms including normalization of hypogonadotropic hypogonadism. This case highlights the need for clinicians to consider commercially available performance-enhancing supplements as potential sources of PEDs and exogenous steroid hormones that can have adverse clinical consequences.

Advances in SARMs anti-doping analysis

Selective androgen receptor modulators (SARMs) are performance-enhancing drugs (PEDs) that stimulate anabolism, increase muscle mass and strength and promote recovery from exercise. The use of SARMs in sports is considered doping and is strictly prohibited by the World Anti-Doping Agency (WADA) and the International Federation of Horseracing Authorities (IFHA). To monitor the abuse of SARMs in sports, it is essential to develop advanced, selective and sensitive analytical methods that provide reliable results. This review evaluates the advances in this area, with a focus on the identification of target analytes related to SARMs, such as SARMs, their metabolites or markers. The aim is to identify targets that could extend the detection windows of SARMs, provide scientific support for results management and/or offer an indirect biomarker-based approach to doping control. This review also aims to evaluate the current liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) methods developed for the monitoring of SARMs in different biological matrices, including traditional matrices such as urine and serum/plasma samples, as well as alternative matrices such as dried blood spots, hair and nail samples.

Activity and safety of enobosarm, a novel, oral, selective androgen receptor modulator, in androgen receptor-positive, oestrogen receptor-positive, and HER2-negative advanced breast cancer (Study G200802): a randomised, open-label, multicentre, multinational, parallel design, phase 2 trial

BACKGROUND

The androgen receptor is a tumour suppressor in oestrogen receptor-positive breast cancer. The activity and safety of enobosarm, an oral selective androgen receptor modulator, was evaluated in women with oestrogen receptor (ER)-positive, HER2-negative, and androgen receptor (AR)-positive disease.

METHODS

Women who were postmenopausal (aged ≥18 years) with previously treated ER-positive, HER2-negative, locally advanced or metastatic breast cancer with an Eastern Cooperative Oncology Group performance status of 0-2 were enrolled in a randomised, open-label, multicentre, multinational, parallel design, phase 2 trial done at 35 cancer treatment centres in nine countries. Participants were stratified on the setting of immediately preceding endocrine therapy and the presence of bone-only metastasis and randomly assigned (1:1) to 9 mg or 18 mg oral enobosarm daily using an interactive web response system. The primary endpoint was clinical benefit rate at 24 weeks in those with centrally confirmed AR-positive disease (ie, the evaluable population). This trial is registered with ClinicalTrials.gov (NCT02463032).

FINDINGS

Between Sept 10, 2015, and Nov 28, 2017, 136 (79%) of 172 patients deemed eligible were randomly assigned to 9 mg (n=72) or 18 mg (n=64) oral enobosarm daily. Of these 136 patients, 102 (75%) patients formed the evaluable population (9 mg, n=50; 18 mg, n=52). The median age was 60·5 years (IQR 52·3-69·3) in the 9 mg group and 62·5 years (54·0-69·3) in the 18 mg group. The median follow-up was 7·5 months (IQR 2·9-14·1). At 24 weeks, 16 (32%, 95% CI 20-47) of 50 in the 9 mg group and 15 (29%, 17-43) of 52 in the 18 mg group had clinical benefit. Six (8%) of 75 patients who received 9 mg and ten (16%) of 61 patients who received 18 mg had grade 3 or grade 4 drug-related adverse events, most frequently increased hepatic transaminases (three [4%] of 75 in the 9 mg group and two [3%] of 61 in the 18 mg group), hypercalcaemia (two [3%] and two [3%]), and fatigue (one [1%] and two [3%]). Four deaths (one in the 9 mg group and three in the 18 mg group) were deemed unrelated to the study drug.

INTERPRETATION

Enobosarm has anti-tumour activity in patients with ER-positive, HER2-negative advanced breast cancer, showing that AR activation can result in clinical benefit, supporting further clinical investigation of selective AR activation strategies for the treatment of AR-positive, ER-positive, HER2-negative advanced breast cancer.

FUNDING

GTx.

Treatments Targeting the Androgen Receptor and Its Splice Variants in Breast Cancer

Breast cancer is a major cause of death worldwide. The complexity of endocrine regulation in breast cancer may allow the cancer cells to escape from a particular treatment and result in resistant and aggressive disease. These breast cancers usually have fewer treatment options. Targeted therapies for cancer patients may offer fewer adverse side effects because of specificity compared to conventional chemotherapy. Signaling pathways of nuclear receptors, such as the estrogen receptor (ER), have been intensively studied and used as therapeutic targets. Recently, the role of the androgen receptor (AR) in breast cancer is gaining greater attention as a therapeutic target and as a prognostic biomarker. The expression of constitutively active truncated AR splice variants in breast cancer is a possible mechanism contributing to treatment resistance. Therefore, targeting both the full-length AR and AR variants, either through the activation or suppression of AR function, depending on the status of the ER, progesterone receptor, or human epidermal growth factor receptor 2, may provide additional treatment options. Studies targeting AR in combination with other treatment strategies are ongoing in clinical trials. The determination of the status of nuclear receptors to classify and identify patient subgroups will facilitate optimized and targeted combination therapies.

Selective androgen receptor modulator use and related adverse events including drug-induced liver injury: Analysis of suspected cases

PURPOSE

Selective androgen receptor modulators (SARMs) have demonstrated agonist activity on the androgen receptor in various tissues, stimulating muscle mass growth and improving bone reconstruction. Despite being in clinical trials, none has been approved by the Food and Drug Administration (FDA) or European Medicines Agency for pharmacotherapy. Still, SARMs are very popular as performance-enhancing drugs. The FDA has issued warnings about the health risks associated with SARMs, but the long-term exposure and possible adverse events still need to be fully understood. This review aims to evaluate the adverse events associated with using SARMs by humans.

METHODS

PubMed database was searched from September 16, 2022, to October 2, 2023. In total, 20 records were included in the final review. Data from preclinical and clinical studies supported the review.

RESULTS

Since 2020, 20 reports of adverse events, most described as drug-induced liver injury associated with the use of SARM agonists, have been published. The main symptoms mentioned were cholestatic or hepatocellular liver injury and jaundice. Limited data are related to the dosages and purity of SARM supplements.

CONCLUSION

Promoting SARMs as an anabolic agent in combination with other performance-enhancing drugs poses a risk to users not only due to doping controls but also to health safety. The lack of quality control of consumed supplements makes it very difficult to assess the direct impact of SARMs on the liver and their potential hepatotoxic effects. Therefore, more detailed analyses are needed to determine the safety of using SARMs.

Comparison of in vitro approaches for predicting the metabolism of the selective androgen receptor modulator RAD140

The identification of metabolites allows for the expansion of possible targets for anti-doping analysis. Especially for novel substances such as selective androgen receptor modulators (SARMs), information on metabolic fate is scarce. Novel approaches such as the organ on a chip technology may provide a metabolic profile that resembles human in vivo samples more closely than approaches that rely on human liver fractions only. In this study, the SARM RAD140 was metabolized by means of subcellular human liver fractions, human liver spheroids in an organ on a chip platform, and electrochemical (EC) conversion. The resulting metabolites were analyzed with LC-HRMS/MS and compared to a human doping control urine sample that yielded an adverse analytical finding for RAD140. A total of 16 metabolites were detected in urine, while 14, 13, and 7 metabolites were detected in samples obtained from the organ on a chip experiment, the subcellular liver fraction, and EC experiments, respectively. All tested techniques resulted in the detection of RAD140 metabolites. In the organ on a chip samples, the highest number of metabolites were detected. The subcellular liver fractions and organ on a chip techniques are deemed complementary to predict metabolites of RAD140, as both techniques produce distinct metabolites that are also found in an anonymized human in vivo urine sample.

Androgen Receptor and Cardiovascular Disease: A Potential Risk for the Abuse of Supplements Containing Selective Androgen Receptor Modulators

The androgen receptor (AR) is a member of the family of ligand-activated transcription factors. Selective androgen receptor modulators (SARMs) exert their biological function through complex interactions with the AR. It has been speculated that overexertion of AR signaling cascades as a result of SARM abuse can be a risk factor for the development of various cardiovascular diseases. The present literature review explores the implications of the interaction between SARMs and the AR on cardiovascular health by focusing on the AR structure, function, and mechanisms of action, as well as the current clinical literature on various SARMs. It is shown that SARMs may increase the risk of cardiovascular diseases through implications on the renin-angiotensin system, smooth muscle cells, sympathetic nervous system, lipid profile, inflammation, platelet activity, and various other factors. More research on this topic is necessary as SARM abuse is becoming increasingly common. There is a noticeable lack of clinical trials and literature on the relationship between SARMs, cardiovascular diseases, and the AR. Future in vivo and in vitro studies within this field are vital to understand the mechanisms that underpin these complex interactions and risk factors.

Social media may cause emergent SARMs abuse by athletes: a content quality analysis of the most popular YouTube videos

OBJECTIVES

Selective Androgen Receptor Modulators (SARMs) social media interest is at an all-time high. The aim of this study is to analyze the: (1) quality; (2) educational content; and (3) reliability of the most relevant YouTube videos on SARMs to explain growing SARMs abuse by recreational and professional athletes.

METHODS

'SARMs' was queried (28 November 2021) through the YouTube video library. The top 100 videos filtered by relevance were categorized by source, type of content, educational quality by Global Quality Score (GQS), reliability by Journal of American Medicine Association (JAMA) criteria, YouTube tags, attitude toward SARMs use, and whether the video provided specific support on how to use SARMs. For all outcome variables, descriptive statistics and comparison among source types and category types were performed.

RESULTS

Mean JAMA score was 1.6 ± 0.7 out of 4. Mean GQS score was 2.5 ± 1.1 out of 5. Patient videos were of lower educational quality than athletic trainer videos (GQS: 2.11 ± 0.95 vs. 2.95 ± 1.00, p < 0.01), and videos categorized as user experience were of lower educational quality than videos categorized as general SARMs information (GQS: 1.92 ± 0.90 vs. 2.72 ± 1.07, p < 0.05). User experience and dosing recommendation videos were statistically significantly more positive in attitude than both general SARMs information and SARMS vs. other PEDs.

CONCLUSION

Quality, content, and reliability of SARMs YouTube videos was low. Social media likely causes SARMs abuse through disseminating biased SARMs misinformation. These results serve to educate public health oversight bodies, healthcare providers, and sports team members to better identify signs of SARMs abuse, and promote discussion to discourage SARMs abuse.

Idiosyncratic drug-induced liver injury related to use of novel selective androgen receptor modulator RAD140 (Testalone): a case report

BACKGROUND

RAD140 (Testalone) is a novel selective androgen receptor modulator with very limited data currently available on adverse effects related to this compound. The first-in-human phase 1 trial was recently published and did report a significant proportion of elevated aspartate aminotransferase, alanine transaminase, and total bilirubin among the test subjects. RAD140 may be associated with an idiosyncratic drug-induced liver injury. It is easily purchased online as a workout supplement. Given its ease of use from being an oral formulation, and not requiring a physician's prescription, its use among the young male population will likely rise. Clinicians should ask about the use of RAD140, and other workout supplements, in young men presenting with acute liver injury.

CASE PRESENTATION

We present the case of a 26-year-old Caucasian male without any significant past medical history who presented with nausea, vomiting, severe right upper quadrant abdominal pain, and jaundice from acute liver injury. Extensive inpatient workup did not reveal a definite cause for his liver injury other than the use of a novel selective androgen receptor modulator called RAD140 (Testalone). He was treated with supportive care and discharged after short hospitalization. He was instructed to stop RAD140, which he reported compliance with, and on 2-month follow-up his liver function panel had normalized without recurrence of any symptoms.

CONCLUSION

Novel selective androgen receptor modulators such as RAD140 may be associated with idiosyncratic drug-induced liver injury. Workup of new liver injury in young and middle-aged males should involve asking about use of these novel compounds, for if missed and use continues, it can likely lead to fulminant liver failure or decompensated liver cirrhosis.

Newly Developed Targeted Therapies Against the Androgen Receptor in Triple-Negative Breast Cancer: A Review

Among different types of breast cancers (BC), triple-negative BC (TNBC) amounts to 15% to 20% of breast malignancies. Three principal characteristics of TNBC cells are (i) extreme aggressiveness, (ii) absence of hormones, and (iii) growth factor receptors. Due to the lack or poor expression of the estrogen receptor, human epidermal growth factor receptor 2, and progesterone receptor, TNBC is resistant to hormones and endocrine therapies. Consequently, chemotherapy is currently used as the primary approach against TNBC. Expression of androgen receptor (AR) in carcinoma cells has been observed in a subset of patients with TNBC; therefore, inhibiting androgen signaling pathways holds promise for TNBC targeting. The new AR inhibitors have opened up new therapy possibilities for BC patients carrying AR-positive TNBC cells. Our group provides a comprehensive review of the structure and function of the AR and clinical evidence for targeting the cell's nuclear receptor in TNBC. We updated AR agonists, inhibitors, and antagonists. We also presented a new era of genetic manipulating CRISPR/Cas9 and nanotechnology as state-of-the-art approaches against AR to promote the efficiency of targeted therapy in TNBC. SIGNIFICANCE STATEMENT: The lack of effective treatment for triple-negative breast cancer is a health challenge. The main disadvantages of existing treatments are their side effects, due to their nonspecific targeting. Molecular targeting of cellular receptors, such as androgen receptors, increased expression in malignant tissues, significantly improving the survival rate of breast cancer patients.

Human In Vivo Metabolism and Elimination Behavior of Micro-Dosed Selective Androgen Receptor Modulator RAD140 for Doping Control Purposes

RAD140 is a selective androgen receptor modulator which has been abused in sporting competitions. Its use is prohibited by the World Anti-Doping Agency (WADA) for athletes at all times. In addition to its illicit use, adverse analytical findings of RAD140 in doping control samples might result from other scenarios, e.g., the ingestion of contaminated dietary supplements. The differentiation between samples resulting from such contamination scenarios and intentional doping presents a considerable challenge, as little is known about the metabolism and elimination behavior of RAD140 in humans. In this study, six micro-dose excretion studies with five adult male volunteers each were conducted, and urine samples were analyzed by means of LC-HRMS/MS. Multiple metabolites, firstly detected in human urine, are described in this study. The sample preparation included an enzymatic hydrolysis step, which facilitated the estimation of RAD140 concentrations in urine. The elimination profiles and detection times for six metabolites as well as the intact drug are presented. The method was extensively characterized and deemed fit-for-purpose. The metabolite ratios were investigated for their predictive power in estimating the dose of RAD140 intake. The presented data will aid in better case result management in future doping cases involving RAD140.