Relugolix: A Review in Advanced Prostate Cancer

Urolithins: Emerging natural compound targeting castration-resistant prostate cancer (CRPC)

Castration-resistant prostate cancer (CRPC) presents a significant challenge due to its resistance to conventional androgen deprivation therapies. Urolithins, bioactive metabolites derived from ellagitannins, have recently emerged as promising therapeutic agents for CRPC. Urolithins not only inhibit androgen receptor (AR) signaling, a crucial factor in the progression of CRPC, but also play a key role in regulating oxidative stress by their antioxidant properties, thereby inhibiting increased reactive oxygen species, a common feature of the aggressive nature of CRPC. Research has shown that urolithins induce apoptosis and diminish pro-survival signaling, leading to tumor inhibition. This review delves into the intricate mechanisms through which urolithins exert their therapeutic effects, focusing on both AR-dependent and AR-independent pathways. It also explores the exciting potential of combining urolithins with androgen ablation therapy, opening new avenues for CRPC treatment.

Safety and Tolerability of Relugolix in Combination with Abiraterone or Apalutamide for Treatment of Patients with Advanced Prostate Cancer: Data from a 52-Week Clinical Trial

BACKGROUND

The gonadotropin-releasing hormone (GnRH) receptor antagonist relugolix is the only oral androgen deprivation therapy (ADT) indicated for advanced prostate cancer (aPC). Combining ADT with androgen receptor signaling inhibitors (ARSIs) has shown improved clinical outcomes.

OBJECTIVE

To assess the safety, tolerability, pharmacokinetics, and pharmacodynamics of relugolix in combination with ARSIs in patients with aPC.

METHODS

In this 52-week, open-label study, patients received relugolix (120 mg once daily) with abiraterone (1,000 mg once daily) and corticosteroid (Part 1) or relugolix (240 mg once daily) with apalutamide (240 mg once daily) (Part 2). Metastatic castration-sensitive patients were eligible for both parts, whereas castration-resistant patients were eligible for Part 1 if metastatic and Part 2 if non-metastatic. Adverse events and other safety data were evaluated over 52 weeks, while pharmacodynamic and pharmacokinetic (Part 2 only) data were assessed over 12 weeks. Medication adherence to relugolix was measured by pill count.

RESULTS

Of 48 patients, 21 completed Part 1 and 20 completed Part 2. Most adverse events were grade 1 or 2, with hypertension (Part 1) and rash (Part 2) being most common. Mean testosterone concentrations remained below castrate level. Median prostate-specific antigen concentration was 0.04 ng/mL at week 12 in both parts. Concentrations of relugolix, apalutamide, and N-desmethyl-apalutamide were stable over 12 weeks similar to previous data. Relugolix adherence rates were > 97% in both parts.

CONCLUSIONS

The safety/tolerability profile of both combination therapies was consistent with those of the individual drugs. These findings support using relugolix in combination with abiraterone or apalutamide as treatment of aPC.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov identifier NCT04666129.

New endocrine method of oral male contraception

Essential for hormonal male contraception (HMC) is the inhibition of follicle-stimulating hormone (FSH), the hormone responsible for spermatogenesis. No drugs exist that can selectively suppress FSH without also inhibiting luteinizing hormone (LH), the hormone responsible for the biosynthesis of testosterone (T) and estradiol (E2) in men. The consequences are a loss of T and E2, with the accompanying symptoms and signs of T deficiency and E2 deficiency, respectively. The loss of T causes sexual function problems, including reduced libido and problems with erection and ejaculation. Moreover, T is not orally bioavailable, and there is a lack of suitable, orally bioavailable androgens to replace the loss of T. This has led to the use of nonoral T replacements, such as patches, gels, or parenteral administration of T or other androgens in current methods for HMC under development. In case these new HMC methods do not contain a testosterone preparation that is metabolized into E2, the suppression of LH will cause loss of E2 and symptoms of estrogen deficiency. We propose to investigate a new oral endocrine approach for HMC using a triple hormone drug called MANTE (Male oral contraception by a GnRH ANtagonist, Testosterone and an Estrogen). This method combines three novelties: (1) the use of an oral gonadotrophin-releasing hormone antagonist to suppress FSH and spermatogenesis, (2) a high dose of the natural adrenal androgen dehydroepiandrosterone to replace T, and (3) a low dose of an orally bioavailable estrogen, preferably estetrol (E4), to prevent signs and symptoms of estrogen deficiency.

Transfer of the Oral Gonadotropin-Releasing Hormone Receptor Antagonist Relugolix Into Breast Milk of Healthy Lactating Women

Relugolix is an oral gonadotropin-releasing hormone receptor antagonist that suppresses sex steroid hormones and is approved as monotherapy for prostate cancer and as a fixed-dose combination with estradiol/norethindrone for the treatment of endometriosis and uterine fibroids. The aim of this postmarketing study was to determine the pharmacokinetics and quantify the amount of relugolix excreted into breast milk of healthy lactating women. Following a single, oral dose of 40 mg relugolix, breast milk was sampled over 120 h. Pharmacokinetic parameters were determined, including the cumulative amount of relugolix excreted into breast milk to derive the total infant dose. The safety and tolerability of relugolix were also assessed. Eight healthy lactating women were enrolled and completed the study per protocol. Relugolix was safe and well tolerated based on adverse events and other safety data. It was excreted into breast milk with a median time to peak concentration (tmax) of 5.81 h and a geometric mean peak concentration (Cmax) of 15.7 ng/mL, similar to corresponding plasma data from previous clinical studies. The mean cumulative amount of relugolix excreted was 0.0051 mg over 24 h and 0.0067 mg over 120 h, corresponding to 0.0128% and 0.0167% of the maternal dose, respectively. The body weight-adjusted relative daily infant dose of approximately 0.25% suggests a 400-fold lower newborn than maternal relugolix exposure. Relevant effects of relugolix on the breastfed child appear unlikely given its limited excretion into breast milk of lactating women but cannot be fully excluded in the absence of infant safety data.

The Role of Ayurveda in Prostate Cancer Management

Ayurveda is commonly utilized in the treatment of medical ailments but has yet to gain traction in incorporation into allopathic medicine. Prostate cancer is the most common cancer among men and presents a significant public health burden across the globe. Despite advancements in the management of advanced prostate cancer including androgen deprivation therapy and novel hormonal therapies, men may eventually develop resistance to hormonal therapy. As such, there is an urgent need for novel therapeutic options in treating this malignancy. This review examines the pre-clinical evidence for Ayurveda medicinal plants such as Withania somnifera, Glycyrrhiza spp, Momordica spp, Boswellia, and Bacopa monnieri and their potential application in managing prostate cancer. Several in-vitro and pre-clinical studies suggest potentials for these plants or their derivatives in preventing or treating prostate cancers. Despite strong evidence of efficacy of these plants to potentially improve the outcome of prostate cancer, clinical trials are required to evaluate which plants may be most efficacious and to determine effective dosing strategies, as well as the use of ayurvedic plants as standalone therapies or in combination with conventional prostate cancer treatments.

Adverse events analysis of Relugolix (Orgovyx®) for prostate cancer based on the FDA Adverse Event Reporting System (FAERS)

BACKGROUND

Due to the limitations of clinical trials, some delayed and rare adverse events (AEs) may remain undetected, and safety information can be supplemented through post-market data analysis. This study aims to comprehensively analyze the AEs associated with Relugolix (Orgovyx®) using data from the FAERS database, and gain a better understanding of the potential risks and side effects of Relugolix (Orgovyx®) therapy.

METHODS

Data of Relugolix (Orgovyx®) were collected from the FAERS database covering the period from the fourth quarter of 2020 to the third quarter of 2023. Disproportionality analysis was performed by calculating the reporting odds ratios (ROR), proportional reporting ratio (PRR), Bayesian analysis confidence propagation neural network (BCPNN), and the multi-item gamma Poisson shrinker (MGPS) to detect positive signals.

RESULTS

Totally, 5,382,189 reports were collected from the FAERS database, 4,397 reports of Relugolix (Orgovyx®) were identified as the 'primary suspected (PS)' AEs. Relugolix (Orgovyx®) induced AEs occurred in 26 organ systems. 58 significant disproportionality preferred terms (PTs) satisfying with the four algorithms were retained at the same time. Unexpected significant AEs such as Pollakiuria, and Prostatic specific antigen increased also occur. The median time of onset was 60 days. The majority of the AEs occurred within the first 30 days after Relugolix (Orgovyx®) initiation.

CONCLUSION

Common AEs included Hot flush, Fatigue, Asthenia, Constipation, and Myalgia. These AEs should be focused on when using the drug to avoid serious consequences. In addition, the study results also suggested that the drug may exist Pollakiuria, Prostatic specific antigen increased and other AEs not mentioned in the manual, to supplement the AEs in the manual. This study is helpful for clinicians and pharmacists to improve their understanding of Relugolix (Orgovyx®) related AEs, and take timely prevention and treatment measures to ensure drug safety for patients.

The Effect of Androgen Deprivation Therapy on the Cardiovascular System in Advanced Prostate Cancer

Androgen deprivation therapy (ADT) is a mainstay treatment for metastatic prostate cancer, improving progression-free survival. ADT suppresses the production of testosterone and reduces circulating levels of the hormone. Luteinizing hormone-releasing hormone (LH-RH) agonists are the most commonly used ADT modality. They can be given alone or in combination with androgen synthesis inhibitors or androgen receptor antagonists. An estimated 40% of prostate cancer patients will receive ADT as part of their therapy during their lifetime. However, ADT has numerous adverse effects, including an increased cardiovascular risk that impacts quality of life. Relugolix is an alternative form of ADT. It is the only oral gonadotropin-releasing hormone antagonist, circumventing injection site reactions, making it easier for patients to take, and thus increasing compliance. Testosterone suppression with relugolix is excellent and testosterone recovery after discontinuation is rapid. This paper reviews the ADT and anti-androgen treatment options for men with prostate cancer and the cardiovascular effects of these therapies. There is accumulating evidence that cardiovascular risk with relugolix is lower than with other ADT medications and also lower than with androgen synthesis inhibitors and androgen receptor antagonists. This paper provides insight into the use of different ADT regimens based on the cardiovascular status and circumstances. It explores strategies to mitigate negative cardiovascular consequences and highlights the need for further study.

Relugolix Plus Enzalutamide For Metastatic Hormone-Sensitive Prostate Cancer: A Case Report

Background

In the UK, relugolix, an oral gonadotropin-releasing hormone receptor antagonist, is indicated for advanced hormone-sensitive prostate cancer, and as neo-adjuvant and adjuvant treatment in combination with radiotherapy in patients with high-risk localised or locally advanced hormone-dependent prostate cancer. Experience with the combination of oral relugolix plus oral enzalutamide is limited.

Case Presentation

A white British male (66 years old) with a history of myelodysplastic syndrome, chronic neutropenia and indeterminate colitis presented with metastatic adenocarcinoma of the prostate gland. The patient started subcutaneous leuprorelin acetate and oral enzalutamide. After 8 weeks, the oral enzalutamide dose was reduced because of fatigue. Following the second leuprorelin injection, the patient developed a subcutaneous abscess that required surgical incision and drainage. The patient switched to oral relugolix and continued with oral enzalutamide. Within 3 months of commencing leuprorelin and enzalutamide the prostate specific antigen (PSA) concentration fell from a peak of 269.00 ng/mL to 2.55 ng/mL. Following the switch to oral relugolix plus enzalutamide, the PSA remained stable until the most recent assessment 11 months later. Relugolix plus enzalutamide was well tolerated.

Conclusion

Relugolix plus enzalutamide produced a sustained reduction in PSA and the combination was well tolerated. Further research including real world data should assess relugolix in doublet and triplet combinations for prostate cancer.

Synthetic approaches and application of representative clinically approved fluorine-enriched anti-cancer medications

Fluorine possesses distinctive chemical characteristics, such as its strong electron-withdrawing ability and small atomic size, which render it an invaluable asset in the design and optimization of pharmaceuticals. The utilization of fluorine-enriched medications for combating cancer has emerged as a prominent approach in medicinal chemistry and drug discovery, offering improved clinical outcomes and enhanced pharmacological properties. This comprehensive review explores the synthetic approaches and clinical applications of approved 22 representative fluorinated anti-cancer drugs from 2019 to present, shedding light on their historical development, brand names, drug target activity, mechanism of action, preclinical pharmacodynamics, clinical efficacy, and toxicity. Additionally, the review provides an extensive analysis of the representative synthetic techniques employed. Overall, this review emphasizes the significance of incorporating fluorine chemistry into anti-cancer drug research while highlighting promising future prospects for exploring compounds enriched with fluorine in the battle against cancer.