Real-world study: Impact of multidisciplinary management of apalutamide-associated adverse events in prostate cancer.

OBJECTIVE: To analyse the adverse events (AEs) associated with apalutamide and the impact of a multidisciplinary team (MDT) protocol on its management at a tertiary care hospital in a real-world setting. METHODS: This was an observational, prospective, cohort study based on real-world evidence at the Hospital Clínic de Barcelona. Includes patients diagnosed with metastatic hormone-sensitive prostate cancer (mHSPC) or high-risk nonmetastatic castration-resistant prostate cancer (nmCRPC) and who started treatment with apalutamide between May 2019 and March 2023 in a real-world clinical setting. RESULTS: Of the 121 patients treated with apalutamide, 52.1% experienced an AE, 19.8% experienced temporarily interruption or a reduction in the dose of apalutamide, and 13.2% discontinued treatment due to AEs. Without MDT protocol (49 patients), 24.5% of patients had to temporarily interrupt or reduce the dose of apalutamide due to AEs, with a median time from the start of treatment of 10.1 months, and 24.5% discontinued apalutamide due to AEs, with a median time from the start of treatment of 3.1 months. Meanwhile, whit MDT protocol (72 patients), 16.7% of patients had to temporarily interrupt or reduce the dose of apalutamide due to AEs, with a median time from the start of treatment of 1.6 months, and 5.6% discontinued apalutamide due to AEs, with a median time from the start of treatment of 4 months. The risk reduction associated with treatment discontinuation was statistically significant (p-value = 0.003). CONCLUSIONS: This study highlights the importance of MDT management of AEs associated with apalutamide to reduce treatment discontinuation.

CAPN2 promotes apalutamide resistance in metastatic hormone-sensitive prostate cancer by activating protective autophagy.

Apalutamide, a novel endocrine therapy agent, has been shown to significantly improve the prognosis of patients with metastatic hormone-sensitive prostate cancer (mHSPC). However, resistance to apalutamide has also been reported, and the underlying mechanism for this response has yet to be clearly elucidated. First, this study established apalutamide-resistant prostate cancer (PCa) cells, and confirmed that apalutamide activated the release of calcium ions (Ca2+) and endoplasmic reticulum stress (ERS) to enhance autophagy. Second, RNA sequencing, western blotting, and immunohistochemistry revealed significantly decreased Calpain 2 (CAPN2) expression in the apalutamide-resistant PCa cells and tissues. Furthermore, immunofluorescence and transmission electron microscopy (TEM) showed that CAPN2 promoted apalutamide resistance by activating protective autophagy. CAPN2 promoted autophagy by reducing Forkhead Box O1 (FOXO1) degradation while increasing nuclear translocation via nucleoplasmic protein isolation and immunofluorescence. In addition, FOXO1 promoted protective autophagy through the transcriptional regulation of autophagy-related gene 5 (ATG5). Furthermore, a dual-fluorescence assay confirmed that transcription factor 3 (ATF3) stimulation promoted CAPN2-mediated autophagy activation via transcriptional regulation. In summary, CAPN2 activated protective autophagy by inhibiting FOXO1 degradation and promoting its nuclear translocation via transcriptional ATG5 regulation. ATF3 activation and transcriptional CAPN2 regulation jointly promoted this bioeffect. Thus, our findings have not only revealed the mechanism underlying apalutamide resistance, but also provided a promising new target for the treatment of metastatic PCa.

Protocol for CHAMPION study: a prospective study of maximal-cytoreductive therapies for patients with de novo metastatic hormone-sensitive prostate cancer who achieve oligopersistent metastases during systemic treatment with apalutamide plus androgen deprivation therapy.

BACKGROUND: The proposed trial is to examine the feasibility of prostate-specific membrane antigen (PSMA) positron emission tomography/computed tomography (PET/CT)-guided cytoreduction plus apalutamide and androgen deprivation therapy (ADT) for newly diagnosed metastatic hormone-sensitive prostate cancer (mHSPC) at oligometastatic state. METHODS: CHAMPION (NCT05717582) is an open-label, single-arm, phase II trial, planning to enroll newly diagnosed mHSPC cases with oligometastases (≤ 10 distant metastatic sites in conventional imaging). Patients will receive 6 cycles of apalutamide plus ADT. Patients with oligometastatic disease at PSMA PET/CT after 3 treatment cycles will receive cytoreductive radical prostatectomy. PSMA PET/CT-guided metastasis-directed external radiation therapy will be determined by the investigators. Apalutamide plus ADT will be continued for 2 weeks postoperatively. The primary endpoint is the proportion of patients with undetectable prostate-specific antigen (PSA), no disease progression, and no symptom deterioration after 6 cycles of apalutamide plus ADT. Secondary endpoints include the percentage of patients with PSA ≤ 0.2 ng/mL and oligometastases by the end of 3 treatment cycles, PSA response rate, and safety. Fleming's two-stage group sequential design will be adopted in the study, where the null hypothesis is that the rate of patients with an undetectable PSA is ≤ 40% after 6 cycles of treatment, while the alternate hypothesis is an undetectable PSA of > 60%; with one-sided α = 0.05, power = 0.80, and an assumed dropout rate of 10%, the required number of patients for an effective analysis is 47. Enrolment in the study commenced in May 2023. DISCUSSION: The multi-modal therapy based on treatment response may improve the prognosis of newly diagnosed mHSPC patients with oligometastases. TRIAL REGISTRATION: The study is registered with Clinical Trials.Gov (NCT05717582). Registered on 8th February 2023.

A phase II trial of apalutamide for intermediate-risk prostate cancer and molecular correlates.

OBJECTIVES: To determine whether 6 months of preoperative apalutamide for intermediate-risk prostate cancer (IRPCa) reduces the aggregate postoperative radiotherapy risk and to evaluate associations of molecular perturbations with clinical outcomes in this study cohort. PATIENTS AND METHODS: Between May 2018 and February 2020, eligible patients with IRPCa (Gleason 3 + 4 or 4 + 3 and clinical T2b-c or prostate-specific antigen level of 10-20 ng/mL) were treated with apalutamide 240 mg/day for 6 months followed by radical prostatectomy (RP) in this single-arm, phase II trial. The primary endpoint was presence of any adverse pathological feature at risk of pelvic radiation (pathological T stage after neoadjuvant therapy [yp]T3 or ypN1 or positive surgical margins). Translational studies, including germline and somatic DNA alterations and RNA and protein expression, were performed on post-apalutamide RP specimens, and assessed for associations with clinical outcomes. RESULTS: A total of 40 patients underwent a RP, and only one patient discontinued apalutamide prior to 6 months. In all, 40% had adverse pathological features at time of RP, and the 3-year biochemical recurrence (BCR) rate was 15%, with 27.5% being not evaluable. Genomic alterations frequently seen in metastatic PCas, such as androgen receptor (AR), tumour protein p53 (TP53), phosphatase and tensin homologue (PTEN), or BReast CAncer associated gene (BRCA1/2) were underrepresented in this localised cohort. Adverse pathological features and BCR at 3-years were associated with increased expression of select cell cycle (e.g., E2F targets: adjusted P value [Padj] < 0.001, normalised enrichment score [NES] 2.47) and oxidative phosphorylation (Padj < 0.001, NES 1.62) pathways. CONCLUSIONS: Preoperative apalutamide did not reduce the aggregate postoperative radiation risk to the pre-specified threshold in unselected men with IRPCa. However, transcriptomic analysis identified key dysregulated pathways in tumours associated with adverse pathological outcomes and BCR, which warrant future study. Further investigation of preoperative therapy is underway for men with high-risk PCa.

Real-world analysis of apalutamide-associated skin rash in Chinese patients with prostate cancer.

PURPOSE: This study aimed to explore the clinical characteristics of apalutamide-associated skin rash and management of skin rash in real-world Chinese patients with prostate cancer. METHODS: We investigated 138 patients with prostate cancer who received apalutamide in the Second Hospital of Tianjin Medical University from January 2022 to March 2023. The primary end points were the incidence of skin rash and the time to skin rash. The second end points were the grade of skin rash, the time to remission, the rate of recurrence of skin rash, clinical risk factors and management of skin rash. RESULTS: One hundred patients were analyzed. Patients were a median of 73 years old (IQR 68-77.75). Thirty-two patients (32%) developed apalutamide­associated skin rash. The median time to incidence and remission of skin rash were 57.5 and 11.5 days, respectively. Of 32 skin rash, 27 patients had apalutamide therapy maintained after rash remission. There were seven patients having recurrence of skin rash. By multivariable logistic regression analysis, we revealed that hypertension history (OR 3.22, 95% CI 1.09-9.53, p = 0.035), bad life-styles (OR 3.29, 95% CI 1.11-9.8, p = 0.032), ECOG ≥ 1 (OR 3.92, 95% CI 1.33-11.55, p = 0.013), and high tumor burden (OR 3.13, 95% CI 1.07-9.14, p = 0.037) were independently associated with higher incidence of skin rash. CONCLUSION: Nearly one-third of Chinese patients experienced skin rash after taking apalutamide in our study. The poor health patients might have a higher incidence of apalutamide-associated skin rash.

Design, Characterization and Biopharmaceutical Applications of Novel Green Boron-Carbon Quantum Dots for Quantification of Apalutamide; Greenness Evaluations.

The diagnosis of prostate cancer has been evolving in the current decade, with expected mortality rates of 499,000 death by the year 2030. Apalutamide (APL) has been approved in 2018 as the first drug for the controlling of prostate cancer. APL significant success warrantied its high global sales, which are expected to surpass 58% of segment market sales (together with another drug; enzalutamide). Therefore, new, fast and environmentally friendly analytical methods are required for its determination for the quality control and biological monitoring purposes. The proposed research designs and evaluates the first fluorimetric approach based on novel porous green boron-doped carbon quantum dots (B@CDs) for the determination of APL in biopharmaceutical matrices. The synthetic approach has high quantum yield (31.15%). B@CDs were characterized using several tools, including transmission electron microscopy (TEM), dynamic light scattering (DLS), FTIR and Energy dispersive X-ray spectroscopy (EDX) which proved their improved surface properties with an average nano-diameter of 3.0 nm. The interaction between B@CDs and APL led to enhancement their fluorescence at 441 nm (excitation at 372 nm). The approach was validated for the determination of APL within concentration range of 15.0-700.0 ng mL- 1 with quantification limit LOQ 4.37 ng mL- 1 and detection limit LOD 1.44 ng mL- 1. The approach was successfully applied for the determination of APL in human plasma and pharmaceutical monitoring of its marketed tablet form. Then, the approach was assessed for its environmental impact using different metrics and proved its ecological greenness.

Real-world clinical outcomes among patients with metastatic castration-sensitive prostate cancer initiating apalutamide.

Aim: To describe overall survival, time to castration resistance and castration resistance-free survival in patients with metastatic castration-sensitive prostate cancer (mCSPC) initiating apalutamide in a US oncology network. Patients & methods: Patients with mCSPC initiating apalutamide on or after 17 September 2019 from an electronic health record-derived deidentified database were included. Patients were followed from apalutamide initiation and were censored at the earlier of end of clinical activity or data availability (31 October 2022). Results: At 12 and 24 months, overall survival rates were 91.0 and 88.3%, rates of castration sensitivity were 85.7 and 72.1%, and castration resistance-free survival rates were 80.2 and 65.9%, respectively. Conclusion: Real-world clinical outcomes of patients with mCSPC treated with apalutamide were comparable to results from the phase III TITAN trial.

This study looked at health outcomes among 176 patients receiving a prostate cancer medication, apalutamide. The average age of patients was 72 years, and approximately two-thirds of patients were White. Two years after starting apalutamide, most patients remained alive and their cancer did not progress.

Prostate-specific antigen (PSA) decline with apalutamide therapy is associated with longer survival and improved outcomes in individuals with metastatic prostate cancer: a plain language summary of the TITAN study.

WHAT IS THIS SUMMARY ABOUT?: This summary describes the results from an additional (or post hoc) analysis of the TITAN study. The TITAN study looked at whether the prostate cancer treatment apalutamide could be used to treat individuals with metastatic castration-sensitive prostate cancer (or mCSPC). A total of 1052 participants with mCSPC were included in the TITAN study. Treatment with apalutamide was compared with treatment with placebo. All participants received androgen deprivation therapy (or ADT), which is a type of hormone therapy that has been part of the main treatment for mCSPC for many years. The results showed that apalutamide plus ADT increased the length of time that participants remained alive compared with placebo plus ADT. Apalutamide plus ADT also controlled the growth of the cancer for a longer length of time compared with placebo plus ADT. Additionally, participants who received apalutamide plus ADT experienced a greater reduction in the blood levels of prostate-specific antigen (or PSA), called a deep PSA decline, compared with those who received placebo plus ADT. An additional (or post hoc) analysis was carried out to understand whether a decrease in blood PSA levels, in response to treatment, was associated with improved outcomes, including longer survival time. WHAT WERE THE RESULTS OF THE ADDITIONAL ANALYSIS?: In participants who received apalutamide plus ADT, a deep PSA decline in response to treatment was associated with longer survival time and improved outcomes. WHAT DO THESE RESULTS MEAN FOR INDIVIDUALS WITH MCSPC?: These results demonstrate that individuals with mCSPC can benefit from treatment with apalutamide plus ADT. The association seen between deep PSA decline and the longer survival time and improved outcomes highlights how PSA measurements can be used to help monitor cancer disease evolution in response to treatment. Monitoring PSA levels will assist doctors and other healthcare professionals to understand how effectively a treatment is working for a patient and to tailor their treatment approach to improve PSA decline.

Real-world prostate-specific antigen response and progression to castration-resistant prostate cancer among men with metastatic castration-sensitive prostate cancer treated with apalutamide: a multi-institutional study in the Chu-shikoku Japan Urological Consortium.

BACKGROUND: Japanese men receiving apalutamide often experience skin-adverse events (AEs), possibly requiring treatment interruption or dose reduction. However, concerns have arisen regarding the impact of these adjustments on the efficacy of apalutamide. Our study evaluated the efficacy, safety, and persistence of apalutamide in men with metastatic castration-sensitive prostate cancer (mCSPC). METHODS: We retrospectively reviewed the medical records of 108 men with mCSPC from 14 Japanese institutions. The primary outcomes were the efficacy of apalutamide: prostate-specific antigen (PSA) response (50%, 90% and < 0.2 decline) and progression to castration-resistant prostate cancer (CRPC). The secondary outcomes were the skin-AE and compliance of apalutamide. RESULTS: PSA50%, PSA90% and PSA < 0.2 declines were observed in 89.8, 84.3 and 65.7%, and the median time to CRPC progression was not reached. PSA < 0.2 decline and an initial full dose of apalutamide were significantly associated with a longer time to CRPC. The most common AE was skin-AE (50.9%), and there was no association between the occurrence of skin-AE and the time to CRPC (P = 0.72). The median apalutamide persistence was 29 months, which was longer in the initial full dose recipients than in the reduced dose recipients. The dosage is reduced in about 60% of patients within the first year of treatment in the initial full dose recipients. CONCLUSIONS: Our findings indicate the effectiveness of apalutamide in Japanese men with mCSPC, despite a substantial portion requiring dose reduction within a year among the initial full dose recipients.

Effectiveness and safety of enzalutamide and apalutamide in the treatment of patients with non-metastatic castration-resistant prostate cancer (nmCRPC): a multicenter retrospective study.

OBJECTIVE: Phase III clinical trials demonstrated the efficacy of enzalutamide and apalutamide in patients with non-metastatic castration-resistant prostate cancer (nmCRPC) and PSA doubling time ≤10 months. Although these drugs have been shown to vary in their adverse event (AE) profiles, the differences in their efficacy profiles remain to be evaluated. Therefore, this retrospective study was conducted to evaluate the efficacy of these drugs in patients with nmCRPC. METHODS: This study evaluated 191 patients with nmCRPC treated with enzalutamide (n = 137) or apalutamide (n = 54) in the first-line setting at Jikei University Hospital or its affiliated hospitals between May 2014 and November 2022. Endpoints were defined as oncological outcomes (i.e., PSA response, PFS, PSA-PFS, MFS, CSS, and OS) and AEs. RESULTS: No significant differences were noted in patient backgrounds between the two groups. Patients exhibiting a maximum PSA response of >50% and >90% accounted for 74.5% and 48.9% of patients in the enzalutamide group, and 75.9% and 42.6% of patients in the apalutamide group, respectively, with no significant difference between the groups. The median PSA-PFS was 10 months in the enzalutamide group but not in the apalutamide group, with no significant difference between the groups (P = 0.48). No significant differences were observed in MFS, CSS, or OS between the groups. Patients reporting AEs of all grades and grade 3 or higher accounted for 56.2% and 4.3% of those in the enzalutamide group and 57.4% and 7.4% of those in the apalutamide group, respectively. The most common AE was fatigue (26.3%) in the enzalutamide group and skin rash (27.8%) in the apalutamide group. CONCLUSION: In this retrospective study of their efficacy and safety, enzalutamide and apalutamide were shown to exhibit comparable oncological outcomes but quite different AE profiles, suggesting that their differential use may be warranted based on these findings.

Mitochondrial Elongation and ROS-Mediated Apoptosis in Prostate Cancer Cells under Therapy with Apalutamide and Complex I Inhibitor.

Metabolic reprogramming and mitochondrial dynamics are pivotal in prostate cancer (PCa) progression and treatment resistance, making them essential targets for therapeutic intervention. In this study, we investigated the effects of the androgen receptor antagonist apalutamide (ARN) and the mitochondrial electron transport chain complex I inhibitor IACS-010759 (IACS) on the mitochondrial network architecture and dynamics in PCa cells. Treatment with ARN and/or IACS induced significant changes in mitochondrial morphology, particularly elongation, in androgen-sensitive PCa cells. Additionally, ARN and IACS modulated the mitochondrial fission and fusion processes, indicating a convergence of metabolic and androgen-signaling pathways in shaping mitochondrial function. Notably, the combination treatment with ARN and IACS resulted in increased apoptotic cell death and mitochondrial oxidative stress selectively in the androgen-sensitive PCa cells. Our findings highlight the therapeutic potential of targeting mitochondrial metabolism in prostate cancer and emphasize the need for further mechanistic understanding to optimize treatment strategies and improve patient outcomes.

Pathological Effects of Apalutamide in Lower-risk Prostate Cancer: Results From a Phase II Clinical Trial.

PURPOSE: Active surveillance is a safe and effective strategy for men with lower-risk prostate cancer who want to avoid local therapy; however, many patients on active surveillance progress to active treatment (eg, prostatectomy or radiation). We hypothesized that apalutamide would decrease active surveillance attrition rates through downstaging low-grade tumors. MATERIALS AND METHODS: This was an open-label, single-arm, phase II study testing 90 days of oral apalutamide 240 mg daily in men with low- to intermediate-risk prostate cancer on active surveillance. The primary objective was to determine the percentage of patients with a negative biopsy immediately following treatment. Secondary objectives were to assess long-term clinical outcomes, quality of life, safety, and biomarkers of response/resistance. RESULTS: Twenty-three patients enrolled and 22 completed 90 days of apalutamide with post-treatment biopsy. Fifteen (65%) had Grade Group 1 disease, and all others had Grade Group 2 disease. Seven (30%) had favorable- to intermediate-risk disease. Of 22 evaluable patients, 13 (59%) had no residual cancer on post-treatment biopsy. The median time to first positive biopsy was 364 days (95% CI: 91-742 days). The impact of apalutamide on quality of life was minimal and transient. Decipher risk classifier revealed a greater number of negative post-treatment biopsies in those with higher baseline genomic risk score (P = .01). CONCLUSIONS: The negative repeat biopsy rate following 90 days of apalutamide was high in men with prostate cancer followed on active surveillance. Apalutamide was safe, well tolerated, and had minimal impact on quality of life. Randomized studies evaluating the effects of apalutamide in men enrolled on active surveillance are warranted.

Artepillin C overcomes apalutamide resistance through blocking androgen signaling in prostate cancer cells.

Prostate cancer has a relatively good prognosis, but most cases develop resistance to hormone therapy, leading to castration-resistant prostate cancer (CRPC). Androgen receptor (AR) antagonists and a cytochrome P450 17A1 inhibitor have been used to treat CRPC, but cancer cells readily develop resistance to these drugs. In this study, to improve the therapy of CRPC, we searched for natural compounds which block androgen signaling. Among cinnamic acid derivatives contained in Brazilian green propolis, artepillin C (ArtC) suppressed expressions of androgen-induced prostate-specific antigen and transmembrane protease serine 2 in a dose-dependent manner. Reporter assays revealed that ArtC displayed AR antagonist activity, albeit weaker than an AR antagonist flutamide. In general, aberrant activation of the androgen signaling is involved in the resistance of prostate cancer cells to hormone therapy. Recently, apalutamide, a novel AR antagonist, has been in clinical use, but its drug-resistant cases have been already reported. To search for compounds which overcome the resistance to apalutamide, we established apalutamide-resistant prostate cancer 22Rv1 cells (22Rv1/APA). The 22Rv1/APA cells showed higher AR expression and androgen sensitivity than parental 22Rv1 cells. ArtC inhibited androgen-induced proliferation of 22Rv1/APA cells by suppressing the enhanced androgen signaling through blocking the nuclear translocation of AR. In addition, ArtC potently sensitized the resistant cells to apalutamide by inducing apoptotic cell death due to mitochondrial dysfunction. These results suggest that the intake of Brazilian green propolis containing ArtC improves prostate cancer therapy.

Allosteric inhibition of HSP70 in collaboration with STUB1 augments enzalutamide efficacy in antiandrogen resistant prostate tumor and patient-derived models.

Ubiquitin proteasome activity is suppressed in enzalutamide resistant prostate cancer cells, and the heat shock protein 70/STIP1 homology and U-box-containing protein 1 (HSP70/STUB1) machinery are involved in androgen receptor (AR) and AR variant protein stabilization. Targeting HSP70 could be a viable strategy to overcome resistance to androgen receptor signaling inhibitor (ARSI) in advanced prostate cancer. Here, we showed that a novel HSP70 allosteric inhibitor, JG98, significantly suppressed drug-resistant C4-2B MDVR and CWR22Rv1 cell growth, and enhanced enzalutamide treatment. JG98 also suppressed cell growth in conditional reprogramed cell cultures (CRCs) and organoids derived from advanced prostate cancer patient samples. Mechanistically, JG98 degraded AR/AR-V7 expression in resistant cells and promoted STUB1 nuclear translocation to bind AR-V7. Knockdown of the E3 ligase STUB1 significantly diminished the anticancer effects and partially restored AR-V7 inhibitory effects of JG98. JG231, a more potent analog developed from JG98, effectively suppressed the growth of the drug-resistant prostate cancer cells, CRCs, and organoids. Notably, the combination of JG231 and enzalutamide synergistically inhibited AR/AR-V7 expression and suppressed CWR22Rv1 xenograft tumor growth. Inhibition of HSP70 using novel small-molecule inhibitors coordinates with STUB1 to regulate AR/AR-V7 protein stabilization and ARSI resistance.

Current status and future perspectives of the managements of metastatic hormone-sensitive prostate cancer.

PURPOSE: The therapeutic landscape for metastatic hormone-sensitive prostate cancer (mHSPC) has changed dramatically. Here, we provide the current status and future prospective of the management of mHSPC. METHODS: We reviewed recent literature of landmark studies on the managements of mHSPC. RESULTS: Upfront docetaxel or androgen receptor signaling inhibitor (ARSi) in addition to ADT has improved survival in mHSPC patients and has become the new standard of care. Triplet therapy with docetaxel, ARSi and ADT also improved survival. In the future, triplet therapy may become the standard of care. Oligometastatic mHSPC patients could benefit from local therapy. The inclusion of risk factors or the genetic biomarkers will provide the best treatment for individual mHSPC patients. CONCLUSION: Strong systemic therapy in the first-line treatment of mHSPC has been shown to improve survival and quality of life. Currently, several clinical trials are evaluating novel compounds such as PARP inhibitor, AKT inhibitor, and immune checkpoint inhibitor. The therapeutic landscape of mHSPC management will change dramatically.

Pharmacokinetic Interactions Between Abiraterone, Apalutamide, Darolutamide or Enzalutamide and Antithrombotic Drugs: Prediction of Clinical Events and Review of Pharmacological Information.

PURPOSE: Abiraterone, apalutamide, darolutamide and enzalutamide are second-generation hormone therapies used for advanced prostate cancer; the majority of patients receiving these treatments are elderly, poly-medicated patients. Since their first market authorizations, their pharmacokinetic (PK) characteristics are increasingly well known. A potential risk of drug-drug interaction (DDI), especially with cardiovascular drugs, needs to be considered. In the case of antithrombotics, treatment imbalance can lead to severe consequences. OBJECTIVES: To describe PK profiles of hormone therapies and antithrombotics and to predict DDIs and potentially related clinical events. METHODS: PK profiles (CYP450 and P-gp substrate, inducer or inhibitor) are described by cross-referencing data sources (summary of product characteristics, European public assessment reports, PubMed database, Micromedex®, etc.); a description of the potential interactions with anti-cancer drugs for each DDI and related clinical events is provided. We discuss management recommendations, including those set out in international guidelines. RESULTS: Antithrombotics are mainly metabolized by CYP 2C9, 2C19 or 3A4. For abiraterone (CYP 2C8, 2D6 inhibitor) and darolutamide (CYP 3A4 inducer), no interaction was identified with antithrombotics. For apalutamide (CYP 2C9, 2C19, 3A4 and P-gp inducer) and enzalutamide (CYP 2C9, 2C19, 3A4 inducer and P-gp inhibitor), several PK interactions were identified with antithrombotics, which could lead to various clinical events (haemorrhage or thromboembolism). CONCLUSION: Numerous interactions are expected between enzalutamide or apalutamide and antithrombotics, for which management should be deployed on a case-by-case basis. PK and pharmaco-epidemiological studies could shed light on whether or not there are clinically significant events related to DDIs with antithrombotics.

Safety differences across androgen receptor inhibitors in nonmetastatic castration-resistant prostate cancer.

Approval of apalutamide, enzalutamide and darolutamide has transformed the treatment landscape and guideline recommendations for patients with nonmetastatic castration-resistant prostate cancer but now raises the issue of decision-making regarding treatment selection. In this perspective, we discuss the efficacy and safety of these second-generation androgen receptor inhibitors and propose that for patients with nonmetastatic castration-resistant prostate cancer, safety considerations for these treatments are especially important. We examine these considerations in the context of patient and caregiver preferences as well as patient clinical characteristics. We further posit that consideration of treatments' safety profiles should include not only the initial direct impacts from potential treatment-emergent adverse events and drug-drug interaction events, but also the full cascade of potentially avoidable healthcare complications.

Prostate cancer is one of the most common cancers in men. Because male hormones fuel the growth of prostate cancer cells, initial treatments generally focus on reducing these hormones to very low levels. Although these treatments are usually effective in controlling the cancer in the short term, over time, patients often stop responding to them. These patients need more advanced treatments to control their prostate cancer. For patients whose cancer has not spread to other body parts ('nonmetastatic castration-resistant prostate cancer'), more advanced treatment options were unavailable until recently, but during 2018­2019, three novel therapies became available. These new therapies have raised the question of how to choose a particular therapy when deciding on a patient's treatment regimen. Here we contend that patient safety is critical when deciding among these treatments, which are all similarly effective in terms of helping patients to live longer. We review the key differences of each drug's safety profile among these treatments. We assert that treatment selection should consider patients' preferences and clinical characteristics, as the latter can influence the potential for serious harm when treatment-related complications arise. Finally, treatment selection should consider the multiple after-effects that can occur following a treatment-related safety event.

Novel hormonal therapies in the management of advanced prostate cancer: extrapolating Asian findings to Southeast Asia.

There is a paucity of information on the use of novel hormonal agents in Southeast Asian patients. We reviewed the clinical roles of novel hormonal therapy (NHT), namely abiraterone acetate (AA), enzalutamide, apalutamide and darolutamide, in the management of advanced prostate cancer, and data on its use in Asian patients, in order to extrapolate these findings to the Southeast Asian patient population. There are some differences in the molecular features between the NHTs, which influenced their respective permeabilities through the blood-brain barrier. The Asian sub-analyses of the landmark studies of each NHT were limited. The primary endpoints of the Asian sub-analyses generally reflect the efficacy outcomes of the respective landmark study. Hypertension, fatigue, musculoskeletal disorders, rash, and hot flushes were among the common toxicities observed in Asian patients. Real-world data on AA in the Asian setting is favourable, but data is limited for enzalutamide, apalutamide and darolutamide. Based on the sub-analyses and real-world data, the efficacy and safety of NHTs in the Asian patients showed a similar trend to the respective landmark studies. The lack of clinical trials in the Southeast Asian region hampers the ability to make a robust conclusion on any specific efficacy or safety differences that may be present; clinicians must assume that the broader Asian sub-analyses and real-world data reflects Southeast Asian patients' outcomes.

Apalutamide-induced lichenoid reaction in a patient with non-metastatic castrate-resistant prostate cancer.

INTRODUCTION: Apalutamide is an oral selective androgen receptor inhibitor, approved by the FDA for the treatment of patients with non-metastatic, castration-resistant prostate cancer (M0 CRPC) at high risk of developing metastases and for patients with metastatic castration-sensitive prostate (mHSPC) in association with androgen deprivation therapy (ADT). In the registration studies, skin reactions were reported among the most common side effects and as an adverse event of special interest. CASE REPORT: Apalutamide-induced rash includes a wide spectrum of different types of skin reactions, but few cases reports and case series have described this adverse event. Here, we report an M0 CRPC patient who experienced a rare skin adverse event, a lichenoid reaction. MANAGEMENT & OUTCOME: After 4 months of therapy with apalutamide, the patient reported dorsal pricking and dry skin. Lichenoid reaction was confirmed histologically and its correlation to the drug was demonstrated after pursuing a multidisciplinary approach. DISCUSSION: To our knowledge, this is one of the first cases of Apalutamide-related lichenoid reaction and this clinical case showed the relevance of a multidisciplinary management when assessing drug-related adverse events. A broader knowledge of the spectrum of drug-related reactions would allow for a better diagnosis and therapy management by both physicians and patients.

Development and validation of apalutamide-related substances method in solid dosage forms using HPLC.

A related-substances method was developed for the anticancer drug formulation apalutamide 60 mg tablets and validated using a liquid chromatography gradient elution method. All of the impurities and degradants were separated using the Luna Omega 5 µm Polar C18 , (250 × 4.6) mm HPLC column with a 1.0 ml min-1 flow rate. The detection was done at 225 nm by injecting the 10 µl of injection volume, controlling the sample temperature at 10°C and maintaining the column compartment temperature at 30°C. The total run time was 85 min. A 0.01 m disodium phosphate dihydrate pH 4.20 ± 0.05 buffer mixed with acetonitrile in the ratio of 73:27 (v/v) was used as mobile phase A. Mobile phase B consisted of water and acetonitrile in the ratio 30:70 (v/v). The proposed method was validated as per the current regulatory guidelines. The method precisions (RSD) at 100% specification level were 1.41, 1.74, 1.84, and 1.66% for the four impurities. The accuracy results were obtained between 96.0 and 106.3% for the limit of quantitation to the 150% level. The standard and sample solutions stability were established for 44 h at 10°C. The correlation coefficient (r) value was >0.999 for all four impurities, indicating good linearity between the concentration and peak response: 0.9999, 0.9999, 0.9999 and 1.0000. These results show the method's linearity. The three filter compatibility was proved and it was concluded that 0.45 µm Nylon, PTFE and PVDF filters are suitable. The robustness of the method was established by varying the conditions. The method specificity was proved and the forced degradation data reveal the method's stability-indicating nature.