Androgen deprivation therapy (ADT) is a mainstay initial treatment for advanced hormone-sensitive prostate cancer (HSPC), but disease progression to castration-resistant prostate cancer (CRPC) ...invariably occurs when patients do not succumb to another disease or comorbidity. Recognition that the androgen receptor (AR) axis continues to drive disease progression has led to the development of several AR-directed approved agents, including abiraterone acetate and enzalutamide. An investigational agent, darolutamide (ODM-201, BAY-1841788), has completed early-phase clinical trials, and two global phase III trials are currently accruing patients. Areas covered: The unmet clinical need, pharmacokinetics, preclinical development, and clinical efficacy and safety of darolutamide for the treatment of advanced prostate cancer are reviewed. The design of two ongoing phase III trials (ARAMIS and ARASENS) of darolutamide in men with non-metastatic CRPC and metastatic HSPC, respectively, are also discussed. Expert opinion: Darolutamide is an oral, investigational, high-affinity AR antagonist which has activity against known AR mutants that confer resistance to other second-generation antiandrogens, has minimal blood-brain barrier penetration, and does not significantly increase serum testosterone. These features may offer potential advantages over the second-generation antiandrogens. In the phase I/II ARADES trial, darolutamide demonstrated promising antitumor activity and a favorable safety profile in men with metastatic CRPC.
Summary Background Enzalutamide is an oral androgen-receptor inhibitor that has been shown to improve survival in two placebo-controlled phase 3 trials, and is approved for patients with metastatic ...castration-resistant prostate cancer. The objective of the TERRAIN study was to compare the efficacy and safety of enzalutamide with bicalutamide in patients with metastatic castration-resistant prostate cancer. Methods TERRAIN was a double-blind, randomised phase 2 study, that recruited asymptomatic or minimally symptomatic men with prostate cancer progression on androgen-deprivation therapy (ADT) from academic, community, and private health-care provision sites across North America and Europe. Eligible patients were randomly assigned (1:1) via an interactive voice response system to receive enzalutamide 160 mg/day or bicalutamide 50 mg/day, both taken orally, in addition to ADT, until disease progression. Patients were stratified by a permutated block method (block size of four), by whether bilateral orchiectomy or receipt of luteinising hormone-releasing hormone agonist or antagonist therapy started before or after the diagnosis of metastases, and by study site. Participants, investigators, and those assessing outcomes were masked to group assignment. The primary endpoint was progression-free survival, analysed in all randomised patients. Safety outcomes were analysed in all patients who received at least one dose of study drug. The open-label period of the trial is in progress, wherein patients still on treatment at the end of the double-blind treatment period were offered open-label enzalutamide at the discretion of the patient and study investigator. This trial is registered with ClinicalTrials.gov , number NCT01288911. Findings Between March 22, 2011, and July 11, 2013, 375 patients were randomly assigned, 184 to enzalutamide and 191 to bicalutamide. 126 (68%) and 168 (88%) patients, respectively, discontinued their assigned treatment before study end, mainly due to progressive disease. Median follow-up time was 20·0 months (IQR 15·0–25·6) in the enzalutamide group and 16·7 months (10·2–21·9) in the bicalutamide group. Patients in the enzalutamide group had significantly improved median progression-free survival (15·7 months 95% CI 11·5–19·4) compared with patients in the bicalutamide group (5·8 months 4·8–8·1; hazard ratio 0·44 95% CI 0·34–0·57; p<0·0001). Of the most common adverse events, those occurring more frequently with enzalutamide than with bicalutamide were fatigue (51 28% of 183 patients in the enzalutamide group vs 38 20% of 189 in the bicalutamide group), back pain (35 19% vs 34 18%), and hot flush (27 15% vs 21 11%); those occurring more frequently with bicalutamide were nausea (26 14% vs 33 17%), constipation (23 13% vs 25 13%), and arthralgia (18 10% vs 30 16%). The most common grade 3 or worse adverse events in the enzalutamide or bicalutamide treatment groups, respectively, were hypertension (13 7% vs eight 4%), hydronephrosis (three 2% vs seven 4%), back pain (five 3% vs three 2%), pathological fracture (five 3% vs two 1%), dyspnoea (four 2% vs one 1%), bone pain (one 1% vs four 2%), congestive cardiac failure (four 2% vs two 1%), myocardial infarction (five 3% vs none), and anaemia (four 2% vs none). Serious adverse events were reported by 57 (31%) of 183 patients and 44 (23%) of 189 patients in the enzalutamide and bicalutamide groups, respectively. One of the nine deaths in the enzalutamide group was thought to be possibly related to treatment (due to systemic inflammatory response syndrome) compared with none of the three deaths in the bicalutamide group. Interpretation The data from the TERRAIN trial support the use of enzalutamide rather than bicalutamide in patients with asymptomatic or mildly symptomatic metastatic castration-resistant prostate cancer. Funding Astellas Pharma, Inc and Medivation, Inc.
Preliminary trial results showed that enzalutamide significantly improved metastasis-free survival among men who had nonmetastatic, castration-resistant prostate cancer and rapidly increasing ...prostate-specific antigen (PSA) levels while taking androgen-deprivation therapy. Results from the final analysis of overall survival have not yet been reported.
In this double-blind, phase 3 trial, men with nonmetastatic, castration-resistant prostate cancer (defined on the basis of conventional imaging and a PSA doubling time of ≤10 months) who were continuing to receive androgen-deprivation therapy were randomly assigned (in a 2:1 ratio) to receive enzalutamide at a dose of 160 mg or placebo once daily. Overall survival was assessed with a group sequential testing procedure and an O'Brien-Fleming-type alpha-spending function.
As of October 15, 2019, a total of 288 of 933 patients (31%) in the enzalutamide group and 178 of 468 (38%) in the placebo group had died. Median overall survival was 67.0 months (95% confidence interval CI, 64.0 to not reached) in the enzalutamide group and 56.3 months (95% CI, 54.4 to 63.0) in the placebo group (hazard ratio for death, 0.73; 95% CI, 0.61 to 0.89; P = 0.001). The exposure-adjusted rate of adverse events of grade 3 or higher was 17 per 100 patient-years in the enzalutamide group and 20 per 100 patient-years in the placebo group. Adverse events in the enzalutamide group were consistent with those previously reported for enzalutamide; the most frequently reported events were fatigue and musculoskeletal events.
Enzalutamide plus androgen-deprivation therapy resulted in longer median overall survival than placebo plus androgen-deprivation therapy among men with nonmetastatic, castration-resistant prostate cancer and a rapidly rising PSA level. The risk of death associated with enzalutamide was 27% lower than with placebo. Adverse events were consistent with the established safety profile of enzalutamide. (Funded by Pfizer and Astellas Pharma; PROSPER ClinicalTrials.gov number, NCT02003924.).
Objectives
To provide a practical review of immune‐related adverse events (irAEs) that may be encountered in uro‐oncology patients.
Patients and Methods
We conducted a literature review of studies ...reporting irAEs including articles published through September 2023 for uro‐oncology patients and the potential relevancy for the practicing urologist.
Results
Immunotherapy has revolutionised cancer treatment, extending its impact to urological malignancies including for patients with urothelial, kidney, and prostate cancers. Immuno‐oncology (IO) compounds have achieved measurable and durable responses in these cancers. Urologists, choosing to administer or co‐manage IO patient care, should be prepared to understand, evaluate, and treat irAEs. This review discusses the spectrum of irAEs that can be encountered. Ongoing trials are exploring the use of immunotherapy at earlier stages of uro‐oncological diseases, thus underscoring the evolving landscape of urological cancer treatment. Paradoxically, some data suggests that the occurrence of irAEs is associated with improved oncological outcomes.
Conclusions
Immune‐related AEs, while manageable, may be life‐threatening and require lifelong therapy. A thorough understanding of AEs and toxicity of a novel drug class is imperative.
Radium-223 dichloride (radium-223) is an important therapeutic option for the treatment of patients with castration-resistant prostate cancer, symptomatic bone metastases, and no visceral disease. ...The unique mechanism of action of this first-in-class alpha-emitting radiopharmaceutical underlies its favorable safety profile and low incidence of myelosuppression. In the pivotal phase 3 ALpharadin in SYMptomatic Prostate CAncer Patients study, radium-223 reduced the risk of death by 30% and prolonged time to first symptomatic skeletal event by 5.8 months. This article summarizes current guidelines and clinical studies that led to the approval of radium-223 as an overall survival therapy, and discusses the urologist's perspective on using radium-223 in clinical practice.
Enzalutamide, a potent androgen-receptor inhibitor, has demonstrated significant benefits in metastatic and nonmetastatic castration-resistant prostate cancer. We evaluated the efficacy and safety of ...enzalutamide in metastatic hormone-sensitive prostate cancer (mHSPC).
ARCHES (ClinicalTrials.gov identifier: NCT02677896) is a multinational, double-blind, phase III trial, wherein 1,150 men with mHSPC were randomly assigned 1:1 to enzalutamide (160 mg/day) or placebo, plus androgen deprivation therapy (ADT), stratified by disease volume and prior docetaxel chemotherapy. The primary end point was radiographic progression-free survival.
As of October 14, 2018, the risk of radiographic progression or death was significantly reduced with enzalutamide plus ADT versus placebo plus ADT (hazard ratio, 0.39; 95% CI, 0.30 to 0.50;
< .001; median not reached
19.0 months). Similar significant improvements in radiographic progression-free survival were reported in prespecified subgroups on the basis of disease volume and prior docetaxel therapy. Enzalutamide plus ADT significantly reduced the risk of prostate-specific antigen progression, initiation of new antineoplastic therapy, first symptomatic skeletal event, castration resistance, and reduced risk of pain progression. More men achieved an undetectable prostate-specific antigen level and/or an objective response with enzalutamide plus ADT (
< .001). Patients in both treatment groups reported a high baseline level of quality of life, which was maintained over time. Grade 3 or greater adverse events were reported in 24.3% of patients who received enzalutamide plus ADT versus 25.6% of patients who received placebo plus ADT, with no unexpected adverse events.
Enzalutamide with ADT significantly reduced the risk of metastatic progression or death over time versus placebo plus ADT in men with mHSPC, including those with low-volume disease and/or prior docetaxel, with a safety analysis that seems consistent with the safety profile of enzalutamide in previous clinical trials in castration-resistant prostate cancer.
Injectable luteinizing hormone-releasing hormone agonists (e.g., leuprolide) are the standard agents for achieving androgen deprivation for prostate cancer despite the initial testosterone surge and ...delay in therapeutic effect. The efficacy and safety of relugolix, an oral gonadotropin-releasing hormone antagonist, as compared with those of leuprolide are not known.
In this phase 3 trial, we randomly assigned patients with advanced prostate cancer, in a 2:1 ratio, to receive relugolix (120 mg orally once daily) or leuprolide (injections every 3 months) for 48 weeks. The primary end point was sustained testosterone suppression to castrate levels (<50 ng per deciliter) through 48 weeks. Secondary end points included noninferiority with respect to the primary end point, castrate levels of testosterone on day 4, and profound castrate levels (<20 ng per deciliter) on day 15. Testosterone recovery was evaluated in a subgroup of patients.
A total of 622 patients received relugolix and 308 received leuprolide. Of men who received relugolix, 96.7% (95% confidence interval CI, 94.9 to 97.9) maintained castration through 48 weeks, as compared with 88.8% (95% CI, 84.6 to 91.8) of men receiving leuprolide. The difference of 7.9 percentage points (95% CI, 4.1 to 11.8) showed noninferiority and superiority of relugolix (P<0.001 for superiority). All other key secondary end points showed superiority of relugolix over leuprolide (P<0.001). The percentage of patients with castrate levels of testosterone on day 4 was 56.0% with relugolix and 0% with leuprolide. In the subgroup of 184 patients followed for testosterone recovery, the mean testosterone levels 90 days after treatment discontinuation were 288.4 ng per deciliter in the relugolix group and 58.6 ng per deciliter in the leuprolide group. Among all the patients, the incidence of major adverse cardiovascular events was 2.9% in the relugolix group and 6.2% in the leuprolide group (hazard ratio, 0.46; 95% CI, 0.24 to 0.88).
In this trial involving men with advanced prostate cancer, relugolix achieved rapid, sustained suppression of testosterone levels that was superior to that with leuprolide, with a 54% lower risk of major adverse cardiovascular events. (Funded by Myovant Sciences; HERO ClinicalTrials.gov number, NCT03085095.).
Co-inhibition of poly(ADP-ribose) polymerase (PARP) and androgen receptor activity might result in antitumour efficacy irrespective of alterations in DNA damage repair genes involved in homologous ...recombination repair (HRR). We aimed to compare the efficacy and safety of talazoparib (a PARP inhibitor) plus enzalutamide (an androgen receptor blocker) versus enzalutamide alone in patients with metastatic castration-resistant prostate cancer (mCRPC).
TALAPRO-2 is a randomised, double-blind, phase 3 trial of talazoparib plus enzalutamide versus placebo plus enzalutamide as first-line therapy in men (age ≥18 years ≥20 years in Japan) with asymptomatic or mildly symptomatic mCRPC receiving ongoing androgen deprivation therapy. Patients were enrolled from 223 hospitals, cancer centres, and medical centres in 26 countries in North America, Europe, Israel, South America, South Africa, and the Asia-Pacific region. Patients were prospectively assessed for HRR gene alterations in tumour tissue and randomly assigned (1:1) to talazoparib 0·5 mg or placebo, plus enzalutamide 160 mg, administered orally once daily. Randomisation was stratified by HRR gene alteration status (deficient vs non-deficient or unknown) and previous treatment with life-prolonging therapy (docetaxel or abiraterone, or both: yes vs no) in the castration-sensitive setting. The sponsor, patients, and investigators were masked to talazoparib or placebo, while enzalutamide was open-label. The primary endpoint was radiographic progression-free survival (rPFS) by blinded independent central review, evaluated in the intention-to-treat population. Safety was evaluated in all patients who received at least one dose of study drug. This study is registered with ClinicalTrials.gov (NCT03395197) and is ongoing.
Between Jan 7, 2019, and Sept 17, 2020, 805 patients were enrolled and randomly assigned (402 to the talazoparib group and 403 to the placebo group). Median follow-up for rPFS was 24·9 months (IQR 21·9–30·2) for the talazoparib group and 24·6 months (14·4–30·2) for the placebo group. At the planned primary analysis, median rPFS was not reached (95% CI 27·5 months–not reached) for talazoparib plus enzalutamide and 21·9 months (16·6–25·1) for placebo plus enzalutamide (hazard ratio 0·63; 95% CI 0·51–0·78; p<0·0001). In the talazoparib group, the most common treatment-emergent adverse events were anaemia, neutropenia, and fatigue; the most common grade 3–4 event was anaemia (185 46% of 398 patients), which improved after dose reduction, and only 33 (8%) of 398 patients discontinued talazoparib due to anaemia. Treatment-related deaths occurred in no patients in the talazoparib group and two patients (<1%) in the placebo group.
Talazoparib plus enzalutamide resulted in clinically meaningful and statistically significant improvement in rPFS versus standard of care enzalutamide as first-line treatment for patients with mCRPC. Final overall survival data and additional long-term safety follow-up will further clarify the clinical benefit of the treatment combination in patients with and without tumour HRR gene alterations.
Pfizer.
Purpose The availability of newly approved treatment options for metastatic castration resistant prostate cancer is not matched with conclusive data on optimal sequencing strategies and resistance ...patterns. A comprehensive review of efficacy and safety data for new agents and current knowledge regarding treatment sequencing would enable treating physicians to make rational drug selections in patients with metastatic castration resistant prostate cancer. Materials and Methods We searched MEDLINE® and relevant congresses for data on cabazitaxel, docetaxel,223 radium dichloride, abiraterone, enzalutamide and sipuleucel-T, focusing on sequencing strategies, resistance mechanisms and biomarkers of response. Results Abiraterone and enzalutamide target the androgen axis with different mechanisms of action. Abiraterone blocks cytochrome P450 17, inhibiting androgen synthesis, whereas enzalutamide inhibits androgen receptor, reducing nuclear translocation of the androgen receptor complex and subsequent DNA binding. Both agents provide improved overall survival in patients with metastatic castration resistant prostate cancer who received prior docetaxel treatment and in those who are chemotherapy naïve. Cabazitaxel provides improved overall survival in patients with metastatic castration resistant prostate cancer with prior docetaxel therapy. Sipuleucel-T provides improved overall survival in asymptomatic patients and223 radium provides improved overall survival in chemotherapy naïve and chemotherapy treated patients with symptomatic bone metastases. Selecting the correct treatment with metastatic castration resistant prostate cancer is complex as no head-to-head trials have been done and comparison between existing trials is difficult due to differences in study populations and a lack of validated biomarkers. Factors to consider include prior therapy, symptom burden, metastasis type, performance status, comorbidities, adverse event profiles and patient preference. Another consideration is treatment sequence since some agents affect responses to subsequent choices. For example, resistance to abiraterone or enzalutamide may result in limited responses to subsequent androgen targeted agents. Identifying factors predictive of resistance is an area of ongoing research with androgen receptor variants representing a good candidate. Prognostic factors for survival are also likely to be useful and are currently being studied. Conclusions New therapies for metastatic castration resistant prostate cancer have brought new challenges with regard to treatment selection and sequencing. While hormonal agents provide good therapeutic responses, resistance may be intrinsic without prior drug exposure. Identifying predictors of response and relevant biomarkers will allow therapies to be more precisely tailored to individual patient profiles.
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