Apalutamide and Goserelin for Androgen Receptor-Positive Salivary Gland Carcinoma: A Phase II Nonrandomized Clinical Trial, YATAGARASU.

PURPOSE: To assess the efficacy and safety of apalutamide plus goserelin for androgen receptor (AR)-positive unresectable or recurrent/metastatic salivary gland carcinoma. PATIENTS AND METHODS: This trial was an open-label, single-arm, multicenter phase II study. Patients with histologically confirmed unresectable or recurrent/metastatic salivary gland carcinoma with AR expression were included. The primary endpoint was the overall response rate (ORR) according to RECIST v1.1 by an independent central radiology review in the first 24 response-evaluable (RE) patients who had been observed at least 24 weeks from study initiation (primary RE patients). The efficacy was to be declared when at least 8 of the 24 primary RE patients responded. RESULTS: A total of 31 patients were enrolled. In the first 24 primary RE patients with a median follow-up of 7.4 months, confirmed ORR by independent central radiology review was 25.0% [6/24 patients; 95% confidence interval, 9.8%-46.7%; P = 0.11 (one-sided)], which did not meet the predefined criteria of efficacy. Clinical benefit rate (ORR + rate of stable disease for at least 24 weeks) and median progression-free survival were 50.0% and 7.4 months, respectively. Both median duration of response and overall survival were not reached. Exploratory analyses showed a better ORR of 54.5% (6/11) in patients with AR positivity ≥70% and no history of prior systemic therapy. Grade 3 or higher treatment-emergent adverse events were reported in 35.5% (11/31), which included skin rash, anemia, leukopenia, and cancer pain. CONCLUSIONS: Although this study did not meet the predefined efficacy criteria, apalutamide plus goserelin showed clinically meaningful efficacy in a subset of patients with AR-positive salivary gland carcinoma and safety consistent with prior experience in prostate cancer.

A retrospective study on the incidence, management and risk factors of skin rash in patients with advanced prostate cancer in Japan.

BACKGROUND: Worldwide, prostate cancer (PC) is the second most diagnosed cancer and the fifth leading cause of cancer death in men. Hormonal therapies, commonly used for PC, are associated with a range of treatment-emergent adverse events (TEAEs). The population from Japan seems to be at higher risk of developing TEAEs of skin rash compared to the overall global population. This study was conducted to get a better insight into the incidence, management, and risk factors for skin rash during active treatment for advanced PC in Japan. METHODS: A retrospective cohort of PC patients was identified and subsequently categorized, into non-metastatic and metastatic castration-resistant prostate cancer patients (nmCRPC and mCRPC), and metastatic castration-naïve prostate cancer patients (mCNPC). The analysis was based on a dataset from the Medical Data Vision (MDV) database. Descriptive statistics were determined, and a multivariate Cox proportional hazards model was used to the associated risk factors for the onset of rash. RESULTS: Overall, 1,738 nmCRPC patients, 630 mCRPC patients, and 454 mCNPC patients were included in this analysis. The median age was 78 years old and similar across the three cohorts. The skin rash incidence was 19.97% for nmCRPC cohort, 28.89% for mCRPC cohort, and 28.85% for mCNPC cohort. The median duration of skin rash ranged from 29 to 42 days. Statistically significant risk factors for developing skin rash included a history of allergy or hypersensitivity (all cohorts), increased age (nmCRPC and mCRPC), a body mass index (BMI) of < 18.5 (nmCRPC and mCRPC), and a PSA level higher than the median (nmCRPC). Skin rash was commonly managed with systemic and topical corticosteroids which ranged from 41.76% to 67.03% for all cohorts. Antihistamines were infrequently used. CONCLUSION: This study provides a better understanding of the real-world incidence, onset, duration, management and risk factors of skin rash in patients on active PC treatment in Japan. It was observed that approximately 20-30% of PC patients experience skin rash. Development of skin rash was associated with previous allergy or hypersensitivity, BMI of < 18.5, increased age and higher PSA levels, and was usually treated with corticosteroids.

Clinical Outcomes of First Subsequent Therapies After Abiraterone Acetate Plus Prednisone for High-Risk Metastatic Castration-Sensitive Prostate Cancer in the LATITUDE Study.

BACKGROUND: Abiraterone acetate plus prednisone with androgen deprivation therapy is a standard treatment option for patients with high-risk metastatic castration-sensitive prostate cancer (mCSPC). However, no data are available on the optimal subsequent treatment option in patients treated with abiraterone acetate plus prednisone for high-risk mCSPC. OBJECTIVE: We aimed to compare the clinical outcomes of subsequent therapy after discontinuation of abiraterone acetate plus prednisone in patients with high-risk mCSPC. METHODS: Overall survival and time to treatment failure from initiation of subsequent therapies were estimated by applying a marginal structural Cox proportional hazards model using inverse probability of treatment weighting with a change of time scale to time on treatment. RESULTS: A total of 217 patients received subsequent therapies: 127 received chemotherapy, 49 received non-chemotherapy, and 41 received other treatments. For overall survival, when adjusted with the marginal structural Cox proportional hazards model using inverse probability of treatment weighting, the hazard ratio was 1.212 (95% confidence interval [CI] 0.742-1.979) for chemotherapy versus non-chemotherapy, 0.534 (95% CI 0.267-1.066) for non-chemotherapy versus other treatments, and 0.635 (95% CI 0.317-1.271) for chemotherapy versus other treatments. For time to treatment failure, the hazard ratio was 1.287 (95% CI 0.832-1.989) for chemotherapy versus non-chemotherapy, 0.785 (95% CI 0.486-1.269) for non-chemotherapy versus other treatments, and 0.898 (95% CI 0.612-1.318) for chemotherapy versus other treatments. CONCLUSIONS: No differences were observed between the treatment effects of chemotherapy and non-chemotherapy in patients with high-risk mCSPC after abiraterone acetate plus prednisone. These findings suggest that life-extending subsequent therapy after abiraterone acetate plus prednisone for mCSPC should be chosen at the physician's discretion and patient's preference. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, NCT01715285, registered 26 October, 2012.

Treatment strategies and outcomes in a long-term registry study of patients with high-risk metastatic hormone-naïve prostate cancer in Japan: An interim analysis of the J-ROCK study.

OBJECTIVE: The prognosis of high-risk metastatic hormone-naïve prostate cancer is poor, and real-world evidence of therapeutic options and sequences is lacking. The J-ROCK study aimed to evaluate the outcomes in a real-world setting in Japan. METHODS: Patients with high-risk metastatic hormone-naïve prostate cancer diagnosed after May 2019 were eligible. Based on their treatment within 3 months after diagnosis, patients were allocated to either cohort 1 (androgen deprivation therapy alone or combined androgen blockade with bicalutamide) or cohort 2 (androgen deprivation therapy with abiraterone acetate+prednisolone, docetaxel, enzalutamide, or apalutamide). RESULTS: In this first interim analysis (cut-off January 2021), 410 patients were enrolled, including 163 patients in cohort 1 and 247 in cohort 2. The median follow-up period was 7.6 (range 0.1-20.5) months. A higher proportion of patients in cohort 2 (42.5%) achieved nadir prostate-specific antigen levels ≤0.2 ng/ml within a year, compared with cohort 1 (22.1%). Prostate-specific antigen-progression-free survival was also more favorable in cohort 2 (adjusted hazard ratio 0.629 [95% confidence interval 0.345-1.147]). CONCLUSIONS: The higher proportion of cohort 2 suggest a paradigm shift has occurred in the real-world treatment of high-risk metastatic hormone-naïve prostate cancer in Japan. Some factors including prostate-specific antigen may affect treatment selection but need further observation. Most patients in cohort 2 received abiraterone acetate+prednisolone. The proportion of patients in cohort 1 receiving combined androgen blockade was lower than previously reported in Japan. This analysis suggest that more intensive therapy tends to prolong prostate-specific antigen-progression-free survival in patients with high-risk metastatic hormone-naïve prostate cancer.

Assessing the correlation between second progression-free survival (PFS2) and overall survival (OS) in advanced prostate cancer patients using medical data vision (MDV) claims database in Japan.

OBJECTIVE: To assess the correlation between PFS2 and OS among patients with advanced prostate cancer (PC) in a real-world setting for Japan. METHODS: This was a retrospective analysis using the Japanese MDV database. Patients with nmCRPC (non-metastatic Castration-Resistant PC), mCRPC (metastatic Castration-Resistant PC), and mCNPC (metastatic Castration-Naïve PC) were identified and their medical records were investigated for PFS2 and death. Association between PFS2 and OS was determined using the Pearson's, Spearman's, Kendall's Tau, and Fleischers' correlation coefficients. RESULTS: A total of 386,484 patients with PC were identified from the database, of which, 1,783 patients with nmCRPC, 630 with mCRPC, and 454 with mCNPC met the predefined eligibility criteria. Significant correlation between PFS2 and OS was observed in patients with nmCRPC (Pearson's r = 0.873; 95% CI: 0.849-0.897, Spearman's r = 0.909; 95% CI: 0.893-0.925; Kendall's Tau r = 0.831; 95% CI: 0.812-0.850, Fleischers' r = 0.682; 95% CI: 0.601-0.764), mCRPC (Pearson's r = 0.812; 95% CI: 0.758-0.865, Spearman's r = 0.895; 95% CI: 0.868-0.923, Kendall's Tau r = 0.789; 95% CI: 0.755-0.823, Fleischers' r= 0.439; 95% CI: 0.334-0.544), and mCNPC (Pearson's r = 0.931; 95% CI: 0.899-0.964, Spearman's r = 0.943; 95% CI: 0.922-0.964, Kendall's Tau r = 0.866; 95% CI: 0.836-0.896, Fleischers' r = 0.756; 95% CI: 0.624-0.888). CONCLUSIONS: The results of this study indicate a significant correlation between PFS2 and OS, which adds additional evidence to the existing literature of using PFS2 as a surrogate endpoint for OS in patients with PC.

Estimation of Overall Survival with Subsequent Treatment Effect by Applying Inverse Probability of Censoring Weighting in the LATITUDE Study.

BACKGROUND: In the LATITUDE study (ClinicalTrials.gov, NCT01715285), compared with placebos, abiraterone acetate plus prednisone (AAP) with androgen deprivation therapy (ADT) provided significant overall survival (OS) benefit in high-risk metastatic castration-sensitive prostate cancer (mCSPC) patients. It is controversial whether survival benefits would remain if all patients in the placebo group subsequently received life-extending therapies. OBJECTIVE: To estimate treatment effect in the case of all patients in the placebo group receiving life-extending subsequent therapies. DESIGN SETTING AND PARTICIPANTS: A post hoc analysis of LATITUDE final-analysis data was carried out (setting and participants have been reported previously). INTERVENTION: AAP or placebos plus ADT. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: We applied the inverse probability of censoring weighting (IPCW) method to represent the situation in which all patients in the placebo group would have received life-extending subsequent therapies. The OS hazard ratio (HR) of AAP versus placebos and associated 95% confidence interval (CI) were estimated using a Cox proportional hazards model. RESULTS AND LIMITATIONS: Of the 581 eligible patients in the placebo group, 237 (40.8%) did not receive life-extending subsequent therapies. From the unadjusted intention-to-treat analysis, the HR for OS for AAP versus placebos was 0.661 (95% CI 0.564-0.775). Using IPCW to adjust for patients in the placebo group without life-extending subsequent therapies, the HR was 0.732 (95% CI 0.604-0.887). A limitation is a lack of proof that the Cox proportional hazards model for the absence of life-extending subsequent therapy is correctly specified for the IPCW method. CONCLUSIONS: Treatment with AAP exerts OS benefit over placebos in high-risk mCSPC patients, regardless of whether life-extending subsequent therapy is given. PATIENT SUMMARY: In a previous study, high-risk metastatic castration-sensitive prostate cancer patients who received abiraterone acetate plus prednisone (AAP) with androgen deprivation therapy generally survived longer than those given placebos. The benefit of adding AAP continues regardless of whether life-extending subsequent therapy is given.

Safety and efficacy of abiraterone acetate plus prednisolone in patients with castration-resistant prostate cancer: a prospective, observational, post-marketing surveillance study.

BACKGROUND: Abiraterone acetate plus prednisolone is approved to treat patients with castration-resistant prostate cancer. This study evaluated the safety and efficacy of abiraterone acetate plus prednisolone in castration-resistant prostate cancer patients with or without previous chemotherapy in a real-world setting in Japan. METHODS: This study was an observational, prospective, post-marketing surveillance. Castration-resistant prostate cancer patients, who initiated abiraterone acetate after its approval in Japan, were enrolled. Data were collected during an observation period of 12 months and a follow-up period of another 12 months. Adverse events and adverse drug reactions were evaluated for safety. Prostate-specific antigen levels and overall survival were evaluated for efficacy. RESULTS: From 141 participating institutions, 497 patients were registered: 492 patients including 180 chemotherapy-naïve, 311 chemotherapy-experienced and one off-label-use patient received abiraterone and were evaluated for safety. Adverse events were observed in 225/492 patients (45.7%), adverse drug reactions in 131/492 patients (26.6%) and serious adverse drug reactions in 61/492 patients (12.4%). The most commonly observed adverse drug reaction was abnormal hepatic function (6.5%), followed by hypokalemia (3.0%) and decreased appetite (2.0%). At week 12, 110/432 patients (25.5%) achieved ≥50% decrease from baseline in prostate-specific antigen, and the proportion was higher in chemotherapy-naïve patients (56/161 patients; 34.8%) compared with chemotherapy-experienced patients (54/271 patients; 19.9%, P < 0.001). Survival rates at 24 months were 68.3% (295/432 patients), 73.9% (119/161 chemotherapy-naïve patients) and 64.9% (176/271 chemotherapy-experienced patients). CONCLUSIONS: This large-scale, real-world, post-marketing surveillance study confirmed the safety and efficacy of abiraterone acetate plus prednisolone in Japanese castration-resistant prostate cancer patients with or without previous chemotherapy.

Correction to: Skin rash following Administration of Apalutamide in Japanese patients with Advanced Prostate Cancer: an integrated analysis of the phase 3 SPARTAN and TITAN studies and a phase 1 open-label study.

An amendment to this paper has been published and can be accessed via the original article.

Skin rash following Administration of Apalutamide in Japanese patients with Advanced Prostate Cancer: an integrated analysis of the phase 3 SPARTAN and TITAN studies and a phase 1 open-label study.

BACKGROUND: A higher incidence of apalutamide-related skin rash has been observed in Japanese patients with prostate cancer (PC). METHODS: This integrated analysis of data of Japanese patients from 2 global Phase 3 studies, SPARTAN ( NCT01946204 ; patients with non-metastatic castration-resistant PC [nmCRPC]) and TITAN ( NCT02489318 ; patients with metastatic castration-sensitive PC [mCSPC]), and the Phase 1 study 56021927PCR1008 ( NCT02162836 ; patients with metastatic CRPC [mCRPC]), assessed clinical risk factors of apalutamide-related skin rash as well as the potential correlation with plasma exposure to apalutamide. Kaplan-Meier method was used for time-to-event analyses. Clinical risk factors for skin rash were assessed using odds ratio. RESULTS: Data from 68 patients (SPARTAN: n = 34, TITAN: n = 28, 56021927PCR1008: n = 6) receiving apalutamide 240 mg orally once-daily were analyzed. Rash (13 [19.1%]) and maculo-papular rash (11 [16.2%]) were the most frequently reported skin rash. All Grade and Grade 3 skin rash occurred in 35 (51.5%) and 10 (14.7%) patients, respectively. Most (85.7%) skin rash occurred within 4 months of apalutamide initiation and resolved in a median time of 1 month following the use of antihistamines, topical or systemic corticosteroids, with/without apalutamide dose interruptions/reductions. Median time-to-remission of first incidence of rash and maximum grade incidence of rash were 1.0 month (IQR: 0.36-1.81) and 1.0 month (IQR: 0.30-2.43), respectively. No significant clinical risk factors for the incidence of skin rash were observed. Areas under the curve (0-24 h) (AUC0-24, ss) at steady-state of plasma apalutamide concentration were numerically slightly higher in patients with skin rash than those without. CONCLUSIONS: No clinical risk factors for rash could be detected. There is a potential correlation between incidence of skin rash and plasma exposure to apalutamide. In general, apalutamide-related skin rash is easily managed, with appropriate treatment with or without dose adjustment. TRIAL REGISTRATION: Retrospective pooled analysis of NCT01946204 , NCT02489318 , and NCT02162836 .

The correlation between metastasis-free survival and overall survival in non-metastatic castration resistant prostate cancer patients from the Medical Data Vision claims database in Japan.

Background and purpose: Several recent randomized controlled trials (RCTs) in non-metastatic castration resistant prostate cancer (nmCRPC) have demonstrated a significant improvement in metastasis-free survival (MFS); however, an improvement in overall survival (OS) is not reported yet. Since the surrogacy of MFS to OS has not been formally investigated in nmCRPC in Japan, this study evaluated the correlation between MFS and OS among a nmCRPC population in Japan. Methods: This is a retrospective longitudinal observational cohort study in patients with nmCRPC using the Japanese Medical Data Vision (MDV) database covering over 20 million patients. A total of 1236 patients with CRPC who had no prior medical history of cancer except prostate cancer and no distant metastasis, and who fulfilled PCWG2 criteria, were identified. Following the identification of nmCRPC, patients' medical records were investigated for subsequent events of metastasis and death. Results: The median follow-up time was 24 months. Median MFS was 28 months (95% CI: 24.0 to 33.0 months) and median OS could not be estimated (95% CI: not estimated). There was a statistically significant correlation between MFS and OS (Pearson's correlation coefficient = 0.62; 95% CI: 0.58-0.65; p < .0001, Spearman's correlation coefficient = 0.62; 95% CI: 0.58-0.65; p < .0001 and Kendall's τ statistic = 0.53; 95% CI: 0.49-0.56; p < .0001). Conclusions: The results of this study indicate a significant correlation between MFS and OS. It may justify the usefulness of MFS as surrogate for OS in nmCRPC.