Search

Purpose: The three-arm, phase III KEYNOTE-361 study did not meet its dual primary endpoints of progression-free survival (PFS) or overall survival (OS) with first-line pembrolizumab plus chemotherapy versus chemotherapy in advanced urothelial carcinoma. This prespecified exploratory analysis assessed the association of tumor mutational burden (TMB) and PD-L1 combined positive score (CPS) with clinical outcomes., Patients and Methods: TMB and PD-L1 CPS were determined via whole-exome sequencing and PD-L1 IHC 22C3 pharmDx, respectively. The association was evaluated in each treatment arm using logistic regression [objective response rate (ORR)] and Cox proportional hazards regression models (PFS and OS); one-sided (pembrolizumab monotherapy; pembrolizumab plus chemotherapy) and two-sided (chemotherapy) nominal P values were calculated. Significance was prespecified at α = 0.05 without multiplicity adjustment. Efficacy was evaluated by prespecified cutoffs of 175 mutations/exome (TMB) and CPS 10 (PD-L1)., Results: Of the 993 treated patients, 820 (82.6%) and 993 (100%) had evaluable TMB and CPS data, respectively. Continuous TMB was positively associated with ORR, PFS, and OS for pembrolizumab monotherapy (one-sided P < 0.001, P < 0.001, and P = 0.007, respectively); PFS and OS for pembrolizumab plus chemotherapy (one-sided P = 0.007 and P = 0.010, respectively); and OS for chemotherapy alone (two-sided P = 0.040). Continuous PD-L1 CPS showed evidence of anticipated association with ORR and PFS for pembrolizumab monotherapy. The subgroup with TMB ≥175 mutations/exome and PD-L1 CPS ≥10 had the highest PFS and OS improvements with pembrolizumab alone or with chemotherapy versus chemotherapy alone., Conclusions: These data suggest that TMB may be predictive of the response to pembrolizumab alone or with chemotherapy in advanced urothelial carcinoma., (©2024 The Authors; Published by the American Association for Cancer Research.)

Background and Objective: The CABASTY study showed that more frequent administration of a lower dose of cabazitaxel (CBZ) reduced toxicity in older men with metastatic castration-resistant prostate cancer (mCRPC), without compromising efficacy. Here, we investigated the impact of a biweekly CBZ schedule on patient-reported pain and health-related quality of life (HRQoL)., Methods: We randomized 196 patients from 25 centers (1:1, stratified by age and G8 score) to the biweekly CBZ16 (CBZ 16 mg/m 2 ) experimental arm or the triweekly CBZ25 (CBZ 25 mg/m 2 ) control arm (CABASTY study, NCT02961257). We assessed pain using the Numeric Pain Rating Scale and HRQoL using the Functional Assessment of Cancer Therapy-Prostate (FACT-P) questionnaire., Key Findings and Limitations: A total of 141 patients were available for a pain and 160 for an HRQoL analysis. Median time to pain progression (stratified hazard ratio [HR]: 1.7, confidence interval [CI]: 0.67-4.22, p = 0.3) and median time to first opiate use (stratified HR: 1.05, CI: 0.44-2.55, p = 0.9) did not differ between arms. We did not see a significant difference in median time to deterioration of FACT-P total score between treatments (stratified HR: 0.88, CI: 0.47-1.7, p = 0.7). Interestingly, the time to onset of several adverse events was significantly longer in the biweekly CBZ16 group., Conclusions and Clinical Implications: HRQoL did not significantly differ between the biweekly CBZ16 and the standard schedule. Additionally, onset of some adverse events was delayed. These results may increase health care providers' confidence in using CBZ in older patients with mCRPC who are denied chemotherapy., Patient Summary: Androgen receptor pathway inhibitors are often preferred to taxane chemotherapy as a treatment of second or subsequent line in older metastatic castration-resistant prostate cancer patients due to more frequent treatment-related toxicities. Here, we showed that quality of life and pain did not differ significantly with an adapted schedule of cabazitaxel (CBZ), compared with the standard regimen. This CBZ schedule could increase eligibility of older patients for chemotherapy., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Background and Objective: Trough abiraterone concentration (ABI C min ) of 8.4 ng/mL has been identified as an appropriate efficacy threshold in patients treated for metastatic castration-resistant prostate cancer (mCRPC). The aim of the phase II OPTIMABI study was to evaluate the efficacy of pharmacokinetics (PK)-guided dose escalation of abiraterone acetate (AA) in underexposed patients with mCRPC with early tumour progression., Methods: This multicentre, non-randomised study consisted of two sequential steps. In step 1, all patients started treatment with 1000 mg of AA once daily. Abiraterone C min was measured 22-26 h after the last dose intake each month during the first 12 weeks of treatment. In step 2, underexposed patients (C min < 8.4 ng/mL) with tumour progression within the first 6 months of treatment were enrolled and received AA 1000 mg twice daily. The primary endpoint was the rate of non-progression at 12 weeks after the dose doubling. During step 1, adherence to ABI treatment was assessed using the Girerd self-reported questionnaire. A post-hoc analysis of pharmacokinetic (PK) data was conducted using Bayesian estimation of C min from samples collected outside the sampling guidelines (22-26 h)., Results: In the intention-to-treat analysis (ITT), 81 patients were included in step 1. In all, 21 (26%) patients were underexposed in step 1, and 8 of them (38%) experienced tumour progression within the first 6 months. A total of 71 patients (88%) completed the Girerd self-reported questionnaire. Of the patients, 62% had a score of 0, and 38% had a score of 1 or 2 (minimal compliance failure), without a significant difference in mean ABI C min in the two groups. Four patients were enrolled in step 2, and all reached the exposure target (C min > 8.4 ng/mL) after doubling the dose, but none met the primary endpoint. In the post-hoc analysis of PK data, 32 patients (39%) were underexposed, and ABI C min was independently associated with worse progression-free survival [hazard ratio (HR) 2.50, 95% confidence interval (CI) 1.07-5.81; p = 0.03], in contrast to the ITT analysis., Conclusion: The ITT and per-protocol analyses showed no statistical association between ABI underexposure and an increased risk of early tumour progression in patients with mCRPC, while the Bayesian estimator showed an association. However, other strategies than dose escalation at the time of progression need to be evaluated. Treatment adherence appeared to be uniformly good in the present study. Finally, the use of a Bayesian approach to recover samples collected outside the predefined blood collection time window could benefit the conduct of clinical trials based on drug monitoring. OPTIMABI trial is registered as National Clinical Trial number NCT03458247, with the EudraCT number 2017-000560-15)., (© 2024. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Background: Reducing nivolumab dose intensity could increase patients' life quality and decrease the financial burden while maintaining efficacy. The aims of this study were to develop a population PK model of nivolumab based on data from unselected metastatic cancer patients and to simulate extended-interval regimens allowing to maintain minimal effective plasma concentrations (MEPC)., Methods: Concentration-time data (992 plasma nivolumab concentrations, 364 patients) were modeled using a two-compartment model with linear elimination clearance in Monolix software. Extended-interval regimens allowing to maintain steady-state trough concentrations (C min,ss ) above the MEPC of 2.5 mg/L or 1.5 mg/L in >90% of patients were simulated., Results: Increasing 3-times the dosing interval from 240 mg every two weeks (Q2W) to Q6W and 2-times from 480 mg Q4W to Q8W resulted in C min,ss above 2.5 mg/L in 95.8% and 95.4% of patients, respectively. 240 mg Q8W and 480 mg Q10W resulted in C min,ss above 1.5 mg/L in 91.0% and 91.8% of patients, respectively. Selection of a 240 mg Q6W regimen would decrease by 3-fold the annual treatment costs compared to standard regimen of 240 mg Q2W (from 78,744€ to 26,248€ in France)., Conclusions: Clinical trials are warranted to confirm the non-inferiority of extended-interval compared to standard regimen., (© 2024. The Author(s), under exclusive licence to Springer Nature Limited.)

Background: Interindividual pharmacokinetic variability may influence the clinical benefit or toxicity of cabozantinib in metastatic renal cell carcinoma (mRCC). We aimed to investigate the exposure-toxicity and exposure-response relationship of cabozantinib in unselected mRCC patients treated in routine care., Methods: This ambispective multicenter study enrolled consecutive patients receiving cabozantinib in monotherapy. Steady-state trough concentration (Cmin,ss) within the first 3 months after treatment initiation was used for the PK/PD analysis with dose-limiting toxicity (DLT) and survival outcomes. Logistic regression and Cox proportional-hazards models were used to identify the risk factors of DLT and inefficacy in patients, respectively., Results: Seventy-eight mRCC patients were eligible for the statistical analysis. Fifty-two patients (67%) experienced DLT with a median onset of 2.1 months (95%CI 0.7-8.2). In multivariate analysis, Cmin,ss was identified as an independent risk factor of DLT (OR 1.46, 95%CI [1.04-2.04]; p = 0.029). PFS and OS were not statistically associated with the starting dose (p = 0.81 and p = 0.98, respectively). In the multivariate analysis of PFS, Cmin, ss > 336 ng/mL resulted in a hazard ratio of 0.28 (95%CI, 0.10-0.77, p = 0.014). By contrast, Cmin, ss > 336 ng/mL was not statistically associated with longer OS., Conclusion: Early plasma drug monitoring may be useful to optimise cabozantinib treatment in mRCC patients treated in monotherapy, especially in frail patients starting at a lower than standard dose., (© 2024. The Author(s), under exclusive licence to Springer Nature Limited.)