The use of adaptive population selection designs has become widespread in response to the emergence of numerous targeted therapies. Such designs provide an opportunity to stop the recruitment of patients in a population in midcourse when this population does not benefit from the treatment being tested. Several types of designs have been developed in different settings; however, the procedures for setting thresholds for an interim decision have not yet been established. Therefore, in this article, we propose a novel, simple utility-based approach to guide the construction of an interim decision rule for an adaptive population selection design using survival endpoints. This approach is applicable when there is an available biomarker prior to designing a clinical trial. Our simulation studies, which assumed that only a prespecified population will benefit from a targeted therapy, indicated that the proposed approach assists in setting optimal thresholds for selecting an appropriate population at the interim analysis.
Precision medicine is an emerging approach for disease treatment and prevention that accounts for individual variability in genes, environment, and lifestyle. Cancer is a genomic disease; therefore, the dose-efficacy and dose-toxicity relationships for molecularly targeted agents in cancer most likely differ, based on the genomic mutation pattern. The individualized optimal dose - the maximal efficacious dose with a clinically acceptable safety profile - may vary depending on the genomic mutation patterns and should be determined prior to the use of these agents in precision medicine. In addition, genes that influence the individualized optimal doses should be identified in early-phase development. In this study, we propose a novel dose-finding approach to identify the individualized optimal dose for molecularly targeted agents in phase I cancer trials. Individualized optimal dose determination and gene selection were conducted simultaneously based on L-1 and L-2 penalized regression. Similar to most reported dose-finding approaches, this study considers non-monotonic patterns for dose-efficacy and dose-toxicity relationships, as well as correlations between efficacy and toxicity outcomes based on multinomial distribution. Our dose-finding algorithm is based on the predictive probability calculated with an estimated penalized regression model. We compare the operating characteristics between the proposed and existing methods by simulation studies under various scenarios.
Objectives: We evaluated long-term control of rheumatoid arthritis (RA) in Japanese paid workers (PWs) and house workers (HWs) treated with subcutaneous tocilizumab (TCZ-SC) and explored factors affecting response to TCZ-SC regarding work productivity. Methods: This study collected data from patients with RA in the TCZ-SC +/- conventional synthetic disease-modifying antirheumatic drugs group. Factors affecting the response to tocilizumab regarding work productivity were explored using logistic regression. Differences in quality-adjusted life years (QALYs) between with/without response were analysed by a linear regression. Results: Data were analysed for 357/360 patients. Patients with a >= 75% improvement in activity impairment (AI) were considered responders. EuroQol-5 Dimension (EQ-5D), six-item Kessler psychological distress scale score (K6), Health Assessment Questionnaire Disability Index (HAQ-DI), and the patient's disease global health by visual analogue scale were significant contributors to TCZ-SC response based on improvements in AI. Work Functioning Impairment Scale, presenteeism, EQ-5D, K6, and HAQ-DI significantly contributed to the improvement of overall work impairment in PWs. Shorter disease duration also was related to TCZ-SC response based on AI improvements. Responders had significantly larger mean QALYs than non-responders (difference = 0.2614; p < .001). Conclusions: These real-world clinical data support long-term work productivity control with TCZ-SC for biologic-naive HWs and PWs with RA.
In recent placebo-controlled randomized phase 3 oncology trials, evaluation of overall survival with frequent crossover is crucial for regulatory and pricing decisions. The problem is that an intention-to-treat based analysis causes a substantial loss of power to detect causal survival effect without crossover, and performance of existing methods is not satisfactory. In this article, our aims were to evaluate properties of the existing and a proposed Bayesian power prior method where data from an external trial is available. Simulation results suggested that proposed method was the most powerful under typical scenarios where patients with better prognosis are likely to crossover.
Background Up to 6-months oxaliplatin-containing regimen is now widely accepted as a standard adjuvant chemotherapy for stage III colorectal cancer (CRC). However, oral fluoropyrimidine monotherapy is used for some part of patients, especially in Asian countries including Japan, and its optimal duration is yet to be fully investigated. Methods A total of 1306 patients with curatively-resected stage III CRC were randomly assigned to receive capecitabine (2500 mg/m 2 /day) for 14 out of 21 days for 6 ( n = 654) or 12 ( n = 650) months. The primary endpoint was disease-free survival (DFS), and the secondary endpoints were relapse-free survival (RFS), overall survival (OS), and adverse events. Results The 3- and 5-year DFS were 70.0% and 65.3% in the 6M group and 75.3% and 68.7% in the 12M group, respectively ( p = 0.0549, HR = 0.858, 90% CI: 0.732–1.004). The 5-year RFS was 69.3% and 74.1% in the 6M and 12M groups, respectively ( p = 0.0143, HR = 0.796, 90% CI: 0.670–0.945). The 5-year OS was 83.2% and 87.6%, respectively ( p = 0.0124, HR = 0.727, 90% CI: 0.575–0.919). The incidence of overall grade 3–4 adverse events was almost comparable in both groups. Conclusions Although 12-month adjuvant capecitabine did not demonstrate superior DFS to that of 6-month, the observed better RFS and OS in the 12-month treatment period could be of value in selected cases.
Background: The paraaortic lymph-node (PALN) is a relatively uncommon metastasis as a first site of recurrence following colorectal cancer (CRC) surgery. Localized and resectable PALN recurrence has the potential of long-term survival by curative resection. We evaluated the risk factors for the recurrence of PALN following curative surgery in patients with CRC in a pooled analysis of two large randomised control studies.
Recommended phase 2 doses for some drugs may differ according to a patient's clinical or genetic characteristics. We develop a new method that determines the individualized optimal dose according to patterns of patient covariates and selects the covariates that are associated with efficacy and toxicity in early phase trials for evaluating multiple patient covariates of interest. To address the difficulty of high dimensional estimation of model parameters with a limited sample size, we propose the use of the Bayesian least absolute shrinkage and selection operator, which is a penalized regression approach. We demonstrate the potential utility of this proposed method through various simulation studies.
Phase I trials investigate the drugs used on humans for the first time. In cancer treatment, drug safety is examined based on the toxicity. Herein, we propose a dose-finding method for oncological phase I drug combinations with delayed toxicity. The toxicity data of the patients who do not complete the follow-up period and do not experience toxicity are considered missing data. We use data augmentation to impute missing data while modeling the time required to experience toxicity using a hazard function, modeled using a gamma process. Simulation results demonstrate that the proposed method shortens trial durations without affecting performance.
Recommended phase 2 doses for some drugs may differ according to a patient's clinical or genetic characteristics. We develop a new method that determines the individualized optimal dose according to patterns of patient covariates and selects the covariates that are associated with efficacy and toxicity in early phase trials for evaluating multiple patient covariates of interest. To address the difficulty of high dimensional estimation of model parameters with a limited sample size, we propose the use of the Bayesian least absolute shrinkage and selection operator, which is a penalized regression approach. We demonstrate the potential utility of this proposed method through various simulation studies.
BACKGROUND: Most previous reports to analyze risk factors for peritoneal recurrence in patients with colon cancer have been observational studies of a population-based cohort. OBJECTIVE: This study aimed to determine the risk factors for peritoneal recurrence in patients with stage II to III colon cancer who underwent curative resection. DESIGN: This was a pooled analysis using a combined database obtained from 3 large phase III randomized trials (N = 3714). SETTINGS: Individual patient data were collected from the Japanese Foundation for Multidisciplinary Treatment of Cancer clinical trials 7, 15, and 33, which evaluated the benefits of postoperative 5-fluorouracil-based adjuvant therapies in patients with locally advanced colorectal cancer. PATIENTS: We included patients who had stage II to III colon cancer and underwent curative resection with over D2 lymph node dissection. MAIN OUTCOME MEASURES: Main outcomes measured were risk factors for peritoneal recurrence without other organ metastasis after curative surgery. RESULTS: Peritoneal recurrence occurred in 2.3% (86/3714) of all patients undergoing curative resection. Mean duration from operation to peritoneal recurrence was 17.010.3 months. Of these patients with peritoneal recurrence, 29 patients (34%) had recurrence in 1 other organ. Multivariate analysis showed that age (60 y: HR = 0.531; p = 0.0182), pathological T4 (HR = 3.802; p < 0.0001), lymph node involvement (HR = 3.491; p = 0.0002), and lymphadenectomy (D2: HR = 1.801; p = 0.0356) were independent predictors of peritoneal recurrence. The overall survival was lower in patients who developed peritoneal recurrence than in those with other recurrence (HR = 1.594; p = 0.002). LIMITATIONS: The regimens of adjuvant chemotherapy were limited to oral 5-fluorouracil. CONCLUSIONS: Our findings clarified the risk factors for peritoneal recurrence in patients who underwent curative resection for colon cancer. See Video Abstract at http://links.lww.com/DCR/A609.
BACKGROUND: Although colorectal cancer comprises several histological subtypes, the influences of histological subtypes on disease progression and treatment responses remain controversial. OBJECTIVE: We sought to evaluate the prognostic relevance of mucinous and poorly differentiated histological subtypes of colorectal cancer by the propensity score weighting analysis of prospectively collected data from multi-institute phase III trials. DESIGN: Independent patient data analysis of a pooled database from 3 phase III trials was performed. SETTINGS: An integrated database of 3 multicenter prospective clinical trials (the Japanese Foundation for Multidisciplinary Treatment of Cancer 7, 15, and 33) was the source of study data. INTERVENTIONS: Surgery alone or postoperative adjuvant chemotherapy was offered in patients with resectable colorectal cancer. MAIN OUTCOME MEASURES: To balance essential variables more strictly for the comparison analyses, propensity score weighting was conducted with the use of a multinomial logistic regression model. We evaluated the clinical signatures of mucinous and poorly differentiated subtypes with regard to postoperative survival, recurrence, and chemosensitivity. RESULTS: Of 5489 patients, 136 (2.5%) and 155 (2.8%) were pathologically diagnosed with poorly differentiated and mucinous subtypes. The poorly differentiated subtypes were associated with a poorer prognosis than the “others” group (HR, 1.69; 95% CI, 1.00–2.87; p = 0.051), particularly in the patient subgroup of adjuvant chemotherapy (HR, 2.16). Although the mucinous subtype had a marginal prognostic impact among patients with stage I to III colorectal cancer (HR, 1.33; 95% CI, 0.90–1.96), it was found to be an independent prognostic factor in the subpopulation of patients with stage II disease, being associated with a higher prevalence of peritoneal recurrence. LIMITATIONS: The treatment regimens of postoperative chemotherapy are now somewhat outdated. CONCLUSIONS: Both mucinous and poorly differentiated subtypes have distinct clinical characteristics. Patients with the mucinous subtype require special attention during follow-up, even for stage II disease, because of the risk of peritoneal or local recurrence. See Video Abstract at http://links.lww.com/DCR/A531.
Following the onset of rheumatoid arthritis (RA), patients experience a functional decline caused by various joint symptoms which affects their activities of daily living and can lead to reduced work productivity. We evaluated the effect of a 52-week treatment with tocilizumab by subcutaneous injection (TCZ-SC) among biologic-naive Japanese house workers (HWs) and paid workers (PWs) with RA in a real-world clinical practice.
In phase I/II anticancer drug-combination trials, trial design to evaluate toxicity and efficacy has been studied by dividing the trial into 2 stages, followed by seamless execution of the 2 stages. In the first stage, admissible dose combinations in toxicity are identified, followed by patient assignment among the identified admissible dose combinations using adaptive randomization in the second stage. When patients are assigned using adaptive randomization, it is desirable to determine a more appropriate dose combination by taking into consideration both drug efficacy and toxicity; however, during the course of this determination and evaluation of toxicity and efficacy, there remains a concern that the trial duration might be prolonged. Therefore, we proposed a trial design to assign patients adaptively to more appropriate dose combinations in both toxicity and efficacy and to shorten trial duration without compromising trial performance. When selecting the dose combination for subsequent cohorts, unobserved data are treated as missing data, which are imputed using a data augmentation algorithm involving a gamma process. Probabilities associated with toxicity and efficacy are estimated applying a Bayesian hierarchical model to the imputed data, thereby allowing more patients to be assigned more appropriate dose combinations in both toxicity and efficacy through adaptive randomization. Results of simulation studies suggested that the proposed approach shortened trial duration without significantly compromising the performance of the trial as compared with existing approaches. We believe that the proposed approach will expedite drug development time and reduce costs associated with clinical development.
In Phase I/II trials for a combination therapy of two agents, we ideally want to explore as many dose combinations as possible with limited sample size in Phase I and to reduce the number of untried dose combinations before moving to Phase II. Efficient collection of toxicity data in Phase I would eventually improve the accuracy of optimal dose combination identification in Phase II. In this paper, we develop a novel dose-finding method based on efficacy and toxicity outcomes for two-agent combination Phase I/II trials. We propose a "zone-finding stage" that determines the most admissible toxicity zone on the dose combination matrix and subsequently select the dose combination allocated to the next patient from that zone in Phase I. Upon completion of this zone-finding stage, we allocate the next patient to the dose combination determined by adaptive randomization of the admissible toxicity and efficacy dose combinations in Phase II. Simulation studies demonstrated the utility of the proposed zone-finding stage and proved that the operating characteristic of the proposed method was no worse than the existing method. The sensitivity of the proposed method, as well as the operating characteristic of this method when the efficacy outcome is delayed, was also examined.
Six months of adjuvant chemotherapy is regarded as the standard of care for patients with stage III colon cancer. However, whether longer treatment can improve prognosis has not been fully investigated. We conducted a phase III study comparing 6 and 12 months of adjuvant capecitabine chemotherapy for stage III colon cancer, and report here the results of our preplanned safety analysis.
Following the first phase III study of edaravone for amyotrophic lateral sclerosis (ALS), this extension study was performed to evaluate longer -term efficacy and safety. Patients given edaravone in the first 24 -week phase III study (Cycles 1-6) were randomised to edaravone (E -E) or placebo (E -P) in the subsequent 24 -week double-blind period (Cycles 7-12). Patients given placebo in phase III were switched to edaravone (P -E). Subsequently, all patients received edaravone for 12 weeks (Cycles 13-15). Efficacy endpoints included revised ALS Functional Rating Scale (ALSFRS-R) score. Analysis populations were the full analysis set (FAS) and the efficacy -expected subpopulation (EESP) defined by post -hoc analysis of the first phase III study. The least -squares mean and standard error of the intergroup difference (E -E vs. E -P) of change in the ALSFRS-R score from Cycles 7-12 was 1.16 perpendicular to 1 0.93 (p= 0.2176) in the FAS, and 1.85 1.14 (p = 0.1127) in the EESP. The ALSFRS-R score changed almost linearly in the E -E group throughout Cycles 1-15 (60 weeks). The incidence of serious adverse events associated with ALS progression was higher in E -E than in E -P. Edaravone might have potential efficacy for up to 15 cycles when used to treat patients in the EESP with careful safety monitoring.
The aim of the present study was to determine whether or not the overall survival ( OS ) and disease‐free survival ( DFS ) were affected by the tumor location in patients who underwent curative resection for colon cancer in a pooled analysis of three large phase III studies performed in Japan. In total, 4029 patients were included in the present study. Patients were classified as having right‐side colon cancer ( RC ) if the primary tumor was located in the cecum, ascending colon, hepatic flexure or transverse colon, and left‐side colon cancer ( LCC ) if the tumor site was within the splenic flexure, descending colon, sigmoid colon or recto sigmoid junction. The risk factors for the OS and DFS were analyzed. In the present study, 1449 patients were RC , and 2580 were LCC . The OS rates at 3 and 5 years after surgery were 87.6% and 81.6% in the RC group and 91.5% and 84.5% in the LCC group, respectively. Uni‐ and multivariate analyses showed that RRC increased the risk of death by 19.7% (adjusted hazard ratio = 1.197; 95% confidence interval, 1.020–1.408; P = 0.0272). In contrast, the DFS was similar between the two locations. The present study confirmed that the tumor location was a risk factor for the OS in patients who underwent curative treatment for colon cancer. Tumor location may, therefore, need to be considered a stratification factor in future phase III trials of colon cancer.
BACKGROUND:Three randomised trials (GEST, JACCRO PC-01, and GEMSAP) were conducted to evaluate the efficacy of gemcitabine plus S-1 (GS) vs gemcitabine alone in patients with advanced pancreatic cancer (PC). In this pooled analysis, the efficacy and safety of GS vs gemcitabine were evaluated.METHODS:Additional follow-up was conducted and survival data were updated in each study. A total of 770 patients (gemcitabine 389; GS 381) were included in the pooled analysis. The efficacy and safety data were analysed according to disease extent: locally advanced PC (LAPC) or metastatic PC (MPC).RESULTS:There were 738 (95.8%) overall survival events. In patients with LAPC (n=193), the median survival was 11.83 months for gemcitabine and 16.41 months for GS (hazard ratio (HR)=0.708; 95% confidence intervals (CI), 0.527-0.951; P=0.0220). In patients with MPC (n=577), the median survival was 8.02 months for gemcitabine and 9.43 months for GS (HR=0.872; 95% CI, 0.738-1.032; P=0.1102). The rate of grade 3/4 toxicity (rash and thrombocytopenia in LAPC; rash, diarrhoea, vomiting, and neutropaenia in MPC) was significantly higher for GS than for gemcitabine.CONCLUSIONS:Gemcitabine plus S-1 is a viable treatment alternative to gemcitabine, which is one of the standard treatments in patients with LAPC.
Purpose: Reliable risk estimates of recurrence are necessary to establish optimal postoperative surveillance strategies. The purpose of the present study was to clarify changes in the hazard rate (HR) for tumor recurrence over time in Japanese patients with colon cancer. Methods: Data for 3984 patients from three clinical trials evaluating the benefit of adjuvant chemotherapy for colon cancer were analyzed. Estimated HRs were plotted over time for the entire cohort, as well as for node-positive and node-negative patients separately. The changes in risk were further analyzed according to eight clinical variables, and factors predictive of early (<3 years) and late (>3 years) recurrence were explored using Cox's regression analysis. Results: In node-positive patients, there was a prominent HR peak 0.6 years after surgery, whereas HR remained at consistently low levels in node-negative patients. In node-positive patients, HR decreased steadily until 3 years, after which the decline in HR plateaued. Those with T4 tumors had a prominent HR peak around 1 year, including node-negative patients. The HR for T1/T2 Stage III colon cancers showed a similar pattern as that for T1-T3 node-negative colon cancers. Cox regression analysis revealed that a lack of adjuvant chemotherapy, positive node status, T3/T4 factors, and male gender predict early recurrence, whereas patients with lymph node metastasis, T4 tumors, and a lesser extent of lymph node removal have a higher risk of recurrence 3-4 years after surgery (P<0.05). Conclusion: The present study supports the concept of intensive surveillance during the first 3 years after curative resection. However, a reduction in surveillance intensity may be acceptable for patients with T3 Stage II and T1/T2 Stage III colon cancer.