scholarly journals Bayesian Adaptive Randomized Trial Design for Patients With Recurrent Glioblastoma

2012 ◽  
Vol 30 (26) ◽  
pp. 3258-3263 ◽  
Author(s):  
Lorenzo Trippa ◽  
Eudocia Q. Lee ◽  
Patrick Y. Wen ◽  
Tracy T. Batchelor ◽  
Timothy Cloughesy ◽  
...  

Purpose To evaluate whether the use of Bayesian adaptive randomized (AR) designs in clinical trials for glioblastoma is feasible and would allow for more efficient trials. Patients and Methods We generated an adaptive randomization procedure that was retrospectively applied to primary patient data from four separate phase II clinical trials in patients with recurrent glioblastoma. We then compared AR designs with more conventional trial designs by using realistic hypothetical scenarios consistent with survival data reported in the literature. Our primary end point was the number of patients needed to achieve a desired statistical power. Results If our phase II trials had been a single, multiarm trial using AR design, 30 fewer patients would have been needed compared with a multiarm balanced randomized (BR) design to attain the same power level. More generally, Bayesian AR trial design for patients with glioblastoma would result in trials with fewer overall patients with no loss in statistical power and in more patients being randomly assigned to effective treatment arms. For a 140-patient trial with a control arm, two ineffective arms, and one effective arm with a hazard ratio of 0.6, a median of 47 patients would be randomly assigned to the effective arm compared with 35 in a BR trial design. Conclusion Given the desire for control arms in phase II trials, an increasing number of experimental therapeutics, and a relatively short time for events, Bayesian AR designs are attractive for clinical trials in glioblastoma.

2012 ◽  
Vol 30 (15_suppl) ◽  
pp. 2005-2005
Author(s):  
Brian Michael Alexander ◽  
Patrick Y. Wen ◽  
Eudocia Quant Lee ◽  
Tracy Batchelor ◽  
Timothy Francis Cloughesy ◽  
...  

2005 Background: Bayesian-based trial design has the ability to utilize accumulating data in real time to alter the course of the trial, thereby enabling dynamic allocation to experimental arms and earlier dropping of ineffective arms. This flexibility results in a potentially more efficient trial framework by increasing the probability of enrollment to arms that show evidence of efficacy. In this study we considered a hypothetical scenario in which patients who have been previously treated on several separate experimental protocols at the Dana-Farber/Harvard Cancer Center and the University of California, Los Angeles were instead enrolled in a single multi-arm protocol utilizing a Bayesian adaptively randomized trial design. The purpose was to determine whether similar scientific results could have been accomplished more efficiently. Methods: We generated an adaptive randomization procedure that was retrospectively applied to primary patient data from four separate phase II clinical trials in patients with recurrent glioblastoma. We then compared AR to more conventional trial designs using realistic hypothetical scenarios consistent with survival data reported in the literature. Our primary endpoint is the number of patients needed to achieve a desired statistical power. Results: If our phase II trials had been a single multi-arm AR trial, bevacizumab would have been identified as an efficacious therapy, and 30 fewer patients would have been needed compared to a multi-arm balanced randomized (BR) design. More generally, Bayesian AR trial design for patients with glioblastoma would result in trials with fewer overall patients with no loss in statistical power, and in more patients randomized to effective treatment arms. For a trial with a control arm, two ineffective arms and one effective arm with hazard ratio 0.6, a median of 47 patients would be randomized to the effective arm compared with 35 in a BR design. Conclusions: Given the desire for control arms in phase II trials, an increasing number of experimental therapeutics for patients with glioblastoma, and a relatively short time for events, Bayesian adaptive designs are attractive for clinical trials in glioblastoma.


2012 ◽  
Vol 30 (15_suppl) ◽  
pp. 4038-4038
Author(s):  
Katherine Van Loon ◽  
George P. Kim ◽  
Anne Marie Espinoza ◽  
David R. Fogelman ◽  
Renuka V. Iyer ◽  
...  

4038 Background: GEM has served as the chemotherapy platform for most phase III clinical trials in APC, inc. CALGB 80303 (GEM +/- BEV). However, GEM-based combination regimens may confer superior outcomes in select pts and represent a preferred backbone in clinical trial design testing targeted agents. Methods: Data was pooled from 5 phase II trials evaluating GEM-based cytotoxic doublets plus BEV in APC. 1o endpoint was OS. 2o endpoints included ORR, CA19-9 response, and adverse events (AEs). Kaplan-Meier methods estimated time-to-event endpoints. The Cox proportional hazard model estimated univariate hazard ratios (HR) of death. Results: Of 261 pts, 90.7% were Caucasian, 95.4% had an ECOG PS 0-1, and 91.6% had metastatic disease. Median age = 60y. Pooled OS data (in mos), stratified for PS and stage, is shown in the table. ORR across all trials: CR 1.6%, PR 22.9%, SD 50.8%, PD 20.2%, NA 4.7%. HR for pts who achieved disease control (CR/PR/SD) was 0.35 vs. those with PD (95% CI 0.23-0.54, p<0.001). 76.5% of pts had elevated baseline CA19-9; of these, 62% achieved ≥50% reduction (HR 0.50; 95% CI 0.34-0.73, p<0.001). BEV-related AEs ≥grade 3: HTN (10.6%), hemorrhage (9.5%), VTE (10.1%), cardiac events (3.4%), and bowel perforation (2.2%). Median OS in pts with grade 3-4 HTN was 13.4 mos vs. 9.8 mos in those without (HR 0.77; 95% CI 0.48-1.24, p=0.29). Conclusions: Recognizing the limitations of single-arm phase II trial design and cross-study comparisons, these results compare favorably to those from CALGB 80303. The standard paradigm of GEM +/- drug X in clinical trial development for APC needs to be reconsidered. Based on our data as well as the recent phase III FOLFIRINOX study, building on more intensive combination chemo regimens in future trials may represent a better strategy, especially for pts with good PS. [Table: see text]


2006 ◽  
Vol 24 (1) ◽  
pp. 136-140 ◽  
Author(s):  
Andrew J. Vickers ◽  
Joyce Kuo ◽  
Barrie R. Cassileth

Purpose A substantial number of cancer patients turn to treatments other than those recommended by mainstream oncologists in an effort to sustain tumor remission or halt the spread of cancer. These unconventional approaches include botanicals, high-dose nutritional supplementation, off-label pharmaceuticals, and animal products. The objective of this study was to review systematically the methodologies applied in clinical trials of unconventional treatments specifically for cancer. Methods MEDLINE 1966 to 2005 was searched using approximately 200 different medical subject heading terms (eg, alternative medicine) and free text words (eg, laetrile). We sought prospective clinical trials of unconventional treatments in cancer patients, excluding studies with only symptom control or nonclinical (eg, immune) end points. Trial data were extracted by two reviewers using a standardized protocol. Results We identified 14,735 articles, of which 214, describing 198 different clinical trials, were included. Twenty trials were phase I, three were phase I and II, 70 were phase II, and 105 were phase III. Approximately half of the trials investigated fungal products, 20% investigated other botanicals, 10% investigated vitamins and supplements, and 10% investigated off-label pharmaceuticals. Only eight of the phase I trials were dose-finding trials, and a mere 20% of phase II trials reported a statistical design. Of the 27 different agents tested in phase III, only one agent had a prior dose-finding trial, and only for three agents was the definitive study initiated after the publication of phase II data. Conclusion Unconventional cancer treatments have not been subject to appropriate early-phase trial development. Future research on unconventional therapies should involve dose-finding and phase II studies to determine the suitability of definitive trials.


2006 ◽  
Vol 24 (18_suppl) ◽  
pp. 7108-7108 ◽  
Author(s):  
R. K. Bagai ◽  
A. Dowlati

7108 Background: A significant heterogeneity exists in the design and reporting of phase II and III therapeutic clinical trials in NSCLC. This has led to difficulty in interpretation of these trials leading to over- or underestimation of therapeutic efficacy. We set out to investigate the statistical methodology and design reporting of chemotherapeutic trials in NSCLC published in the Journal of Clinical Oncology (JCO) over 20 years. Methods: We identified all phase II and III NSCLC chemotherapy trials published in the JCO from January 1983 to August 2005. All manuscripts were reviewed to evaluate components of statistical design that were reported, including: sample size calculation, power, type I error, single or multiple drug trials, relative response sought in phase II trials and improvement in survival time or response rate sought in phase III trials. Results: One hundred forty eight trials were identified. 52% of studies were phase III and 48% were phase II. The majority (78%) were conducted in advanced stage NSCLC. Sample size calculations were reported for only 58% of phase III studies and 31% of phase II studies. Power was reported in 66% of phase III studies and 13% of phase II trials. Type I error was reported in 47% of phase III studies and 17% in phase II studies. 60% of phase III trials defined endpoints (percentage improvement in survival time, improvement in survival time in months or increase in response rate). 41% of phase II trails defined the target response rate, ranging from response rates of 15% to 70%. The frequency of adequate reporting of statistical design was shown to increase from 31% in 1990–1995 to 64% in 2000–2005 ( table ). Conclusions: Significant heterogeneity exists in trial design and reporting of phase II and III trials in NSCLC. This impacts the ability to adequately interpret these studies. More widespread application of statistical methods in planning and reporting of lung cancer clinical trials are necessary to increase reliability of data. [Table: see text] No significant financial relationships to disclose.


2013 ◽  
Vol 31 (15_suppl) ◽  
pp. 4036-4036 ◽  
Author(s):  
Daniel M. Halperin ◽  
J. Jack Lee ◽  
James C. Yao

4036 Background: Few new therapies for pancreatic adenocarcinoma (PC) have been approved by the Food and Drug Administration (FDA) or recommended by the National Comprehensive Cancer Network (NCCN), reflecting frequent failures in phase III trials. We hypothesize that the high failure rate in large trials is due to a low predictive value for “positive” phase II studies. Methods: Given a median time from initiation of clinical trials to FDA approval of 6.3 years, we conducted a systematic search of the clinicaltrials.gov database for phase II interventional trials of antineoplastic therapy in PC initiated from 1999-2004. We reviewed drug labels and NCCN guidelines for FDA approval and guideline recommendations. Results: We identified 70 phase II trials that met our inclusion criteria. Forty-five evaluated compounds without preexisting FDA approval, 23 evaluated drugs approved in other diseases, and 2 evaluated cellular therapies. With a median follow-up of 12.5 years, none of these drugs gained FDA approval in PC. Four trials, all combining chemotherapy with radiation, eventually resulted in NCCN recommendations. Forty-two of the trials have been published. Of 16 studies providing pre-specified type I error rates, these rates were ≥0.1 in 8 studies, 0.05 in 6 studies and <0.025 in 2 studies. Of 21 studies specifying type II error rates, 7 used >0.1, 10 used 0.1, and 4 used <0.1. Published studies reported a median enrollment of 47 subjects. Fourteen trials reported utilizing a randomized design. Conclusions: The low rate of phase II trials resulting in eventual regulatory approval of therapies for PC reflects the challenge of conquering a tough disease as well as deficiencies in the statistical designs. New strategies are necessary to quantify and improve odds of success in drug development. Statistical parameters of individual or coupled phase II trials should be tailored to achieve the desired predictive value prior to initiating pivotal phase III studies. Positive predictive value of a phase II study assuming a 1%, 2%, or 5% prior probability of success and 10% type II error rate. [Table: see text]


2013 ◽  
Vol 31 (15_suppl) ◽  
pp. TPS6099-TPS6099
Author(s):  
David Ira Rosenthal ◽  
Qiang Zhang ◽  
Merrill S. Kies ◽  
Minh-Tam Truong ◽  
Richard Jordan ◽  
...  

TPS6099 Background: Clinical trial results from phase II trials to select an experimental treatment arm for separate phase III trial comparison can require years. Cancer clinical trials also now aim at both survival and PRO/functional outcomes, especially in head and neck (HN) studies. We developed a unique seamless phase II/III trial design to save on sample size and trial duration. The initial multi-arm phase II trial selects the most effective regimen among multiple experimental arms by first comparing each of the new treatments to a common control arm, using chosen endpoints, such as progression free survival. The winner will be tested for overall survival in the phase III study. Methods: We propose a phase II/III design to test the efficacy of experimental arms of postoperative radiation (RT) + docetaxel or RT + docetaxel + cetuximab in patients with HN squamous cancer. These are compared to the control arm of RT + cisplatin in the phase II part. Only one arm will be selected to go on to phase III depending on efficacy (PFS), PRO and safety outcomes. One experimental arm must be sufficiently better than the common control arm and the winner not having increased toxicity or functional cost to be selected for phase III inclusion. If not, the trial is halted for futility. Patients in the phase II selected arm and the control arm are included in phase III testing. Group sequential method is used to design each component. Separate interim efficacy and futility analyses are built in such that each endpoint can be monitored as in separate phase II, III trials. Once sample sizes are derived, operating characteristics for the seamless II/III design are evaluated through simulations under the null and various alternative hypotheses. Savings on sample size and time are compared to typical separate phase II and III designs and to the design testing only the arm of RT + docetaxel + cetuximab in phase II. Conclusion: The phase II/III RTOG 1216 HNC trial offers cost effectiveness, operational efficiency and scientific innovation.


2016 ◽  
Vol 27 (1) ◽  
pp. 158-171 ◽  
Author(s):  
Haolun Shi ◽  
Guosheng Yin

Conventional phase II clinical trials use either a single- or multi-arm comparison scheme to examine the therapeutic effects of the experimental drug. Both single- and multi-arm evaluations have their own merits; for example, single-arm phase II trials are easy to conduct and often require a smaller sample size, while multiarm trials are randomized and typically lead to a more objective comparison. To bridge the single- and double-arm schemes in one trial, we propose a two-stage design, in which the first stage takes a single-arm comparison of the experimental drug with the standard response rate (no concurrent treatment) and the second stage imposes a two-arm comparison by adding an active control arm. The design is calibrated using a new concept, the detectable treatment difference, to balance the trade-offs between futility termination, power, and sample size. We conduct extensive simulation studies to examine the operating characteristics of the proposed method and provide an illustrative example of our design.


2021 ◽  
Author(s):  
Jincai Guo ◽  
Hui Xie ◽  
Hao Wu

Abstract Background: The purpose of this study is to analyze the registered clinical trials of COVID-19, and to provide a reference for the clinical treatment of COVID-19. Methods: Chinese ClinicalTrial Registry (ChiCTR) and Clinicaltrials.gov databases were searched for clinical trials of COVID-19, which were registered from inception to February 29, 2020, to screen out the clinical trials on the treatment of COVID-19, and the research units and regions, sample size, study types, study stages, and intervention measures were analyzed. Results: There were 226 clinical trials on COVID-19 in the 2 databases, and all of them were registered by research units in China. The top five registered areas were Hubei, Beijing, Shanghai, Guangdong, and Zhejiang. The study type was as follows: interventional study (207, 91.6%) and observational study (18, 8.0%). Clinical trial staging was as follows: exploratory studies/preliminary trials (91, 40.3%), phase I trials (4, 1.8%), phase II trials (12, 5.3%), phase III trials (12, 5.3%), phase IV trials (47, 20.8%), phase I/II trials (2, 0.9%), phase II/III trials (5, 2.2%), and other trials (57, 25.2%). Intervention measures were as follows: there were 143 (63.3%) trials of western medicine treatment, 50 (22.1%) trials of Chinese medicine treatment, and 21 (9.3%) trials of integrated Chinese medicine treatment and western medicine treatment. Conclusion: Researchers have registered a large number of clinical trials in a short time. The number of existing patients of COVID-19 is not enough to support hundreds of clinical trials. There is a lack of multicenter, randomized, double-blind, placebo-controlled trials.


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