A phase II trial design with direct assignment option for initial marker validation.

2012 ◽  
Vol 30 (30_suppl) ◽  
pp. 34-34 ◽  
Author(s):  
Sumithra J. Mandrekar ◽  
Ming-Wen An ◽  
Daniel J. Sargent

34 Background: Phase II clinical trials aim to identify promising experimental regimens for further testing in phase III trials. Testing targeted therapies with predictive biomarkers mandates efficient trial designs. Current biomarker-based trial designs, including the enrichment, all-comers, and adaptive designs, randomize patients to receive treatment or not throughout the entire duration of the trial. Recognizing the need for randomization yet acknowledging the possibility of promising but nonconclusive results after a preplanned interim analysis (IA), we propose a two-stage phase II design that allows for the possibility of direct assignment (i.e., stop randomization and assign all patients to the experimental arm in stage II) based on IA results. Methods: Using simulations, we compared properties of the direct assignment option design to a 1:1 randomized phase II design and assessed the impact of the timing of IA (after 33%, 50%, or 67% of accrual) and number of IA (one versus two with option for direct assignment at the first and second) over a range of response rate ratios (between 1.0 and 3.0). Results: Between 12% and 30% of the trials (out of 6,000 simulated trials) adopt direct assignment in stage II, with direct adoption depending on the treatment effect size and specified type I error rate (TIER). The direct assignment option design has minimal loss in power (<1.8%) and minimal increase in T1ER (<2.1%) compared to a 1:1 randomized design. The maximum loss in power across possible timings of IA was <1.2%. For the direct assignment option design, there was a 20%-50% increase in the number of patients treated on the experimental (vs. control) arm for the 1 IA case, and 40%-100% increase for the 2 IA case. Conclusions: Testing predictive biomarkers in clinical trials requires new design strategies. In the spectrum of phase II designs from adaptive to balanced randomized all-comers or enrichment designs, the direct assignment design provides a middle ground with desirable statistical properties that may appeal to both clinicians and patients.

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]


2015 ◽  
Vol 33 (26) ◽  
pp. 2914-2919 ◽  
Author(s):  
Daniel M. Halperin ◽  
J. Jack Lee ◽  
Cecile Gonzales Dagohoy ◽  
James C. Yao

Purpose Despite a robust clinical trial enterprise and encouraging phase II results, the vast minority of oncologic drugs in development receive regulatory approval. In addition, clinicians occasionally make therapeutic decisions based on phase II data. Therefore, clinicians, investigators, and regulatory agencies require improved understanding of the implications of positive phase II studies. We hypothesized that prior probability of eventual drug approval was significantly different across GI cancers, with substantial ramifications for the predictive value of phase II studies. Methods We conducted a systematic search of phase II studies conducted between 1999 and 2004 and compared studies against US Food and Drug Administration and National Cancer Institute databases of approved indications for drugs tested in those studies. Results In all, 317 phase II trials were identified and followed for a median of 12.5 years. Following completion of phase III studies, eventual new drug application approval rates varied from 0% (zero of 45) in pancreatic adenocarcinoma to 34.8% (24 of 69) for colon adenocarcinoma. The proportion of drugs eventually approved was correlated with the disease under study (P < .001). The median type I error for all published trials was 0.05, and the median type II error was 0.1, with minimal variation. By using the observed median type I error for each disease, phase II studies have positive predictive values ranging from less than 1% to 90%, depending on primary site of the cancer. Conclusion Phase II trials in different GI malignancies have distinct prior probabilities of drug approval, yielding quantitatively and qualitatively different predictive values with similar statistical designs. Incorporation of prior probability into trial design may allow for more effective design and interpretation of phase II studies.


2016 ◽  
Vol 14 (1) ◽  
pp. 48-58 ◽  
Author(s):  
Qiang Zhang ◽  
Boris Freidlin ◽  
Edward L Korn ◽  
Susan Halabi ◽  
Sumithra Mandrekar ◽  
...  

Background: Futility (inefficacy) interim monitoring is an important component in the conduct of phase III clinical trials, especially in life-threatening diseases. Desirable futility monitoring guidelines allow timely stopping if the new therapy is harmful or if it is unlikely to demonstrate to be sufficiently effective if the trial were to continue to its final analysis. There are a number of analytical approaches that are used to construct futility monitoring boundaries. The most common approaches are based on conditional power, sequential testing of the alternative hypothesis, or sequential confidence intervals. The resulting futility boundaries vary considerably with respect to the level of evidence required for recommending stopping the study. Purpose: We evaluate the performance of commonly used methods using event histories from completed phase III clinical trials of the Radiation Therapy Oncology Group, Cancer and Leukemia Group B, and North Central Cancer Treatment Group. Methods: We considered published superiority phase III trials with survival endpoints initiated after 1990. There are 52 studies available for this analysis from different disease sites. Total sample size and maximum number of events (statistical information) for each study were calculated using protocol-specified effect size, type I and type II error rates. In addition to the common futility approaches, we considered a recently proposed linear inefficacy boundary approach with an early harm look followed by several lack-of-efficacy analyses. For each futility approach, interim test statistics were generated for three schedules with different analysis frequency, and early stopping was recommended if the interim result crossed a futility stopping boundary. For trials not demonstrating superiority, the impact of each rule is summarized as savings on sample size, study duration, and information time scales. Results: For negative studies, our results show that the futility approaches based on testing the alternative hypothesis and repeated confidence interval rules yielded less savings (compared to the other two rules). These boundaries are too conservative, especially during the first half of the study (<50% of information). The conditional power rules are too aggressive during the second half of the study (>50% of information) and may stop a trial even when there is a clinically meaningful treatment effect. The linear inefficacy boundary with three or more interim analyses provided the best results. For positive studies, we demonstrated that none of the futility rules would have stopped the trials. Conclusion: The linear inefficacy boundary futility approach is attractive from statistical, clinical, and logistical standpoints in clinical trials evaluating new anti-cancer agents.


2019 ◽  
Author(s):  
Emma Wang ◽  
Bernard North ◽  
Peter Sasieni

Abstract Abstract Background Rare and uncommon diseases are difficult to study in clinical trials due to limited recruitment. If the incidence of the disease is very low, international collaboration can only solve the problem to a certain extent. A consequence is a disproportionately high number of deaths from rare diseases, due to unclear knowledge of the best way to treat patients suffering from these diseases. Hypothesis testing using the conventional Type I error in conjunction with the number of patients who can realistically be enrolled for a rare disease, would cause the trial to be severely underpowered. Methods Our proposed method recognises these pragmatic limitations and suggests a new testing procedure, wherein conclusion of efficacy of one arm is grounded in robust evidence of non-inferiority in the endpoint of interest, and reasonable evidence of superiority, over the other arm. Results Simulations were conducted to illustrate the gains in statistical power compared with conventional hypothesis testing in several statistical settings as well as the example of clinical trials for Merkel cell carcinoma, a rare skin tumour. Conclusions Our proposed analysis method enables conducting clinical trials for rare diseases, potentially leading to better standard of care for patients suffering from rare diseases


2012 ◽  
Vol 30 (15_suppl) ◽  
pp. e18112-e18112
Author(s):  
Neeta Somaiah ◽  
George R. Simon

e18112 Background: A plethora of targeted agents are currently being evaluated in patients with NSCLC. The number of targeted agents exceeds the number of targets leading to many targeted agents being evaluated against similar targets. The identification of new targets are likely to increase exponentially in the near future given the numerous currently ongoing molecular profiling efforts. The objective of this analysis is to estimate the target-specific patient resource utilization and its impact on routine clinical care. Methods: A comprehensive search for molecularly targeted agents in clinical testing that have accrued or are accruing NSCLC patients were performed by using publically available search engines and databases. Agents were grouped according to the primary target and the phase of development. We computed the number of patients allocated to completed and ongoing phase III NSCLC trials for advanced NSCLC alone. Results: There are more than 30 categories of molecular targets accruing NSCLC patients in clinical trials. By conservative estimates, approximately 215 agents are currently undergoing clinical testing. The median number of agents per target is 7 (range 2 (HIF-1α and PDGFRα) – 24 (EGFR)). There are 7 EGFR inhibitors and 10 VEGFR inhibitors that were evaluated in phase III trials; with 36,093 and 20,313 stage IV NSCLC patients enrolled or to be enrolled in these trials, respectively. No more than 2 agents per target have been FDA approved for NSCLC to date. Further details of the analyses will be more comprehensively presented at the meeting. Conclusions: Patient resource utilization is unevenly distributed across targets. The optimal number of targeted agents to be evaluated per target remains to be defined. More emphasis on identifying new targets and targeting these with limited number of optimal agents may accelerate the advancement of the field and the impact on patient care.


2021 ◽  
Vol 39 (3_suppl) ◽  
pp. TPS148-TPS148
Author(s):  
Van K. Morris ◽  
Greg Yothers ◽  
Scott Kopetz ◽  
Samuel A. Jacobs ◽  
Peter C. Lucas ◽  
...  

TPS148 Background: There are currently no validated predictive biomarkers for stage II resected colon cancer (CC) after adjuvant chemotherapy. However, circulating tumor DNA (ctDNA) that is shed into the bloodstream represents a highly specific and sensitive approach for identifying microscopic or residual tumor cells. For patients (pts) with CC, the detection of ctDNA is associated with persistent disease after resection and may outperform traditional clinical and pathological features as a prognostic factor to assess risk for recurrence. We hypothesize that for pts whose stage II colon cancer has been resected and who have no traditional high-risk features, a positive ctDNA status may identify those who will benefit from adjuvant chemotherapy. Methods: In this prospective phase II/III clinical trial, pts (N=1,408) with resected stage II CC without traditional high-risk features and whom the evaluating oncologist deems suitable for no adjuvant chemotherapy will be randomized 1:1 into 2 arms:standard-of-care/observation (Arm A), or prospective testing for ctDNA (Arm B). Postoperative blood will be analyzed for ctDNA with the GuardantHealth LUNAR panel, covering CC-relevant mutations and CC-specific methylation profiling. Pts in Arm B with ctDNA detected will be treated with 6 months of adjuvant (FOLFOX) chemotherapy. For all pts in Arm A, ctDNA status will be analyzed retrospectively at the time of endpoint analysis. The primary endpoints are clearance of ctDNA with adjuvant chemotherapy (phase II) and recurrence-free survival (RFS) for “ctDNA-detected” pts treated with or without adjuvant chemotherapy (phase III). Secondary endpoints will include time-to-event outcomes (OS, RFS, TTR) by ctDNA marker status and treatment, prevalence of detectable ctDNA in stage II CC, and rates of compliance with assigned intervention. Archived normal and matched tumor and blood samples will be collected for exploratory correlative research. The trial is actively accruing towards the phase II endpoint across all US and Canadian cooperative groups. Support:U10-CA-180868, -180822; UG1CA-189867; GuardantHealth. Clinical trial information: NCT04068103.


2009 ◽  
Vol 27 (33) ◽  
pp. 5660-5669 ◽  
Author(s):  
Philip A. Philip ◽  
Margaret Mooney ◽  
Deborah Jaffe ◽  
Gail Eckhardt ◽  
Malcolm Moore ◽  
...  

Pancreatic ductal adenocarcinoma (PDAC) is the fourth leading cause of cancer mortality, despite significant improvements in diagnostic imaging and operative mortality rates. The 5-year survival rate remains less than 5% because of microscopic or gross metastatic disease at time of diagnosis. The Clinical Trials Planning Meeting in pancreatic cancer was convened by the National Cancer Institute's Gastrointestinal Cancer Steering Committee to discuss the integration of basic and clinical knowledge in the design of clinical trials in PDAC. Major emphasis was placed on the enhancement of research to identify and validate the relevant targets and molecular pathways in PDAC, cancer stem cells, and the microenvironment. Emphasis was also placed on developing rational combinations of targeted agents and the development of predictive biomarkers to assist selection of patient subsets. The development of preclinical tumor models that are better predictive of human PDAC must be supported with wider availability to the research community. Phase III clinical trials should be implemented only if there is a meaningful clinical signal of efficacy and safety in the phase II setting. The emphasis must therefore be on performing well-designed phase II studies with uniform sets of basic entry and evaluation criteria with survival as a primary endpoint. Patients with either metastatic or locally advanced PDAC must be studied separately.


2007 ◽  
Vol 25 (32) ◽  
pp. 5058-5062 ◽  
Author(s):  
Lynne I. Wagner ◽  
Lari Wenzel ◽  
Edward Shaw ◽  
David Cella

With increasing limits on the resources available to conduct cancer clinical trials, the inclusion of patient-reported outcomes (PROs) in treatment and symptom management trials must be prioritized. Although it has been suggested on occasion that phase III trials should take precedence over phase II trials, we argue that there is a clear and important role for PRO assessment in phase II trials going forward. To illustrate the value realized from including PROs in phase II trials, we provide case examples from cancer treatment and supportive care. The benefits of including PROs in symptom management intervention research are exemplified using phase II trials targeting cognitive impairment. The inclusion of PROs in phase II cancer clinical trials adds important information about the impact of treatment in health-related quality of life, and advances the science of PRO measurement. These contributions significantly enhance the design of phase III trials, ultimately leading to the efficient utilization of clinical trial resources.


2019 ◽  
Vol 37 (15_suppl) ◽  
pp. TPS1117-TPS1117 ◽  
Author(s):  
Steven J. Chmura ◽  
Kathryn A. Winter ◽  
Hania A Al-Hallaq ◽  
Virginia F. Borges ◽  
Nora T. Jaskowiak ◽  
...  

TPS1117 Background: This is a randomized Phase II/III trial to evaluate if stereotactic body radiotherapy (SBRT) and/or surgical resection (SR) of all metastatic sites in newly oligo-metastatic breast cancer who have received up to 12 months of first line systemic therapy without progression will significantly improve median progression free survival (PFS). If this aim is met the trial continues as a phase III to evaluate if SBRT/SR improves 5 year overall survival. Secondary aims include local control in the metastatic site, new distant metastatic rate, and technical quality. Translational primary endpoint is to determine whether < 5 CTCs is an independent prognostic marker for improved PFS and OS. Methods: Women with pathologically confirmed metastatic breast cancer to ≤ 4 sites who have been diagnosed within 365 days with metastatic disease and the primary tumor site disease is controlled. CNS metastases are ineligible. ER/PR and HER-2 neu status is required. Site radiation credentialing with a facility questionnaire and pre-treatment review of first case is required. Randomization is to standard systemic therapy with local radiotherapy/ surgery for palliation when necessary versus ablative therapy of all metastases with SBRT and/or SR. For the phase IIR portion to detect a signal for improved median PFS from 10.5 months to 19 months with 95% power and a 1-sided alpha of 0.15 and accounting for ineligible/lost patients, 128 patients will be required. For the Phase III, an additional 232 patients will be required to definitively determine if ablative therapy improves 5-year overall survival from 28% to 42.5% (HR=0.67), with 85% power and a one-sided type I error of 0.025. For the translational research assuming a two-sided probability of type I error of 0.05, the number of patients accrued in the Phase II-R and Phase III portions will provide sufficient power of at least 91% and 93% to detect whether < 5 CTC’s is prognostic for PFS and OS, respectively. Present accrual (1-31-2019): 105. Contact Information: Protocol: CTSU member web site https://www.ctsu.org . Enrollment: OPEN at https://open.ctsu.org . Support: This project is supported by NRG Oncology grants U10CA180868 and U10CA180822 from the National Cancer Institute (NCI). Translational science is supported by the Ludwig Foundation for Cancer Research. Clinical trial information: NCT02364557.


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