A Bayesian Hybrid Adaptive Randomisation Design for Clinical Trials with Survival Outcomes

2016 ◽  
Vol 55 (01) ◽  
pp. 4-13
Author(s):  
M. Moatti ◽  
S. Zohar ◽  
W. F. Rosenberger ◽  
S. Chevret

SummaryBackground: Response-adaptive randomisation designs have been proposed to im -prove the efficiency of phase III randomised clinical trials and improve the outcomes of the clinical trial population. In the setting of failure time outcomes, Zhang and Rosen -berger (2007) developed a response-adaptive randomisation approach that targets an optimal allocation, based on a fixed sample size. Objectives: The aim of this research is to propose a response-adaptive randomisation procedure for survival trials with an interim monitoring plan, based on the following optimal criterion: for fixed variance of the esti -mated log hazard ratio, what allocation minimizes the expected hazard of failure? We demonstrate the utility of the design by re -designing a clinical trial on multiple myeloma. Methods: To handle continuous monitoring of data, we propose a Bayesian response-adap -tive randomisation procedure, where the log hazard ratio is the effect measure of interest. Combining the prior with the normal likelihood, the mean posterior estimate of the log hazard ratio allows derivation of the optimal target allocation. We perform a simu lationstudy to assess and compare the perform -ance of this proposed Bayesian hybrid adaptive design to those of fixed, sequential or adaptive – either frequentist or fully Bayesian – designs. Non informative normal priors of the log hazard ratio were used, as well as mixture of enthusiastic and skeptical priors. Stopping rules based on the posterior dis -tribution of the log hazard ratio were com -puted. The method is then illus trated by redesigning a phase III randomised clinical trial of chemotherapy in patients with multiple myeloma, with mixture of normal priors elicited from experts. Results: As expected, there was a reduction in the proportion of observed deaths in the adaptive vs. non-adaptive designs; this reduction was maximized using a Bayes mix -ture prior, with no clear-cut improvement by using a fully Bayesian procedure. The use of stopping rules allows a slight decrease in the observed proportion of deaths under the alternate hypothesis compared with the adaptive designs with no stopping rules. Conclusions: Such Bayesian hybrid adaptive survival trials may be promising alternatives to traditional designs, reducing the duration of survival trials, as well as optimizing the ethical concerns for patients enrolled in the trial.

2016 ◽  
Vol 27 (3) ◽  
pp. 891-904 ◽  
Author(s):  
Fumiyasu Komaki ◽  
Atanu Biswas

Response-adaptive designs are used in phase III clinical trials to allocate a larger number of patients to the better treatment arm. Optimal designs are explored in the recent years in the context of response-adaptive designs, in the frequentist view point only. In the present paper, we propose some response-adaptive designs for two treatments based on Bayesian prediction for phase III clinical trials. Some properties are studied and numerically compared with some existing competitors. A real data set is used to illustrate the applicability of the proposed methodology where we redesign the experiment using parameters derived from the data set.


BMC Medicine ◽  
2020 ◽  
Vol 18 (1) ◽  
Author(s):  
Thomas Burnett ◽  
Pavel Mozgunov ◽  
Philip Pallmann ◽  
Sofia S. Villar ◽  
Graham M. Wheeler ◽  
...  

AbstractAdaptive designs for clinical trials permit alterations to a study in response to accumulating data in order to make trials more flexible, ethical, and efficient. These benefits are achieved while preserving the integrity and validity of the trial, through the pre-specification and proper adjustment for the possible alterations during the course of the trial. Despite much research in the statistical literature highlighting the potential advantages of adaptive designs over traditional fixed designs, the uptake of such methods in clinical research has been slow. One major reason for this is that different adaptations to trial designs, as well as their advantages and limitations, remain unfamiliar to large parts of the clinical community. The aim of this paper is to clarify where adaptive designs can be used to address specific questions of scientific interest; we introduce the main features of adaptive designs and commonly used terminology, highlighting their utility and pitfalls, and illustrate their use through case studies of adaptive trials ranging from early-phase dose escalation to confirmatory phase III studies.


2018 ◽  
Vol 38 (5) ◽  
pp. 749-754 ◽  
Author(s):  
Olivia Kiwanuka ◽  
Bo-Michael Bellander ◽  
Anders Hånell

When evaluating the design of pre-clinical studies in the field of traumatic brain injury, we found substantial differences compared to phase III clinical trials, which in part may explain the difficulties in translating promising experimental drugs into approved treatments. By using network analysis, we also found cases where a large proportion of the studies evaluating a pre-clinical treatment was performed by inter-related researchers, which is potentially problematic. Subjecting all pre-clinical trials to the rigor of a phase III clinical trial is, however, likely not practically achievable. Instead, we repeat the call for a distinction to be made between exploratory and confirmatory pre-clinical studies.


2007 ◽  
Vol 89 (3) ◽  
pp. 207-211 ◽  
Author(s):  
JF Thorpe ◽  
S Jain ◽  
TH Marczylo ◽  
AJ Gescher ◽  
WP Steward ◽  
...  

INTRODUCTION Prostate cancer is an excellent target for chemoprevention strategies; given its late age of onset, any delay in carcinogenesis would lead to a reduction in its incidence. This article reviews all the completed and on-going phase III trials in prostate cancer chemoprevention. PATIENTS AND METHODS All phase III trials of prostate cancer chemoprevention were identified within a Medline search using the keywords ‘clinical trial, prostate cancer, chemoprevention’. RESULTS In 2003, the Prostate Cancer Prevention Trial (PCPT) became the first phase III clinical trial of prostate cancer prevention. This landmark study was terminated early due to the 24.8% reduction of prostate cancer prevalence over a 7-year period in those men taking the 5α-reductase inhibitor, finasteride. This article reviews the PCPT and the interpretation of the excess high-grade prostate cancer (HGPC) cases in the finasteride group. The lack of relationship between cumulative dose and the HGPC cases, and the possible sampling error of biopsies due to gland volume reduction in the finasteride group refutes the suggestion that this is a genuine increase in HGPC cases. The other on-going phase III clinical trials of prostate cancer chemoprevention – the REDUCE study using dutasteride, and the SELECT study using vitamin E and selenium – are also reviewed. CONCLUSIONS At present, finasteride remains the only intervention shown in long-term prospective phase III clinical trials to reduce the incidence of prostate cancer. Until we have the results of trials using alternative agents including the on-going REDUCE and SELECT trials, the advice given to men interested in prostate cancer prevention must include discussion of the results of the PCPT. The increased rate of HGPC in the finasteride group continues to generate debate; however, finasteride may still be suitable for prostate cancer prevention, particularly in men with lower urinary tract symptoms.


Blood ◽  
2020 ◽  
Vol 136 (Supplement 1) ◽  
pp. 5-6
Author(s):  
Israr Khan ◽  
Abdul Rafae ◽  
Anum Javaid ◽  
Zahoor Ahmed ◽  
Haifza Abeera Qadeer ◽  
...  

Background: Multiple myeloma (MM) is a plasma cell disorder and demonstrates overexpression of B cell maturation antigen (BCMA). Our objective is to evaluate the safety and efficacy of chimeric antigen receptor T cells (CAR-T) against BCMA in patients with relapsed/refractory multiple myeloma (RRMM). Methods: We conducted a systematic literature search using PubMed, Cochrane, Clinicaltrials.gov, and Embase databases. We also searched for data from society meetings. A total of 935 articles were identified, and 610 were screened for relevance. Results: Data from thirty-one original studies with a total of 871 patients (pts) were included based on defined eligibility criteria, see Table 1. Hu et al. reported an overall response rate (ORR) of 100% in 33 pts treated with BCMA CAR-T cells including 21 complete response (CR), 7 very good partial response (VGPR), 4 partial response (PR). Moreover, 32 pts achieved minimal residual disease (MRD) negative status. Chen et al. reported ORR of 88%, 14% CR, 6% VGPR, and 82% MRD negative status with BCMA CAR-T therapy in 17 RRMM pts. In another clinical trial by Han et al. BCMA CAR-T therapy demonstrated an ORR of 100% among 7 evaluable pts with 43% pts having ≥ CR and 14% VGPR. An ORR of 100% with 64% stringent CR (sCR) and 36% VGPR was reported with novel anti-BCMA CART cells (CT103A). Similarly, Li et al. reported ORR of 87.5%, sCR of 50%, VGPR 12.5%, and PR 25% in 16 pts. BCMA targeting agent, JNJ-4528, showed ORR of 91%, including 4sCR, 2CR, 10MRD, and 7VGPR. CAR-T- bb2121 demonstrated ORR of 85%, sCR 36%, CR 9%, VGPR 57%, and MRD negativity of 100% (among 16 responsive pts). GSK2857916, a BCMA targeting CAR-T cells yielded ORR of 60% in both clinical trials. Three studies utilizing bispecific CART cells targeting both BCMA & CD38 (LCARB38M) reported by Zhao et al., Wang et al., and Fan et al. showed ORR of 88%, 88%, & 100% respectively. Topp et al. reported ORR of 31% along with 5 ≥CR and 5 MRD negative status in 42 pts treated with Bi T-cells Engager BiTE® Ab BCMA targeting antigen (AMG420). One clinical trial presented AUTO2 CART cells therapy against BCMA with an ORR of 43%, VGPR of 14%, and PR of 28%. CT053CAR-BCMA showed 14sCR and 5CR with a collective ORR of 87.5% and MRD negative status of 85% in 24 and 20 evaluable pts, respectively. Likewise, Mikkilineni et al. reported an ORR of 83%, sCR of 16.7%, and VGPR & PR of 25% and 41% in 12 pts treated with FHVH-BCMA T cells. Similar results are also reported in other clinical trials of BCMA targeting CART therapy (Table 1). The most common adverse effects exhibited were grade 1-3 hematologic (cytopenia) and cytokine release syndrome (CRS) (mostly reversible with tocilizumab). Conclusion: Initial data from ongoing clinical trials using BCMA targeting CAR-T therapy have yielded promising results both in terms of improved outcome and tolerable toxicity profiles. Although two phase 3 trails are ongoing, additional data is warranted to further ensure the safety and efficacy of anti-BCMA CAR-T cells therapy in pts with RRMM for future use. Disclosures Anwer: Incyte, Seattle Genetics, Acetylon Pharmaceuticals, AbbVie Pharma, Astellas Pharma, Celegene, Millennium Pharmaceuticals.: Honoraria, Research Funding, Speakers Bureau.


PLoS ONE ◽  
2010 ◽  
Vol 5 (10) ◽  
pp. e13592 ◽  
Author(s):  
Tania Crucitti ◽  
Katrien Fransen ◽  
Rashika Maharaj ◽  
Tom Tenywa ◽  
Marguerite Massinga Loembé ◽  
...  

Blood ◽  
2020 ◽  
Vol 136 (Supplement 1) ◽  
pp. 32-33
Author(s):  
Zahoor Ahmed ◽  
Karun Neupane ◽  
Rabia Ashraf ◽  
Amna Khan ◽  
Moazzam Shahzad ◽  
...  

Introduction: Daratumumab (Dara) is a human anti-CD38 monoclonal antibody approved for multiple myeloma (MM) treatment. Dara has a promising efficacy and a favorable safety profile in newly diagnosed MM (NDMM) patients. This study is focused on the efficacy and safety of Dara when added to the standard care regimen in transplant ineligible NDMM in phase III clinical trials. Methods: We performed a comprehensive database search on four major databases (PubMed, Embase, Cochrane, and Clinicaltrials.gov). Our search strategy included MeSH (Medical Subject Headings) terms and key words for multiple myeloma and Dara including trade names and generic names from date of inception to May 2020. Initial search revealed 587 articles. After excluding review articles, duplicates, and non-relevant articles, two phase III clinical trials were included which reported overall response rate (ORR), and progression free survival (PFS) of transplant ineligible NDMM patients with Dara addition to standard care regimen. Odds ratios (OR) of ORR were computed and hazard ratios (HR) of PFS (along with 95% confidence intervals; CI) were extracted to compute a pooled HR using a fixed effect model in RevMan v.5.4. Results: A total of 1453 transplant ineligible NDMM patients were enrolled and evaluated in two phase III randomized clinical trials. Seven hundred and eighteen patients were in Dara group and 735 patients were in control group. Bahlis et al. (2019) studied Dara + lenolidamide (R) and dexamethasone (d) vs Rd in NDMM pts (n=737) in MAIA phase III trial. Similarly, Mateos et al. (2018) reported the role of Dara + bortezomib (V) + melphalan (M), and prednisone (P) vs VMP in NDMM pts (n=706) in a phase III trial (Alcyone). A pooled analysis of these phase III trials showed ORR (OR: 3.26, 95% CI 2.36-4.49; p < 0.00001, I2 = 0%), and progression free survival (PFS) (HR: 0.53, 95% CI 0.43-0.65; p < 0.00001, I2 = 0%). Achievement of minimal residual disease (MRD) negative status was significant in Dara based regimen as compared to control group (OR: 4.49, 95% CI 3.31-6.37; p < 0.00001, I2 = 0%). Dara addition to standard care regimen (Rd and VMP) decreased the risk of progression/death to 42% (HR: 0.58, 95% CI 0.48-0.70; p < 0.00001, I2 = 0%). The addition of Dara increased the risk of neutropenia (OR: 1.41, 95% CI 1.07-1.85; p < 0.02, I2 = 44%), and pneumonia (OR: 2.25, 95% CI 1.54-3.29; p < 0.0001, I2 = 37%) vs control group. However, decreased risk of anemia (OR: 0.64, 95% CI 0.49-0.85: p < 0.002, I2=30%) was observed in Dara group vs control group (Figure 1). Conclusion: Addition of Dara to the standard care regimen for transplant ineligible NDMM achieved the surrogate end points with improved efficacy and MRD negative status with manageable toxicity. However, data from more randomized controlled trials is needed. Table Disclosures Anwer: Incyte, Seattle Genetics, Acetylon Pharmaceuticals, AbbVie Pharma, Astellas Pharma, Celegene, Millennium Pharmaceuticals.: Honoraria, Research Funding, Speakers Bureau.


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