Clinical trials in pediatrics

“Children are not little adults.” Almost all aspects of children's health including clinical trials and drug development are poor cousins of adult health. Over the years, pediatricians worldwide caution against blind extrapolation of adult data to children as it may result in considerable harm [1,2]. Also, it is increasingly recognized that the roots of many chronic diseases in adulthood stem from childhood and tackling health issues in children lead to improved health in adults [3,4]. Furthermore, investment in early childhood has long-term benefits in adults not only in health but also in other aspects of life such as education and crime reduction [4,5]. Arguably, health at birth is the single most important predictor of health in adulthood as the inequality of an infant at birth has intergenerational effects [5]. The Carolina Abecedarian Project showed that early childhood programs that are of high quality result in substantial societal benefits (e.g., reduction of crime, increased earnings, better education) [4,5]. A recent publication from this project found that this benefit also translated into improved adult health outcomes [4]. In a randomized trial, Campbell and colleagues described that disadvantaged children who were randomized to the intervention group (early education, health screenings and nutrition program) had significantly lower rates of metabolic syndrome, obesity and hypertension, when aged in their mid-30s, compared with the control group [4]...

Designs for phase I clinical trials with multiple courses of subjects at different doses

The goal of this article is to provide a new design framework and its corresponding estimation for phase I trials. Existing phase I designs assign each subject to one dose level based on responses from previous subjects. Yet it is possible that subjects with neither toxicity nor efficacy responses can be treated at higher dose levels, and their subsequent responses to higher doses will provide more information. In addition, for some trials, it might be possible to obtain multiple responses (repeated measures) from a subject at different dose levels. In this article, a nonparametric estimation method is developed for such studies. We also explore how the designs of multiple doses per subject can be implemented to improve design efficiency. The gain of efficiency from "single dose per subject" to "multiple doses per subject" is evaluated for several scenarios. Our numerical study shows that using "multiple doses per subject" and the proposed estimation method together increases the efficiency substantially.

Decision-theoretic designs for dose-finding clinical trials with multiple outcomes

A decision-theoretic framework is proposed for designing sequential dose-finding trials with multiple outcomes. The optimal strategy is solvable theoretically via backward induction. However, for dose-finding studies involving k doses, the computational complexity is the same as the bandit problem with k-dependent arms, which is computationally prohibitive. We therefore provide two computationally compromised strategies, which is of practical interest as the computational complexity is greatly reduced: one is closely related to the continual reassessment method (CRM), and the other improves CRM and approximates to the optimal strategy better. In particular, we present the framework for phase I/II trials with multiple outcomes. Applications to a pediatric HIV trial and a cancer chemotherapy trial are given to illustrate the proposed approach. Simulation results for the two trials show that the computationally compromised strategy can perform well and appear to be ethical for allocating patients. The proposed framework can provide better approximation to the optimal strategy if more extensive computing is available.

DNA binders in clinical trials and chemotherapy

Cancer has always been a dreadful disease and continues to attract extensive research investigations. Various targets have been identified to restrain cancer. Among these DNA happens to be the most explored one. A wide variety of small molecules, often referred to as `ligands', has been synthesized to target numerous structural features of DNA. The sole purpose of such molecular design has been to interfere with the transcriptional machinery in order to drive the cancer cell toward apoptosis. The mode of action of the DNA targeting ligands focuses either on the sequence-specificity by groove binding and strand cleavage, or by identifying the morphologically distinct higher order structures like that of the G-quadruplex DNA. However, in spite of the extensive research, only a tiny fraction of the molecules have been able to reach clinical trials and only a handful are used in chemotherapy. This review attempts to record the journey of the DNA binding small molecules from its inception to cancer therapy via various modifications at the molecular level. Nevertheless, factors like limited bioavailability, severe toxicities, unfavorable pharmacokinetics etc. still prove to be the major impediments in the field which warrant considerable scope for further research investigations. (C) 2014 Published by Elsevier Ltd.

Risk communication in clinical trials: a cognitive experiment and a survey.

BACKGROUND: A Royal Statistical Society Working Party recently recommended that "Greater use should be made of numerical, as opposed to verbal, descriptions of risk" in first-in-man clinical trials. This echoed the view of many clinicians and psychologists about risk communication. As the clinical trial industry expands rapidly across the globe, it is important to understand risk communication in Asian countries. METHODS: We conducted a cognitive experiment about participation in a hypothetical clinical trial of a pain relief medication and a survey in cancer and arthritis patients in Singapore. In part 1 of the experiment, the patients received information about the risk of side effects in one of three formats (frequency, percentage and verbal descriptor) and in one of two sequences (from least to most severe and from most to least severe), and were asked about their willingness to participate. In part 2, the patients received information about the risk in all three formats, in the same sequence, and were again asked about their willingness to participate. A survey of preference for risk presentation methods and usage of verbal descriptors immediately followed. RESULTS: Willingness to participate and the likelihood of changing one's decision were not affected by the risk presentation methods. Most patients indicated a preference for the frequency format, but patients with primary school or no formal education were indifferent. While the patients used the verbal descriptors "very common", "common" and "very rare" in ways similar to the European Commission's Guidelines, their usage of the descriptors "uncommon" and "rare" was substantially different from the EU's. CONCLUSION: In this sample of Asian cancer and arthritis patients, risk presentation format had no impact on willingness to participate in a clinical trial. However, there is a clear preference for the frequency format. The lay use of verbal descriptors was substantially different from the EU's.

Dose-response relationship in phase 1 clinical trials: a European Drug Development Network (EDDN) Collaboration Study

Introduction: Because a dose–response relationship is characteristic of conventional chemotherapy, this concept is widely used for the development of novel cytotoxic (CTX) drugs. However, the need to reach the MTD to obtain optimal benefit with molecularly targeted agents (MTA) is controversial. In this study, we evaluated the relationship between dose and efficacy in a large cohort of phase I patients with solid tumors.

Experimental Design: We collected data on 1,182 consecutive patients treated in phase I trials in 14 European institutions in 2005–2007. Inclusion criteria were: (i) patients treated within completed single-agent studies in which a maximum-administered dose was defined and (ii) RECIST/survival data available.

Results: Seventy-two percent of patients were included in trials with MTA (N = 854) and 28% in trials with CTX (N = 328). The objective response (OR) rate was 3% and disease control at 6 months was 11%. OR for CTX was associated with higher doses (median 92% of MTD); this was not the case for MTA, where patients achieving OR received a median of 50% of MTD. For trials with MTA, patients treated at intermediate doses (40%–80%) had better survival compared with those receiving low or high doses (P = 0.038). On the contrary, there was a direct association between higher dose and better OS for CTX agents (P = 0.003).

Conclusion: Although these results support the development of novel CTX based on MTD, we found no direct relationship between higher doses and response with MTA in unselected patients. However, the longest OS was seen in patients treated with MTA at intermediate doses (40%–80% of MTD)

The EU Clinical Trials Regulation: Key Priorities, Purposes and Aims and the Implications for Public Health

The replacement of the European Union (EU) Clinical Trials Directive by the new Clinical Trials Regulation (CTR), which entered into force on 16 June 2014 but will not apply before 28 May 2016, provides an opportunity to review the legal and political context within which this important aspect of research law and policy sits and to reflect on the implications for public health. My aim in this article is to relate the context to the key purposes and aims of EU law and policy on clinical trials in order to explain and clarify its orientation. On that basis, I argue that the CTR and the changes it introduces to the law on clinical trials are part of the EU's continued focus on market optimisation. It is this focus that orients and directs the wider pharmaceutical development pipeline, but that undermines the achievement of key public health objectives.

Superior outcome of women with stage I/II cutaneous melanoma: pooled analysis of four European Organisation for Research and Treatment of Cancer phase III trials.

PURPOSE: Several studies observed a female advantage in the prognosis of cutaneous melanoma, for which behavioral factors or an underlying biologic mechanism might be responsible. Using complete and reliable follow-up data from four phase III trials of the European Organisation for Research and Treatment of Cancer (EORTC) Melanoma Group, we explored the female advantage across multiple end points and in relation to other important prognostic indicators. PATIENTS AND METHODS: Patients diagnosed with localized melanoma were included in EORTC adjuvant treatment trials 18832, 18871, 18952, and 18961 and randomly assigned during the period of 1984 to 2005. Cox proportional hazard models were used to calculate hazard ratios (HRs) and 95% CIs for women compared with men, adjusted for age, Breslow thickness, body site, ulceration, performed lymph node dissection, and treatment. RESULTS: A total of 2,672 patients with stage I/II melanoma were included. Women had a highly consistent and independent advantage in overall survival (adjusted HR, 0.70; 95% CI, 0.59 to 0.83), disease-specific survival (adjusted HR, 0.74; 95% CI, 0.62 to 0.88), time to lymph node metastasis (adjusted HR, 0.70; 95% CI, 0.51 to 0.96), and time to distant metastasis (adjusted HR, 0.69; 95% CI, 0.59 to 0.81). Subgroup analysis showed that the female advantage was consistent across all prognostic subgroups (with the possible exception of head and neck melanomas) and in pre- and postmenopausal age groups. CONCLUSION: Women have a consistent and independent relative advantage in all aspects of the progression of localized melanoma of approximately 30%, most likely caused by an underlying biologic sex difference.

An analysis of protocols and publications suggested that most discontinuations of clinical trials were not based on preplanned interim analyses or stopping rules.

OBJECTIVES: To investigate the frequency of interim analyses, stopping rules, and data safety and monitoring boards (DSMBs) in protocols of randomized controlled trials (RCTs); to examine these features across different reasons for trial discontinuation; and to identify discrepancies in reporting between protocols and publications. STUDY DESIGN AND SETTING: We used data from a cohort of RCT protocols approved between 2000 and 2003 by six research ethics committees in Switzerland, Germany, and Canada. RESULTS: Of 894 RCT protocols, 289 prespecified interim analyses (32.3%), 153 stopping rules (17.1%), and 257 DSMBs (28.7%). Overall, 249 of 894 RCTs (27.9%) were prematurely discontinued; mostly due to reasons such as poor recruitment, administrative reasons, or unexpected harm. Forty-six of 249 RCTs (18.4%) were discontinued due to early benefit or futility; of those, 37 (80.4%) were stopped outside a formal interim analysis or stopping rule. Of 515 published RCTs, there were discrepancies between protocols and publications for interim analyses (21.1%), stopping rules (14.4%), and DSMBs (19.6%). CONCLUSION: Two-thirds of RCT protocols did not consider interim analyses, stopping rules, or DSMBs. Most RCTs discontinued for early benefit or futility were stopped without a prespecified mechanism. When assessing trial manuscripts, journals should require access to the protocol.

A Psychosocial Approach to Understanding Causality Assessment in Early Phase Oncology Clinical Trials: A Phenomenological Study

Research Question: What are the psychosocial factors that affect causality assessment in early phase oncology clinical trials? Methods: Thirty-two qualitative interviews were explicated with the aid of “Naturalistic Decision Making”. Data explication consisted of phenomenological reduction, delineating and clustering meaning units, forming themes, and creating a composite summary. Participants were members of the National Cancer Institute of Canada’s Clinical Trial Group Investigative New Drug committee. Results: The process of assigning causality is extremely subjective and full of uncertainty. Physicians had no formal training, nor a tool to assist them with this process. Physicians were apprehensive about their decisions and felt pressure from their patients, as well as the pharmaceutical companies sponsoring the trial. Conclusions: There are many problem areas when attributing causality, all of which have serious consequences, but clinicians used a variety of methods to cope with these problem areas.

Implications for Australian anaesthetists and proceduralists of a recent court decision regarding informed consent and patient positioning

 This article discusses the medicolegal implications of a recent judgment in relation to a patient who suffered significant morbidity as a result of patient positioning during an operative procedure. The patient developed an unexpected serious complication following surgery, in the context of a preoperative consent that did not cover every potential complication or contingency. The court held that the failure to warn of a particular risk that would have prevented the patient from undergoing a procedure but did not occur will not necessarily result in a finding of negligence in relation to another risk where the harm did occur. This finding is well aligned to current clinical practice and at the same time does not abrogate the practitioner's duty to provide a comprehensive list of possible complications during the consent process for any proceduralist. In the context of a procedure requiring anaesthesia, the importance of communication and understanding between the anaesthetist and proceduralist as to which aspects of the consent process are undertaken by whom, and to ensure the process is done comprehensively, is of great importance and is indirectly highlighted by this recent judgment.

Nocebo effects in the treatment of major depression: results from an individual study participant-level meta-analysis of the placebo arm of duloxetine clinical trials

BACKGROUND: The nocebo effect, when a harmless substance creates harmful effects in a person who takes it, is a clinically salient yet seldom studied phenomenon that may be associated with poorer treatment outcomes, perceived adverse events, and treatment discontinuation. The covert presence of nocebo responders in clinical trials may contribute to outcome variance in both placebo and active treatment arms for important primary and secondary endpoints. Nocebo effects are thought to be driven by expectancy and conditioning. METHOD: This study analyzed pooled clinical trial data in the placebo arms of controlled trials of antidepressant medications to investigate variables associated with the emergence of adverse outcomes in placebo-treated participants (N = 2,457). Specifically, we examined treatment-emergent adverse events (TEAEs) and discontinuation in placebo-treated individuals. Trials were commenced between 1993 and 2010 as studies of duloxetine versus active comparator and/or placebo. RESULTS: TEAEs were reported by 1,569 placebo-treated participants (63.9%), with 115 (4.7%) discontinuing from the studies due to TEAEs and 274 (11.2%) showing worsening of Hamilton Depression Rating Scale total score during placebo treatment. There was specifically no evidence to support the expectancy hypothesis, that reported TEAEs were influenced by adverse effects described in the clinical trials participant information and consent forms, or the conditioning hypothesis, that reported TEAEs would be influenced by adverse effect profiles of previous antidepressant medications used by these study participants. There was some evidence to suggest that people who had previously used complementary medications were more likely to report TEAEs. Variables specific to individual studies were the strongest predictors of TEAEs. DISCUSSION: In this study, TEAEs were very common among placebo-treated clinical trial participants. Unexpectedly, there was no evidence to associate TEAEs with adverse clinical outcomes, nor were the conditioning or expectancy hypotheses supported by these data. CONCLUSIONS: The nocebo effect is a common, covert, and poorly understood driver of clinical outcomes that requires further investigation.

Health professionals ethical and legal liability on patient’s inadequate clarification in order to obtain free and informed consent

It is required that patients are provided information about therapeutic possibilities, showing the risks, benefits, prognosis and costs of each possible and indicated alternative. This is an ethical and legal resolution. However, health professionals possess the clinical/technical/scientific knowledge and determine what information will be (or not) provided. The patient in question decides to undergo a treatment, providing his/her free and informed consent on the basis of the data presented. Unfortunately, some professionals may not provide all the information necessary for making an informed decision or, after obtaining the consent of the patient, may provide him information that causes the patient to give up on the treatment initially accepted. Such information, if relevant, and not a supervening fact, should have been provided initially. However, the information may not be entirely true, and bring the patient, for instance, to decide based on inadequately presented risks. The craniofacial rehabilitation of the temporomandibular joint (TMJ) by means of TMJ prosthesis, is indicated in many situations. Often, patients in need of such prostheses have aesthetic and functional problems and the rehabilitation expectations run high. This work presents a case and discusses ethical and legal issues, including the liability of partial and inadequate information to a patient.

Communication about standard treatment options and clinical trials: can we teach doctors new skills to improve patient outcomes?

BACKGROUND: The International Breast Cancer Study Group conducted a phase III trial in Australian/New Zealand (ANZ) and Swiss/German/Austrian (SGA) centres on training doctors in clear and ethical information delivery about treatment options and strategies to encourage shared decision making. METHODS: Medical, surgical, gynaecological and radiation oncologists, and their patients for whom adjuvant breast cancer therapy was indicated, were eligible. Doctors were randomised to participate in a workshop with standardised teaching material and role playing. Patients were recruited in the experimental and control groups before and after the workshop. RESULTS: In ANZ centres, 21 eligible doctors recruited a total of 304 assessable patients. In SGA centres, 41 doctors recruited 390 patients. The training was well accepted. There was no overall effect on patient decisional conflict (primary endpoint) 2 weeks after the consultation. Overall, patients were satisfied with their treatment decision, their consultation and their doctors' consultation skills. Considerable variation was observed in patient outcomes between SGA and ANZ centres; the effect sizes of the intervention were marginal (<0.2). CONCLUSIONS: Shared decision making remains a challenge. A sustained training effect may require more intensive training tailored to the local setting. Cross-cultural differences need attention in conducting trials on communication interventions.

Management of infusion reactions in clinical trials and beyond: the US and EU perspectives

Monoclonal antibodies have expanded our cancer-fighting armamentarium in both the United States and Europe. While in general, monoclonal antibodies are well tolerated and do not have significant overlapping side effects with traditional cytotoxic agents, severe infusion reactions (IRs)--sometimes severe enough to be life threatening--have been reported. The pathophysiology of severe infusion reactions associated with monoclonal antibodies is poorly understood, but mechanisms are beginning to be elucidated. Geographic differences in the incidence of IRs have become apparent. Understanding the risk, recognizing the signs and symptoms, and being ready to promptly manage severe IRs are key for the clinician to avoid unnecessarily discontinuing these effective anticancer agents and prevent potentially tragic consequences for their patients. To date, clinical trials have incorporated monoclonal antibodies into combinations with standard cytotoxic regimens; it is expected that in time clinical trials will be testing promising new combinations utilizing multiple targeted agents, resulting in improved toxicity profiles and efficacy for cancer patients.