Placebo-controlled clinical trials: how trial documents justify the use of randomisation and placebo

Challenges, unmet needs and future directions - a critical evaluation of the clinical trial landscape in schizophrenia research

INTRODUCTION

Developing novel antipsychotic mechanisms of action and repurposing established compounds for the treatment of schizophrenia is of utmost importance to improve relevant symptom domains and to improve the risk/benefit ratio of antipsychotic compounds. Novel trial design concepts, pathophysiology-based targeted treatment approaches, or even the return to old values may improve schizophrenia outcomes in the future.

AREAS COVERED

In this review of the clinical trial landscape in schizophrenia, we present an overview of the challenges and gaps in current clinical trials and elaborate on potential solutions to improve the outcomes of people with schizophrenia.

EXPERT OPINION

The classic parallel group design may limit substantial advantages in drug approval or repurposing. Collaborative approaches between regulatory authorities, industry, academia, and funding agencies are needed to overcome barriers in clinical schizophrenia research to allow for meaningful outcome improvements for the patients.

Acceptability of Self-Management Group Education to Reduce Fear of Hypoglycemia as a Barrier to Physical Activity in Adults With Type 1 Diabetes: A Mixed Methods Approach

OBJECTIVES

Mixed methods were used to evaluate a group self-management education intervention to address type 1 diabetes (T1D)-specific barriers to physical activity (PA). We evaluated the acceptability of study resources and procedures.

METHODS

Consenting participants from a quantitative evaluation (n=70) were invited to participate in 1 of 5 focus groups. Interviews explored the acceptability of procedures across the randomized controlled trial schedule, acceptability of the intervention/control workshops and resources and the perceived effectiveness of the intervention/control on participant outcomes. The use and helpfulness of intervention take-home resources, Facebook data and fidelity coding were also examined to inform other aspects of intervention acceptability.

RESULTS

Twenty-one focus group participants from control or intervention arms participated in 1 of the 5 focus groups. Participants were 46±10 years of age; about half were female and had been living with T1D for 23±16 years. Study procedures were widely accepted; however, randomization and some aspects of the questionnaire were of concern to a small number of participants. Group education was acceptable and preferred, but participants expressed ambivalence toward the private Facebook group. Control participants indicated that basic information on PA guidelines and hypoglycemia risk are not currently being provided in standard care. Fidelity assessment confirmed the intervention was delivered consistently and was facilitated using behaviours and communication skills based on Social Cognitive Theory.

CONCLUSIONS

Future definitive evaluation of this promising intervention should utilize a blinded randomized controlled trial study design. Alterations to the control workshop are required to better reflect standard care in Australia. Our qualitative findings suggest that group education can be an acceptable and preferred method of education in T1D management for PA.

Placebo effects and the molecular biological components involved

Pharmacologically inactive substances have been used in medicine for more than 700 years and can trigger beneficial responses in the human body, which is referred to as the placebo effects or placebo responses. This effect is robust enough to influence psychosocial and physiological responses to the placebo and to active treatments in many settings, which has led to increased interest from researchers. In this article, we summarise the history of placebo, the characteristics of placebo effects and recent advancements reported from the studies on placebo effects and highlight placebome studies to identify various molecular biological components associated with placebo effects. Although placebos have a long history, the placebome concept is still in its infancy. Although behavioural, neurobiological and genetic studies have identified that molecules in the dopamine, opioid, serotonin and endocannabinoid systems might be targets of the placebo effect, placebome studies with a no-treatment control (NTC) are necessary to identify whole-genome genetic targets. Although bioinformatics analysis has identified the molecular placebome module, placebome studies with NTCs are also required to validate the related findings.

The value of bioethical research: A qualitative literature analysis of researchers' statements

Introduction

Value and waste in preclinical and clinical research projects are intensively debated in biomedicine at present. Such different aspects as the need for setting objectives and priorities, improving study design, quality of reporting, and problematic incentives of the academic reward system are addressed. While this debate is also fueled by ethical considerations and thus informed by bioethical research, up to now, the field of bioethics lacks a similar extensive debate. Nonetheless, bioethical research should not go unquestioned regarding its scientific or social value. What exactly constitutes the value of bioethical research, however, remains widely unclear so far.

Methods

This explorative study investigated possible value dimensions for bioethical research by conducting a qualitative literature analysis of researchers’ statements about the value of their studies. 40 bioethics articles published 2015 in four relevant journals (The American Journal of Bioethics, Bioethics, BMC Medical Ethics and Journal of Medical Ethics) were analyzed. The value dimensions of “advancing knowledge” (e.g. research results that are relevant for science itself and for further research) and “application” (e.g. increasing applicability of research results in practice) were used as main deductive categories for the analysis. Further subcategories were inductively generated.

Results

The analysis resulted in 62 subcategories representing a wide range of value dimensions for bioethical research. Of these, 45 were subcategories of “advancing knowledge” and 17 of “application”. In 21 articles, no value dimensions related to “application” was found; the remaining 19 articles mentioned “advancing knowledge” as well as “application”. The value dimensions related to “advancing knowledge” were, in general, more fine-grained.

Conclusions

Even though limitations arise regarding the sample, the study revealed a plethora of value dimensions that can inform further debates about what makes bioethical research valuable for science and society. Besides theoretical reflections on the value of bioethics more meta-research in bioethics is needed.

Informing Adults With Back Pain About Placebo Effects: Randomized Controlled Evaluation of a New Website With Potential to Improve Informed Consent in Clinical Research

Background

Placebo effects and their underpinning mechanisms are increasingly well understood. However, this is poorly communicated to participants in placebo-controlled trials. For valid informed consent, participants should be informed about the potential benefits and risks of participating in placebo-controlled trials. Existing information leaflets often fail to describe the potential benefits and adverse effects associated with placebo allocation. This study tested the effects of a new website designed to inform patients about placebo effects (The Power of Placebos, PoP). PoP was designed using qualitative methods in combination with theory- and evidence-based approaches to ensure it was engaging, informative, and addressed patients’ concerns.

Objective

This study aimed to test the effects of PoP, compared with a control website, on people’s knowledge about placebo and the ability to make an informed choice about taking part in a placebo-controlled trial.

Methods

A total of 350 adults with back pain recruited from 26 general practices in Southern England participated in this Web-based study. Participants were randomly assigned to PoP (which presented scientifically accurate information about placebo effects in an engaging way) or a control website (based on existing information leaflets from UK trials). Participants self-completed Web-based pre- and postintervention questionnaire measures of knowledge about placebo effects and preintervention questionnaire measures of attitudes toward and intentions to participate in a placebo-controlled trial. The 2 primary outcomes were (1) knowledge and (2) informed choice to take part in a placebo-controlled trial (computed from knowledge, attitudes, and intentions).

Results

After viewing PoP, participants had significantly greater knowledge about placebos (mean 8.28 [SD 1.76]; n=158) than participants who viewed the control (mean 5.60 [SD 2.24]; n=174; F_1,329=173.821; P<.001; η²=.346). Participants who viewed PoP were 3.16 times more likely than those who viewed the control to make an informed choice about placebos (χ²₁=36.5; P<.001).

Conclusions

In a sample of adults with back pain, PoP increased knowledge and rates of informed choice about placebos compared with a control website. PoP could be used to improve knowledge about placebo effects in back pain. After essential further development and testing in clinical trial settings, it could support informed consent in placebo-controlled trials.

Empirical evidence against placebo controls

The revised Declaration of Helsinki allows placebo-controlled trials to be used even when there is an established therapy, provided there are adequate 'methodological' reasons for doing so. This seems to violate the principle of beneficence: where there is an established therapy, physicians treating patients with a placebo are withholding a known effective therapy. Because of this problem, we hypothesised that clinical researchers may be unwilling to risk violating the principle of beneficence and employ placebo-controlled trials in cases where there is an established therapy. In this paper, we began to investigate this hypothesis. After summarising the arguments for and against using placebo controls in clinical practice, we exploredthe extent to which placebo-controlled trials are used in cases where there is an established therapy. To do this, we conducted as systematic search for all placebo-controlled trials published in 2015 in the five highest impact general medical journals. We identified 70 placebo-controlled trials. Of these, 66 were for indications where there was no established effective therapy. Only four used a placebo control in spite of there being an available effective therapy. The infrequent use of placebo controlled trials where established therapy exists highlights a seeming discrepancy between what the Declaration of Helsinki allows and what clinical investigators believe to be ethically acceptable. The evidence presented in this paper suggests that the Declaration of Helsinki be reconsidered, and perhaps revised, in light of actual practice.

Informed consent and clinical trials: where is the placebo effect?

Lack of knowledge about placebos affects participants’ understanding of trials and breaches the ethical obligations of researchers, argue C R Blease, F L Bishop, and T J Kaptchuk

How Health Professionals Conceptualize and Represent Placebo Treatment in Clinical Trials and How Their Patients Understand It: Impact on Validity of Informed Consent

Context

Previous studies suggested that many patients, who have given their informed consent to participate in randomized controlled trials (RCT), have somewhat limited understanding of what a placebo treatment is. We hypothesized that the relationship between patients and their health professionals plays a central role in this understanding.

Methods

We interviewed 12 patients included in RCTs (nine suffering from Parkinson’s disease and three from Huntington’s disease) and 18 health professionals involved with RCTs (eight principal investigators, four associated physicians and six clinical research associates). Semi-structured interviews were conducted after the RCTs had ended but before the treatment allocation was revealed.

Results

Only two patients clearly understood the aim of placebo-controlled RCTs. Only one principal investigator said she asks all her patients whether they agree to participate in RCTs. The seven others said they only ask patients who seem more likely to be compliant. Their selection criteria included docility and personality traits associated in other studies with enhanced placebo responses. According to 13 of the 18 health professionals, their relationship with patients may influence the amplitude of the placebo response. All but one clinical research associates added that the placebo response could result from a “maternal” type of care. All principal investigators said they have a strong influence on their patient's decision to participate. Finally, when interviewees were asked to narrate a memory of a medically unexplained healing, in eight of 11 physicians' narratives the beneficiary was a child while in 10 of 12 patients' narratives it was an adult.

Conclusion

Our observations suggest that the interrelationship between health professionals and patients involved in RCTs could be compared to that between parents and children. Therefore, adherence to formal rules regarding informed consent does not ensure a balanced relationship between patients and health professionals.