Typhoidal Salmonella human challenge studies: ethical and practical challenges and considerations for low-resource settings.

Typhoidal Salmonella is a major global problem affecting more than 12 million people annually. Controlled human infection models (CHIMs) in high-resource settings have had an important role in accelerating the development of conjugate vaccines against Salmonella Typhi.The typhoidal Salmonella model has an established safety profile in over 2000 volunteers in high-income settings, and trial protocols, with modification, could be readily transferred to new study sites. To date, a typhoidal Salmonella CHIM has not been conducted in a low-resource setting, although it is being considered.Our article describes the challenges posed by a typhoidal Salmonella CHIM in the high-resource setting of Oxford and explores considerations for an endemic setting.Development of CHIMs in endemic settings is scientifically justifiable as it remains unclear whether findings from challenge studies performed in high-resource non-endemic settings can be extrapolated to endemic settings, where the burden of invasive Salmonella is highest. Volunteers are likely to differ across a range of important variables such as previous Salmonella exposure, diet, intestinal microbiota, and genetic profile. CHIMs in endemic settings arguably are ethically justifiable as affected communities are more likely to gain benefit from the study. Local training and research capacity may be bolstered.Safety was of primary importance in the Oxford model. Risk of harm to the individual was mitigated by careful inclusion and exclusion criteria; close monitoring with online diary and daily visits; 24/7 on-call staffing; and access to appropriate hospital facilities with capacity for in-patient admission. Risk of harm to the community was mitigated by exclusion of participants with contact with vulnerable persons; stringent hygiene and sanitation precautions; and demonstration of clearance of Salmonella infection from stool following antibiotic treatment.Safety measures should be more stringent in settings where health systems, transport networks, and sanitation are less robust.We compare the following issues between high- and low-resource settings: scientific justification, risk of harm to the individual and community, benefits to the individual and community, participant understanding, compensation, and regulatory requirements.We conclude that, with careful consideration of country-specific ethical and practical issues, a typhoidal Salmonella CHIM in an endemic setting is possible.

Ethics of alternative trial designs and methods in low-resource settings.

This editorial introduces articles in this Special Issue, which are based on presentations given at the 2017 meeting of the Global Forum of Bioethics in Research meeting. The main themes presented at the meeting were the use of cluster randomized trials, stepped-wedge cluster randomized trials, and controlled human infection models in research conducted in low-resource settings. The editorial sets out which ethical issues may arise in the context of alternative trial designs and describes the articles in this issue that addresses some or more of the ethical issues, such as justification of the research design, risk-benefit evaluations and consent.

Producción de órganos bioartificiales / Artificial organs production

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The limits of disclosure: what research subjects want to know about investigator financial interests.

Research participants' views about investigator financial interests were explored. Reactions ranged from concern to acceptance, indifference, and even encouragement. Although most wanted such information, some said it did not matter, was private, or was burdensome, and other factors were more important to research decisions. Very few said it would affect their research decisions, and many assumed that institutions managed potential conflicts of interest. Although disclosure of investigator financial interest information to research participants is often recommended, its usefulness is limited, especially when participation is desired because of illness.

"He knows that machine is his mortality": old and new social and cultural patterns in the clinical trial of the AbioCor artificial heart.

The clinical trial of the AbioCor artificial heart, initiated in July 2001 and still in process, has taken place within a matrix of social and cultural patterns that are both "old" and new. The old patterns--those that have accompanied previous clinical trials of other vital artificial organs and transplantation in the United States--include "experiment perilous," and courage, heroism, and pioneering themes; "right stuff" motifs; "Americana" symbols; allusions to the meaning of the human heart; connections with a for-profit corporation; and the occurrence of moratoriums. New patterns--those more particular and distinctive to the AbioCor trial--involve the restrictions imposed on releasing information about the post-operative clinical status of the implant recipients; the quasi-institutionalization of a patient advocacy system to represent patient-subjects and their families; and the "crises of success" that were encountered when several of the AbioCor recipients survived longer than expected. In certain instances, old and new patterns have been combined--for example, in some of the idiosyncratic features of the AbioCor-associated lawsuit that has resulted in part from the problem of the "therapeutic misconception," the belief that an experimental intervention is actually intended to be a treatment.

Switching therapy in health economics trials: confronting the confusion.

Should patients in a randomized, pragmatic health economics trial be allowed to switch therapy in mid-trial to that provided in the other arm? Specifically, should patients in the treatment arm (T) be allowed to switch to the therapy of the comparator arm (C) if they need a change of therapy--that is, should TC switches be allowed? Also, should patients in the comparator arm be allowed to switch to the therapy of the treatment arm if they need changes of therapy--should CT switches be allowed? This is a nontrivial issue in study design that has been debated in the clinical trials literature and is currently being handled inconsistently in the health economics literature. In this article, the authors argue that TC switches should always be allowed and that CT switches should be allowed or not depending on the economic question. They further argue that the most common economic question is one that would lead to CT switches not being allowed.

A critique of clinical equipoise. Therapeutic misconception in the ethics of clinical trials.

A predominant ethical view holds that physician-investigators should conduct their research with therapeutic intent. And since a physician offering a therapy wouldn't prescribe second-rate treatments, the experimental intervention and the best proven therapy should appear equally effective. "Clinical equipoise" is necessary. But this perspective is flawed. The ethics of research and of therapy are fundamentally different, and clinical equipoise should be abandoned.

Paying research subjects: participants' perspectives.

OBJECTIVE: To explore the opinions of unpaid healthy volunteers on the payment of research subjects. DESIGN: Prospective cohort. SETTING: Southern Alberta, Canada. PARTICIPANTS: Medically eligible persons responding to recruiting advertisements for a randomised vaccine trial were invited to take part in a study of informed consent at the point at which they formally consented or refused trial participation. Of 72 invited, 67 (62 trial consenters, 5 trial refusers) returned questionnaires at baseline and 54 at follow-up. OUTCOME MEASURES: Proportions of persons who agreed or disagreed with three close-ended statements on the payment of research subjects; themes and categories identified by content analysis of responses to an open-ended question. RESULTS: A minority (43.3%) agreed with paying either patient or healthy volunteer participants. Opinions did not change over time. Participants' comments addressed: benefits and drawbacks to research participation; benefits and drawbacks to paying research participants; conditions under which payment of research subjects would be acceptable, and the nature of acceptable recognition. Acceptable conditions were to improve problematic recruitment, to reimburse costs, and to recognise participants, particularly for their time investment. Both non-monetary and monetary recognition of volunteers were thought to be appropriate. CONCLUSIONS: Most unpaid volunteers disagreed with paying research participants. The themes arising from their comments are similar to those that have been raised by ethicists and suggest that recognising the time and effort of participants should receive greater emphasis than presently occurs.