Researchers highlight ethical implications of clinical trial terminations

The termination of thousands of federal grants that fund clinical trials threatens to reverse substantial progress in understanding and treating the health challenges of marginalized populations, particularly children and adolescents who are already underrepresented in research. 

A new commentary in the medical journal Pediatrics raises important concerns about the ethics of stopping clinical trials before they are completed, especially when those studies involve children and teenagers.

As of July 2025, the National Institutes of Health cut about 4,700 grants connected to more than 200 ongoing clinical trials. These studies planned to involve more than 689,000 people, including roughly 20 percent who were infants, children, and adolescents. Many of these young participants were dealing with serious health challenges such as HIV, substance use, and depression, and the studies specifically focused on improving the health of people who identify as Black, Latinx, or sexual and gender minority.

The current terminations threaten to upend the progress made in the past few decades, write Amelia Knopf, associate professor at the Indiana University School of Nursing, Kathryn Macapagal, associate professor at Northwestern University Feinberg School of Medicine, and Kimberly Nelson, associate professor at Boston University School of Public Health.

In the commentary, titled "Ethical Implications of Study Terminations," the authors examine what happens when these research studies end abruptly. They argue that such sudden closures can break trust and harm participants, especially when the research involves young people. They also note that these actions conflict with long-standing ethical principles outlined in the Belmont Report-federal guidelines published in 1979 that outline three main principles for human research: respect for persons, beneficence, and justice.

"Trust between researchers and research participants is an essential part of any study and can take a long time to develop, particularly with participants who have been historically excluded from research or marginalized in our society," says Nelson, who studies ethical and legal issues involved in sexual health research and interventions with adolescents. "Stopping a clinical trial in the middle of data collection-not for safety or scientific reasons, but for political reasons-is a violation of that trust. It is an inherent breach of the agreement that was made between the researchers and the participants, where participants accept the risks of participating with the hope that there will be personal and societal benefits if the intervention proves to be effective."

Despite being at greater risk for many of the health conditions that clinical trials address, many of the populations participating in the abruptly canceled clinical trials are underrepresented in this research. In particular, young people who are able to participate in clinical trials often face concerns or barriers around their ability to consent and confidentiality of sensitive information that they share in these trials.

Knopf, who studies HIV prevention and bioethics in her research, says everyone should be concerned.

In the short-term, children, adolescents, and their families are experiencing disruptions to or the termination of benefits that research participation provides. In some cases, the disruption to funding has resulted in contamination of the study design and participants have had to be withdrawn and their data will not be usable. The long-term impact may be lower trust in research, less willingness to participate, and slower scientific progress."

Amelia Knopf, associate professor, Indiana University School of Nursing

The authors, all adolescent health researchers, have enrolled thousands of young participants in their clinical trials, and further explain the effects of ending these studies suddenly. First, participants are not informed that their studies might be defunded or shut down for political or funding reasons, which challenges the idea of true informed consent. Secondly, closing studies abruptly also makes it harder to know whether treatments work, reducing the value of contributions from participants who agreed to take part to advance public health.

The authors call for better ways to track the effects of study terminations on participants and stronger guidelines to ensure that research projects end in an ethical way.

Tracking the health consequences of terminated studies is more important than ever, but also more difficult, amid recent budget cuts to the federal health agencies that collect this information, as well as significant changes to the way this type of data about marginalized communities is collected and reported. The authors urge foundations and private funders to prioritize research on the health and well-being of these individuals and communities who are being erased from public record.

Importantly, as threats to scientific research continue to unfold, they also emphasize the need for researchers to develop a plan for ethical study termination that respects and honors participants' valuable contributions towards societal good.