Healthy volunteers in US phase I clinical trials: Sociodemographic characteristics and participation over time

BACKGROUND

Increasing the diversity of research participants is an important focus of clinical trials. However, little is known regarding who enrolls as healthy volunteers in Phase I clinical trials, which test the safety and tolerability of investigational new drugs. Despite the risk, healthy volunteers can derive no medical benefit from their participation, and they are financially compensated for enrolling.

OBJECTIVE

This study's purpose is to describe sociodemographic characteristics and clinical trial participation histories of healthy people who enroll in US Phase I trials.

METHODS

The HealthyVOICES Project (HVP) is a longitudinal study of healthy individuals who have enrolled in Phase I trials. We describe self-reported sociodemographic information and Phase I trial history from HVP recruitment (May-December 2013) through the project's end three years later (December 2016). Trial experiences are presented as medians and quartiles.

RESULTS

The HVP included 178 participants. Nearly three-fourths of participants were male, and two-thirds were classified as racial and ethnic minorities. We found that some groups of participants were more likely to have completed a greater number of clinical trials over a longer timeframe than others. Those groups included participants who were male, Black, Hispanic, 30-39-years-old, unemployed, had received vocational training in a trade, or had annual household incomes of less than $25,000. Additionally, the greater the number of clinical trials participants had completed, the more likely they were to continue screening for new trials over the course of three years. Participants who pursued clinical trials as a full-time job participated in the greatest number of trials and were the most likely to continuing screening over time.

IMPLICATIONS

Participation as a healthy volunteer in US Phase I trials is driven by social inequalities. Disadvantaged groups tend to participate in a greater number of clinical trials and participate longer than more privileged groups.

Phase I trial compensation: How much do healthy volunteers actually earn from clinical trial enrollment?

Background/aims

Financial compensation for research participation is a major focus of ethical concern regarding human subject recruitment. Phase I trials are sometimes considered to be a lucrative source of income for healthy volunteers, encouraging some people to become “professional guinea pigs.” Yet, little is known about how much these clinical trials actually pay and how much healthy volunteers earn from them.

Methods

As part of a mixed-methods, longitudinal study of healthy volunteers, we required participants to complete clinical trial diaries, or surveys that captured detailed information about screening and enrollment in Phase I trials. Over a 3-year period, participants provided information online or via telephone about each clinical trial for which they screened (e.g. the clinic name, the study’s therapeutic area, the length of the trial, the number of nights spent in the clinic, and the study compensation), and whether they qualified for trial inclusion. Clinical trial diaries generated data about whether participants continued to screen for and enroll in clinical trials and how much money they earned from their participation.

Results

131 participants routinely completed clinical trial diaries or confirmed that they had not screened for any new clinical trials. Together, these participants screened for 1001 clinical trials at 73 research facilities during a 3-year period. Overall, the median clinical trial compensation was US$3070 (range = US$150–US$13,000). Participants seeking new healthy volunteer trials tended to screen for three studies per year, participate in one or two studies, and earn roughly US$4000 annually. Participants who were unemployed earned the most income from clinical trials compared to those with full-time or part-time jobs, and those individuals whom we label “occupational” participants because of their persistent pursuit of clinical trials earned more than people who screened occasionally. Notably, the median annual trial compensation was well below US$10,000 for all employment groups, and most occupational healthy volunteers also earned less than US$10,000 each year. The 10% of participants who earned the most had a median annual income of US$18,885 from clinical trials, and there was significant volatility in these individuals’ earnings from year to year.

Conclusion

Despite the perception that Phase I enrollment can generate significant earnings, it was exceedingly rare for anyone in this study to make more than US$20,000 in a single year, and unusual to earn even between US$10,000 and US$20,000. From an ethics perspective, individual trials might appear to unduly induce enrollment by offering significant sums of money, but given our findings, the larger problem for low-income participants may be the unrealistic perception that clinical trials alone could be a way of earning a living.

Healthy Volunteers' Perceptions of the Benefits of Their Participation in Phase I Clinical Trials

Other than the financial motivations for enrolling in Phase I trials, research on how healthy volunteers perceive the benefits of their trial participation is scant. Using qualitative interviews conducted with 178 U.S. healthy volunteers enrolled in Phase I trials, we investigated how participants described the benefits of their study involvement, including, but not limited to, the financial compensation, and we analyzed how these perceptions varied based on participants' sociodemographic characteristics and clinical trial history. We found that participants detailed economic, societal, and noneconomic personal benefits. We also found differences in participants' perceived benefits based on gender, age, ethnicity, educational attainment, employment status, and number of clinical trials completed. Our study indicates that many healthy volunteers believe they gain more than just the financial compensation when they accept the risks of Phase I participation.

Healthy volunteers' perceptions of risk in US Phase I clinical trials: A mixed-methods study

BACKGROUND

There is limited research on healthy volunteers' perceptions of the risks of Phase I clinical trials. In order to contribute empirically to long-standing ethical concerns about healthy volunteers' involvement in drug development, it is crucial to assess how these participants understand trial risks. The objectives of this study were to investigate (1) participants' views of the overall risks of Phase I trials, (2) their views of the risk of personally being harmed in a trial, and (3) how risk perceptions vary across participants' clinical trial history and sociodemographic characteristics.

METHODS AND FINDINGS

We qualitatively and quantitatively analyzed semi-structured interviews conducted with 178 healthy volunteers who had participated in a diverse range of Phase I trials in the United States. Participants had collective experience in a reported 1,948 Phase I trials (mean = 10.9; median = 5), and they were interviewed as part of a longitudinal study of healthy volunteers' risk perceptions, their trial enrollment decisions, and their routine health behaviors. Participants' qualitative responses were coded, analyzed, and subsequently quantified in order to assess correlations between their risk perceptions and demographics, such as their race/ethnicity, gender, age, educational attainment, employment status, and household income. We found that healthy volunteers often viewed the overall risks of Phase I trials differently than their own personal risk of harm. The majority of our participants thought that Phase I trials were medium, high, or extremely high risk (118 of 178), but most nonetheless felt that they were personally safe from harm (97 of 178). We also found that healthy volunteers in their first year of clinical trial participation, racial and ethnic minority participants, and Hispanic participants tended to view the overall trial risks as high (respectively, Jonckheere-Terpstra, -2.433, p = 0.015; Fisher exact test, p = 0.016; Fisher exact test, p = 0.008), but these groups did not differ in regard to their perceptions of personal risk of harm (respectively, chi-squared, 3.578, p = 0.059; chi-squared, 0.845, p = 0.358; chi-squared, 1.667, p = 0.197). The main limitation of our study comes from quantitatively aggregating data from in-depth interviews, which required the research team to interpret participants' nonstandardized risk narratives.

CONCLUSIONS

Our study demonstrates that healthy volunteers are generally aware of and reflective about Phase I trial risks. The discrepancy in healthy volunteers' views of overall and personal risk sheds light on why healthy volunteers might continue to enroll in clinical trials, even when they view trials on the whole as risky.

Exceptional Risk: Healthy Volunteers' Perceptions of HIV/AIDS Clinical Trials

As with all early-stage testing of investigational drugs, clinical trials targeting HIV/AIDS can pose unknown risks to research subjects. Unlike sick participants seeking a therapeutic benefit, the motivations and barriers for healthy volunteers are more complex and understudied. Drawing on interviews and clinical trial data from 178 healthy volunteers, we examine how they perceive HIV/AIDS studies in the early stages of testing. A subset of healthy volunteers see phase I HIV/AIDS studies as particularly risky for reasons ranging from fear of catching the disease or having long-lasting and uncomfortable side effects to inexplicable fears that they cannot even articulate. Some participants have had past negative experiences in such trials that inform these views, but others cite information from staff and other participants as influential. Healthy volunteers' general fears concerning AIDS also shape their views of participating in phase I HIV/AIDS clinical trials.