COVID-19 studies outnumbered others 3 to 1 in 2020-21

Did you know that approximately 86% of clinical trials are delayed while researchers struggle to find enough participants? Expediting the work of medical research is one of the founding principles of Power as we help patients find and apply to safe clinical trials every day.

To understand more about improving medical studies, we recently undertook a research study of our own. Using data from the U.S. National Library of Medicine, we reviewed the past decade of clinical trials in the U.S. to identify what exactly took place and where things need to change. Here’s a breakdown of where the most clinical trials happened and which medical conditions were studied. We’ve also included insights about how the pandemic affected clinical trials, as well as an outlook on what researchers will be studying in the near future.

Key Findings

Where You’ll Find Clinical Trials in the U.S.

Clinical trials in the U.S. suffer from a double-edged problem: Many studies fail to meet their enrollment targets, while a majority of patients also do not have access to clinical trials at nearby treatment centers. Geography is a major limiting factor in the accessibility of clinical trials, so potential participants and researchers alike can benefit from a high number of studies per square mile in a given area. Here’s a look at where the most clinical trials have recently occurred and which diseases have been studied.

Breast cancer was the most heavily studied condition in the U.S. over the past decade, generally. It was also the top condition studied in 25 out of the 50 U.S. states. Type 1 diabetes was the next most-studied medical condition, appearing at the top of the charts in 13 states.

Breast cancer studies are currently recruiting patients for novel treatments. As the most prevalent medical condition studied by doctors and scientists, breast cancer clinical trials might be located near you or a loved one who qualifies.

Trial Completion Rates

Medical studies may conclude early for a variety of reasons, such as evidence that the intervention is having a negative impact on the treated condition. Lack of funding or trouble recruiting and retaining patients are other possible scenarios. We found that completion rates for American clinical trials are pretty consistent across states, varying by less than 10 percentage points from the highest completion rate (Idaho, 87%) to the second-lowest (Delaware, 79%). To calculate completion rates, we compared the number of completed trials against the number of suspended, terminated, and withdrawn trials.

Wyoming was an outlier, ranking for the lowest completion rate at 67%. However, this state also had the fewest total studies by a significant margin: Alaska, which ranked second to last in terms of trial numbers, had more than twice as many trials as Wyoming.

Effects of the Pandemic on Clinical Trials

From emergency rooms to laboratories, the global COVID-19 outbreak has greatly affected the medical community. The pandemic interrupted or ended hundreds of clinical trials in the U.S., but it also triggered a myriad of new studies as doctors and scientists sought to understand the novel virus. A total of 8,990 clinical trials began in 2020, a decrease of only -5.5% compared to the year before as an explosion of trials related to COVID-19 compensated for a steep decline in studies for most other conditions.

The number of COVID-19 studies from 2020 to 2021 vastly outnumbered studies of all other medical conditions. As thousands were becoming sick and dying every day, researchers rushed to understand the virus and how best to treat patients. Many people also worked tirelessly to develop safe and effective vaccines for Americans of all ages. Volunteers are still needed for multiple COVID-19 clinical trials today.

Despite COVID-19 trials dominating the clinical landscape, three key conditions saw an increase in the number of trials from 2020 to 2021: breast cancer, Type 2 diabetes, and obesity.

Studies shared by the Centers for Disease Control and Prevention (CDC) explain that people with certain medical conditions are more likely to suffer from serious illness or death after contracting COVID-19. This comprehensive list includes cancer, diabetes, and obesity. It’s possible that this connection between underlying health issues and COVID-19 may have contributed to the rise in trials studying these three conditions from 2020 to 2021.

The acceleration of studies focused on COVID-19 in just two years has been astounding. Clinical trials related to coronavirus outpaced lung cancer, heart health, and depression studies. The intense focus on the pandemic (as well as COVID-related restrictions and regulations) delayed other studies and also caused the cancellation of hundreds of trials between 2020 and early 2022. According to our research, more than 700 studies ended prematurely due to COVID-19.

Accessibility to all sorts of clinical trials is important, and a pressing medical condition affecting lots of people can make access to trials even more vital. In the case of COVID-19 trials, Rhode Island, Massachusetts, and Maryland topped the list for the highest density of COVID-19 trials. At the bottom of the list were Alaska, Wyoming, and North Dakota, all of which had less than 1 trial per 10,000 square miles.

The Future of Clinical Trials

Clinical trials focus on different types of interventions to determine if they’re beneficial to a person suffering from a specific medical condition. As we reviewed upcoming studies for 2022, noticeable trends for both drug and behavioral interventions were observed.

Our research showed that behavioral trials are on the rise as drug trials are declining. The study rate for other intervention types, including device, dietary supplement, and procedure interventions, appeared fairly level.

Studies may have multiple intervention types, but COVID-19 trials have been heavily drug-centered since they began in earnest in 2020. Nevertheless, based on the data above, studies registered for 2022 seem to indicate that behavioral trials will overtake drug trials for this disease too.

New reports indicate that medical researchers are beginning to shift their focus away from COVID-19. Some researchers also believe the pandemic has brought about positive changes in their field. For example, more efficient protocols were implemented, including accelerating the adoption of remote methods of monitoring trial participants. Virtual trials and remote monitoring can have a real positive impact on participation and lower barriers, especially in places where a physical lack of trial facilities can be a roadblock.

Sex Bias in Medical Studies

The vast majority of clinical trials include both men and women; however, disparities between studies on men’s and women’s health still exist. It’s important to fix this issue, as men and women can respond differently to the same disease, intervention, or medication.

About 88% of clinical trials target both men and women, however, female-only studies are more than twice as common as those exclusively for men (8.6% vs. 3.6%, respectively). In 2021, the increase in the share of women’s health studies—and the accompanying decrease in men’s health studies—was the largest single-year change in the last decade. The share of women-targeted studies increased by about 3.5% from 2020 to 2021, with about 70 more studies targeting women that began in 2021 than in 2020.

While the current bias in terms of total studies leans toward women’s health, it’s important to note that both men and women are underrepresented in the clinical trials of different medical fields. A recent Northwestern Medicine study found that men are underrepresented in clinical trials for the following:

In particular, trials for musculoskeletal disease and trauma underrepresented men: The study concluded that there was an 11.3% difference between representation and proportion of disability-adjusted-life-years (DALYs) for male trial populations.

Researchers also concluded that women need more representation in clinical trials for the following, with a 3% difference in representation for each:

Clinical trials drive clinical practice, so studies lacking diversity can negatively impact or neglect one gender or sex over another. The same Northwestern Medicine study found that one of the top reasons for FDA drug recall is adverse effects in women due to a lack of representation in trial populations.

Power Makes It Easy for Patients to Find Promising New Treatments

Power was created out of personal experience; we know how you feel because we’ve been there, too. Medical research takes a long time, which is something a lot of patients don’t have. Power accelerates medical innovation by connecting people to potentially life-saving clinical trials at top hospitals. Everything is all online and easy to understand, for the first time ever. Search clinical trials to find a promising treatment for yourself or a loved one today.

Methodology and Limitations

Studies were collected from the U.S. National Library of Medicine’s ClinicalTrials.gov website via the Clinical Trials Transformation Initiative’s AACT database. Studies included in this analysis were limited to those with a start date between February 4, 2012, and February 4, 2022, and with at least one operating facility in the United States, excluding the District of Columbia and Puerto Rico.

Note that when considering conditions addressed by studies, overly broad or nonspecific conditions were excluded from rankings and lists. For example, the conditions “neoplasms,” “carcinoma,” and “disease” were excluded, while more specific variants of these conditions were not. For example, “breast neoplasms” and “prostatic neoplasms” were included.

Population and land area estimates for each of the 50 states were sourced from the U.S. Census Bureau.

Fair Use Statement

If you found this analysis of clinical trials in the United States insightful, interesting, or worthy of sharing, feel free to share it with others for noncommercial purposes only. Please link back to this article as a credit to our work.