Types of Clinical Research for COVID-19

A quick search on the internet for “types of clinical trials” yields a variety of descriptions: observational studies, interventional studies, treatment, prevention, phases of clinical trials. But what are all these different types of research, and why are they needed?

Researchers in science and medicine don’t always know how a disease works in the human body. Therefore, finding a medicine to treat or prevent that disease can be difficult. An approach may be tested that seems promising at first but then ends up not working as well as originally anticipated. Researchers learn from those findings, adapt, and try a different approach.

All that learning and adapting is one reason why there are different types of studies. Researchers learn different things simply by asking different questions.

As the world works to quickly learn about COVID-19—how the virus is spread, how it acts in the human body, and how the disease it causes might be treated or prevented—a mix of research studies is underway. This brief guide explains the different types of studies for COVID-19 and what researchers hope to learn from them.

Epidemiology studies

Generally speaking, epidemiology is the study of how, when, and where diseases occur among populations of people. These studies measure the incidence of a particular disease (the number of new cases occurring) and prevalence of disease (the number of new and continuing cases) over time. This information is useful for planning a public health response to the needs in a specific area.

Epidemiology studies aren’t usually classified as “trials.” Instead, they are referred to as “observational studies” because they don’t introduce any type of intervention to affect or change the disease. They simply measure and observe. This includes measuring the disease of interest, as well as various factors that may impact the occurrence, severity, or course of a disease. Understanding what factors impact risk for disease is an important part of understanding how to reduce or prevent the spread of disease.

With COVID-19, researchers have been working to understand all the ways that the disease may be passed from one person to another. When that is understood, then precautions can be taken to reduce the spread of the disease. Reducing the spread of COVID-19 is why current guidelines recommend social distancing, wearing masks, washing hands, and avoiding touching your face.

To learn more general principles of epidemiology studies, check out this video from “Let’s Learn Public Health.”

Treatment trials

Treatment trials are designed to assess whether a potential new medicine can help someone recover from disease. In the case of COVID-19, there are a few types of treatment trials currently underway. As more is learned about the disease, it is possible that other types of treatment trials will be developed.

• Some clinical trials are investigating potential treatments for the symptoms of COVID-19, perhaps preventing mild symptoms from becoming more serious and serious symptoms from becoming deadly. One severe symptom of COVID-19 is called a cytokine storm. This “storm” describes an over-active immune response and can lead to the breakdown of several of the body’s systems. Some clinical trials are investigating whether the study medication can reverse the over-active immune response and allow people to recover.
• COVID-19 is the disease caused by the novel coronavirus called SARS-CoV-2. Antiviral treatments are currently being studied to see if the study medication can prevent the virus from replicating or growing in the human body. If the growth of the virus can be slowed or stopped, that might allow the body’s own immune system to clear the virus, and it might reduce the severity of symptoms of COVID-19. The challenge for these trials is figuring out the most effective way to stop the virus growth cycle while not causing unintended harm to the body’s healthy cells.
• Other clinical trials are trying to determine whether the use of antibodies may boost the body’s ability to fight infection and reduce the severity of symptoms. Antibodies are produced naturally in the human body and help the immune system recognize germs such as viruses and mark them for destruction. Some clinical trials are using antibodies collected from the plasma of a person who had COVID-19 and recovered, and then infused into someone with an active infection. Others are using monoclonal antibodies, which are created in a laboratory. Like the body’s own antibodies, monoclonal antibodies recognize specific targets.

Lilly is conducting clinical trials in a couple of these research areas.

Vaccine trials

Vaccine trials are a type of interventional research. People volunteer to have a weakened form of a virus injected into their bodies, which triggers their immune system to recognize and respond to the disease if they contract it later. This approach stimulates the immune system but is unlikely to make someone sick. In the same way that exercising on a regular basis helps build up muscle strength and endurance, a vaccine helps the immune system to be more prepared to combat a new virus.

Several studies for potential vaccines for COVID-19 are underway, though none are being conducted by Lilly. ClinicalTrials.gov provides a list of vaccine studies being conducted by other companies and institutions.

Diversity and Speed

Across all these types of studies, it is important to include a representative population so that the findings can be broadly applied. That means people of all ages, genders and gender identities, ethnicities, races, and socio-economic status groups must be given an opportunity to participate. So far, researchers have learned that the disease affects some groups more severely than others. It may be that the potential treatments work differently in some population groups, as well, but only the research can determine that, and only if those people participate in the trials.

The scientific and medical research is moving faster than ever before, with programs like the U.S. FDA’s Coronavirus Treatment Acceleration Program (CTAP). What’s more, scientific and medical journals are working to publish findings from research studies more quickly, so that dependable information can be shared with experts and laypeople.

If you or a loved one want to contribute to the scientific and medical body of knowledge about COVID-19, consider participating in a clinical trial. Review options on the listings below to see if one may be a good fit.

If you want to read more about specific treatments currently being studied for COVID-19, check out this overview.