Clinical Trials: How and Why They Work

Caesar Djavaherian, MD, MS, FACEP
January 26, 2021

Today we’re taking a deep dive into clinical trials; specifically what they are, who runs and regulates them, and why they were pivotal in helping get the COVID-19 vaccines out to the public safely and effectively.

Clinical trials use medical research involving people to evaluate the effect of an intervention (or medicine) on human health. Clinicians test and evaluate the efficacy of an intervention — in the case of COVID-19, the developed vaccines — to help them determine how it affects the health of the people administered the vaccine.

Here’s a brief deep dive into the clinical trial process.

First, a clinical trial must define protocol. Protocol is a well-defined plan that balances benefits and risks to its patients and answers specific questions. Protocol is put in place so the trial process is precisely repeatable for dependable evaluation.

Clinical trial protocol can include (but isn’t limited to) this key information:

  • A specific trial goal
  • The number of people or patients who will participate
  • Which people qualify for the trial
  • Protection against risks to participants
  • Length of the clinical trial
  • What information will be gathered and how

Clinical trials are unbiased.

Each clinical study is led and conducted by medical professionals, including a principal investigator who’s usually a medical doctor, and a research team composed of healthcare professionals such as doctors, nurses, and social workers. And, naturally, since research is conducted by such professionals, clinical research is conducted in hospitals, doctors' offices, universities, and, sometimes, community clinics.

To ensure that bias isn’t introduced into the trial, researchers use randomization — assignment by chance, not choice — to group participants. For instance, in a trial for medication or vaccine, participants are assigned at random into either the placebo group of the group who receives the trial medication.

Clinical trials can be paid for by corporations or government agencies, but teams of medical professionals control how research is conducted and evaluated.

Clinical trials are sponsored by an entity that does not participate in the research or stand to influence the outcome. Sponsors may include companies (like pharmaceutical companies and academic medical centers), institutions including the government, or individuals. Sponsors can initiate and finance the trial or manage the research, but never actually conduct the research.

There are 3 phases of clinical research required in a trial before a drug can be approved by the FDA for availability to the public.

These three phases of clinical trials must show that the medicine, also known as an intervention, is safe and effective in treating disease before becoming available to the general public. The National Institutes of Health (NIH) explains that as new treatments move through these three phases, more information is gained about the treatment, its risks, and its effectiveness.

At each stage, clinicians evaluate if the intervention is safe. However, In the third stage, the trial protocol must ask and answer, do the benefits outweigh the risks?

If there are possible risks involved, why would people want to participate in a clinical trial?

Clinical research is conducted to find solutions that improve the lives of people like you. When you volunteer to participate, you become a key element in helping clinicians potentially advance medicine and help the public at large. Clinical trials require what is called Informed Consent, meaning researchers must provide potential participants with information that lays out in front of them the potential risks, benefits, and alternatives to the intervention protocol of the study. This information is made absolutely clear through question and answer sessions, verbal instructions, and other activities to ensure patient understanding.

What role did clinical trials play in relation to the COVID-19 vaccine?

Typically it takes a long time to enroll patients into a clinical study but during the COVID-19 pandemic, enrollment was much easier. In order to prove efficacy, you need enough positive results in the control group and since the prevalence of COVID-19 was so high they were able to achieve statistical significance early on.

Developing a drug is expensive and drug companies typically wait for phase 2 studies to be complete before investing in phase 3 trials. Because of the pandemic, the United States and other countries provided funding to vaccine developers to start planning and enrolling patients in phase 3 trials at the same time that phase 2 trials were being performed. This greatly accelerated the drug development timeline without compromising the typical trial standards.

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Caesar Djavaherian, MD, MS, FACEP

As Carbon Health’s Chief Innovation Officer, Caesar Djavaherian, MD, MS, FACEP, guides clinical innovation through product development, service expansion, and partnerships with transformative companies working to improve the healthcare ecosystem. He is an emergency medicine physician, a former high school teacher, and a reformed academic researcher. Caesar co-founded Direct Urgent Care to deliver technology-enabled urgent care throughout the San Francisco Bay Area. He has practiced at New York-Presbyterian Hospital, the University Hospital of Columbia, and Weill Cornell Medicine. In his spare time, Caesar advises healthcare startups, cheers on the Warriors, tries various HIIT workouts, and daydreams about what the future of health will look like.


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